Phase 1 Dose Escalation Study of CD19/CD22 Chimeric Antigen Receptor (CAR) T Cells in Children and Young Adults With Recurrent or Refractory CD19/CD22-expressing B Cell Malignancies
Phase: PHASE1
Conditions: Lymphoma, Non-Hodgkin, Leukemia, Lymphocytic, B Cell, B-Cell Lymphoma, B-Cell Leukemia, Acute Lymphoid Leukemia, B-Non Hodgkin Lymphoma, B-NHL, B-All, Acute Lymphoblastic Leukemia, Acute Lymphocytic Leukemia
Sponsor: National Cancer Institute (NCI)

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Abbreviated Title: CD19/CD22 T-cell in Peds
Version Date: November 19, 2024
Abbreviated Title: CD19/CD22 T-cell in Peds
NIH Protocol #: 18-C-0059
OSP #: 1711-1696
IBC #: RD-17-IX-06
Version Date: November 19, 2024
NCT Number: NCT03448393
Title: Phase 1 Dose Escalation Study of CD19/CD22 Chimeric Antigen Receptor (CAR) T Cells 
in Children and Young Adults with Recurrent or Refractory CD19/CD22-expressing B Cell 
Malignancies
NCI Principal Investigator:
Nirali Shah, MD
Pediatric Oncology Branch (POB)
Center for Cancer Research (CCR)
National Cancer Institute (NCI)
National Institute of Health (NIH)
Bldg. 10, Room 1W-5750
9000 Rockville Pike, MSC 1806
Bethesda, MD 20892-1806
Phone: (240) 760-6199
Email: Nirali.Shah@nih.gov 
   
Drug 
Name:
Autologous peripheral blood 
lymphocytes (PBL) cultured with 
Interleukin-2; Transduced with 
retroviral (lentiviral) vector 
(CD19/CD22.BB.z) expressing 
CD19/CD22 chimeric antigen 
receptor (CAR); following 
fludarabine (or pentostatin) and 
cyclophosphamide
Cyclophosphamide
Fludarabine
Pentostatin
IND 
Number:
17764
Sponsor:
Center for Cancer Research, NCI, NIH
Manufact
urer:
Clinical Center Department of 
Transfusion Medicine (DTM), 
Center for Cellular Engineering 
(CCE)
Generic
Generic
Generic

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Abbreviated Title: CD19/CD22 T-cell in Peds
Version Date: November 19, 2024
Supplier:
Clinical Center Department of 
Transfusion Medicine (DTM), 
Center for Cellular Engineering 
(CCE)
CC Pharmacy
CC Pharmacy
CC Pharmacy

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Abbreviated Title: CD19/CD22 T-cell in Peds
Version Date: November 19, 2024
PRÉCIS
Background:
•
Acute lymphoblastic leukemia (ALL) accounts for approximately 25% of childhood 
cancer.  Survival rates have improved, but outcomes for some subgroups, including 
infants and young adults remain poor, and survival for patients who relapse is <50%, 
despite allogeneic stem cell transplant following second remission.
•
CD19 immune escape has been observed by several groups following CD19-CAR 
therapy for B-ALL.  Investigation of this phenomenon reveals a complex biology 
responsible for loss or downregulation of CD19 expression observed in these cases.
•
Sequential therapy using CD22-CARs to treat CD19 dim/lo escape is associated with 
rapid development of resistance due to CD22 downregulation.  This trial will test whether 
simultaneous targeting of CD19 and CD22 using a novel bivalent CD19/22-CAR is safe 
and feasible.
Objectives:
•
Assess the safety of administering escalating doses of autologous CD19/CD22-CAR 
engineered T cells that meet established release specifications in children and young 
adults with CD19+CD22+ B cell ALL, isolated CNS ALL, or lymphoma following a 
cyclophosphamide/fludarabine conditioning regimen. 
Eligibility:
•
Participants between > 3 years and < 39 years of age, with CD19+/CD22+ B cell ALL, 
isolated CNS ALL, or lymphoma who have relapsed or have refractory disease after at 
least one standard chemotherapy regimen and one salvage regimen, with no alternative 
curative options who meet standard Phase I eligibility criteria.
Design:
•
Phase I, 3 + 3 dose escalation design using the following dose levels: -1: 1 x 105 
transduced T cells/kg (± 20%); 1: 3 x 105 transduced T cells/kg (± 20%); 2: 1 x 106 
transduced T cells/kg; and 3: 3 x 106 transduced T cells/kg (± 20%); 4: 1 x 107 transduced 
T cells/kg (± 20%).
•
Participants will receive a lymphodepleting preparative regimen of fludarabine (25 
mg/m2/d x 3 on Days -4, -3, -2) and cyclophosphamide (900 mg/m2/d x 1 on Day -2) 
followed by infusion of CD19/CD22-CAR T-cells on D0. Participants who are CAR pre-
treated (with exception for those with an interval HSCT) will receive increased 
lymphodepleting preparative regimen of fludarabine (30ˆ mg/m2/d x 4 on Days -5, -4, -3, 
-2) and cyclophosphamide (600 mg/m2/d x 2 on Days -3, -2) followed by infusion of 
CD19/CD22-CAR T-cells on D0. If fludarabine is unavailable, pentostatin may be given 
as an alternative.
•
Patients will be evaluated sequentially for toxicity, antitumor effects, CAR expansion and 
persistence, as well as research correlatives.

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TABLE OF CONTENTS 
TABLE OF CONTENTS ................................................................................................................4
STATEMENT OF COMPLIANCE ................................................................................................8
1
INTRODUCTION ................................................................................................................9
1.1
Study Objectives ...............................................................................................................9
1.2
Background and Rationale..............................................................................................10
1.3
Production of CD19/CD22 CAR Expressing T cells......................................................21
1.4
Safety Considerations for Bispecific CD19/CD22 CAR Therapy..................................22
1.5
Protocol Summary and Rationale ...................................................................................25
1.6
Pediatric Enrollment .......................................................................................................31
1.7
Correlative Studies Background .....................................................................................31
2
ELIGIBILITY ASSESSMENT AND ENROLLMENT ....................................................36
2.1
Eligibility Criteria ...........................................................................................................36
2.2
Recruitment Strategies ....................................................................................................40
2.3
Screening Evaluation ......................................................................................................40
2.4
Participant Registration and Status Update Procedures..................................................42
3
STUDY IMPLEMENTATION ..........................................................................................44
3.1
Study Design...................................................................................................................44
3.2
Apheresis for Cell Acquisition........................................................................................45
3.3
Cell Processing................................................................................................................45
3.4
Impact of Disease Progression or Delay in Initiation of Protocol Specified Therapy after 
Enrollment .....................................................................................................................................46
3.5
Impact of Intercurrent Illness After Enrollment .............................................................47
3.6
Dose Limiting Toxicity (DLT) / Treatment Limiting Toxicty (TLT) ............................47
3.7
Dose Escalation...............................................................................................................49
3.8
Dose Expansion Cohort ..................................................................................................50
3.9
Lymphodepleting Chemotherapy Regimen ....................................................................51
3.10
CD19/CD22-CAR T Cell Infusion – DAY 0..................................................................54
3.11
Option for Additional Dose(s) of CD19/CD22-CAR T Cells.........................................55
3.12
Option for Remission Maintenance ................................................................................57
3.13
Neurologic and Neurocognitive Evaluation....................................................................58
3.14
Study Calendar................................................................................................................58

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3.15
Protocol Accrual Suspension ..........................................................................................58
3.16
Telemedicine...................................................................................................................59
3.17
Local Evaluations............................................................................................................59
3.18
Cost and Compensation ..................................................................................................59
3.19
Criteria for Removal from Protocol Therapy and Off Study Criteria.............................60
4
CONCOMITANT MEDICATIONS/MEASURES............................................................61
4.1
Concurrent Therapy for Extramedullary Leukemia or CNS Lymphoma: ......................61
4.2
Infection Prophylaxis ......................................................................................................62
4.3
Prophylaxis and Treatment of Tumor Lysis Syndrome in Children...............................62
4.4
Blood Product Support....................................................................................................63
4.5
Hydroxyurea....................................................................................................................63
4.6
Cytokine Release Syndrome ...........................................................................................63
4.7
Neurologic Toxicity ........................................................................................................63
5
BIOSPECIMEN COLLECTION........................................................................................64
5.1
Correlative Studies for Research.....................................................................................64
5.2
Monitoring Gene Therapy Trials: Persistence, and RCL, and Toxicity .........................66
5.3
Sample Storage, Tracking and Disposition.....................................................................66
6
DATA COLLECTION AND EVALUATION ..................................................................68
6.1
Data Collection ...............................................................................................................68
6.2
Data Sharing Plans..........................................................................................................69
6.3
Response Criteria ............................................................................................................70
6.4
Toxicity Criteria..............................................................................................................70
7
NIH REPORTING REQUIREMENTS / DATA SAFETY MONITORING PLAN .........70
7.1
Definitions.......................................................................................................................70
7.2
OHSRP Office of Compliance and Training / IRB Reporting........................................70
7.3
NCI Clinical Director Reporting.....................................................................................71
7.4
Institutional Biosafety Committee (IBC) Reporting Criteria..........................................71
7.5
NIH Required Data and Safety Monitoring Plan............................................................72
8
SPONSOR SAFETY REPORTING...................................................................................73
8.1
Definitions.......................................................................................................................73
8.2
Assessment of Safety Events ..........................................................................................74
8.3
Reporting of Serious Adverse Events .............................................................................74

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8.4
Waiver of Expedited Reporting to CCR .........................................................................75
8.5
Safety Reporting Criteria to the Pharmaceutical Collaborators......................................75
8.6
Reporting Pregnancy.......................................................................................................75
8.7
Regulatory Reporting for Studies Conducted Under CCR-Sponsored IND...................76
8.8
Sponsor Protocol Deviation Reporting ...........................................................................76
9
CLINICAL MONITORING PLAN ...................................................................................77
10
STATISTICAL CONSIDERATIONS ...............................................................................78
10.1
Statistical Hypothesis......................................................................................................78
10.2
Sample Size Determination.............................................................................................78
10.3
Populations for Analyses ................................................................................................80
10.4
Statistical Analyses .........................................................................................................80
11
HUMAN SUBJECTS PROTECTIONS.............................................................................84
11.1
Rationale For Subject Selection......................................................................................84
11.2
Participation of Children.................................................................................................84
11.3
Participation of Subjects Unable to Give Consent..........................................................85
11.4
Evaluation of Benefits and Risks/Discomforts ...............................................................85
11.5
Risks/Benefits Analysis ..................................................................................................88
11.6
Consent and Assent Process and Documentation ...........................................................89
12
REGULATORY AND OPERATIONAL CONSIDERATIONS.......................................91
12.1
Study Discontinuation and Closure.................................................................................91
12.2
Quality Assurance and Quality Control..........................................................................91
12.3
Conflict of Interest Policy...............................................................................................92
12.4
Confidentiality and Privacy ............................................................................................92
13
PHARMACEUTICAL INFORMATION ..........................................................................93
13.1
CD19/CD22-CAR T Cells ..............................................................................................93
13.2
Fludarabine......................................................................................................................94
13.3
Cyclophosphamide..........................................................................................................95
13.4
Pentostatin.......................................................................................................................96
13.5
Supportive Therapies ......................................................................................................96
14
REFERENCES .................................................................................................................101
15
APPENDICES ..................................................................................................................110
15.1
Appendix A: Performance Status Criteria ....................................................................110

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15.2
Appendix B: Study Calendars.......................................................................................111
15.3
Appendix C: Grading of Acute GVHD.........................................................................118
15.4
Appendix D: Guidelines for Grading and Management of Suspected Cytokine Release 
Syndrome.....................................................................................................................................119
15.5
Appendix E: Calculation of Weight for Cell Dose Calculation in Morbidly Obese 
Participants ..................................................................................................................................124
15.6
Appendix F: Response Criteria.....................................................................................125
15.7
Appendix G:  Guidelines for Evaluation, Grading and Treatment of CAR-T Related 
Neurotoxicity ...............................................................................................................................128
15.8
Appendix H: Neurologic and Cognitive Testing Tools ................................................132
15.9
Appendix I: Biospecimen Collection Schedule and Forms ..........................................143
15.10
Appendix J: Suggested Infection Prophylaxis Guidelines............................................153

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STATEMENT OF COMPLIANCE
The trial will be carried out in accordance with International Council for Harmonisation Good 
Clinical Practice (ICH GCP) and the following: 
• United States (US) Code of Federal Regulations (CFR) applicable to clinical studies (45 
CFR Part 46, 21 CFR Part 50, 21 CFR Part 56, 21 CFR Part 312, and/or 21 CFR Part 812) 
National Institutes of Health (NIH)-funded investigators and clinical trial site staff who are 
responsible for the conduct, management, or oversight of NIH-funded clinical trials have 
completed Human Subjects Protection and ICH GCP Training.
The protocol, informed consent form(s), recruitment materials, and all participant materials will 
be submitted to the Institutional Review Board (IRB) for review and approval.  Approval of both 
the protocol and the consent form must be obtained before any participant is enrolled.  Any 
amendment to the protocol will require review and approval by the IRB before the changes are 
implemented to the study.  In addition, all changes to the consent form will be IRB-approved; an 
IRB determination will be made regarding whether a new consent needs to be obtained from 
participants who provided consent, using a previously approved consent form.

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1
INTRODUCTION
1.1
STUDY OBJECTIVES
1.1.1
Primary Objective
1.1.1.1
Assess the safety of administering escalating doses of autologous CD19/CD22-CAR 
engineered T cells that meet established release specifications in children and young 
adults 
with 
CD19+CD22+ 
B 
cell 
ALL 
or 
lymphoma 
following 
a 
cyclophosphamide/fludarabine conditioning regimen.
1.1.2
Secondary Objectives
1.1.2.1
Determine the feasibility of producing CD19/CD22-CAR T cells meeting the established 
release criteria.
1.1.2.2
Evaluate the ability of CD19/CD22-CAR T cells to mediate clinical activity in children 
and young adults with CD19+CD22+ B cell ALL, isolated CNS ALL, or lymphoma.
1.1.3
Exploratory Objectives
1.1.3.1
Evaluate whether participants receiving CD19/CD22-CAR T cells relapse with loss or 
diminished expression of CD19 and/or CD22.
1.1.3.2
Measure persistence of CD19/CD22-CAR T cells in the blood, bone marrow and CSF, 
and explore correlations between CD19/CD22-CAR T cell properties and CAR T cell 
efficacy and persistence. 
1.1.3.3
Analyze alterations in early B cell development induced by immune pressure exerted via 
CD19/CD22-CAR T cells. 
1.1.3.4
Assess neurologic and cognitive effects of the anti-CD19/CD22-CAR engineered T cell 
infusion pre- and post-infusion. 
1.1.3.5
Explore the level CD19/CD22 surface expression and CD19/CD22 site density on 
leukemic blasts and correlate with clinical response to CAR-T cells
1.1.3.6
Explore the role of additional hematologic evaluation to enhance our understanding of 
the hematologic diathesis that can be seen in association with CAR or cytokine mediated 
toxicity.
1.1.3.7
Explore whether sequence-based genomic analysis can detect minimal residual disease 
(MRD) in participants who have persistence of CD19/CAR22+ T cells, and who are MRD 
negative by flow cytometry.
1.1.3.8
Retrospectively grade Cytokine Release Syndrome (CRS) as per the newly established 
American Society for Transplantation and Cellular Therapy (ASTCT) Consensus 
Guidelines that were published in 2019. COMPLETED
1.1.3.9
Explore apheresis and CAR T-cell product characteristics that may be associated with 
clinical outcomes (e.g., CAR T-cell persistence, toxicity and/or efficacy).
1.1.3.10 Explore CAR T-cell expansion by T-cell subsets and immunophenotypic evaluation of 
markers of T-cell activation and/or exhaustion.
1.1.3.11 Describe the toxicity profile after administration of anti CD19/CD22-CAR T cells in 

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children and young adults with isolated CNS disease.
1.1.3.12 Describe the toxicity profile, CAR T cell expansion and persistence, overall response rate, 
and overall survival after reinfusion of anti CD19/CD22 CAR T cells in participants who 
do not have active disease, but who have early loss of CAR T cells, or loss of B cell 
aplasia < 6 months post initial infusion.
1.1.3.13 Evaluate the gut microbiome in participants receiving CAR-T therapy and correlate with 
cytokine release, neurotoxicity, infection, antibiotic use and clinical response.
1.1.3.14 Conduct metabolomic analysis to evaluate how metabolite levels influence efficacy of 
CAR-T cells, and toxicity in pediatric participants treated with CAR-T cell therapy.
1.1.3.15 Evaluate the efficacy of siltuximab as a treatment for cytokine release syndrome and/or 
immune effector cell associated neurotoxicity syndrome.
1.1.3.16 Evalaute the impact of non-fludarabine based lymphodepletion on CAR T-cell efficacy, 
toxicity and CAR T-cell expansion 
1.2
BACKGROUND AND RATIONALE
1.2.1
Acute Lymphoblastic leukemia (ALL) in Children and Young Adults
Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy, accounting for 
approximately 25% of childhood cancer. Disease-free-survival rates have improved during the 
last 20 years to approximately 90% for children with B-ALL(1), however, outcomes for some 
subgroups, including infants and young adults remain poor, despite attempts to intensify 
treatment regimens(2-4).  Survival for patients who relapse remains <50%, despite incorporating 
allogeneic stem cell transplant following second remission. Finally, short-term and long-term 
toxicity remain substantial(5-9).  Novel treatment approaches are needed to improve cure rates 
and diminish toxicity associated with current standard therapy for B-ALL(6). Outcomes for 
children and young adults with B cell lymphoma have also improved during the last two decades, 
although outcomes for patients with B cell lymphoma refractory to frontline therapy remain 
suboptimal(10, 11).
1.2.2
Chimeric Antigen Receptor (CAR) Therapy
1.2.2.1
CD19-CAR Therapy in B-ALL
CARs are non-native receptors that link an antigen-binding domain to cell signaling domain(s).  
When expressed in T cells, CARs endow MHC-unrestricted antigen specificity.  Most 
commonly, CARs utilize a single chain variable fragment (scFv) coupled to TCR zeta and CD28 
or 4-1BB endodomains. Beginning in 2010, several groups published clinical results using CAR 
T cells targeting CD19 for B cell malignancies.  
1.2.2.1.1 CD19 CAR Therapy
CD19 is a 95 kD transmembrane protein with expression restricted to the B cell lineage. 
Expression of CD19 is present from the time of immunoglobulin rearrangement through B cell 
development and maturation until it is lost with terminal plasma cell differentiation(12). It is not 
expressed on primitive hematopoietic stem cells. CAR T cells targeting CD19 first demonstrated 

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impressive clinical efficacy in small case series in adults with B cell lymphomas and chronic 
lymphocytic leukemia(13-15).  The first pediatric report followed shortly after and demonstrated 
striking responses in two children with refractory and relapsed B-ALL(16).  The demonstration 
of exquisite sensitivity of acute B cell leukemias inspired multiple centers to advance translation 
of CD19 targeting CARs. Despite utilizing varying strategies, clinical trials from multiple 
institutions have consistently shown dramatic activity of CD19-CAR T cells in patients with 
relapsed and refractory B-ALL, with complete responses rates of ≥70% across trials(17-20).  
Kochenderfer et al.(20) demonstrated CAR efficacy in aggressive lymphomas and reported 4 out 
of 7 complete responses in adults with refractory DLBCL treated with CD19 CAR T cells.
1.2.2.1.2 CD19-CAR T cell dose level
Over 750 patients have now been treated with CD19-CAR T cells for B cell malignancies.  As 
detailed below, numerous clinical and scientific insights, drawn from this emerging experience 
serve as the basis for the current novel approach to CAR therapy.  Responses following CD19-
CAR therapy for B-ALL occur rapidly, with maximal response observed within 28 days 
following infusion of the engineered T cells.  The relationship between CAR T cell dose and 
efficacy is less direct than that of a non-replicating drug, however there does appear to be a 
threshold dose of CAR T cells required for efficacy and toxicity.  In the phase I study of anti-
CD19 CAR therapy by Lee et al, the dose level of 1 x 106 cells/kg was found to be safe and 
effective, but the higher dose of 3 x 106 cells/kg while effective, was found to exceed the 
maximum tolerated dose(19). Similarly, the work by Kochenderfer et al., 1-2 x 106 cells/kg dose 
has been safely and effectively employed, while higher doses have been associated with 
toxicity(20). In contrast, the lower starting cell dose of 3 x 105 cells/kg tested in the ongoing 
phase I study of anti-CD22 CAR T cells at the NCI (PI-Shah) was largely ineffective in the 
majority of patients treated (1 responder amongst 6), while the 1 x 106 cells/kg dose was, as in 
the anti-CD19 CAR experience, both safe and effective, with the higher cell dose of 3 x 106 
cells/kg associated with potentially more severe toxicity.  In most active clinical studies, the 
recommended dose of CD19-CAR T cells is 1 x 106 cells/kg.  The inclusion of endogenous 
costimulation within CAR constructs permits lower dosing than that required to achieve efficacy 
when using adoptive T cell methods lacking co-stimulatory signals.  
1.2.2.1.2.1 CD19-CAR T cell efficacy  
Independent of the infused T cell dose, anti-leukemic effects generally do not occur in the 
absence of expansion of the CD19-CAR T cells in vivo.  Dramatic CD19-CAR T cell expansion 
can be observed, with >1000-fold expansion occurring within 1-2 weeks in patients with high 
tumor burden.  CAR expansion can be quantified using polymerase chain reaction to measure the 
number of cells with integrated virus or by flow cytometry, where is it not uncommon to observe 
that >70% of all circulating T cells transiently express the engineered CD19-CAR receptor.  
Expansion of CAR T cells is antigen driven, but is greatly enhanced following treatment with a 
lymphodepleting preparative regimen. Extensive preclinical work has demonstrated that 
lymphopenia induces elevations in the availability of cytokines that drive T cell expansion, 
notably IL-7 and IL-15, and that increased availability of such factors lead to enhanced 
expansion and improved efficacy(21).  Based upon this paradigm, the vast majority of clinical 
trials using CAR T cell incorporate a pre-infusion preparative regimen, comprising 
cyclophosphamide and fludarabine, agents known to induce profound lymphocyte depletion. 

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1.2.2.2
CD19-CAR T Cell Therapy Associated Toxicities
1.2.2.2.1 Cytokine release syndrome (CRS)
Dramatic and rapid expansion of CD19-CAR T cells is often associated with toxicity, including 
cytokine release syndrome and neurotoxicity.  Cytokine release syndrome (CRS) has been the 
topic of several reports and reviews(17, 22). In brief, CRS comprises a febrile, sepsis-like picture 
that results from hemodynamic and organ effects of supraphysiologic levels of inflammatory 
cytokines produced directly or indirectly by the activated T cells.  Among the most important of 
these cytokines are IL-6 and IFN-gamma(17-19).  CRS can be safely managed with supportive 
care and in some cases, immunosuppression using anti-IL6R mAbs therapy and 
corticosteroids(22).  Notably, CRS is limited in patients with low tumor burden with 
contributions from any existing normal B cell population, and CRS severity correlates with the 
degree of CAR T cell expansion.  
1.2.2.2.2 Neurotoxicity
Neurotoxicity is also observed in a significant minority (20-30% in most series) of patients(17-
19) with toxicity ranging from mild to severe.  The pathobiology of CD19-CAR associated 
neurotoxicity is not fully understood, but the clinical syndrome is also associated with increased 
expansion of CD19-CAR T cells as well as evidence for CD19-CAR T cells in the cerebrospinal 
fluid.  In as much as patients with high tumor burden often have some level of CNS leukemia, it 
is seen more often in patients with CNS leukemia(19), however, patients without documented 
CNS leukemia or lymphoma can also manifest the syndrome.  Hence, any direct association of 
CNS disease burden to neurotoxicity severity is unclear.  The syndrome typically manifests 
clinically as confusion, aphasia and/or dysmetria, and occasionally seizures.  Radiographic 
changes are typically not observed and the syndrome typically resolves in 1-2 weeks and appears 
fully reversible.  The prevailing hypothesis regarding the pathophysiology of this syndrome is 
that it reflects non-specific neurotoxic effects of cytokines and/or activated T cells, rather than a 
direct on-target effect of CD19-CAR T cells.  Indeed, the dose limiting toxicity of IL-6 when 
administered in a Phase I trial was neurotoxicity and transient aphasia(23).  In further support of 
this hypothesis, the Jensen laboratory at Seattle Children’s Hospital has recently developed a 
rhesus model of neurotoxicity that utilizes a CD20-CAR rather than the CD19-CAR platform 
and the model appears to model the human syndrome well (ASH presentation, unpublished).  
This provides further evidence against a direct, on-target effect involving CD19 in brain tissue.
In the summer of 2016, three deaths were reported as a result of severe neurotoxicity and 
cerebral edema in patients treated with CD19-CAR T cells.  Given that more than 750 patients 
have been treated with these therapeutics, and only one previous death was reported and 
attributed to neurotoxicity associated with status epilepticus, these events were unexpected and 
work is underway to understand the basis for this phenomenon.  Subsequently, two additional 
deaths were noted in the same trial utilizing high dose cyclophosphamide (in the absence of 
fludarabine) and CD19-CAR T cells incorporating a CD28 costimulatory domain.  Notably, 
CAR T cells that incorporate a 4-1BB costimulatory domain do not typically undergo as rapid 
expansion as those using a CD28 costimulatory domain, so we postulate that the risk of fatal or 
very severe neurotoxicity may be reduced with a 4-1BB containing CAR.  However, very 
recently (February 2017, personal communication-Seattle) one case of fatal neurotoxicity 

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(cerebral edema) using a CAR incorporating the 4-1BB costimulatory domain was reported. The 
CAR utilized in this study will incorporate a 4-1BB costimulatory domain.
1.2.2.2.3 Co-stimulatory Signaling
Another major insight gleaned from the substantial clinical experience with CD19-CAR T cells 
for B cell malignancies is the differential impact of distinct costimulatory domains on T cell 
function.  It has become evident that CD28 costimulation facilitates more rapid and higher peak 
T cell expansion(18, 19), it also predisposes T cells to early exhaustion, which leads to poor 
long-term T cell persistence as a result of activation induced cell death(24).  In contrast, 4-1BB 
costimulation is associated with a slower expansion rate, lower peak level, a diminished risk of T 
cell exhaustion and more prolonged persistence following adoptive transfer(24).  Although 
remission induction rates do not appear to differ between CD28 and 4-1BB containing CD19-
CARs, sustained remission likely requires T cell persistence and thus l 4-1BB CARs may confer 
improved long-term outcomes.
1.2.2.2.4 B-cell Aplasia
The cumulative CD19-CAR experience affirms that prolonged B cell aplasia is an expected 
consequence of effective, persistent CD19-CAR therapy.  Similar to the management of patients 
with congenital absence of B cells, and patients treated with chronic rituximab, CAR-mediated B 
cell aplasia can be managed effectively with immunoglobulin replacement therapy(25, 26).  Thus 
far, significant increase in infection susceptibility or other toxicity related to chronic B cell 
depletion has not been noted(18). 
1.2.3
CD19 Immune Escape Following CD19 Directed Immunotherapy
CD19 is universally expressed at high levels on B-ALL at diagnosis and levels of expression do 
not change appreciably following cytotoxic therapy.  Indeed, CD19-based flow cytometry 
provides powerful prognostic impact by measuring minimal residual disease (MRD) following 
standard cytotoxic therapy in B-ALL(27-29).  However, with the introduction of CD19-based 
immunotherapies, relapse with diminished or absent surface CD19 has been increasingly 
observed. CD19 immune escape was first reported following blinatumumab therapy(30), and has 
been observed by several groups following CD19-CAR therapy for B-ALL.(16, 19, 31)  In a 
recent report from Children’s Hospital of Philadelphia of 50 patients rendered into remission 
with CD19-CAR therapy, 40% of patients had relapsed with a median follow-up of 10.5 months, 
and loss of the CD19 target accounted for 65% of the total relapses(32). While the true incidence 
of relapse due to CD19 immune escape has not yet been established, our CD19-CAR experience 
to date implicated CD19 escape as the most common cause of post-CAR relapse in B-ALL. 
Investigation into the biology of CD19 immune escape has identified a complex biology guiding 
the loss or downregulation of CD19 expression. The two distinct pathways of tumor remodeling 
that have been recognized are categorized as the “isoform switch” and “lineage switch”.  The 
majority of cases fall into the isoform switch category, wherein the cells retain all other 
characteristics of B-ALL and there is no clear evidence for alteration in fitness.  In the majority 
of “isoform switch” cases, mRNA specific for CD19 is retained, but is enriched for CD19 
isoforms that preferentially remain intracellular, lack a transmembrane domain, and/or lack the 
epitopes targeted by all CD19-CARs currently under study as well as blinatumomab(33).  Such 
B-ALL cells resultantly express reduced total surface levels of wild-type CD19 or express an 

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aberrant CD19 that lack the epitope targeted by CD19-CARs and blinatumumab. An alternative 
pathway for loss or diminution of CD19 expression involves tumor cells undergoing switching 
from the lymphoid to the myeloid lineage with a resultant population with myeloid markers and 
features that clonally relates to the parental B cell leukemia(31).
1.2.4
CD22-CAR Therapy for B-ALL
The emergence of CD19 immune escape has prompted interest in the development of 
immunotherapies targeting alternative B-ALL cell surface molecules.  CD22 is a 130 kD sialic 
acid binding transmembrane glycoprotein, which belongs to the Siglec superfamily.  Signaling 
via CD22 mediates inhibitory signals on B cell receptor signaling via immunoreceptor tyrosine-
based inhibitory motifs, which are essential for maintenance of B cell tolerance(34-36).  CD22 
expression is restricted to cells of the B lineage. It is expressed on the surface of mature B cells, 
but is not expressed on pluripotent hematopoietic stem cells(37, 38).  The vast majority of B-
lineage malignancies express CD22 including B-ALL and B cell NHL(39-45). 
Several therapeutics targeting CD22 have been studied in clinical trials with some success.  An 
unconjugated CD22 mAb (Eptratuzumab), mediated modest clinical activity against B-ALL 
alone or when combined with chemotherapy in single arm studies(46-48).  CD22 is rapidly 
internalized following antigen binding, leading to development of CD22 antibody drug 
conjugates and immunotoxins. Inotuzumab, an CD22 mAb conjugated to calicheamicin, 
mediated complete responses in 81% of patients with relapsed/refractory B-ALL(49). 
Moxetumumab, an anti-CD22 genetically linked to pseudomonas exotoxin mediated clinical 
activity in hairy cell leukemia(50) and B-ALL(51), but benefits were transient due to the agent’s 
short half-life, and substantial immunogenicity, which precluded repetitive cycles. 90Y-
conjugated epratuzumab mediated complete responses in 3 of 17 B-ALL patients treated, but this 
was associated with associated with pancytopenia due to radiotoxicity.(48)
Our group sought to develop a chimeric antigen receptor targeting CD22. A variety of binding 
domains, hinge regions and costimulatory domains were compared for efficacy based upon 
killing of cell lines in vitro and the capacity to eradicate human B-ALL xenografts in 
immunodeficient mice.  The lead candidate incorporates the fully human scFv m971, which 
recognizes a membrane proximal epitope on CD22(41),(52);. Among other therapeutics targeting 
CD22 currently or previously in clinical trials, none have utilized this binding domain. The lead 
candidate also has a very short hinge region, and incorporates the TCR zeta signaling domain 
and the 4-1BB endodomain, which was selected based upon superior functionality compared to 
the CD28 endodomain(24). 
Clinical testing of this first chimeric antigen receptor targeting CD22 is under study at the 
Pediatric Oncology Branch (POB) of the National Cancer Institute (NCI) in children and young 
adults with B-ALL. Results from the first sixteen patients treated are encouraging.  The first dose 
level tested of 3 x 105/kg was chosen to be lower than the current standard CD19-CAR dosing 
because this was a first in human study.  Six patients received this dose with one experiencing an 
MRD negative CR.  A second patient demonstrated signs of clinical activity as evidenced by a 
substantial reduction in circulating blasts, but the patient subsequently developed rapid disease 
progression and did not achieve a CR. At the second dose level, 1 x 106/kg, 8 of 10 patients 
experienced an MRD negative CR.  Each of the remissions induced at the 1 x 106 dose level 
were associated with persistent CD22-CAR T cells in the peripheral blood. One of the patients 

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from this initial cohort remains in an ongoing remission at 18 months post CAR therapy with 
ongoing detection of CAR T cells.  At dose level three, 3 x 106/kg, the first patient developed 
grade 4 hypoxia following CAR T cell infusion. A second patient was safely treated at this dose 
level without a DLT. Based on the single DLT at the third dose level and clinical activity 
appreciated at dose level 2, a decision was made to expand dose level 2 to further explore 
activity and safety.  Eight additional patients have since been treated at dose level 2 (1 x 106/kg) 
to further explore activity and safety.  Nine patients (56%) achieved a complete remission, with 8 
out of 10 responders (80%) receiving dose levels ≥ 1 x 106 CD22 CAR/kg. Of the sixteen 
patients enrolled, nine had CD19 neg/dim B-ALL as a result of previous CD19 directed 
immunotherapy, and six of these patients achieved complete remission to CD22-CAR. Updated 
results of this CD22 CAR trial were recently published upon. 58 patients have been treated to 
date, with 50/58 (86.2%) of patients having had CRS. Of the 57 infused patients evaluable for 
response, 40/57 patients achieved a complete response, of whom 35 were MRD negative(53).
From this small series, we conclude that the CD22-CAR shows many characteristics that are 
similar to the CD19-CAR.  Response occurs rapidly within 28 days and correlates with CD22-
CAR expansion.  Cytokine release syndrome did occur, but the maximal severity was Grade 2.  
The CD22-CAR T cells traffic to the spinal fluid at levels similar to that observed with CD19-
CAR.  Although a cyclophosphamide/fludarabine based preparative regimen was used, we 
observed minimal neurotoxicity (Grade 1) in two patients, all of which was reversible.  Two 
patients experienced grade 5 toxicity at the expansion cohort. This include one patient who 
developed bacterial infection following recovery from CRS and neutrophil recovery and 
ultimately died from multi-organ failure due to infection. An additional patient developed grade 
5 ARDS in the setting of CRS as expected, since the CD22-CAR incorporates a 4-1BB 
costimulatory domain, patients maintained CAR persistence and persistent B cell depletion at 90 
days, with some evidence for persistent CAR cells out to 9 and 18 months seen in those patients 
who are in the longest remission.  This CD22 CAR is the first alternative to CD19 for CAR 
based immunotherapy for B-ALL.  Given that CD22 is expressed on numerous other B cell 
malignancies, the results raise the prospect that this CD22-CAR may also provide a novel 
therapeutic for application across the spectrum of B cell malignancies.
The CD22-CAR also provides the first evidence for a salvage immunotherapy, in the event of 
relapsed disease or resistance to front line immunotherapy.  
1.2.5
CD22 Immune escape following CD22 targeted immunotherapy
In the current CD22-CAR T cell trial being conducted by POB NCI, alterations in CD22 site 
density have been observed in a few of the relapsed patients. One notable example is being seen, 
following CD22 directed antibody therapy (inotuzumab), where several patients have emerged 
with partial loss of CD22 on leukemia blasts after this therapy. Similarly, following anti-CD22 
CAR therapy, one patient, at the 6-month restaging evaluation revealed a decrease in CD22 site 
density from over 10,000 sites/cell prior to CD22-CAR therapy, to approximately 1000 sites/cell 
at relapse in the presence of circulating anti-CD22 CAR T-cells (see Figure 1, Patient #8). 
Another patient, known to be CD19 negative at the time of CD22-CAR infusion, developed 
relapsed leukemia at 5 months post-CD22 CAR therapy that was partially positive for both CD19 
and CD22 (see Figure 1, Patient #9). Another patient who was known to be CD19 negative prior 
to CD22 CAR therapy and had received inotuzumab prior to receiving her CD22 CAR T cells, 
had a bimodal CD22 population noted in her peripheral blood flow with 89% of blasts 

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expressing CD22; bone marrow flow cytometry showed complete CD22+ population at that 
time. Despite this, at 1-month post CD22 CAR therapy, she had a complete MRD negative 
remission, with 41% circulating CD22 CAR T cells in her bone marrow. At her 2-month 
restaging visit, despite a high level of circulating CD22 CAR T cells, she relapsed with CD19-
/CD22- ALL (see Figure 1, Patient #15). Additionally, another patient who was previously 
refractory to blinatumomab and CD19 CAR, attained a complete remission but had a decrease in 
CD22 site density, from approximately 3,500 sites per cell prior to CD22 CAR therapy and post 
infusion, CD22 site density of less than 500 sites/cell at 1 month (see Figure 1, Patient #11). The 
mechanism for CD22 surface expression alteration is unknown at this time, however constant 
CAR immune pressure as seen in CD19-CAR treated patients may contribute to this phenomena. 
Figure 1: CD22 Site Density with CD22-CAR T Cell Therapy
In summary, the reported clinical trial experience using CAR-T cells for management of B cell 
malignancies and the toxicity profile, supports use of this treatment strategy for children and 
young adults with no alternative curative options.  We believe the lower CRS and neurologic 
toxicity rates observed using 4-1BB costimulation along with evidence that 4-1BB provides 
persistent CAR-T expression with durable responses supports the use of 4-1BB costimulation in 
our CAR19/CD22 construct.
1.2.6
Development of a Bi-specific CD19/CD22-CAR for B-cell Malignancies
Sequential treatment with CD19-CAR followed by CD22-CAR reserved for patients who 
develop CD19 neg/dim resistance provides one approach to immune targeting of B-ALL.  
However, there is concern that a similar loss of CD22 expression might also occur as a result of 
an immune response directed solely toward one target.  Furthermore, we noted that one patient 
treated with CD22-CAR developed recurrence at 3 months with increased expression of CD19 at 
that timepoint.  Therefore, we posit that the long-term effectiveness of CARs could be enhanced 
if the CAR could simultaneously target two antigens, such as CD19 and CD22.  
To this end, we developed a chimeric antigen receptor with transmembrane and signaling 
domains that are essentially identical to the CD22-CAR, but in place of an scFv targeting 
singular CD-22, we incorporate scFvs identical to those incorporated into the original CD19-
CAR (fmc63) and the CD22-CAR described above (m971), Figure 2.
Figure 2: Loop CAR Construction Using CD19 & CD22 scFv From Single CAR Construct

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The anti-leukemia activity of bispecific loop CAR T cells was established and compared to 
CARs targeting the CD19 and CD22 antigens. Lentiviral vectors containing supernatants were 
generated for the CD19, CD22, and bispecific CAR constructs and T cells were transduced to 
express respective CARs. Negative controls using mock (non-transduced) T cells were cultured 
and activated in parallel. We then tested in vivo CAR cytotoxicity.  NSG immunodeficient mice 
were injected with the NALM6 leukemia cell line that has been permanently transfected to 
express the luciferase gene (termed NALM6-GL, gift of S. Grupp and D. Barret, Children’s 
Hospital of Pennsylvania).  NALM6-GL leukemia growth within a xenograft model can be 
detected by imaging the mice with a sensitive CCD camera that can measure photons produced 
by the luciferase enzyme following injection of the mice with the luciferin substrate. On day 3, 
upon establishment of detectable leukemia, mice were injected with CAR T cells transduced with 
either CD19, CD22, bispecific loop CAR, or control. The bispecific loop CAR had comparable 
activity in xenografts compared to CD19-CARs and CD22-CARs (Figure 3).  This bivalent, 
bispecific CAR has the advantage of being able to recognize CD19+CD22+ cells, as well as 
CD19+CD22– and CD19–CD22+ cells.
CML cell line K562 was artificially transduced with CD19 or CD22 or both to express the target 
antigens. K562 cells served as the negative control. 1E5 CAR T cells were washed 3 times and 
then co-incubated with 1E5 target cells in RPMI media at 370C. After 14 hours, culture 
supernatant was harvested and the production of the cytokines was measured with ELISA kits. 
IL-2 production by the Loop CAR was comparable to that seen with the CD19 CAR (Figure 4).

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Figure 3: Potent in vivo Activity of Bispecific CAR T cells against CD19+CD22+Leukemia
NSG (immunodeficient) mice were injected with 1 x 106 NALM6-GL cells on day 0 and 
images taken on day 3 demonstrate, with luciferin substrate, the presence of leukemia in all 
animals. On day 3, each mouse group was injected with 3 x 106 CAR T cells transduced with 
either CD19, CD22, Bispecific, or control. Mice were re-imaged weekly and equivalent anti-
leukemic activity was seen in Bispecific Loop CAR.

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Figure 4: Cytokine production by ELISA in vitro
Interferon-gamma production was also seen with use of the bispecific CAR against both CD19 
negative and CD22 negative samples (Figure 5).
Figure 5: IFN-gamma production with CARS
Additional testing was performed pre-clinically to determine if the bispecific loop CAR had 
activity against CD19 dim populations. After treatment with blinatumomab, a patient relapsed 
with a CD19low and CD19high leukemia. A patient derived xenograft model (PDX) was created 
with this leukemia phenotype. At day 0, 1 x 106 leukemia cells where injected into two NSG 
mouse groups, experiment vs control. At day 9, when leukemia was detected by flow cytometry, 
bispecific loop CAR T cells and non-transduced mock T cells were injected into the 
experimental and control groups respectively. The bispecific loop CAR demonstrated excellent 
activity and cured this post CD19 directed immunotherapy relapse. 

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Patient samples post CD19-directed immunotherapy shows CD19low and CD19high population in 
addition to CD22 population. NSG mice were injected with 1 x 106 leukemia cells and treated on 
day 9 with 3 x 106 CAR T cells of bispecific loop CAR or non-transduced T cells. The bispecific 
loop CAR was able to eradicate PDX sample and mice remained disease free up to 49 days 
(Figure 6).
Figure 6: Relapsed Patient Sample Cured in Xenograft Model After Treatment with 
Bispecific Loop CAR T cells.
Other strategies that could provide a dual-targeting strategy include either 1. Co-transduction of 
both CARs into one T cell or 2. Co-infusion strategy by which both anti-CD19 CAR and anti-
CD22 CAR T cells would be simultaneously infused. Both were considered as alternative 
approaches to the currently proposed bi-specific CAR strategy. In regards to the first strategy of 
co-transduction, although a reasonable concept, preclinical studies performed in the Fry lab 
(POB, NCI) demonstrate that this approach leads to a much lower transduction efficiency than 
desired and is not a clinically feasible approach at this time. (Figure 7, Personal communication- 
Fry lab).
Figure 7: Transduction Efficiencies of CAR Strategy Options
The vectors for CD19, CD22, and the bispecific Loop1 CAR were produced by transient transfection of 
the 293T lenti packaging cell line. Human PBMCs from a healthy donor were activated with CD3/CD28 
microbeads for 24 hours. Activated T cells were then transduced with the vector individually or co-
transduced with both CD19 and CD22 vectors together. Surface expression of the CD19 CAR and CD22 
CD19_ Lo
CD19_Hi
CD22
353.03
8,606.40
1,536.61
CD19 and CD22 Expression
Density on HMB13
CD19
CD22
CD22
Loop
None
CD19
Loop CAR treatedmice are disease free up to day 49

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CAR were analyzed on day 8. Co-transduced T cells have much lower expression of both CD19 and 
CD22 CARs compared to the bispecific CAR. The expression of CD19 and CD22 CARs on co-
transduced T cells are not at an equal molar ratio. In contrast, Loop1 CAR has an almost 1:1 ratio in 
expression of CD19 and CD22 CAR, which displays as a diagonal plot.
In regards to a co-infusion model (with either simultaneous or sequential infusion of anti-CD19 
and anti-CD22 directed CAR cells), several concerns emerge.  First, a sequential infusion 
approach, which may be preferred to avoid cumulative infusion related toxicity, is ineffective in 
vivo, as demonstrated below (Figure 8).
Figure 8: Effectiveness of CAR Therapy Administration Options
NSG mice were challenged with 1E6 of NALM6 leukemia on day 0. On 3 day, mice in group 4 to 7 
received 3E6 of CAR+ T cells. Mice in group 1 and group 2 received sequential treatment with 1E6 CD19 
or CD22 CAR+ T cells on day 3 and 3E6 CAR+ T cells of the other CAR on day 7. Mice in group 3 
received co-administration of a total of 6E6 CAR T cells with 3E6 of CD19 CAR and 3E6 of CD22 
CARs on day 3. Mice in group 4 received almost 10E6 of total T cells due to the low expression on the 
co-transduced T cells. Bioluminescent intensity represents tumor burden.
Simultaneous administration, while effective, in this model, may have implications in the clinical 
setting with cumulative toxicity of two different CAR cell expansions—but certainly could be 
explored further. The co-transduction model, shown above, while effective is notably being given 
at much higher doses to achieve this efficacy and is not yet a clinically feasible strategy.
Thus, in proceeding forward with a dual-targeted approach, to explore the safety of a single CAR 
with dual targeting capabilities avoids concern for cumulative toxicity and demonstrates in vivo 
clinical activity. 
1.3
PRODUCTION OF CD19/CD22 CAR EXPRESSING T CELLS
This protocol will test the safety and activity of the bi-specific CD19/CD22-CAR in patients with 
relapsed, refractory B cell malignancies.  Major elements of the treatment regimen, including the 
processing of the cells, the lymphodepleting preparative regimen and dose escalation scheme 
will closely mimic that clinical development of CD19-CAR and CD22-CARs.  Briefly, fresh or 

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cryopreserved peripheral blood mononuclear cells collected via apheresis will be enriched for T 
cells using a CD4/CD8 immunomagnetic bead enrichment.  They will then be activated by co-
culture with immunomagnetic particles expressing anti-CD3 and anti-CD28 mAb. One day 
following activation, replication incompetent lentiviral vector particles containing the 
CD19/CD22.BB.z construct will be added to the culture for transduction.  Cells will be incubated 
for minimum of 9 days with IL-2 (200IU/mL) then harvested and administered fresh or frozen 
for subsequent infusion. PI has the option to extend the culture to day 12.  Cells will be required 
to meet standard release criteria including transduction efficiency based off of protein-L flow 
≥15%, viable T cell content ≥80%, flow identity testing using anti-CD19 idiotype and CD22-
Fc/Siglec2 ≥ 10%, in process sterility, mycoplasma, endotoxin, as well as no evidence for 
replication competent lentivirus.  CAR T cell products are manufactured on the CliniMACS 
Prodigy (Miltenyi Biotec), an automated cell processing device designed for closed-system, 
GMP-compliant manufacturing of cell therapy products.  Manufacturing unit operations on the 
Prodigy are carried out in validated closed-system, presterilized, single-use disposable sets to 
prevent contamination and cross-contamination.  All procedures will take place using good 
manufacturing process guidelines
1.4
SAFETY CONSIDERATIONS FOR BISPECIFIC CD19/CD22 CAR THERAPY
1.4.1
Risk of chemotherapy 
Toxicities resulting from fludarabine and cyclophosphamide in the doses proposed in the current 
study are well known and are what have been used in the prior anti-CD19 CAR and anti-CD22 
CAR protocols conducted at the Pediatric Oncology Branch (POB) of the NCI. Such a 
preparative regimen is designed to decrease the number of endogenous T cells, including T 
regulatory cells that may otherwise suppress CAR T cell cytotoxicity, and to induce increased 
availability of homeostatic cytokines thereby allowing for better engraftment of the transferred 
CAR T cells. The dose limiting toxicity (DLT) for both fludarabine and cyclophosphamide is 
myelosuppression, however myelosuppressive effects are expected to be transient using the 
doses proposed. Other toxicities including fever, nausea, vomiting, stomatitis, diarrhea, anorexia, 
edema, skin rashes, myalgias, headache, agitation, and fatigue should be easily managed with 
appropriate supportive care. Sterile hemorrhagic cystitis occurs in about 20% of patients who 
receive cyclophosphamide but is unlikely given the relatively low dose administered in this trial 
and given that mesna will be used prophylactically as a uroprotective agent. Tumor lysis 
syndrome (TLS) following fludarabine and cyclophosphamide administration can occur in 
patients with advanced bulky disease.  To prevent this, patients will be prescribed allopurinol and 
appropriately hydrated with close monitoring for the development of TLS. Finally, opportunistic 
infections (protozoan, viral, fungal, and bacterial) have been observed post-fludarabine and 
cyclophosphamide, especially in heavily pre-treated individuals. Patients will receive appropriate 
antimicrobial prophylaxis (e.g., Bactrim for PCP prophylaxis) during treatment and for a 
minimum of 6 months following treatment.
1.4.2
Risk of Autoimmunity 
Autoimmune toxicity is a risk of adoptive cell therapy trials for cancer and can occur if the 
transferred populations recognize the target antigen on normal tissues.  Thus far, on-target, off-
tumor toxicity of both CD19-CAR and CD22-CAR T cells has been restricted to B cell aplasia, 
which can be managed with immunoglobulin replacement therapy.  Given that the CD19/CD22-

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CAR tested in this study incorporates scFvs that have already been tested in clinical trials, it is 
unlikely that unexpected autoimmune toxicity will occur, but patients will be monitored closely 
for the occurrence of unexpected toxicity and if it is observed, appropriate supportive care and 
modification to the clinical trial will be instituted.
1.4.3
Risks of Gene Therapy 
Risks of gene therapy include insertional mutagenesis or emergence of replication-competent 
lentivirus (RCL). While insertional mutagenesis is theoretically possible using retroviral vectors, 
this has only been observed in the setting of infants treated for X-SCID using retroviral vector-
mediated gene transfer into CD34+ bone marrow stem cells. In the case of retroviral or lentiviral 
vector-mediated gene transfer into mature T-cells, there has been no evidence of long-term 
toxicities associated with these procedures since the first NCI sponsored gene transfer study in 
1989. Despite the fact that clinical data currently available suggest that the introduction of 
retroviral vectors transduced into mature T-cells is a safe procedure, continued follow-up of all 
gene therapy patients will be performed as required. The proposed protocol follows all current 
FDA guidelines regarding testing and follow up of patients receiving gene transduced cells. 
Similarly, the viral vectors used have been engineered to minimize the risk of emergence of 
replication competent lentivirus, but patients will be monitored according to Recombinant DNA 
Advisory Committee guidelines for several years following receipt of this therapy and in the case 
of the development of second malignancy, all efforts will be made to determine whether 
replication competent retrovirus has emerged. 
Of note, 10 participants on this study had RCL testing performed in real time pre- and post- 
infusion and there was no RCL detection in any of the samples tested. Based on this data, a 
proposal was submitted by the protocol team and approved by the FDA to eliminate culture 
based testing on the infused product, and to eliminate real time testing of patient samples, with a 
plan to archive samples that will be available to be tested at a later date if there is a clinical 
concern. An additional 14 patient samples have been collected and will be stored and tested if 
clinically indicated at a future date. (Note: Testing removed with protocol revisions in September 
2022.)
1.4.4
Risk of Cytokine Release Syndrome 
Cytokine release syndrome occurs in the setting of a variety of immunotherapies including 
following antibody infusions and also following adoptive cell therapy. The clinical picture, now 
described by many groups, is essentially indistinguishable from infection/sepsis, with fever being 
the hallmark sign. The pathophysiology is related to excess cytokine levels, released either 
directly from the adoptively transferred cells or indirectly induced by the immune activation.  
Severe cytokine release syndrome can be associated with signs and symptoms of macrophage 
activation syndrome and hemophagocytic histiocytosis.  Grading and management of CRS in this 
protocol will follow the guidelines set forth by consensus criteria established in 2019 by the 
ASTCT, formerly known as American Society for Blood and Marrow Transplantation (ASBMT) 
(54) which includes diligent supportive care and search for infection, with immunosuppression 
using anti-IL6R mAbs, IL6 mAbs,  and/or corticosteroids reserved for more severe cases.  Using 
such a risk-adapted system for management of CRS has diminished morbidity and mortality 
associated with this syndrome. (See Appendix D)

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1.4.5
Risk of Neurotoxicity
As discussed above, a sizable minority of patients treated with CD19-CAR therapy develop 
reversible neurotoxicity that may range from mild cognitive confusion, to visual hallucinations, 
to lack of responsiveness to commands.  Although the pathophysiology of neurotoxicity is not 
well understood, current concepts hold that it is a non-specific effect of immune activation rather 
than a direct, on-target effect of CD19-CAR T cells.  While immunosuppression appears to 
effectively reverse cytokine release syndrome, treatment with anti-IL6R for neurotoxicity does 
not appear to be effective and may even lead to transient worsening due to elevations in 
circulating IL-6 induced by the mAb. Corticosteroids may have some beneficial effects, but 
controlled trials have not been undertaken and therefore the true effectiveness of corticosteroids 
for management of severe neurotoxicity remains unclear.
Furthermore, we postulate that the risk of fatal or very severe neurotoxicity may be reduced with 
a 4-1BB based on the experience thus far that suggests that 4-1BB costimulatory domain-based 
CARS do not typically undergo as rapid expansion as those using a CD28 costimulatory domain. 
Indeed, lethal neurotoxicity has rarely been reported using a CAR incorporating a 4-1BB 
costimulatory domain. The CAR utilized in this study will incorporate a 4-1BB costimulatory 
domain.
Patients will be monitored carefully for neurotoxicity throughout this study (See section 3.12 for 
additional details). Additionally, we will also have prospective neurologic evaluations performed 
on this protocol to provide additional input and insight into the treatment and management of the 
patients who do develop neurotoxicity.  All patients will be treated prophylactically with 
levetiracetam (Keppra), unless contraindicated, and patients with significant neurotoxicity will 
be monitored closely and treated aggressively as outlined in section 4.7. Prospective 
neurocognitive testing will only be performed in patients with isolated CNS disease (see section 
1.5.5; updated with protocol revisions in September 2022).
1.4.6
Risk of Disseminated Intravascular Coagulation (DIC) and Hemophagocytic 
lymphohistiocytosis (HLA)/ macrophage activation syndrome (MAS)
DIC and HLH/MAS are known complications of CAR therapy,(55, 56) the underlying etiology 
of which is unclear, but believed to be due to an inflammatory response related to CAR Therapy. 
DIC can present as asymptomatic lab findings but can be more severe and present with signs of 
clinical bleeding. Understanding the pathophysiology of DIC is being further explored as an 
exploratory analysis (see section 1.1.3) and the early clinical experience with DIC on this 
protocol suggests that it is a self-resolving process that can be ameliorated with use of steroids. 
Similarly, HLH/MAS—which can manifest as a constellation of symptoms including fever, 
elevated ferritin, hypertriglyceridemia, pancytopenia and hepatic function abnormalities may 
also self-resolve or can be treated with immunosuppressive agents (steroids, chemotherapy, 
Anakinra are a few examples)(57). HLH/MAS may also present with features of coagulopathy, 
so it is currently unclear if the DIC is a manifestation of HLH/MAS, but certainly all of these 
appear to be linked to the CAR-T cell induced inflammatory milieu. Patients treated on this 
protocol will be closely monitored for these findings as they are clinically relevant and may 
require intervention to reduce risks. 

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1.4.7
Use of Adaptive sequencing for MRD monitoring
The persistence of minimal residual disease is a poor prognostic factor in pediatric patients with 
acute lymphoblastic leukemia. Recent use of high-throughput sequencing (HTS) has shown that 
MRD testing using this technique is more sensitive at detecting low levels of leukemia in patient 
samples, as compared to the gold standards of multi-channel flow cytometry (MFC) or allele-
specific oligonucleotide (ASO) PCR amplification(58). Flow cytometry typically permits 
detection of recurrent or persistent disease with sensitivity on the order of 1 cell in 104, while 
PCR can detect disease on the order of 1 cell in 105. Various groups have tested new methods of 
MRD monitoring using next generation sequencing (NGS) to determine if this provides a more 
precise way of detecting low levels of leukemia (on the order of 1 cell in 106) that could be used 
predictively for relapse(59-61). Adding this testing to our current CD19/CD22 protocol can yield 
information on very low levels of MRD in our patients and help us prospectively and 
retrospectively analyze data acquired for these patients after CAR therapy.
1.5
PROTOCOL SUMMARY AND RATIONALE 
Most aggressive cancers eventually relapse or become refractory to current conventional 
treatments, necessitating the immediate development of new treatment modalities. The most 
recent advances in cancer therapy involve the development of new immune stimulating agents 
designed to target T-cells to cancer cells and initiated cell death signaling pathways. However, 
limitations to this type of immunotherapy include lack of tumor specificity, insufficient T-cell 
recruitment/numbers, and the existence of endogenous immunosuppressive agents which 
significantly attenuate or altogether block T-cell activity.
Chimeric Antigen Receptor (CAR) expressing T-cells is a new therapy wherein a patient’s own 
T-cells are harvested and subsequently genetically modified in order to target cell surface 
antigens on specific cancer cells. In addition to their specificity, these CAR T-cells can be 
modified to be highly proliferative and possess the ability to negate immunosuppressive 
mechanisms making them ideal agents against highly aggressive cancers.
Specific to this study, bivalent CARs expressing both CD19 and CD22 will be utilized in order 
to avoid the immune escape that occurs when only a single antigen is targeted.
1.5.1
Clinical Trial Update on CD19/CD22 CAR T cells
As of September 2022, 26 patients with B-cell acute lymphoblastic leukemia (B-ALL) and 2 
patients with B-cell non-Hodgkin lymphoma (NHL)have been treated on this study across three 
different dose levels and the results of the ALL cohort are described below. 
Fifteen (58%) of those with ALL developed cytokine release syndrome (CRS), with 3 (11.5%) 
having ≥ grade 3 CRS and all were effectively treated with supportive care, and some patients 
required administration of tocilizumab and/or steroids. Additionally, of the 26 patients treated, 
only 2 experienced neurotoxicity (grade 3) which was reversible with systemic steroids and 
intrathecal hydrocortisone. 
Importantly, 17/26 patients with B-ALL had complete remission of their disease. Based on the 
results to date, dose level 3 is being utilized in the expansion pase of the study, as it has a 
tolerable side effect profile and is associated with anti-leukemia response(62).

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1.5.2
Dose Escalation
The experience to date with CD19 CAR and the POB NCI experience thus far with CD22-CAR 
trials is that dose level 1 x 106 transduced CAR T cells/kg is an effective dose. Given that this is 
a new CAR construct, our proposal is to start as a lower dose level at 3 x 105 transduced CAR T 
cells/kg. 
1.5.3
Rationale for Amendment, version date 01/11/2020
Based on the experience to date (n=11), this CAR T-cell construct is well-tolerated but at the 
current dose levels being utilized, we are seeing limited expansion, persistence and efficacy. 
Although initial dose escalation was planned using our prior CAR T-cell experiences, to further 
explore the functionality of this construct, we would like to add an additional dose level on this 
trial.  For several CD19 CAR-T cell constructs, including the FDA approved construct, early 
CAR-T cell expansion and prolonged B-cell aplasia > 6 months was associated with complete 
responses and long-term CAR persistence and response. Thus, we propose to add an additional 
dose level, DL 4: 1 x 107 transduced T cells/kg.
Thus far, no subject has experienced DLT at any dose level and cytokine release syndrome 
(CRS) has been limited [DL1 (3 x 105 transduced T cells/kg (n=4); DL2: 1 x 106 transduced T 
cells/kg (n=4); DL3: 3 x 106 transduced T cells/kg (n=3)] and only 2 of 11 subjects has had  > 
grade 2 CRS, both of whom had full recovery. 
We hypothesize that a higher dose level could safely be administered with a potential to optimize 
CAR T-cell persistence and efficacy and that this dose level can be adequately manufactured. 
Additional dose-escalations are not planned due to concerns for dosing feasibility.
In CD19 CAR treated patients, disease burden correlated with toxicity profile and severity of 
CRS; patients with higher disease burden had higher grade CRS(18, 19, 63). Thus, we have had 
minimal clinically significant cytokine release syndrome (CRS) at DL1-DL3, with only 2/11 
patients treated having > grade 2 CRS.
1.5.4
Rationale for Amendment, version date 09/08/2020
Protocol update: (as of 9/15/20) A total of 17 patients have been enrolled on study, and 15 
patients have been treated to date (one patient had intercurrent illness that precluded treatment, 
and one additional patient has yet to be infused). Amongst the 17 patients, 1 patient has B-cell 
lymphoma, and the others have B-cell ALL.
Table 1: Enrollment by Dose Level, Response, and Toxicity Summary
Dose level 
(Dose 
transduced 
CAR T 
cells/kg)
Enrolled (n)
Previous 
CAR 
therapy n, 
(%)
DLT (n)
CR (n, % CR 
rate)
Persistence 
of 
Circulating 
CAR-T cells 
at 2 months 
(n, %)
1 (3 x 10e5)
4
4, (100%)
None
0
None

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Abbreviated Title: CD19/CD22 T-cell in Peds
Version Date: November 19, 2024
Dose level 
(Dose 
transduced 
CAR T 
cells/kg)
Enrolled (n)
Previous 
CAR 
therapy n, 
(%)
DLT (n)
CR (n, % CR 
rate)
Persistence 
of 
Circulating 
CAR-T cells 
at 2 months 
(n, %)
2 (1 x 10e6)
4
1, (25%)
None
2 (50%)
1 (25%)
3 (3 x 10e6)
9*
1, (14%)#
1, (14%)#
5 (71.4%)#
None
*2 patients have not been treated. # denominator is 7 patients treated at dose level 3. Dose 
level 3 was expanded to treat at least 6 patients due to DLT as described below. No additional 
DLTs were seen. DL3 will now be used for expansion phase of trial..
One subject has experienced DLT at dose level 3 (3x106 transduced T cells/kg) in the form of 
grade 3 neurotoxicity which manifested as delirium/confusion and altered mental status. This 
subject was treated with steroids and had rapid reversal of neurotoxicity. Dose level 3 has now 
been expanded to treat at least 6 patients. Cytokine release syndrome (CRS) >grade 3 remains 
limited [DL1 (3 x 105 transduced T cells/kg (n=4); DL2: 1 x 106 transduced T cells/kg (n=4); 
DL3: 3 x 106 transduced T cells/kg (n=7)] with only 2 of 15 subjects having had  > grade 2 CRS, 
both of whom had full recovery.
Thus, based on the response rate at dose level 3, and limited toxicity profile, we will use dose 
level 3 in the expansion phase of the trial.
Additional changes in this amendment include:
•
Increasing the age limit to 35: The current adolescent and young adult (AYA) definition 
used by the NCI (and widely accepted in the oncology community) includes patients up 
to 39 years of age. We will target an age <35 years old as many young adults are 
relapsing with B cell malignancies, that are biologically/ genetically similar to pediatric B 
cell malignancies, and may be amenable to treatment with CAR T-cell therapy, however 
are not eligible to receive the FDA approved product which is currently limited to those < 
25 years of age. All prior POB HSCT protocols have treated patients up to 35. The 
pediatric oncology branch has expertise in treating AYA patients with refractory 
malignancies and has gained significant experience and comfort in treating this young 
adult population with CAR T-cell therapy. 
•
Addition of an option to administer oral mesna and oral hydration for patients receiving 
outpatient lymphodepleting chemotherapy. The option to give oral supportive care 
(hydration and mesna) is considered standard of care and a well-established practice in 
the Children’s Oncology Group Consortium Supportive Care Guidelines.  
•
Increasing the time from donor lymphocyte infusion (DLI) to enrollment/treatment on 
study with CAR T cells due to a recent incident in a patient where the patient received 
DLI 4 weeks prior to enrollment and developed graft-versus-host-disease (GVHD). The 
GVHD is primarily attributable to DLI, however, it is possible that CAR T-cells could 
have contributed to triggering the GVHD event.

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1.5.5
Rationale for Amendment, version date 05/17/2021
1.5.5.1
Modify Dosing Calculation Practices in Obese Patients
Based on our ongoing efforts in CAR T-cell therapy in children and young adults, and both the 
1) recent increase in the upper age limit and 2) consideration of an non-responding obese patient 
recently treated on a parallel CAR T-cell trial (and review of our own data), we have made the 
decision to revise our current protocol guidance for dosing in obesity. 
To date, there are no well-established guidelines for CAR T-cell dosing in obesity, and more 
importantly, there has been no clear evidence for increased toxicity with CAR T-cells based on 
obesity, however, dose-dependent responses and anti-leukemia efficacy has been well-
established by our team and others.  Our current practice (established in 2012) incorporates 
dosing on a per kg/basis with dosing/weight adjustments for obesity for a BMI > 30. However, in 
review of our practices and national obesity metrics, we believe that this guideline warrants 
revision. 
Based on both institutional and national practices, consideration of CAR T-cell dosing 
limitations, and to more appropriately account for pediatric and adult obesity, we will be making 
the following changes: 
•
Maximum cell dosing will be capped at 100 kg weight (currently there is no cap on 
weight)
•
Cell dose adjustments for obesity will be made for BMI > 35
o
Practical weight (as per our current protocol) will be utilized for dose-adjustments in 
obesity
o
IBW for pediatric patients will be used for pediatric based dosing and obesity 
considerations (this was previously missing in our protocol)
By setting a dose cap, based on weight, incorporating pediatric IBW considerations and setting 
dose adjustment parameters for a BMI > 35, we believe these changes will be safe, account for 
CAR T-cell dosing feasibility and also optimize dosing in obese patients.
1.5.5.2
Utilization of ASTST consensus criteria for CRS grading
Protocol will be clarified to only use ASTCT consensus criteria (54) for CRS for grading. Prior 
Lee will not be used and any CRS grading per Lee (22) in the initial cohort of patients will be 
reconciled and re-graded per ASTCT. This will allow for harmonization of CRS grading across 
constructs.
1.5.5.3
Inclusion of patients with isolated CNS disease and/or CNS3 disease
With experience in 18 subjects on this protocol, only one subject developed reversible, grade 3 
immune-effector cell associated neurotoxicty syndrome (ICANS) and no subjects experienced 
irreversible ICANS (i.e. cerebral edema). In comparison to both institutional(20) and 
extramural(63-65) experience with the anti-CD19(19, 66) and anti-CD22 CAR(53, 67), the 
neurotoxicity profile of this particular CAR appears to be well tolerated. To date, 3 patients on 
this protocol have enrolled with active CNS disease (2 patients with flow cytometric CNS 
disease and 1 patient with CNS2 disease), and all subjects tolerated the infusion without any 
severe ICANS. Additionally, anti-leukemia activity in the CNS was seen and CAR T cell 
trafficking to the CSF space has been demonstrated, with a median %CAR T cells at day 28 of 

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Abbreviated Title: CD19/CD22 T-cell in Peds
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1.1% (range:0-49.7%) Based on the experience to date on this current protocol, the POB’s prior 
experience with treatment and management of patients with active CNS involvement by disease 
(CD19 CAR, 12-C-0112), (CD22 CAR, 15-C-0029), incorporation of prospective neuro-
cognitive testing and knowledge of trafficking of CAR cells to the cerebrospinal fluid, we are 
proposing to allow for the inclusion of patients with isolated CNS disease and/or CNS3 disease 
at dose level 3 (3 x 106 CAR T cells/kg) to explore toxicity and response.
1.5.5.4
Allow for reinfusion of CAR T cells in patients with loss of B-cell aplasia and/or loss of 
CAR T cell persistence
Although CD19 and CD22 CAR T cells have a high response rate in children and young adults 
with R/R B-ALL, 40-50% of patients relapse post CAR infusion(18, 53, 63, 68, 69). B-cell 
aplasia is a surrogate marker of ongoing CAR T cell activity and persistence, and some studies 
have demonstrated that early loss of B-cell aplasia, generally defined < 6 months post infusion, 
can be useful in predicting a patients’ risk of CD19+ relapse(63, 68)(Pulsipher, data presented at 
TCT virtual meeting 2021). Indeed, one study demonstrated that loss of B-cell aplasia adversely 
affected the risk of CD19+ relapse, with a hazard ratio 34 (95% CI, 2.1-552; p=0.01). Loss of 
CAR persistence has also been correlated with relapse(63). Reinfusion of CAR T cells has been a 
strategy to try and maintain more durable remissions, with some demonstrated success(68, 70). 
Indeed, there is an ongoing phase 2 clinical trial to assess efficacy and safety of administration of 
tisagenlecleucel reinfusion in patients who experience loss of B-cell aplasia 
(NCT04225676)(71). Additionally, in our current and previous POB CAR T cell trials (CD19 
and CD22), we have demonstrated safety in reinfusing patients who relapse post-initial infusion. 
Thus, based on the experience to date, we are proposing to allow for reinfusion of CD19/CD22 
CAR T cells in patients with loss of B-cell aplasia, and/or loss of CAR T cells as measured by 
flow cytometry (defined in section 3.11). Patients will receive the same dose level of CAR T 
cells as their initial infusion, and will receive increased lymphodepleting chemotherapy as 
outlined in section 3.9.2.2. In cases where a subject is reinfused for loss of CAR T cells or loss of 
B-cell aplasia (e.g without evidence of relapsed, active disease), we will monitor duration of 
engraftment of CAR T cells and/or recurrence of B-cell aplasia as a separate event as time from 
the reinfusion. These subjects will continue to have duration of leukemia/lymphoma response 
captured from the time of initial infusion.
1.5.5.5
Increase the age limit to be consistent with other POB CAR trials and with current 
adolescent and young adult (AYA) definition
The age limited has been increased to 39 to keep consistent with other POB CAR trials and be 
consistent with current AYA definition which includes patients up to 39 years of age.
1.5.6
Rationale for Amendment, version date (09/16/2022)
1.5.6.1
Addition of exploratory objectives
Additional exploratory objectives evaluating the microbiome and metabolism have been added. 
Please see section 1.7.9 and 1.7.10 for further information. 
1.5.6.2
Discontinuation of prospective neurocognitive testing in all patients, with the exception 
of patients with isolated CNS disease. 
The rationale for removal of neurocognitive testing is that this exploratory endpoint has been 
completed and recently published (62). In summary, in the 20 patients treated and included in the 

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Abbreviated Title: CD19/CD22 T-cell in Peds
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neurocognitive endpoint, 17 of 20 patients completed pre- and post-infusion assessments and a 
majority of patients had stable or improved neurocognitive scores in the 5 domains tested.  Of 
the 146 paired test scored from patients, 132 (90.4%) paired test scores were stable or improved 
over time. Additionally, comparison of mean scores on neurocognitive measures pre- and post-
infusion demonstrated stable or improved mean scores in all patients. 
As of September 2022, we have seen minimal neurotoxicity, and will continue to closely monitor 
all subjects for neurotoxicity with appropriate evaluations and interventions in place. See 
Appendix B 2:  Neurotoxicity Assessments Calendar for revised neurologic evaluations.  
1.5.7
Rationale for Amendment (05/08/2023)
1.) Addition of exploratory objective evaluating the role for siltuximab in management of 
CRS.
Please see section 1.7.11 for further details.
2.) Addition of alternate lymphodepletion regimen due to a national shortage of fludarabine.
Fludarabine and cyclophosphamide are the most commonly used lymphodepletive preparative 
regimens used prior to CAR T-cell infusion. As of May 2022, fludarabine has been reported to 
be in short supply across the United States. In the event that fludarabine is not available or there 
is limited supply, we propose to use pentostatin and cyclophosphamide as lymphodepletion prior 
to CAR T-cell infusion. 
Pentostatin is a purine analog that is noted to have lymphocyte-depleting properties(72-76).  
Pentostatin has previously been shown to deplete lymphocytes including multiple T-cell subsets 
within a week of administration(77).  The combination of pentostatin and cyclophosphamide has 
previously been shown to be safe when used to treat chronic lymphocytic leukemia (CLL)(72, 
76). One patient was treated with pentostatin and cyclophosphamide prior to administration of 
autologous anti-CD19 CAR T cells(78),  The transferred T cells proliferated vigorously and 
persisted at high levels for several months(78), The patient obtained a prolonged complete 
remission(78). This group also utilized pentostatin/cyclophosphamide as one of 3 different 
lymphodepletion regimens prior to CD19 CAR T-cell infusion in 14 patients with CLL and 
reported that 8/14 patients responded, although there is no detailed information regarding  those 
who received pentostatin(79).  Pentostatin has been safely used after allogeneic stem cell 
transplantation to treat graft-versus-host disease(75).  Pentostatin is generally thought to cause 
less myelosuppression relative to lymphocyte depletion when compared to other agents such as 
fludarabine(72, 74, 76).   Pentostatin synergizes with the alkylating agent cyclophosphamide to 
cause lymphocyte depletion in mice, and pentostatin has also been shown to suppress T cell 
function in T cells that are not depleted(74, 80). Recently published work out of NIH by 
Dimitrova et al demonstrated that pentostatin/cyclophosphamide was a well tolerated reduced 
intensity conditioning regimen for pediatric transplant patients with primary 
immunodeficiencies, and that patients did not exhibit increase in infections and had low 
incidence of organ toxicity(81). 
We propose to utilize a lower dose of pentostatin of 2mg/m2/dose as this dose was used in 
patients with hairy cell leukemia whom were deemed high risk patients (those who had 
infections or had myelosuppression at presentation)(82) and most patients who will enroll on this 
trial have myelosuppression due to prior therapies. This modest dose to the current 

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cyclophosphamide backbone offers synergy without increased risk of toxicity. See section 3.9.2 
for regimen details. If and when pentostatin is utilized, we will specifically evaluate outcomes in 
relationship to CAR T-cell toxicity, efficacy and CAR T-cell expansion. 
1.6
PEDIATRIC ENROLLMENT
The first patient treated in the first cohort will be greater than 18 years of age to provide an initial 
safety evaluation prior to administration in pediatric patients. Safety data from adult patients 
treated on the Stanford study “Phase 1 Dose Escalation Study of CD19/CD22 Chimeric Antigen 
Receptor (CAR) T Cells in Adults with Recurrent or Refractory CD19/CD22-expressing B Cell 
Malignancies” (PI: Crystal Mackall, MD), information regarding any toxicity will be shared and 
may similarly inform dose escalation safety data on this study for the initial treatment of 
pediatric patients on this trial. Pediatric patients will only be treated after at least 1 patient ≥ 18 
years of age or older will undergo investigational cellular therapy without DLT (observed for 28 
days after infusion) prior to treating a pediatric patient (< 18 years of age).  
1.7
CORRELATIVE STUDIES BACKGROUND
CAR T cell therapy targeting a single tumor associated antigen has mediated striking remissions 
in B cell leukemia and lymphoma. The clinical experience to date has demonstrated that anti-
leukemic effects are associated with CAR T cell expansion(19),(83) and that sustained remission 
is associated with CAR T cell persistence(84). In patients who have relapsed in the presence of 
persistent singular CD19 specific or CD22 specific CAR T cells, relapse has often been 
characterized by CD19 dim/negative or CD22 dim/negative phenotypes respectively. The 
complex interplay of tumor, T cell and intrinsic CAR properties that influence these outcomes 
are not well understood. We aim to utilize this safety study as an opportunity to collect 
correlative data that will permit extensive study of both the B cell and T cell compartment prior 
to and following CAR T cell therapy.  We aim to integrate multi-dimensional technologies to 
permit complex analyses of the apheresis product, the CAR T cell product pre-infusion and in 
vivo expanded CAR T cells following antigen encounter. We additionally aim to investigate 
properties of B cell tumors that render them susceptible to CAR T cell cytotoxicity and study 
physiologic and malignant B cell remodeling under the pressure of multi-targeted CAR therapy.
1.7.1
Factors Impacting Loss of CAR T cells 
Persistence of CAR T cells is associated with superior anti-leukemia effects in the setting of 
CD19-CAR T cell therapy for leukemia.  We hypothesize that there are three distinct causes of T 
cell loss following CD19/22-CAR T cell therapy.  First, in a subset of patients, there is poor 
CAR T cell expansion following infusion of a product that appears to meet appropriate release 
criteria.  We hypothesize that such products can be identified by the presence of exhausted or 
terminally differentiated cells that lack progenitor capacity.  To explore the potential to identify 
such products a priori, we will analyze apheresis samples and manufactured products to 
enumerate the frequency of naïve, T stem cell memory, T central memory and T effective 
memory subsets.  We will also analyze apheresis and manufactured products for the presence of 
markers of T cell exhaustion including PD-1, Tim3 and LAG-3. Phenotypes will be correlated 
with the degree of expansion following CAR T cell infusion.  
Second, we hypothesize that a subset of patients will undergo efficient early T cell expansion but 
will demonstrate loss of CAR-T cell persistence associated with the acquisition of a terminally 
differentiated phenotype and/or characteristics of T cell exhaustion.  To test this, we will 

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Abbreviated Title: CD19/CD22 T-cell in Peds
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evaluate CAR expressing T cells in vivo following adoptive transfer to identify characteristics 
associated with poor persistence.  These phenotypic analyses will include flow cytometry and 
mass cytometry with a goal of identifying T cell phenotypes associated with poor persistence in 
vivo.  We will also undertake epigenetic analyses to analyze correlations between T cell 
phenotype, persistence and enhancer profiles.  Where possible, we will also compare the 
phenotype of cells harvested from blood, bone marrow, CSF and lymphoma to analyze whether 
the tissue microenvironment has substantial impact on T cell exhaustion, phenotype or function.  
Finally, we hypothesize that a subset of patients lose their CAR T cell populations as a result of 
immune rejection.  To test this, we will analyze for the presence or development of anti-CAR 
mediated T cell responses using cell based assays, as well as overlapping peptide libraries to 
localize the targets of anti-CAR reactivity. 
1.7.2
Impact of Persistent CD19/22 Immune Pressure on Malignant and Normal B Cell 
Differentiation
CD19 and CD22 are acquired during the process of normal and malignant B cell differentiation.  
Persistent immune based pressure targeting these two antigens has the potential to induce 
profound changes on both normal and malignant B cell differentiation.  In this study, we will use 
mass cytometry, flow cytometry, exome sequencing, RNAsequencing and ATAC-Seq to monitor 
changes in the normal and malignant B cell differentiation in the presence of persistent CAR T 
cells targeting these antigens.  We will explore whether this dual targeted therapeutic is capable 
of inducing loss of either or both antigens in malignant cells and whether such antigen loss B-
ALL cells is associated with a particular differentiation state, a particular genotype and/or are 
associated with increased or diminished fitness as evidenced by clinical behavior, or where 
possible growth patterns ex vivo.  Similar analyses will focus on patients with remission 
marrows, analyzing whether normal B cell development can proceed in the absence of CD19 
and/or CD22 subpopulations.  This will provide a novel opportunity to characterize the impact of 
CD19 and/or CD22 loss on normal lymphoid and/or myeloid cells development.
1.7.3
Utility of minimal residual disease assessment
A reliable biomarker that detects disease before it is evident clinically or on imaging offers 
potential to improve long-term disease control and survival. Necrosis and apoptosis of 
lymphoma cells lead to release of tumor DNA in blood circulation(85), DNA fragments in the 
blood plasma of cancer patients: quantitations and evidence for their origin from apoptotic and 
necrotic cells(85). Next-generation sequencing and high-throughput technology can non-
invasively detect and quantify the circulating free DNA (cfDNA)(86). The VDJ immunoglobulin 
genes contain unique sequences that are markers of clonality(87). These clonal markers can be 
used to assess MRD after the treatment and have been shown to prognostic value in DLBCL 
post-treatment surveillance(86) and other lymphoid malignancies(88),(89).
The role of MRD testing and cfDNA assessment in patients treated with CAR-T cells has not 
been well studied. In this study, we will correlate cfDNA assessment with marrow flow 
cytometry to identify the timing of relapse identification using these two approaches.

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Abbreviated Title: CD19/CD22 T-cell in Peds
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1.7.4
Explore the level CD19/CD22 surface expression and CD19/CD22 site density on 
leukemic blasts and correlate with clinical response to CAR-T cells
Based on preliminary experience in anti-CD22 and anti-CD19 CAR therapy, there does appear to 
be a threshold for CD19/CD22 antigen expression that is needed in order to effectively target 
leukemic blasts. In this study, CD19/CD22 expression and site density at baseline and at the first 
restaging will be performed as an optional evaluation, when samples are available, and evaluated 
at the National Cancer Institute (Flow Cytometry Lab: Dr. Maryalice Stetler-Stevenson) where 
there is the expertise and ability to characterize CD19, and particularly CD22 expression. In 
parallel, exome sequencing and RNA sequencing (Shern lab POB) will be performed to analyze 
the correlation in observed changes at the protein level with genetic and transcriptional changes 
at the antigenic locus.
1.7.5
Use of endothelial cell and coagulation markers to evaluate for thrombotic events
The endothelium has a crucial role in maintaining hemostatic balance by synthesizing, storing, 
and releasing many proteins that have opposing roles. For instance, it is responsible for 
vasoconstrictor, vasodilator, anticoagulant, and procoagulant proteins and when damage occurs 
to the endothelial cell, the delicate balance can be disrupted(90). Few complex cases of 
hematologic diathesis have been seen in patients treated with CAR T cell therapy. By adding 
additional research tests to evaluate endothelial cell markers, platelet activation, and fibrinolysis 
inhibitors, we will be able to study if certain biomarkers can play a role in predicting which 
patients treated with CAR T cells will have thrombotic or micro-thrombotic disease. Some of 
these tests have been shown to be predictive of thrombotic events in other patient populations. 
For instance, in cases of veno-occlusive disease, hepatic venous endothelial dysfunction is 
thought to be an inciting event that causes thrombosis, with low levels of activated protein C, and 
increased secretion of PAI-1 contributing to thrombosis(91). Additionally, prothrombin fragment 
1+2 along with D-dimer was shown to be increased in patients with venous thromboembolisms 
versus those without (P<0.001)(92). Furthermore, there is recent evidence that endothelial 
activation may be involved in the toxicity profile(93), particularly neurotoxicity and that this 
may bear resemblance to HUS/TTP pathophysiology. These research studies can potentially 
yield important information that can have therapeutic implications for our patients and enhance 
our understanding of the mechanism related to CAR or cytokine mediated hematologic toxicities.
1.7.6
Retrospective Grading of CRS as per the newly established ASTCT CRS Consensus 
Grading COMPLETED
In an effort to standardize comparability in toxicity profiles across various CAR constructs and 
targets, there has been a recently established working group which has published consensus 
guidelines on the grading of CRS(54). Prior to this effort, there were multiple CRS grading 
criteria that were used, that make it difficult to determine comparability. At the NCI, we have 
always used the initial criteria that were developed and published by our NCI colleagues, in 
collaboration, with other institutes. However, to more uniformly inform the field, we will now 
grade CRS by the newly established guidelines, which will be put in our follow-up manuscript. 
These new guidelines will be used in conjunction with our current treatment algorithm which 
have been well established based on our experience to date. All patients on this trial to date have 
had both Lee and ASTCT CRS grading performed. 

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1.7.7
To explore apheresis and CAR- T cell product characteristics that may be associated with 
clinical outcomes (e.g., CAR T-cell persistence, toxicity and/or efficacy) 
With significant interpatient heterogeneity and realization of the impact of manufacturing 
changes on CAR T-cell related outcomes—including toxicity, efficacy and CAR T-cell 
persistence, this aim is to retrospectively evaluate apheresis and CAR T-cell product 
characteristics. Remaining products that are not used for clinical purposes will be retrospectively 
and prospectively analyzed utilizing multifactorial analysis to evaluate characteristic of the 
product that may correlate with outcomes. Analysis will be primarily performed in the Taylor 
Lab (POB), and in the CCE. Data will be reviewed in the context of clinical outcomes.
1.7.8
To explore CAR T-cell expansion by T-cell subsets and immunophenotypic evaluation of 
markers of T-cell activation and/or exhaustion
Characterization of the immunophenotype of CAR T-cell expansion will be informative to 
correlate with CAR T-cell persistence and/or toxicity and has not been well explored. We will 
incorporate systematic analysis of CAR T-cell profiling to look at characteristics of the CAR T-
cell, including T-cell subsets and immunophenotypic profiling to correlate with clinical 
outcomes.
1.7.9
Gut Microbiome Assessment of Patients Undergoing CAR-T Cell Therapies 
The human gut microbiome, or community of microorganisms that are found in the intestines, is 
implicated in the etiology, progression and response to treatment in several different disease 
processes including obesity, inflammatory diseases and cancer(94). Specifically in cancer, the 
gut microbiome has a role in: 1) tumor initiation and progression, both through a direct effect on 
tumor cells and indirectly through manipulation of the immune system; 2) determining a 
response to cancer therapies and to predict progression and survival; and, 3) therapy, with 
modulation of the microbiome being able to potentiate the effect of certain immunotherapies and 
decrease toxicity(95, 96). There is currently minimal human data regarding the role of the gut 
microbiome in CAR T cell therapy. Murine models show microbial short chain fatty acids 
improve anti-tumor activity of specific CAR T cells and that modulation of the microbiome may 
produce an increased anti-tumor effect(97, 98). One adult study (unpublished) showed an 
enrichment in certain gut bacterial taxa correlating with clinical response and toxicity, and there 
have been no pediatric studies looking at the role of the microbiome. 
Within this current CAR T cell treatment protocol, we propose a pilot observational microbiome 
assessment of patients undergoing CAR T cell therapy at the NIH Clinical Center through stool 
collection to assess how the gut microbiome may be associated with a) cytokine release 
syndrome, b) neurotoxicity, c) clinical response, and d) infection. Results of this study may help 
give a more complete understanding of response and complications of CAR T cell therapy and 
possibly identify microbiome therapeutic targets to improve response rates and decrease 
complications. We plan on collecting stool samples pre lymphodepleting (LD) chemo, post LD 
and pre-CAR-T cell infusion (optional) as well as post- timing differing with and without an 
occurrence of CRS as well as with any relevant clinical event. The goal of this exploratory 
objective is to evaluate the gut microbiome in patients receiving CAR-T therapy and correlate 
with cytokine release, neurotoxicity, infection, antibiotic use, and clinical response.

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1.7.10 Metabolomic Analysis in Patients Undergoing CAR-T Cell Therapies
Over the last decade, growing evidence has accumulated to show the importance of metabolism 
on immune responses(99). Metabolomic analysis also emerged as a major tool in the field of 
immunotherapy and immunopathology. Metabolomic profiles integrate host and microbiota-
derived metabolites as well as xenobiotics or nutrients factors and have been associated with 
high impacts on checkpoint inhibitor therapy, graft versus host disease, and auto-immune 
diseases(100-102). Preclinical studies on CAR-T cells highlighted the important relationship 
between T-cell metabolic fitness, microenvironment metabolites levels and anti-tumor 
function(103, 104). Importantly, the question of how metabolite levels influence efficacy and 
toxicity in pediatric patients treated with CAR-T cell therapy remains unanswered. 
This study will measure metabolite levels in patient plasma/urine metabolites levels as a function 
of CAR-T cell therapy in a targeted and untargeted manner, with the goal of defining profiles 
associated with efficacy (complete response, duration of response, overall survival), toxicity 
(cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, 
hemophagocytic lymphohistiocytosis-like syndrome), CAR expansion and persistence. Targeted 
analysis will focus on redox balance (ascorbate, NAD(H), FAD(H), glutathione), amino-acids 
(arginine, tryptophane, glutamine, methionine), nucleoacids (ATP, adenosine), TCA cycle 
metabolites, hepcidin, Acteyl-CoA and lipids. To this end, peripheral blood and urine samples 
will be obtained from patients at the indicated time points pre- and post-CAR-T cell therapy. All 
samples will be prepared under the direction of Dr. Naomi Taylor and will then be evaluated for 
the metabolites indicated above. The goal of this analysis is to evaluate how metabolite levels 
influence efficacy of CAR-T cells, and toxicity in pediatric patients treated with CAR-T cell 
therapy. 
1.7.11 To evaluate the efficacy of siltuximab in treatment of cytokine release syndrome
CRS is the most commonly seen toxicity in CAR T-cell therapy, and it occurs as a result of non-
specific immune activation, which is closely related to pro-inflammatory cytokines, in specific 
IL-6. In the global registration trial using tisagenlecleucel, tocilizumab (an IL-6 receptor 
antagonist) was administered in 39% of patients, and it was noted to reverse CRS, and did not 
affect clinical efficacy, namely CAR T-cell expansion, complete remission rates, or persistence 
of CAR T-cells(63).  Tocilizumab received FDA approval in 2017 for treatment of CAR T-cell 
related CRS(105). However, anecdotal evidence has suggested that neurotoxicity or ICANS may 
worsen or can develop after toclilizumab administration due to transient rise in serum IL6 that 
results in decreased clearance via endocytosis by the antagonized IL6R(22, 106-109). Indeed 
patients treated on our CD19-28z CAR trial who received tocilizumab had significantly elevated 
levels of CSF IL-6 on D28 as compared to those that did not receive tocilizumab and a pre-
clinical model in a rhesus macque demonstrated that IV tocilizumab had poor CNS penetration 
(107, 108).  
During the COVID-19 pandemic, an international shortage of tocilizumab prompted medical 
providers to use alternative agents such as siltuximab, to treat COVID-19 and demonstrated that 
siltuximab was well tolerated and an effective alternate that reduced CRS associated 
inflammation and COVID-19 mortality(110-112).  In an effort to find additional therapies to 
optimize CAR T-cell toxicity profiles, several ongoing studies are now evaluating the use of 
siltuximab, an IL-6 antagonist that directly binds free IL-6, for prevention or treatment of CRS or 

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ICANS (NCT04975555, NCT05665725). Recently presented data demonstrated that 5/6 patients 
who received siltuximab for CRS had resolution of CRS of 1 hour (range 1-13 hrs) from first 
siltuximab infusion, and only 1 patient required rescue tocilizumab. Additionally, 3/4 patients 
with ICANS had resolution of ICANS with siltuximab and corticosteroid treatment(113).  
Siltuximab will be used as first line CRS management in both pediatric and adult participants 
treated with CD19/CD22 CAR T cells. Dosing is based on the FDA approved dose for adults 
which is 11mg/kg. 
Based on the limited experience with use of siltuximab in pediatric patients receiving CAR T-
cells, this dose appears to be well-tolerated with potential for benefit in the management of CRS, 
particularly in the setting of neurotoxicity. Specifically, on the multisite CAR T cell trial 
targeting GD2 for patients with relapsed/refractory osteosarcoma or neuroblastoma 
(NCT04539366), 3 pediatric participants have received siltuximab at 11mg/kg (2 of whom 
received siltuximab at the NIH CC) for CRS without notable side effects (PI: Kaplan, personal 
communication). On several phase I/II CAR T cell studies treating pediatric and young adult 
patients with relapsed/refractory hematologic malignancies, physicians at the Children’s Hospital 
of Philadelphia and St. Jude Children’s Research Hospital are also giving siltuximab at 11 mg/kg 
without notable complications (PIs: Grupp, Talleur, personal communication). 
On this current trial, 19/23 patients treated at the current dose level (3x10^6 transduced CAR T-
cells/kg) have achieved complete remissions. Six patients (26%) treated at this dose level 
experienced ≥ grade 2 CRS and received tocilizumab as first line therapy for CRS. Additionally, 
3 patients experienced grade 3 ICANS, 2 of whom received tocilizumab  prior to the 
development of ICANS. All patients recovered from acute CRS and ICANS toxicities. 
Given the established safety profile of this CD19/CD22 CAR construct, the opportunity to 
prospectively study additional IL6 directed agents, including those which may have the potential 
to decrease rates of neurotoxicity (as siltuximab directly binds IL6, theoretically decreasing the 
ability of high levels of IL6 to cross the blood brain barrier) serves to expand the arsenal of 
medications which can be used to treat CRS. A treatment algorithm has been developed whereby 
standard agents such as tocilizumab and/or steroids will be employed if participants continue to 
have worsening or refractory CRS/ICANS after siltuximab administration (see Figure 9 in 
protocol), to prevent more severe complications. Treatment will be as per Appendix D: 
Guidelines for Grading and Management of Suspected Cytokine Release Syndrome, Figure 9.
2
ELIGIBILITY ASSESSMENT AND ENROLLMENT 
2.1
ELIGIBILITY CRITERIA
Study subjects with CD19+CD22+expressing B cell malignancies who have relapsed or are 
treatment refractory may enroll as defined by the following inclusion and exclusion criteria.
2.1.1
Inclusion Criteria
2.1.1.1
Diagnosis
Participant must have a B cell ALL (inclusive of CML with ALL transformation) or lymphoma 
and must have relapsed or refractory disease after at least one standard chemotherapy regimen 
and one salvage regimen. In view of the PI and the primary oncologist, there must be no 
available alternative curative therapies and subjects must be either ineligible for allogeneic stem 

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cell transplant (SCT), have refused SCT, recurred after SCT, or have disease activity that 
prohibits SCT at the time of enrollment. Participants who have undergone autologous SCT will 
be eligible, and participants that have undergone allogeneic SCT will be eligible if, in addition to 
meeting other eligibility criteria, they have no evidence of GVHD and have been without 
immunosuppressive agents for at least 30 days. Participants with Philadelphia chromosome + 
ALL must have failed prior tyrosine kinase inhibitor. 
Participants must have measurable or evaluable disease at the time of enrollment, which may 
include any evidence of disease including minimal residual disease detected by flow cytometry, 
cytogenetics, or polymerase chain reaction (PCR) analysis. For those being considered for 
reinfusions, measurable or evaluable disease is not required at the time of reinfusion.
2.1.1.2
CD22/CD19 expression 
CD19 expression must be detected on greater than 15% of the malignant cells by 
immunohistochemistry or greater than 90% by flow cytometry. The choice of whether to use 
flow cytometry or immunohistochemistry will be determined by what is the most easily available 
tissue sample in each participant. In general, immunohistochemistry will be used for lymph node 
biopsies, flow cytometry will be used for peripheral blood and bone marrow samples. CD22+ B 
cell malignancy is required and CD22 expression levels will be documented when available, but 
a specific level of expression is not an eligibility requirement; it may be documented as positive 
or negative.
2.1.1.3
Age
Greater than or equal to 3 years of age (and at least 15 kg) and less than or equal to 39 years of 
age at time of enrollment (> 3 years to < 39 years).  NOTE: The first participant in each dose 
cohort must be ≥ 18 years of age.
2.1.1.4
Clinical Performance
Clinical performance status: Participants > 16 years of age: Karnofsky ≥ 50%; Participants < 16 
years of age: Lansky scale ≥ 50% (see Appendix A for conversion). Subjects who are unable to 
walk because of paralysis, but who are upright in a wheelchair will be considered ambulatory for 
the purpose of calculating the performance score.
2.1.1.5
Participants must have adequate organ and marrow function as defined below: 
leukocytes
>750/mcL*
platelets
>50,000/mcL*
total bilirubin
<2 X ULN (except in the case of subjects 
with documented Gilbert’s disease > 3x 
ULN)
AST(SGOT)/ALT(SGPT)
<10 X institutional upper limit of normal
creatinine
< the maximum for age listed in the table 
below
OR
creatinine clearance
>60 mL/min/1.73 m2 for participants with 
creatinine levels above institutional normal.
Age
Maximum Serum

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Abbreviated Title: CD19/CD22 T-cell in Peds
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(Years)
Creatinine (mg/dL)
≤ 5
< 0.8
6 to ≤ 10
< 1.0
>10
< 1.2
* if these cytopenias are not judged by the investigator to be due to underlying disease (i.e. 
potentially reversible with anti-neoplastic therapy); A subject will not be excluded because of 
pancytopenia ≥ Grade 3 if it is due to disease, based on the results of bone marrow studies.
2.1.1.6
Subjects with CNS disease are eligible, with exceptions as noted in the exclusion criteria 
2.1.2.2
2.1.1.7
Contraception
2.1.1.8
Individuals of child-bearing or child-fathering potential  (IOCBP or IOCFP) must be 
willing to practice birth control from the time of enrollment on this study and for 12 
months after receiving the preparative regimen for IOCBP and for 4 months after 
receiving the preparative regimen for IOCFP.
2.1.1.9
Cardiac function: Left ventricular ejection fraction ≥ 45% or fractional shortening ≥28%, 
and no clinically significant ECG findings
2.1.1.10 Pulmonary Function
2.1.1.10.1 Baseline oxygen saturation >92% on room air at rest 
2.1.1.10.2 Participants with respiratory symptoms must have a DLCO/adjusted > 45%. For 
children who are unable to cooperate for PFTs they must not have dyspnea at rest or 
known requirement for supplemental oxygen.
2.1.1.11 Ability of subject, parent(s)/guardian(s), Legally Authorized Representative (LAR), or 
Durable Power of Attorney (DPA) to understand and the willingness to sign a written 
informed consent document.
2.1.2
Exclusion Criteria
Subjects meeting any of the following criteria are not eligible for participation in the study:
2.1.2.1
Recurrent or refractory ALL limited to isolated testicular.
2.1.2.2
Subjects with radiologically detected active CNS lymphoma or isolated CNS disease 
which are eligible for definitive CNS directed radiation therapy will be excluded.;
2.1.2.3
Hyperleukocytosis (≥ 50,000 blasts/μL) or rapidly progressive disease that in the 
estimation of the investigator and sponsor would compromise ability to complete study 
therapy;
2.1.2.4
.Pregnant or nursing individuals.  

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2.1.2.5
Subjects will be excluded related to the following prior therapy criteria:
Systemic chemotherapy, anti-neoplastic investigational agents, or antibody based therapies ≤ 2 
weeks (6 weeks for clofarabine or nitrosoureas) prior to apheresis with the following 
exception:
•
No time restriction with prior intrathecal chemotherapy, steroid therapy, hydroxyurea or 
ALL maintenance type chemotherapy (vincristine, 6-mercaptopurine, oral methotrexate, 
or a tyrosine kinase inhibitor for participants with Ph+ ALL) provided there is recovery 
from any acute toxic effects.
Radiation therapy ≤ 3 weeks prior to apheresis with the following exception:
•
No time restriction with radiation therapy if the volume of bone marrow treated is less 
than 10% and the subject has measurable/evaluable disease outside the radiation 
window.
History of allogeneic stem cell transplantation prior to apheresis that meet the following criteria: 
•
Less than 100 days post-transplant 
•
Evidence of active graft-versus-host disease (GVHD)
•
Taking immunosuppressive agents within 30 days prior to apheresis.
•
Less than 6 weeks post donor lymphocyte infusion (DLI)
History of prior CAR therapy or other adoptive cell therapies prior to apheresis that meet the 
following criteria:
•
Less than 30 days post-infusion
•
Circulating CAR T cells (or genetically modified cells) >5% by flow cytometry in 
peripheral blood
2.1.2.6
HIV/HBV/HCV Infection:
•
Seropositive for HIV antibody. (Participants with HIV are at increased risk of lethal 
infections when treated with marrow-suppressive therapy. Appropriate studies will be 
undertaken in participants receiving combination antiretroviral therapy in the future 
should study results indicate effectiveness.) 
•
Positive for Hepatitis B surface antigen (HbsAG).
•
Evidence of active Hepatitis C (evidenced by detectable HCV RNA)
2.1.2.7
Uncontrolled, symptomatic, intercurrent illness including but not limited to infection, 
congestive heart failure, unstable angina pectoris, cardiac arrhythmia, psychiatric illness, 
or social situations that would limit compliance with study requirements or in the opinion 
of the PI would pose an unacceptable risk to the subject;
2.1.2.8
Second malignancy other than in situ carcinoma of the cervix, unless the tumor was 
treated with curative intent at least two years previously and subject is in remission;

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2.1.2.9
History of severe, immediate hypersensitivity reaction attributed to compounds of similar 
chemical or biologic composition to any agents used in study or in the manufacturing of 
the cells.
2.2
RECRUITMENT STRATEGIES
The following recruitment strategies will be employed to elicit potential candidates for this trial:
•
This study will be posted on NIH websites and on NIH social media forums. 
•
Listed on clinical trials.gov; 
•
Listed in PDQ; 
•
In addition, participants treated on other institutional trials who are eligible for 
participation will be offered participation in this study
Prior to distribution of any recruitment materials, such materials will be submitted to the IRB for 
review.
2.3
SCREENING EVALUATION
2.3.1
Screening activities performed prior to obtaining informed consent
Minimal risk activities that may be performed before the subject has signed a consent include the 
following: 
1. Email, written, in person or telephone communications with prospective subjects 
2. Review of existing medical records to include H&P, laboratory studies, etc.  
3. Review of existing MRI, x-ray, or CT images
4. Review of existing photographs or videos
5. Review of existing pathology specimens/reports from a specimen obtained for diagnostic 
purposes
A waiver of consent for these activities has been requested in section 11.6.4.
2.3.2
Screening activities performed after consent has been obtained
The following activities will be performed only after the subject has signed the consent for this 
study. Assessments performed at outside facilities or on another NIH protocol within the 
timeframes below may also be used to determine eligibility.
The following screening tests must be performed within 4 weeks of signing the consent unless 
otherwise noted. 
2.3.2.1
B-cell malignancy confirmation and CD19-CD22 expression 
Expression will be evaluated by immunohistochemistry or by flow cytometry in a CLIA 
approved laboratory and documentation at screening will be required (testing is permitted to be 
conducted at any time since most recent disease presentation). Confirmation of disease will be 
based on review of pathology reviewed and confirmed at NIH as feasible.
2.3.2.2
Participant Medical History
The participant’s complete history and a thorough review of medical records and by interview 
will be collected and recorded.  Concurrent medical signs and symptoms must be documented to 

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establish baseline severities. A disease history, including the month of initial diagnosis and list of 
all prior treatment, responses, and duration of response to the prior treatment also will be 
recorded.
2.3.2.3
Clinical Evaluation
A complete physical examination will be performed.  The exam will include general appearance 
of the participant, height and weight, vital signs, examination of the skin, eyes and ears, nose, 
throat, lungs, heart, abdomen, extremities, musculoskeletal system, and nervous system.  
Performance status will be scored on all subjects. Subjects under the age of 16 years will be 
scored according to the Lansky Scale. Subjects who are ≥16 years of age will be scored 
according to the Karnofsky Performance Status (See Appendix A). Body surface area (BSA) 
should be calculated at baseline.
2.3.2.4
Laboratory studies
•
Evaluation for HIV seropositivity to consist of ELISA and, if positive, confirmation by 
Western blot. The investigator, in the event of a positive finding, will make appropriate 
counseling available. 
•
Evaluation for Hepatitis B surface antigen (HbsAG) and anti-HCV antibodies. 
•
DTM Viral Markers (Transplant donor) and Rapid Plasma Reagin (RPR) will be drawn 
within 4 weeks of apheresis per DTM requirements. If apheresis has already been 
performed on another protocol, this testing will not be required.
•
Additional viral titers and PCR (e.g., CMV/EBV IgG/IgM) testing may also be done per 
PI discretion.
•
Creatinine clearance: A measured 24-hour urine creatinine clearance test may be 
performed if the serum creatinine is elevated, and the measured value will be recorded in 
the CRF and may be used to qualify the subject for study participation.
•
β-HCG serum or urine pregnancy test on all IOCBP.  
•
Peripheral blood CD3 count obtained by TBNK or PID panel
•
PT/PTT
2.3.2.4.1 General Tests: The following will be obtained during the screening process:
•
Chemistries: Sodium (Na), Potassium (K), Chloride (Cl), Total CO2 (bicarbonate), 
Creatinine, Glucose, Urea nitrogen (BUN), Albumin, Calcium total, Magnesium total 
(Mg), Inorganic Phosphorus, Alkaline Phosphatase, ALT/GPT, AST/GOT, Total 
Bilirubin, Direct Bilirubin, LDH, CRP, Total Protein, Uric Acid, ferritin, triglyceride 
level
•
 Immunoglobulins 
•
CBC with differential and platelet count
•
Urinalysis

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2.3.2.5
Disease Evaluation
•
Based on participant’s primary disease, not all listed evaluations need to be completed, 
per PI discretion. Appropriate imaging methods of any sites relevant to the subject’s 
disease (e.g., CT Scan, PET/CT, or MRI). 
•
Bone marrow aspirate including flow cytometry (bone marrow biopsy as feasible)
•
Spinal fluid for cell count, cytospin. Only in participants with a history of CNS disease at 
PI discretion. CSF for flow cytometry may be done per PI discretion, as feasible.
•
Other tissue biopsy may be performed as clinically indicated for immunohistochemistry 
and/or flow cytometry of a fine needle aspirate
•
Peripheral blood for flow cytometry 
•
Pulmonary Function Evaluation
•
Pulse oximetry
•
Pulmonary function testing (spirometry and DLCO) will only be required in participants 
with respiratory symptoms (e.g. dyspnea at rest or known requirement for supplemental 
oxygen).
•
For children who meet the above criteria but are unable to cooperate for PFTs, the 
criterion is:  No evidence of dyspnea at rest, no exercise intolerance and no requirement 
for supplemental oxygen therapy. 
2.3.2.6
Cardiac Function
•
ECG
•
Assessment of cardiac function (ejection fraction/shortening fraction) echocardiogram or 
cardiac MRI.
2.4
PARTICIPANT REGISTRATION AND STATUS UPDATE PROCEDURES
Registration and status updates (e.g., when a participant is taken off protocol therapy and when a 
participant is taken off-study) will take place per CCR SOP ADCR-2, CCR Participant 
Registration & Status Updates found at: 
https://ccrod.cancer.gov/confluence/pages/viewpage.action?pageId=73203825.
2.4.1
Screen Failures
Screen failures are defined as participants who consent to participate in the clinical trial but are 
not subsequently assigned to the study intervention or entered in the study. A minimal set of 
screen failure information is required to ensure transparent reporting of screen failure 
participants, to meet the Consolidated Standards of Reporting Trials (CONSORT) publishing 
requirements and to respond to queries from regulatory authorities. Minimal information 
includes demography, screen failure details, eligibility criteria, and any serious adverse event 
(SAE).
Individuals who do not meet the criteria for participation in this trial (screen failure) because of 
an eligibility criterion may be rescreened.

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Abbreviated Title: CD19/CD22 T-cell in Peds
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2.4.2
Treatment Assignment Procedures
2.4.2.1
Cohorts
Number
Name
Description
1
Dose Escalation
Up to 17 subjects previous to amendment, version date 
01/11/2020 CLOSED
1a
Dose Escalation: CAR 
naïve or previously 
CAR treated with 
interim transplant  
Up to 13 CAR naïve or previously CAR treated with 
interim transplant or highest dose administered is 
determined (as of amendment, version date 01/11/2020) 
CLOSED
1b
Dose Escalation: 
previously CAR treated 
but not transplanted
Up to 13 previously CAR treated but not transplanted or 
highest dose administered is determined (as of 
amendment, version date 01/11/2020) CLOSED
2a
Dose Expansion: CAR-
T naïve or previously 
CAR treated with an 
interim transplant
Up to 30 CAR naïve previously CAR treated with an 
interim transplant subjects treated at MTD.  15 enrolled 
initially (counting those treated at MTD in cohort 1) 
then expanded to 30 if sufficient response
2b
Dose Expansion: prior 
CAR-T therapy without 
an interval transplant 
Up to 30 subjects with prior CAR-T therapy without an 
interval transplant treated at MTD. 15 enrolled initially 
(counting those treated at MTD in cohort 1) then 
expanded to 30 if sufficient response
2c
Dose Expansion: 
Isolated CNS disease
Up to 12 subjects with isolated CNS disease
2.4.2.2
Arms
Number
Name
Description
1
Dose Escalation
CD19/CD22-CAR-transduced T cells at escalating 
doses
2
Dose Expansion
CD19/CD22-CAR-transduced T cells at MTD or 
highest dose administered
2.4.2.3
Arm Assignment
Subjects in Cohort 1, 1a and 1b will be directly assigned to Arm 1.
Subjects in Cohorts 2a, 2b, 2c will be directly assigned to Arm 2.

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Abbreviated Title: CD19/CD22 T-cell in Peds
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3
STUDY IMPLEMENTATION
3.1
STUDY DESIGN
This is a single-site phase I study in pediatric and young adult participants with CD19+CD22+ 
expressing B cell hematologic malignancies who have relapsed or refractory disease after at least 
one standard chemotherapy and one salvage regimen. All participants enrolled on this trial have 
been deemed incurable by standard therapies. Autologous PBMC will be obtained by 
leukapheresis and transduced with CD19/CD22-CAR lentiviral vector. Cryopreserved PBMC 
stored from participation in other institutional cell therapy or cell collection studies may be used 
to generate the cellular product on this study as long as they meet the criteria described in the 
IND.  
The first participant treated in each cohort will be evaluated for 21 days prior to the treatment of 
the second participant in a cohort to provide an initial safety evaluation prior to administration in 
subsequent participants at that dose level. We believe this staggering regimen is adequate to 
demonstrate safety in children particularly given the similarity of this CAR construct to those 
that have been used safely in pediatric participants receiving the CD22 CAR T cells and CD19 
CAR T cells. The preparative regimen cyclophosphamide and fludarabine has been used 
successfully in many CAR clinical trials with acceptable toxicity profile.
Participants will receive a lymphodepleting preparative regimen of fludarabine and 
cyclophosphamide followed by infusion of CD19/CD22-CAR T cells. Participants will be 
evaluated sequentially after treatment for toxicity, antitumor effects and for persistence of CAR 
in blood samples and functionality of transduced T cells. Additional blood and bone marrow 
samples will be collected to complete correlative study analysis.
Initially participants will receive 3 x 105 transduced T cells/kg (± 20%) as outlined in section 3.7.  
If no adults have received this dose prior to initiating enrollment on this study, at least 1 
participant ≥ 18 years of age or older will undergo investigational cellular therapy without DLT 
(observed for 28 days after infusion) prior to treating pediatric participant, as per section 3.7.  If 
2/6 participants experience DLT at dose level 1, dose -1 will be explored (1 x 105 transduced T 
cells/kg (± 20%)) as described in section 3.7.  The MTD, or highest cell dose studied if MTD is 
not reached, will be expanded in two groups (children and young adults who have previously 
received CAR T cells versus those that are CAR T cell-naïve) for a total of 12 evaluable 
participants in each group to further explore the safety, feasibility and clinical response activity.
With a limited dose escalation and/or de-escalation if needed, utilizing a 3+3 Phase 1 design, 
utilizing a biologically active and well tolerated dose for both CD19 and CD22-CAR trials. If 
tolerated and safety has been assessed, we will have a very limited dose escalation to 3 x 106/kg. 
Based on the data from the first 11 participants treated on study, at the three current dose levels, 
we propose adding an additional dose level, DL 4: 1 x 107 transduced T cells/kg, to explore due 
to limited expansion and limited persistence of CAR T cells with favorable toxicity profile. 
Additionally, participants that have received previous CAR therapy are eligible to enroll on trial, 
however, based on our experience to date on this trial and others, participants may have limited 
responses to subsequent infusions with CAR-T therapy, especially when the same antigen is 
targeted.

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Abbreviated Title: CD19/CD22 T-cell in Peds
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As this is a dual, bispecific construct targeting CD19/CD22, our plan is to enroll participants in 
two groups: CAR naïve and CAR pretreated as toxicity profile and response rates may be 
different between these two groups. Additionally, based on our experiences to date, we have 
utilized intensified lymphodepletion as a strategy to reduce the likelihood of immune mediated 
rejection, and potentially improve response rate in participants who have had prior CAR T-cell 
exposure, and this strategy will be utilized for the CAR pretreated cohort. This intensified 
lymphodepletion has been well tolerated and represent a moderate increase above our standard 
dosing. Starting at dose level 4, participants will be enrolled in separate cohorts based on prior 
treatment. 
3.2
APHERESIS FOR CELL ACQUISITION 
Participants will undergo apheresis according to institutional standards, as estimated by recipient 
weight and target cell harvest dose in the institution apheresis facility. If PBMCs have been 
cryopreserved in DTM-CC for a different cell therapy or cell collection study and meet the 
requirements for this study, they may be used to generate CD19/CD22-CAR T cells on this 
study.
A target cell number extrapolated based upon the expected expansion and planned cell dose of 
transduced T cells/kg will be collected. Citrate anticoagulant may be used in subjects according 
to institutional SOPs. For subjects, less than 18 kg, low-dose heparin may be added. Prophylactic 
intravenous CaCl2 and MgSO4 infusions may be administered by the apheresis clinical team per 
institutional standard operating procedures. Institutional guidelines will be followed for venous 
access and apheresis procedures.  
3.3
CELL PROCESSING 
Cellular Product: Autologous T cells cultured with interleukin-2; transduced with lentiviral 
vector (CD19/CD22.BB.z) expressing CD19/22 Chimeric Antigen Receptor (Anti-CD19/CD22 
CAR); following Fludarabine and Cyclophosphamide 
Cell therapy production will be conducted according to the DTM-CCE SOPs and must meet the 
requirements for a GMP facility.  Fresh or cryopreserved peripheral blood mononuclear cells 
(PBMC) (depending on the timing of apheresis relative to cell culture, participant condition and 
scheduling availability) will be enriched for T cells using a CD4/CD8 immunomagnetic bead 
enrichment.  They will then be activated by co-culture with immunomagnetic particles 
expressing anti-CD3 and anti-CD28 mAb. One day following activation, replication incompetent 
lentiviral vector particles containing the CD19/CD22.BB.z construct will be added to the culture 
for transduction.  Cells will be incubated for approximately 9 days with IL-2 then harvested and 
administered fresh or frozen for subsequent infusion.  Cells will be required to meet standard 
release criteria including transduction efficiency ≥10%, T cell content ≥70%, sterility and 
minimum levels of LPS as well as no evidence for replication competent lentivirus.  All 
procedures will take place using good manufacturing process guidelines.
The release criteria will be based upon analyses for each dose of CD19/CD22-CAR T cells and 
will include:
Test
Method
Criteria
Cell viability1
Trypan blue exclusion 
≥70% 

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Abbreviated Title: CD19/CD22 T-cell in Peds
Version Date: November 19, 2024
Test
Method
Criteria
Cell number1
cell counter
within 20% of planned 
dose level 
% CAR+ cells2
Anti-CD19 CAR idiotype, 
CD22 Fc 
≥10% 
Endotoxin1 
Gel Clot 
≤ 5 EU/mL 
Mycoplasma2 
Mycoplasma test
Negative 
VSV-G2
q-PCR
Negative
Sterility testing3 
gram stain, culture 
Negative 
1Performed on sample from final product immediately prior to infusion, results available at the time of 
infusion.
2Performed on sample between Day –4 and Day –1. Results are available at time of infusion.
3Gram stain is performed on final product prior to infusion and is available at the time of infusion, cultures 
will be sent from Day –2 product and results will be in process at the time of infusion, therefore they may 
not be definitive.
Any prepared cells not required for infusion or for research or regulatory purposes will be 
cryopreserved by standard techniques and will be made available should the subject be eligible 
for a reinfusion as outlined in section 3.11.
3.4
IMPACT OF DISEASE PROGRESSION OR DELAY IN INITIATION OF PROTOCOL SPECIFIED 
THERAPY AFTER ENROLLMENT 
Participants must have evaluable disease at the time of protocol enrollment. PBMC will be 
collected and every effort will be made to initiate cell culture within 60 days so minimal time 
transpires for a participant’s disease to progress significantly. However, for most participants 
with active leukemia, 60 days is still an unacceptable period to wait without any additional 
therapy. Furthermore, there may be delays in cell manufacturing that are beyond our control that 
need to be accounted for. With the goal of optimizing a subject’s clinical condition, should a 
subject develop evidence of disease progression after enrollment, or require intermittent doses of 
low-dose chemotherapy to maintain disease stabilization or prevent disease progression, but 
before initiation of protocol specified lymphodepleting chemotherapy, the subject may be treated 
with disease-directed standard of care (SOC) (i.e., non-investigational) chemotherapy as 
clinically indicated and initiation of protocol-specified lymphodepleting chemotherapy will be 
delayed. Participants may receive interim SOC therapy either with their local physician or at 
NIH.  If the participant receives therapy with his/her local physician, neither the therapy nor the 
AEs from this therapy will be recorded or reported on this protocol (except as part of prior 
history at baseline) as this information is external to the study.  If the participant chooses to 
receive interim SOC therapy at NIH, the participant will be enrolled to protocol 04-C-0165 
Standard of Care and Interventions protocol and the therapy and associated AEs will be reported 
on protocol 04-C-0165. 

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After completion of interim SOC therapy and in order to initiate the protocol-specified 
lymphodepleting therapy, there must be 7 days from the last dose of standard chemotherapy 
(with the exclusion of steroids and hydroxyurea where there is no washout.)
For all participants that have received any form of SOC interim therapy, the following labs will 
be repeated prior to starting lymphodepleting chemo: CBC, chemistries including sodium, 
potassium, chloride, total CO2, creatinine, glucose, urea nitrogen, albumin, alkaline phosphatase, 
ALT/SGPT, AST/SGOT, total bilirubin, Lactate Dehydrogenase (LDH),uric acid, ferritin, and 
triglycerides. These labs can be collected as baseline labs prior to starting lymphodepleting 
chemotherapy.
Also, per PI discretion, the participant may have repeat disease evaluations performed (method 
determined by participants’ type and location of disease) in order to proceed with 
lymphodepleting therapy and planned CAR infusion. For participants who only receive 
maintenance like-ALL therapy, as defined in protocol section 2.1.2.5, or steroids for the purpose 
of disease stabilization or to prevent disease progression, restaging evaluation will only be 
performed if clinically indicated per PI discretion. Baseline data will be collected.  Data 
regarding the interim SOC therapy will be captured in prior therapy CRFs, but no AEs will be 
collected or reported for this protocol until the participant initiates study therapy.
3.5
IMPACT OF INTERCURRENT ILLNESS AFTER ENROLLMENT
Should a subject develop a serious or life-threatening condition or infection (not including 
progressive disease) after enrollment and either before or after lymphodepleting therapy, the 
subject will be treated for their condition as clinically indicated and administration of anti-
CD19/22-CAR T cells will be delayed. Cells will be maintained in culture for up to an additional 
72 hours while attempts are made to correct the condition. Cells may be infused within this 
period only if the PI determines that administration of the cells does not pose any additional risk 
to the subject. If the participant is able to receive fresh, non-cryopreserved cells within 72 hours 
of the planned original dose on Day 0, administration should follow the procedure as outlined in 
section 3.10 and the participant will remain evaluable for toxicity and efficacy. If more than 72 
hours from planned cell harvest elapses, the cells will be cryopreserved and, if clinically 
indicated, the subject may receive them up to 7 days from the planned infusion date and be 
considered evaluable.  Alternatively, the subject may have the option of receiving the cells at a 
later point once the condition has resolved, but these participants will not be evaluable for 
toxicity and efficacy and will be replaced in the accrual numbers.
3.6
DOSE LIMITING TOXICITY (DLT) / TREATMENT LIMITING TOXICTY (TLT)
Adverse events that are considered disease-related (not suspected of relationship to CD19/CD22-
CAR T cells) will not be considered dose-limiting toxicities. Only those AEs suspected to be 
related to pre-infusion chemotherapy and/or CD19/CD22-CAR T cells (any component of the 
treatment regimen) will be used in the definition of DLT/TLT. As the dose escalation portion of 
the study has completed, Treatment-limiting toxicities will now be captured during the dose 
expansion phase. Toxicities occurring after initiation of the chemotherapy preparative regimen 
but prior to CD19/CD22-CAR T cell infusion, will primarily be attributable to the chemotherapy 
administration or disease, if not extraneous causes. After cell infusion, toxicities will be 
evaluated for temporal and causal relationship to chemotherapy versus cell infusion. Some 
symptoms may overlap, and attribution will not be clearly definable, in which case, toxicities 

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will be attributed as possibly related to both preparative regimen and cell infusion. Toxicities 
will be attributed to the T cells if: 1) they were NOT present before T cell infusion; OR 2) they 
increase in Grade in temporal association with the T cell infusion; AND 3) they are not clearly 
explained by other factors. Participants who are fully assessable are those that have completed 
the non-myeloablative preparative regimen and received the CD19/CD22-CAR T cell infusion. 
DLT/TLT will only be attributed to the preparative regimen if it prevents infusion of 
CD19/CD22-CAR T cells.
The definition of DLT/TLT in these studies uses NCI’s Common Terminology Criteria for 
Adverse Events (CTCAE v5).
3.6.1
Definition of DLT/TLT 
Adverse events that are at least possibly related to the CD19/CD22-CAR T cells with onset 
within the first 28 days following cell infusion will be considered DLT/TLTs according to the 
following criteria or exceptions: 
3.6.1.1
Hematological Toxicity: 
Subjects with normal, Grade 1 or Grade 2 Hematologic Parameters at baseline (independent of 
transfusion) and cytopenias NOT due to Bone Marrow Involvement by Disease 
•
Any Grade 4 hematological toxicity (i.e., neutropenia or thrombocytopenia with the 
exception of lymphopenia) lasting greater than 30 days will be considered a DLT/TLT. 
Lymphocyte count and subsets will not be considered in the definition of DLT/TLT. 
Subjects with abnormal blood counts (Grades 1 through 4) at baseline due to bone marrow 
involvement by disease 
•
These subjects will be considered non-evaluable for hematologic DLT but evaluable for 
all other aspects of the study. 
3.6.1.2
Non-Hematological Toxicity:
•
Any grade 4 adverse event at least possibly related to research or IND, with exclusion 
of transient, laboratory abnormalities without clinical consequence, will be 
considered DLT/TLT. 
•
CRS Grade 4 in severity, or Grade 3 in severity for more than 7 days
•
Infusions reactions ≥ Grade 2 lasting more than 24 hours
•
Grade 4 Cerebral Edema
•
> Grade 3 Neurotoxicity
•
> Grade 3 Disseminated Intravascular Coagulation
The MTD is a dose level immediately below the level at which the enrollment is stopped due to 
DLTs, as explained specifically below:
•
If more than one subject in the first three subjects included in a dose level experience 
DLT as defined above, MTD will have been exceeded.
•
If DLT develops in one of the 3 subjects included in a cohort, the cohort will be then 
expanded up to six:
•
If 2 or more of these 6 included participants develop DLT, the MTD will have been 
exceeded.

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If no additional subject develops a DLT, the MTD will not have been exceeded and the cohort 
will be evaluated for response.  If < 3 responses are present in this dose cohort the next dose 
level can be administered after the four-week safety assessment period of the last participant at 
this dose level.
If MTD is exceeded at any dose level, three subjects will be added to the immediate lower dose 
level, unless it has been previously expanded to six. If less than 2 of 6 subjects develop DLT at 
that level, it will be defined as the MTD.
3.7
DOSE ESCALATION
Cell dose will be body weight-based up to 100kg. All participants > 100kg, with a BMI <35, will 
be cell dosed at 100kg. All participants with BMI greater than 35 will have doses calculated 
using practical body weight (PBW) (see Appendix E for calculation), with dosing also capped at 
100kg.
Initially 3 to 6 participants will receive 3 x 105 transduced T cells/kg (± 20%).  If this dose has 
been deemed to be safe in adults (1 adult participant has received this dose without DLT) 
pediatric participants may be enrolled and treated.  If no adults have received this dose (or 
subsequent dose levels) prior to initiating enrollment at the specified dose level on this study, at 
least 1 participant ≥ 18 years of age or older will undergo investigational cellular therapy without 
DLT (observed for 28 days after infusion) prior to treating a pediatric participant.  A four (4) 
week (28 days) safety assessment period will follow regimen completion (defined as infusion of 
CD19/CD22-CAR T cells) of the first participant in the first cohort (and subsequent cohorts if 
needed). Subsequent participants in that dose cohort and subsequent cohorts may be treated after 
a one week (7 day) safety assessment period.  Four weeks (28 days) must elapse after completion 
of cell infusion in the final participant in each cohort to allow for safety assessment of the dose 
cohort and response determination before treating participants on the next dose cohort level, if 
escalation is needed.  
In addition, at the discretion of the principal investigator, an additional 1-2 participants may be 
enrolled at a single dose level to obtain information on efficacy and safety provided that no more 
than 1 participant at that dose level has experienced a DLT.
If < 3 out of 6 participants demonstrate an objective response (CR or PR) at Dose Level 1, AND 
< 2 out of 6 participants experiencing DLT, the dose will be escalated to Dose Level 2: 1 x 106 
transduced T cells/kg (± 20%) in subsequent participants.  Safety, including enrollment 
staggering and efficacy will again be assessed as described above for Dose Level 1.  If needed, 
the dose may be escalated to Dose Level 3, then 4 should previous dose levels prove to be safe 
but not efficacious.
Dose Escalation Schedule
Dose Level
Dose of CD19/anti-CD22-CAR T cells
Level -1
1 x 105 transduced T cells/kg (± 20%)
Level 1
3 x 105 transduced T cells/kg (± 20%)

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Dose Escalation Schedule
Dose Level
Dose of CD19/anti-CD22-CAR T cells
Level 2
1 x 106 transduced T cells/kg (± 20%)
Level 3
3 x 106 transduced T cells/kg (± 20%)
Level 4
1 x 107 transduced T cells/kg (± 20%)
If cell growth limitations preclude administration of the number of cells targeted for the assigned 
cohort level, a second or subsequent culture may be initiated and the participant can receive 
interim standard therapy as per protocol section 3.4 while awaiting additional cells to see if they 
can reach the specified dose level. Ultimately, the participant will receive as many cells as 
possible and the participant will be enrolled in the appropriate cohort for the number of cells 
infused, allowing for an additional two participants to be enrolled per cohort due to cell growth 
limitations. Based on prior experience we do not anticipate many product failures. If a DLT 
occurs in an additional participant (beyond the first 3 enrolled) entered at a lower dose due to cell 
growth limitations, accrual will continue at the previously planned dose level for subsequent 
participants. If a minimum of 3x105/kg CD19/CD22-CAR-transduced T cells cannot be obtained 
for infusion (or 1 x 105/kg if dose level -1 is enrolling), the participant will still receive the cell 
infusion, as the effective dose of cells is not well defined, and the participant will be evaluable 
for feasibility but not analyzed for MTD, although toxicities will be assessed and reported 
separately. If the third dose level is completed without DLT and without clinical response, 
consideration may be given to adding additional dose cohorts in a protocol amendment. After 
treatment of the first 11 participants, in the first 3 dose levels, without any DLT, and limited 
clinical response, we propose adding an additional dose level, (DL 4: 1 x 107 transduced T 
cells/kg).
If cell growth limitations preclude administration of the number of cells targeted for the assigned 
dose level in 3 participants (out of 6) in a dose level, that dose will be considered not feasible as 
there will be inadequate number of participants in that dose level to evaluate safety.  Enrollment 
to that dose, and any higher doses will cease.  This will be considered the ‘highest cell dose’ 
studied and will be the dose level that will be studied further in the expansion cohort.
3.8
DOSE EXPANSION COHORT
To gain further experience with the safety, feasibility and clinical activity of the CD19/CD22 
CAR T cells in this participant population and to determine if there are differences in the 
feasibility related to manufacturing or administering CD19/CD22-CAR T cells in children and 
young adults who have previously received CAR T cells versus those that are CAR T cell-naive, 
the MTD (or highest cell dose studied) will be expanded in two groups of subjects to a total of 
15-30 participants in each expansion cohort (i.e., will include those subjects treated at MTD 
during the dose escalation phase). If 50% or more of the participants experience a clinical 
response (best overall response), this therapeutic regimen will be of sufficient efficacy to warrant 
additional study.

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3.9
LYMPHODEPLETING CHEMOTHERAPY REGIMEN
3.9.1
Criteria for Initiating Lymphodepleting Regimen
The criteria for initiating the conditioning regimen is as follows:
Participants must have 
•
no evidence of clinically significant infection, 
•
no clinically significant cardiac dysfunction, 
•
serum creatinine must be <2 x ULN, 
•
no acute neurological toxicity >grade 1 (with the exception of peripheral sensory 
neuropathy).
Should an event exceed these criteria immediately prior to conditioning chemotherapy, 
conditioning chemotherapy must be delayed until the event resolves to ≤ grade 1 or baseline.
3.9.2
Drug Administration
3.9.2.1
CAR naïve or CAR pre-treated with interval transplant participants
Participants will receive the lymphodepleting regimen as follows: (This may be given as an 
inpatient or outpatient as necessary). 
Drug
Dose
Supportive Care
Days
Fludarabine
25 mg/m2 per day% IV 
infusion in 50-100 mL 
of 0.9% sodium 
chloride over a 
minimum of 30 
minutes, daily for 3 
days.
-4, -3, -2
Cyclophosphamide
900 mg/m2 per day IV 
infusion over a 
minimum of 60 
minutes, once on Day -
2 after fludarabine
Pre-cyclophosphamide 
hydration:
IV pre-hydration at a rate of at 
least 100 ml/m2/hr of Normal 
Saline (NS) for a minimum of 
2 hours prior to 
cyclophosphamide or 
alternatively, rapid pre-
hydration can be given at 750 
mL/m2 of NS over 1 hour.
Post-cyclophosphamide 
hydration:
IV or oral hydration until the 
completion of mesna at a rate 
of at least 100 mL/m2/hour. 
-2

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Drug
Dose
Supportive Care
Days
Mesna used as described 
below 
% To conserve vials in times of drug shortages, individual  (i.e., daily) fludarabine doses may be 
rounded up or down by ≤15% with approval of the PI to reach the targeted cumulative dose of 75 
mg/m2 (+/- 10%) over 3 days.
3.9.2.2
CAR pre-treated without an interval transplant or participants receiving a reinfusion:
Participants will receive intensified lymphodepletion  as follows: 
(This may be given as an inpatient or outpatient as necessary): 
Drug
Dose
Supportive Care
Days
Fludarabine
30 mg/m2 per day$ IV 
infusion in at least 
50mL of 0.9% sodium 
chloride over a 
minimum of 30 
minutes, daily for 4 
days.
-5, -4, -3, -2
Cyclophosphamide
600 mg/m2 per day IV 
infusion over a 
minimum 60 minutes, 
daily for 2 days, dosed 
after fludarabine.
Pre-cyclophosphamide 
hydration:
IV pre-hydration at a rate of 
at least 100 ml/m2/hr of NS 
for a minimum of 2 hours 
prior to cyclophosphamide 
or alternatively, rapid pre-
hydration can be given at 
750 mL/m2 of NS over 1 
hour. 
Post-cyclophosphamide 
hydration:
IV or oral hydration until the 
completion of mesna at a 
rate of at least 100 
mL/m2/hour.Mesna as 
described below. 
-3 and -2
$ To conserve vials in times of drug shortages, individual  (i.e., daily) fludarabine doses may be 
rounded up or down by ≤15% with approval of the PI to reach the targeted cumulative dose of 
120 mg/m2 (+/- 10%) over 4 days.

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3.9.2.3
Alternative Lymphodepletion Regimen (when Fludarabine is unavailable)
Alternative Lymphodepletion Strategy
Standard LD
Pentostatin 2mg/m2 Day -4 %
Cyclophosphamide 900 mg/m2 Day -2
Increased LD
Pentostatin 1.5mg/m2 Day -5, -4% (cumulative 3mg/m2)
Cyclophosphamide 600 mg/m2 Day -3, -2 (cumulative 1200mg/m2)
% Administer IV over 20 to 30 minutes or as a bolus infusion. Hydrate with 500 to 1,000 mL of 5% 
Dextrose in 0.45% NS or equivalent before infusion, and  500 mL of 5% Dextrose or equivalent after 
infusion.
3.9.3
Supportive Care Measures
3.9.3.1
Mesna
Mesna will be administered per institutional/national standards on days when cyclophosphamide 
is administered.
3.9.3.1.1 Inpatient Mesna
Mesna will be administered at a dose that equals 60% of the daily cyclophosphamide dose by 
continuous IV infusion on days when cyclophosphamide is given. Mesna will be prepared in 5% 
dextrose (or other composition appropriate for the clinical situation) and will be infused over 9 
hours starting concurrently with the cyclophosphamide.
3.9.3.1.2 Outpatient Mesna
First dose: All participants will receive the first dose of mesna IV given concurrently with the 
cyclophosphamide, at a dose that is 20% of the cyclophosphamide dose. IV Mesna will be 
prepared in 5% dextrose (or other composition appropriate for the clinical situation). 
Subsequent doses: The second and third doses of mesna can be given either IV or orally (note:  
the oral mesna dose is twice the IV mesna dose).
Subsequent IV mesna :  Each dose will be 20% of the cyclophosphamide dose, given at 4 and 8 
hours after the start of cyclophosphamide (for a total daily mesna dose equal to 60% of the daily 
cyclophosphamide dose).
Subsequent oral mesna:  Participants able to tolerate oral mesna may receive the last two bolus 
doses orally. Each oral mesna dose will be 40% of the cyclophosphamide dose, given at hours 2 

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and 6 after the start of cyclophosphamide (for a total daily mesna dose equal to 100% of the daily 
cyclophosphamide dose.) Oral mesna solution is 100 mg/mL and should be diluted prior to 
administration to improve palatability. Participants will receive instructions from pharmacy 
describing how to dilute mesna for consumption in the outpatient setting (e.g. dilute each dose in 
1 ounce of water, carbonated beverages, fruit juice, milk, etc.). Participants who vomit within 2 
hours after taking oral mesna should repeat the dose or receive IV mesna instead. 
3.9.3.2
Anti-emetics
Routine anti-emetic prophylaxis and treatment should be employed. Corticosteroids may not be 
used (except for physiologic replacement as outlined in section  2.1.2.5, or in IT chemotherapy 
as outlined in section 4.1). 
3.10 CD19/CD22-CAR T CELL INFUSION – DAY 0 
3.10.1 Cell Infusion Criteria
Subjects must meet the following criteria in order for cells to be infused (based on labs obtained 
within 1 day of cell infusion):
•
CD19/CD22-CAR T cells must have met release criteria (section 3.3)
•
Subject has no evidence of hemodynamic instability
•
Subject has not developed a new requirement for supplemental oxygen therapy
•
Subject has not developed symptoms concerning for new, systemic infection or condition 
that in the opinion of the PI may pose an unacceptable risk to the subject
•
Liver transaminase (ALT and AST) < 10 x ULN based on age- and laboratory specific 
normal ranges
•
There is no evidence of clinically significant cardiac dysfunction, uncontrolled, 
significant tumor lysis syndrome, serum creatinine >2 x ULN, and no acute neurological 
toxicity > grade 1 (with the exception of peripheral sensory neuropathy).
Should an event not meet these criteria immediately prior to receiving CD19/CD22-CAR T cell, 
the cell infusion must be delayed until the event resolves.  If the CD19/CD22-CAR T cell 
infusion is delayed >2 weeks, conditioning chemotherapy MAY be repeated, unless investigator 
deems this unnecessary. In addition to the above criteria, special considerations should be made 
prior to cell infusion if the subjects’ temperature is ≥ 38.0 C within 48 hours prior to cell 
infusion. 
3.10.2 Inpatient and Outpatient Care Post-Cell Infusion: 
Participants may be admitted for cell infusion to NIH in accordance with CC and nursing 
policies. Participants will be monitored a minimum of twice weekly until Day 14 as inpatients or 
outpatients but must be admitted with the first fever or with clinical manifestations of CRS. 
Participants should remain outpatient in close proximity to the NIH for at least twice weekly 
evaluations until completion of Day 28 (+/- 4 days) restaging evaluations unless participant does 
not show signs of cytokine release syndrome or CAR expansion. 

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3.10.3 Pre-medications 
Participants will receive the following medications prior to cell infusion (it is recommended that 
these pre-medications be given 15-90 minutes prior to the cell infusion, but they may be 
administered up to 4 hours prior to the infusion): 
Diphenhydramine 0.5 - 1 mg/kg/dose (maximum 50 mg/dose) PO or IV over 10-15 minutes; 
Acetaminophen 15 mg/kg/dose (maximum 650 mg/dose) PO. Premedications may be omitted 
based on clinical conditions at the discretion of the PI or AI.  
3.10.4 Cell Administration
Cells are delivered to the participant care unit by a staff member from the institutions’ Cell 
Processing Service. Prior to infusion, the cell product identity label is double-checked by two 
authorized staff (MD or RN), an identification of the product and documentation of 
administration are entered in the participant’s chart, as is done for blood banking protocols. 
The cells are to be infused intravenously (IV) over 5-20 minutes via syringe(s).
For cryopreserved cells, the cellular product will be thawed and administered IV immediately at 
a rate of approximately 10-15 ml/min or as tolerated based on volume status and/or DMSO 
toxicity. Do not exceed 20 ml of product per kg body weight (if 10% DMSO) or 40 ml of 
product per kg body weight (if 5% DMSO) so that per 24-hour period total DMSO administered 
is less than 1 mL/kg/day. 
3.10.5 Required Monitoring During Cell Infusion
Monitoring will include vital signs (temperature, blood pressure, heart rate, respiratory rate) prior 
to infusion, at the end of the infusion, every 15 minutes (± 5 min) after the end of the infusion X 
2, every 30 minutes (±10 min) after the end of the infusion X 2. Vital signs may be evaluated 
more frequently if clinically indicated.
3.10.5.1 Supplemental oxygen will be available at the bedside 
If an allergic or other acute reaction occurs, studies appropriate for investigation of a transfusion 
reaction will be performed (urinalysis, CBC, Coombs test). Acute reactions will be treated 
according to institutional standards of care.
3.11 OPTION FOR ADDITIONAL DOSE(S) OF CD19/CD22-CAR T CELLS
On the day cells are infused, 90% of any remaining cells that have been produced above and 
beyond the number of cells needed for a subject’s dose level will be cryopreserved using 
standard techniques. 10% of the remaining cells will be used for research. Subjects will have the 
option for additional infusions of CD19/CD22-CAR T cells (including preparative chemotherapy 
regimen, toxicity assessment and research blood sampling) if the following criteria are met:
3.11.1 Eligibility Criteria for Subsequent Cell Infusions 
3.11.1.1 Inclusion Criteria
3.11.1.1.1 Response to previous infusion. Subjects who had a PR, or SD with clinical benefit 
may elect to receive another infusion of cells. Clinical benefit is indicated by an 
improvement in the subject’s health status (e.g., decreased transfusion requirement, 
improved cytopenias, decrease in number of blasts not sufficient to reach a PR, 

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improved performance status, or quality of life etc.) Subjects that initially had a CR 
may receive a reinfusion  if any of the following criteria is met:
•
Evaluable disease recurs;
•
If participant has loss of B cell aplasia defined by an absolute CD19+ > 50/mcL 
and rising in the peripheral blood (2 timepoints needed), and/or 1% CD19+ 
hematogones in the bone marrow;
•
If a participant has loss of CAR T cell persistence (<5% circulating CAR T cell in 
peripheral blood by flow cytometry) < 6 months post-initial infusion. 
3.11.1.1.2 At least 30 days have passed since the previous cell infusion.
3.11.1.1.3 At least six weeks from most recent DLI infusion.
3.11.1.1.4 Circulating levels of CD19/CD22-CAR T cells must be <5% in peripheral blood by 
flow cytometry.
3.11.1.1.5 Participants must have been previously infused with CD19/CD22 CAR T cells on 
study and have at least 1 additional dose cryopreserved. (The cell dose based on CAR 
transduced cells) for the reinfusion will be the same dose as the initial infusion dose)
3.11.1.1.6 Any toxicity (regardless of causality) after the previous CD19/CD22-CAR T cell 
infusion must resolve such that subjects meet the following eligibility criterian (based 
on labs obtained within 1 day of cell infusion): 
3.11.1.1.7 CD19/CD22-CAR T cells must have met release criteria (section 3.3)
3.11.1.1.8 Subject has no evidence of hemodynamic instability
3.11.1.1.9 Subject has not developed a new requirement for supplemental oxygen therapy
3.11.1.1.10
Subject has not developed symptoms concerning for new, systemic infection or 
condition that in the opinion of the PI may pose an unacceptable risk to the subject
3.11.1.1.11
Liver transaminase (ALT and AST) < 10 x ULN based on age- and laboratory 
specific normal ranges
3.11.1.1.12
There is no evidence of clinically significant cardiac dysfunction, uncontrolled, 
significant tumor lysis syndrome, serum creatinine >2 x ULN, and no acute 
neurological toxicity > grade 1 (with the exception of peripheral sensory neuropathy).
3.11.2 Exclusion Criterion for Subsequent Cell Infusions
Participants who incurred TLT after receiving the first cell infusion will not be eligible to receive 
additional cell infusions unless IRB and FDA approval is granted on a case by case basis.
3.11.3 Additional Antineoplastic and Lymphodepleting Chemotherapy
Participants may receive additional antineoplastic and lymphodepleting chemotherapy prior to 
the reinfusion of CD19/CD22-CAR T cells. See section 3.9.2 for lymphodepletion dosing.

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3.11.3.1 Rationale for Intensified Lymphodepletion
Given the historically limited response with second or subsequent infusions, which is believed to 
be due to an anti-CAR immune mediated rejection of the infused CAR-T cells that develops after 
the first infusion, in subjects who meet the above eligibility criteria for subsequent infusion and 
who have evidence for either a) limited CAR-T cell expansion with the first infusion; b) rapid 
loss of CAR-T cells suggesting limited persistence; c) loss of B cell aplasia as defined above; d) 
incomplete response where a reinfusion to improve upon the initial response could be 
considered; incorporation of an intensified lymphodepleting regimen consisting of 4 days of 
fludarabine 30 mg/m2/dose (days -5, -4, -3, -2) and 2 days of cyclophosphamide 600 
mg/m2/dose (days -3, -2) may be utilized along with the same initial dose of CAR-T cells 
infused. All subjects who receive subsequent infusion must meet LD initiation criteria as per 
section 3.11.1. 
Based on institutional experience with a similar regimen on the POB Anti-CD22CAR protocol 
15-C-0029, this regimen is well tolerated in the setting of CAR-T cell therapy. The goal of the 
intensified regimen would be used to reduce the likelihood of immune rejection of the infused 
CAR-T cells and improve the response. As per section 3.11.1.1.5, all toxicities will be monitored 
and if two or more participants develop unexpected grade 4 toxicity from the chemotherapy 
regimen, then utilization of this regimen will be paused pending further discussion and review.
On the day of infusion, the cellular product will be thawed and administered IV immediately (as 
per institutional guidelines) at a rate of approximately 10-15 ml/min or as tolerated based on 
volume status and/or DMSO toxicity. Do not exceed 20 ml of product per kg body weight (if 
10% DMSO) or 40 ml of product per kg body weight (if 5% DMSO) so that per 24-hour period 
total DMSO administered is less than 1 mL/kg/day.
3.11.3.2 Post Infusion Monitoring
Any subject who receives subsequent infusions of CD19/CD22-CAR T cells will NOT be 
evaluable for TLT purposes of this study as they will be beyond the 28-day observation period 
for TLTs after their first cell infusion.  However post-infusion monitoring will be the same as for 
the 1st infusion and all toxicities, including secondary reactions, will be recorded and reported.  
If two or more participants develop Grade 4 toxicity at any time following the second 
CD19/CD22-CAR T cell infusion that is felt to be possibly, probably or likely related to the 
CD19/CD22-CAR T cells, then reinfusions will be paused pending discussion with the FDA and 
IRB regarding continuing reinfusions as part of the experimental regimen.
3.12 OPTION FOR REMISSION MAINTENANCE
For those participants who achieve a complete remission post CAR T-cells and do not proceed 
immediately to a consolidative transplant post CAR T-cell therapy and are being monitored for 
long-term response and CAR persistence, there are well-established parameters suggestive of 
impending relapse. These metrics include a) resurgence of normal precursor B-cells 
(hematogones); b) resolution of B-cell aplasia; c) loss of CAR T-cell persistence and/or d) 
detection of minimal residual disease.  
In these circumstances, participants may have the option to receive a reinfusion or standard 
chemotherapy to maintain remission and prevent relapse, while remaining on study. This 
“maintenance” approach to remission induction is well-established in the treatment of acute 

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lymphoblastic leukemia and may include standard low-dose ALL directed maintenance-type 
chemotherapy regimens (e.g., 6-mercaptopurine, oral methotrexate, steroids and vincristine, or 
for instance utilization of a tyrosine kinase inhibitor in Ph+ ALL, amongst other standard low-
dose options). All regimens will be captured and recorded. Decisions regarding utilization of 
specific standard chemotherapeutic agents will be based on prior exposure and toxicity profile. 
If the participant chooses to receive relapse prevention therapy, the participant will be enrolled to 
protocol 04-C-0165 Oncology Care & Interventions.
Participants will be taken off-protocol as per section 3.16 if there is clear progressive disease or 
initiation of alternative therapy for treatment of disease progression, with exception for those 
participants who will be moving towards a subsequent infusion.
3.13 NEUROLOGIC AND NEUROCOGNITIVE EVALUATION
A neurologic assessment (Appendix H) will be performed as feasible, at least twice on study, 
before preparative regimen and after cell infusion (Day 28 ± 4 days) to monitor prospectively for 
signs of neurotoxicity; additional timepoints may be added per PI discretion (e.g. for those 
participants who experience cytokine release syndrome, a timepoint at the onset and resolution of 
CRS may be indicated). 
Only for those with isolated CNS disease: Additionally, a brief battery of cognitive tests 
evaluating memory, attention, processing speed, and executive functions (less than one hour to 
complete) will be administered to participants prior to anti-CD19/CD22-CAR T cell infusion and 
at timepoints given in section 15.2.2.  These tests will only be administered to subjects who 
speak English or Spanish. A parent/adult observer (or adult participant if the parent/adult 
observer is not available) also will be asked to complete a Background Information Form (about 
5 minutes to complete) and a brief neuro-symptom checklist assessing the severity and duration 
of any neurologic symptoms over the past week (about 2 minutes to complete) (Appendix H). 
The neuro-symptom checklist can be administered to parent/adult observers (or adult 
participants) who do not speak English using an interpreter. Administration of the test and neuro-
symptom checklist will be optional during reinfusion. Neuro cognitive evaluations should ideally 
be performed prior to initiation of seizure prophylaxis with levetiracetam (Keppra). See 
Appendix H for more details.
A repeat cognitive evaluation (Appendix H) will be administered at approximately 3 months 
post cell infusion (if participant returns for follow up visit) (only in participants with isolated 
CNS disease).
3.14 STUDY CALENDAR
See Appendix B: Study Calendar
3.15 PROTOCOL ACCRUAL SUSPENSION
The study will be halted, and the FDA and IRB will be notified if any of the following conditions 
are met:
•
DLT occurs in dose level -1 cohort.
•
Development of EBV lymphoma or polyclonal lymphoproliferative disease (PLPD).
•
Any Grade 5 event at least possibly related to the research product.

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3.16 TELEMEDICINE
Telemedicine is the use of interactive audio, video, audio-visual, or other telecommunications or 
electronic technology by a licensed health care practitioner to deliver clinical services. This 
protocol will allow the team to practice telemedicine to communicate with participants in real 
time, to be able to monitor and collect data, as well as the ability to share the participants’ health 
information with other health professionals. Providers may include primary providers, 
specialists/consultants and nurses. Other members of the healthcare team may also be present to 
aid with the communication devices, scheduling or records management. 
The participant or participant’s legal representative will be informed prior to the use of a 
telemedicine encounter and consent will be obtained as outlined in section 11.6.
Telemedicine visits will be arranged through our NIH Clinical Center Health Information 
Management Department and will be scheduled using NIH-approved remote platforms. 
Telemedicine visits may be used for follow-up visits if deemed appropriate by the PI. All 
telemedicine visits must be documented in CRIS like a normal onsite visit and the note should 
indicate that this visit was performed virtually.
History and Physical exams as well as vital signs, weight, performance status, adverse event 
capture as directed in in Appendix B may be completed by remote visit with a member of the 
study team (e.g., if the participant is not able to return to the NIH CC). Remote visits will be 
conducted in compliance with NIH guidelines and FDA regulations.
3.17 LOCAL EVALUATIONS
For protocol-specified timepoints post Day 28 as directed in Appendix B a participant may be 
asked to come to the NIH CC for an in-person assessment or be referred to their local provider, if 
clinically indicated, and/or at the discretion of the investigator. All physical exams, assessments, 
labs, and imaging used for follow-up or restaging visits may also be performed with the 
participant’s local physician as determined by the PI. For in-person assessments, physical 
examinations may be omitted at the discretion of the investigator. For laboratory evaluations 
conducted with local providers, interlaboratory variability is not a concern as the lab tests are all 
routine. In the case of any visits with participants’ local providers, records will be obtained for 
the research records.
3.18 COST AND COMPENSATION
3.18.1 Costs
NIH does not bill health insurance companies or participants for any research or related clinical 
care that participants receive at the NIH Clinical Center.  If some tests and procedures are 
performed outside the NIH Clinical Center, participants may have to pay for these costs if they 
are not covered by insurance company.  Medicines that are not part of the study treatment will 
not be provided or paid for by the NIH Clinical Center.
3.18.2 Compensation
Participants will receive a payment of $20 for each stool sample collected (following collection), 
up to a total of $100. Participants will only be paid for each completed stool collection. 
Compensation will be processed per NIH guidelines through Research Volunteer System. Please 
see guidance at:

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https://clinicalcenter.nih.gov/recruit/crvp/payment.html 
For pediatric participants, check will be given to a parent/guardian after each collection. 
If a participant withdraws from study, no future compensation will be made, but prior 
compensation will not be revoked. 
If a sample is collected for clinical/non-research reasons the participant will not be compensated.
3.18.3 Reimbursement 
The NCI will cover the costs of some expenses associated with protocol participation.  Some of 
these costs may be paid directly by the NIH and some may be reimbursed to the 
participant/guardian as appropriate.  The amount and form of these payments are determined by 
the NCI Travel and Lodging Reimbursement Policy.
3.19 CRITERIA FOR REMOVAL FROM PROTOCOL THERAPY AND OFF STUDY CRITERIA
Prior to removal from study, effort must be made to have all subjects complete a safety visit 
approximately 30 days following the last dose of study therapy.
3.19.1 Criteria for removal from protocol therapy
Participants will be taken off treatment (and followed until off-study criteria are met) for the 
following:
•
Treatment limiting toxicity (TLT) due to preparative regimen toxicity that precludes cell 
infusion.
•
Treatment limiting toxicity (TLT) due to cell infusion (unless criteria are met for a 
reinfusion per section 3.11). The definition of TLT is in section 3.6.1.
•
Grade 3 autoimmunity that involves vital organs (heart, kidneys, brain, eye, liver, colon, 
adrenal gland, lungs).
•
Grade 3 or 4 toxicity due to cell infusion (reaction to cellular product or infusion 
reaction) that is not reversible to a grade 2 or less within 8 hours with acetaminophen 
and/or diphenhydramine as outlined in section 3.6.1, the participant will not generally 
have the option of receiving a reinfusion of cells (unless exception is granted by the IRB 
and FDA). 
•
General or specific changes in the participant’s condition render the participant 
unacceptable for further treatment on this study in the judgment of the investigator.
•
Progressive disease (unless criteria are met for a reinfusion per section 3.11).
•
Pregnancy
•
Initiation of alternative therapy (unless criteria are met for a reinfusion per section 3.11 or 
if alternative therapy is being used to maintain remission as per section 3.12).
3.19.2 Off-Study Criteria
•
Screen Failure

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•
Participant withdrawal from protocol (in which case the reason will be documented, if 
possible)
•
Lost to follow-up
•
Death
•
Conclusion of the 15 years of long term follow up and/or participant is off therapy and 
enrolled in long-term follow up protocol for participants receiving gene therapy
•
Participant does not receive cell infusion
3.19.3 Lost to Follow-up
A participant will be considered lost to follow-up if he or she fails to return for 4 visits scheduled 
visits and is unable to be contacted by the study site staff. 
The following actions must be taken if a participant fails to return to the clinic for a required 
study visit:
•
The site will attempt to contact the participant and reschedule the missed visit within 12 
weeks and counsel the participant on the importance of maintaining the assigned visit 
schedule and ascertain if the participant wishes to and/or should continue in the study.
•
Before a participant is deemed lost to follow-up, the investigator or designee will make 
every effort to regain contact with the participant (where possible, 3 telephone calls and, 
if necessary, an IRB approved certified letter to the participant’s last known mailing 
address or local equivalent methods). These contact attempts should be documented in 
the participant’s medical record or study file.
•
Should the participant continue to be unreachable, he or she will be considered to have 
withdrawn from the study with a primary reason of lost to follow-up.
4
CONCOMITANT MEDICATIONS/MEASURES
4.1
CONCURRENT THERAPY FOR EXTRAMEDULLARY LEUKEMIA OR CNS LYMPHOMA: 
Participants must be in CNS remission or have CNS-2 disease without clinical evidence of 
cranial nerve involvement at the time of protocol enrollment. Concurrent craniospinal radiation 
will not be allowed. Concurrent therapy or prophylaxis for CNS leukemia or lymphoma 
consisting of standard intrathecal chemotherapy will be allowed as clinically indicated in 
participants with ALL at times of restaging spinal taps. Further, intrathecal chemotherapy will 
NOT be administered in any participant who develops CNS toxicity until at least 2 weeks after 
complete resolution of neurologic toxicity.
4.1.1
Regimen
The standard intrathecal chemotherapy regimen used to prevent or manage CNS relapse will be 
employed. Individual agents may be eliminated from the standard triple intrathecal (TIT)-
chemotherapy regimen based on clinical contraindications.
4.1.2
Dose
Intrathecal chemotherapy will be dosed by age according to institutional guidelines, (for 
example, the following):

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Age (years)
MTX (mg)
HDC (mg)
ARA-C (mg) Volume (ml)
3-8
12
12
24
8
>9
15
15
30
10
MTX – methotrexate; HDC – Hydrocortisone; ARA-C – cytarabine
Any combination of therapy as clinically indicated may be administered at the PI or AI’s discretion. 
4.1.3
Administration
Administration should be performed according to institutional guidelines/SOP: Delivery should 
be isovolumetric (ml CSF out = ml drug in) via lumbar puncture (LP) in the lateral decubitus 
position. Participants should remain in prone or Trendelburg position for 30 minutes post LP to 
facilitate drug circulation throughout the CNS.
4.1.3.1
History of CNS involvement post cell infusion guidelines
Intrathecal chemotherapy will NOT be administered in any participant who develops neurologic 
toxicity until at least 2 weeks after complete resolution. (exception: intrathecal hydrocortisone 
may be administered as indicated for treatment of severe neurotoxicity or intrathecal therapy 
may be administer for progressive CNS leukemia)
4.1.4
Leucovorin
Leucovorin may be given as 10 mg/m2/dose (rounded up to the nearest 5 mg increment to a 
maximum dose of 15 mg) PO or IV x 2 doses, 24 hours and 30 hours after intrathecal 
methotrexate.
4.2
INFECTION PROPHYLAXIS
Dosing of pediatric participants for infection prophylaxis will be in accordance with NIH 
Clinical Center Blood & Marrow Transplant Consortium guidelines 
(http://intranet.cc.nih.gov/bmt/clinicalcare/guidelines.shtml). Additional suggested guidelines are 
provided in Appendix J. 
Special Statement about IVIG:  Since B cell antigen-targeted immunotherapy has been 
demonstrated in other studies to also eliminate normal B cells. For this reason, it is 
recommended that serum IgG levels be monitored before cell infusion and every 3-6 weeks after 
infusion (not required). If IgG < 500, IVIG will be administered at a dose of 500 mg/kg with the 
appropriate pre-medications and per institutional guidelines as clinically indicated.
4.3
PROPHYLAXIS AND TREATMENT OF TUMOR LYSIS SYNDROME IN CHILDREN
Pediatric participants at greatest risk are those with high disease burden (e.g. bulky disease) and 
high cell turnover (e.g. elevated uric acid, LDH).
4.3.1
Regimen 
Subjects deemed to be at high risk of tumor lysis syndrome should begin allopurinol according to 
institutional standards SOP (for example: at a dose of approximately 100 mg/m2/dose p.o. TID 
(maximum dose 200 mg TID)). This should be started at least 8 hours prior to the first dose of 

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the preparative regimen and continued until disease burden is reduced (e.g. peripheral blasts 
clear) or it is apparent that no tumor lysis has developed.
Additional suggested monitoring and supportive care for subjects deemed to be at high risk of 
tumor lysis syndrome: 
•
Hydration: Starting at least 6 hours prior to initiating preparative regimen, and continuing 
for at least 24 hours after cell infusion, IV fluids should be administered at a rate of 90-
120 ml/m2/hour (1.5 – 2 times maintenance) to maintain urine specific gravity <1.010 and 
normal urine output. Potassium should be avoided. Then IV+PO should continue at 
90/m2/hour (1.5 times maintenance) until disease burden is reduced (e.g. peripheral blasts 
clear) or it is apparent that no tumor lysis has developed after at least 72 hours
•
For subjects judged to be at high risk for uric acid nephropathy, consider the use of 
rasburicase rather than allopurinol. 
For subjects with renal insufficiency, consult Nephrology. 
4.4
BLOOD PRODUCT SUPPORT
Using daily CBC’s as a guide, the participant will receive platelets and packed red blood cells 
(PRBC’s) as needed. Attempts will be made to keep Hb >8.0 gm/dl, and plts >10,000/mm3. All 
blood products with the exception of the lymphocyte product will be irradiated. Leukocyte filters 
will be utilized for all blood and platelet transfusions to decrease sensitization to transfused 
WBC’s and decrease the risk of CMV infection.
In participants with symptomatic coagulopathy, attempts will be made to keep platelets 
>50,000/mm3 and fibrinogen  the lower limit of normal. 
4.5
HYDROXYUREA
Participants receiving hydroxyurea are eligible providing the dose has been stable for at least two 
weeks prior to starting apheresis. Hydroxyurea must be discontinued at least 1 day prior to CAR 
T-cell infusion.
4.6
CYTOKINE RELEASE SYNDROME
Grading and management of CRS in this protocol will follow the guidelines in Appendix D, 
Table 3, which includes diligent supportive care and search for infection, with 
immunosuppression using anti-IL6R mAbs and/or corticosteroids reserved for more severe 
cases.
4.7
NEUROLOGIC TOXICITY 
Participants will be monitored closely with neurologic checks with vital sign according to 
institutional standards during hospitalization.  Levetiracetam (Keppra) or alternative seizure 
prophylaxis will be started anytime prior to CAR cell infusion in participants with CNS disease, 
for those at high-risk for neurotoxicity, or in those who have had a prior history of seizures, as 
per PI discretion. Adults will receive 500 mg BID, which may be escalated per standard 
guidelines to a maximum of 2 gm BID; Children will initiate levetiracetam at 20 mg/kg in 2 
divided doses (10 mg/kg BID). If levetiracetam is contraindicated, an alternative anti-seizure 
regimen may be used after discussion with the protocol team. The daily dose may be increased in 
consultation with neurology in the setting of neurotoxicity. Participants with significant 

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neurotoxicity may be treated with corticosteroids. Subjects will start levetiracetam at any time 
prior to the cell infusion and will be maintained on levetiracetam through the period of cytokine 
release syndrome. Levetiracetam may be discontinued by as early as day 21 (or after the 
resolution of CRS, whichever is later), or sooner if clinically indicated.
5
BIOSPECIMEN COLLECTION
Blood, bone marrow and CSF samples will be collected for correlative studies as outlined below 
and in Appendix I.  A single-pass apheresis may be performed if an apheresis catheter is in place 
at Day 28 ± 7 days.
5.1
CORRELATIVE STUDIES FOR RESEARCH
Note: Platforms and procedures may be adjusted based upon current technology and/or 
collaborations in place at the time of actual analyses
5.1.1
Overall goal of study correlatives 
To explore secondary and exploratory objectives on this protocol and better understand the T cell 
and tumor properties that influence CAR T cell efficacy and persistence and permit disease 
relapse and also explore the depth of treatment response and explore multiple aspects of the 
toxicity profile. 
5.1.2
Specific Aims
•
Assess the impact of T cell subset composition as delineated using flow cytometry, mass 
cytometry and ATAC-Seq on CAR T cell expansion and persistence 
•
Use exome sequencing and RNA sequencing (Shern lab POB) to analyze the correlation 
in observed changes in antigen expression at the protein level with genetic and 
transcriptional changes at the antigenic locus. Sample collection, storage and testing will 
be performed on subjects who have consented to protocol 10-C-0086 “Comprehensive 
Omics Analysis of Pediatric Solid Tumors and Establishment of a Repository for Related 
Biological Studies”.
•
Where possible, use TCR sequencing to fate map cells contained in the apheresis of 
manufactured product to persistent CD19/22-CAR T cells as an exploratory aim to 
identify subsets with a greater likelihood of T cell persistence in the setting of adoptive 
cell therapy. Sample collection, storage and testing will be performed on subjects who 
have consented to protocol 10-C-0086 “Comprehensive Omics Analysis of Pediatric Solid 
Tumors and Establishment of a Repository for Related Biological Studies”.
•
Characterize antigen expression on relapsed B-ALL and B cell lymphoma following 
multi-specific CAR-mediated targeting
•
Utilize the CAR-mediated arrest of B cell maturation to gain insight on physiologic and 
pathophysiologic B cell development, maturation arrest and alternative survival pathways 
in normal and malignant B cells. 
•
Explore the level CD19/CD22 surface expression and CD19/CD22 site density on 
leukemic blasts, when feasible and correlate with clinical response to CAR-T cells

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•
To explore CAR T-cell product characteristics that may be associated with clinical       
outcomes (e.g., CAR T-cell persistence, toxicity and/or efficacy)
•
To explore CAR T-cell expansion by T-cell subsets and immunophenotypic evaluation of 
markers of T-cell activation and/or exhaustion
5.1.3
Sequence-based detection of MRD
•
Selected participant’s samples (e.g. participants who have persistent CAR cells in the 
blood, and who appear MRD negative by flow cytometry) will have bone marrow 
samples sent to Adaptive Biotechnologies Corporation to undergo analysis by sequence-
based detection of MRD. This testing will generally be performed for research purposes 
and results will not be available in real-time. In certain circumstances, these samples may 
be sent for clinical monitoring also.   
5.1.4
Hematology studies
•
Hematology studies will include standard clinical laboratory studies, including PT/PTT, 
fibrinogen, D-Dimer, peripheral blood smear, and complement studies. 
5.1.5
Optional hematology studies to be performed only as feasible in those with evidence of 
clinically significant DIC include: 
•
Additional studies specifically for the evaluation of hemolytic uremic syndrome and/or 
thrombotic thrombocytopenic purpura and or MAS/HLH, including sMAC, and other 
complement studies, as well as ferritin and soluble IL2R.
5.1.6
Gut Microbiome (optional)
Stool samples may be obtained as outlined in Appendix I: Biospecimen Collection Schedule and 
Forms and used for gut microbiome evaluation. Analyses may include the following: 
•
Microbiome sequencing (including 16S rRNA gene sequencing, shotgun metagenomic 
sequencing, and potential evaluation of the resistome, virome, and parasitome).
•
Fecal flow (sorting and 16S and/or shotgun sequencing of IgA bound organisms, which is 
an indication of pathogenicity).
•
Lipocalin, fecal caprotectin and α-1-anti-trypsin levels (to evaluate mucosal inflammation 
and malabsorption).
•
Metabolomics (to evaluate intestinal metabolomic profiles, and when combined with 
microbiome/metagenomic studies, may suggest some functional role for candidate 
microbes of interest).
•
Measurement of secreted IgA and antimicrobial peptides.
•
Culturing/PCR for specific organisms.
•
Stool proteomics.
•
Use of stool samples in mouse models. 
•
Storage for future research.
•
Blood and urine for host responses in microbiome assessment.

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5.1.7
Metabolomic Analysis (optional)
Peripheral blood and urine samples may be collected as outlined in Appendix I  to analyze 
NAD(H), FAD(H), glutathione), amino-acids (arginine, tryptophane, glutamine, methionine), 
nucleoacids (ATP, adenosine), TCA cycle metabolites, hepcidin, Acteyl-CoA and lipids.
5.1.8
Sample Collection Schedule
The samples to be collected and schedule for sample collection is detailed in Appendix I. In 
addition, Appendix I  contains the sample information for submitting CD22 surface expression 
to the NCI for FACS analysis.
5.2
MONITORING GENE THERAPY TRIALS: PERSISTENCE, AND RCL, AND TOXICITY
The Federal Drug Administration requires monitoring of all participants who have received CAR 
therapy products. Participant’s peripheral blood samples need to be obtained and undergo 
analysis for persistence and RCL PCR including detection of p24 antigen and reverse 
transcriptase activity Product Enhanced Reverse Transcriptase [PERT]). Persistence will be 
performed by peripheral blood flow cytometry at the National Institutes of Health. RCL PCR 
testing will be performed at the Indiana University Vector Production Facility (IU VPF). For the 
purposes of this protocol, this will be considered gene-therapy follow-up.
Participants will be co-enrolled on NIH protocol 15-C-0028:  Follow-up Evaluation for Gene-
Therapy Related Delayed Adverse Events after Participation in Pediatric Oncology Branch 
Clinical Trials. Participants will have blood samples collected prior to cell infusion (at baseline) 
for RCL PCR. After infusion of CAR cells, participants will have all subsequent gene therapy 
monitoring (persistence, RCL and toxicity) completed as directed by protocol 15-C-0028. 
Note: All previously collected samples collected for RCL testing of participants on this protocol 
with this amendment (09/16/2022) will be stored at NCI-Frederick and only tested as clinically 
indicated (e.g., development of a new cancer thought to be related to therapy with CD19/22 CAR 
Tcells). If testing is required, samples will be shipped to Indiana University Vector Production 
Facility for testing.
5.3
SAMPLE STORAGE, TRACKING AND DISPOSITION
Samples will be ordered in CRIS and tracked through a Clinical Trial Data Management system.  
Should a CRIS screen not be available, the CRIS downtime procedures will be followed.  
Samples will not be sent outside NIH without appropriate approvals and/or agreements, if 
required. 
All specimens obtained in the protocol are used as defined in the protocol. Any specimens that 
are remaining at the completion of the protocol will be stored in the conditions described below. 
The study will remain open so long as sample or data analysis continues.  Samples will be stored 
until they are no longer of scientific value or if a subject withdraws consent for their continued 
use, at which time they will be destroyed. 
If the participant withdraws consent the participants data will be excluded from future 
distributions, but data that have already been distributed for approved research use will not be 
able to be retrieved.

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The PI will record any loss or unanticipated destruction of samples as a deviation. Reporting will 
be per the requirements of section 7.2.
5.3.1
Sample Data Collection
All samples sent to the Biospecimen Processing Core (BPC) will be barcoded, with data entered 
and stored in the Labmatrix utilized by the BPC. This is a secure program, with access to 
Labmatrix limited to defined BPC personnel, who are issued individual user accounts. 
Installation of Labmatrix is limited to specified computers. These computers all have a password 
restricted login screen.
Labmatrix creates a unique barcode ID for every sample and sample box, which cannot be traced 
back to participants without Labmatrix access. Data will be recorded for each sample, as 
appropriate (e.g., participant ID, name, trial name/protocol number, time drawn, cycle time point, 
dose, material type, as well as box and freezer location). Participant demographics associated 
with the Clinical Center participant number are provided in the system. For each sample, there 
are notes associated with the processing method (delay in sample processing, storage conditions 
on the ward, etc.).
5.3.2
Sample storage and Destruction
Barcoded samples are stored in barcoded boxes in a locked freezer at either -20 or -80C 
according to stability requirements.  These freezers are located onsite in the CPP and offsite at 
NCI Frederick Central Repository Services in Frederick, MD. Visitors to the laboratory are 
required to be accompanied by laboratory staff at all times. 
Access to stored clinical samples is restricted. Samples will be stored until requested by a 
researcher named on the protocol. All requests are monitored and tracked in Labmatrix. All 
researchers are required to sign a form stating that the samples are only to be used for research 
purposes associated with this trial (as per the IRB approved protocol) and that any unused 
samples must be returned to the CPP. It is the responsibility of the NCI Principal Investigator to 
ensure that the samples requested are being used in a manner consistent with IRB approval.
Following completion of this study, samples will remain in storage as detailed above. Access to 
these samples will only be granted following IRB approval of an additional protocol, granting 
the rights to use the material. 
If, at any time, a participant withdraws from the study and does not wish for their existing 
samples to be utilized, the individual must provide a written request. Following receipt of this 
request, the samples will be destroyed or returned to the participant, if so requested. The PI will 
record any loss or unanticipated destruction of samples as a deviation. Reporting will be per the 
requirements of section 7.2.
Sample barcodes are linked to participant demographics and limited clinical information. This 
information will only be provided to investigators listed on this protocol, via registered use of the 
Labmatrix. It is critical that the sample remains linked to participant information such as race, 
age, dates of diagnosis and death, and histological information about the tumor, in order to 
correlate genotype with these variables.

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The study will remain open and status reported to the NIH Intramural IRB until all samples have 
been analyzed, reported or destroyed.  Any use of these samples for purposes not described in 
this protocol will require prospective NIH Intramural IRB review and approval.
5.3.3
Hourigan Laboratory (NIAID)
Participant biospecimens, collected for the purpose of research under this protocol will be 
analyzed as per Appendix I . Samples will be tracked in the laboratory database with access 
limited to qualified study members approved by the Principal Investigator. Each team member 
accesses the database with their own individual login credentials and an audit trail tracks data 
entry and any alterations to the database. 
Sample inventory and chain of custody is tracked for all biospecimens. Samples are linked to the 
subject by the Subject ID, which cannot be traced back to the participant. Also recorded, are the 
trial name/protocol number, date obtained, current location, any derivative products, and whether 
the sample has been exhausted. All received samples will receive a unique bar code number, 
generated by the database that cannot be traced back to the participant. Vial labels do not have 
personally identifiable information for the participant. Vials will not be traceable back to 
participants without authorized access.
Samples are stored in freezers at -80°C. These freezers are located onsite at NIAID and location 
is recorded in database. Access to samples from a protocol for research purposes will be by 
permission of the Principal Investigator.
5.3.4
Taylor Laboratory (POB) 
Participant biospecimens, collected for the purpose of research under this protocol will be 
analyzed as per Appendix I. Samples will be tracked in the laboratory database with access 
limited to qualified study members approved by the Principal Investigator. Each team member 
accesses the database with their own individual login credentials and an audit trail tracks data 
entry and any alterations to the database. 
Sample inventory and chain of custody is tracked for all biospecimens. Samples are linked to the 
subject by the Subject ID, which cannot be traced back to the participant. Also recorded, are the 
trial name/protocol number, date obtained, current location, any derivative products, and whether 
the sample has been exhausted. All received samples will receive a unique bar code number, 
generated by the NCI Labmatrix database that cannot be traced back to the participant. Vial 
labels do not have personally identifiable information for the participant. Vials will not be 
traceable back to participants without authorized access.
Samples are stored in freezers at -20°C, -80°C, or -140°C/liquid nitrogen vapor phase according 
to stability requirements. These freezers are located onsite at POB and location is recorded in 
Labmatrix. Access to samples from a protocol for research purposes will be by permission of the 
Principal Investigator.
6
DATA COLLECTION AND EVALUATION 
6.1
DATA COLLECTION
The PI will be responsible for overseeing entry of data into a 21 CFR Part-11 compliant data 
capture system provided by the NCI CCR and ensuring data accuracy, consistency and 
timeliness. The principal investigator, associate investigators/research nurses and/or a contracted 

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data manager will assist with the data management efforts.  Primary and final analyzed data will 
have identifiers so that research data can be attributed to an individual human subject participant.
All adverse events, including clinically significant abnormal findings on laboratory evaluations, 
regardless of severity, will be followed until return to baseline or stabilization of event.
Document AEs from the first study intervention, Study Day -4, through day 30.  After 30 days, 
only adverse events which are serious and related to the study intervention need to be recorded.
An abnormal laboratory value will be considered an AE if the laboratory abnormality is 
characterized by any of the following:
•
Results in discontinuation from the study
•
Is associated with clinical signs or symptoms 
•
Requires treatment or any other therapeutic intervention
•
Is associated with death or another serious adverse event, including hospitalization. 
•
Is judged by the Investigator to be of significant clinical impact
•
If any abnormal laboratory result is considered clinically significant, the investigator will 
provide details about the action taken with respect to the test drug and about the 
participant’s outcome.
End of study procedures: Data will be stored according to HHS, FDA regulations, and NIH 
Intramural Records Retention Schedule as applicable. 
Loss or destruction of data: Should we become aware that a major breach in our plan to protect 
subject confidentiality and trial data has occurred, this will be reported expeditiously per 
requirements in section 7.2.1. 
6.2
DATA SHARING PLANS
6.2.1
Human Data Sharing Plan
What data will be shared?
I will share human data generated in this research for future research as follows:
•
Coded, linked data in an NIH-funded or approved public repository (clinicaltrials.gov).  
•
Coded, linked data in BTRIS (automatic for activities in the Clinical Center)
•
Identified or coded, linked data with approved outside collaborators under appropriate 
agreements.
How and where will the data be shared? 
Data will be shared through:
•
An NIH-funded or approved public repository (clinicaltrails.gov). 
•
BTRIS (automatic for activities in the Clinical Center)
•
Approved outside collaborators under appropriate individual agreements.
•
Publication and/or public presentations.
When will the data be shared?
•
Before publication.
•
At the time of publication or shortly thereafter.

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6.2.2
Genomic Data Sharing Policy
The genomic data sharing policy does not apply to this protocol as participants are co-enrolled 
on 10-C-0086 “Comprehensive Omics Analysis of Pediatric Solid Tumors and Establishment of 
a Repository for Related Biological Studies”.
6.3
RESPONSE CRITERIA
For the purposes of this study, participants should be re-evaluated for response as outlined in 
section 15.2. In addition to a baseline scan, confirmatory scans should also be obtained 4 weeks 
following initial documentation of objective response.
Response criteria are outlined in Appendix F, for participants with lymphoma and participants 
with leukemia.
6.4
TOXICITY CRITERIA
The following adverse event management guidelines are intended to ensure the safety of each 
participant while on the study.  The descriptions and grading scales found in the revised NCI 
Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 will be utilized for AE 
reporting.  All appropriate treatment areas should have access to a copy of the CTCAE version 
5.0.  A copy of the CTCAE version 5.0 can be downloaded from the CTEP website 
(http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm#ctc ). 
Cytokine release syndrome will be graded as per the grading system in Appendix D of this 
protocol.
CAR-T related neurotoxicity will be graded using CTCAE and the grading system in Appendix 
G.
7
NIH REPORTING REQUIREMENTS / DATA SAFETY MONITORING PLAN
7.1
DEFINITIONS
Please refer to definitions provided in Policy 801: Reporting Research Events found at: 
https://irbo.nih.gov/confluence/pages/viewpage.action?pageId=36241835#Policies&Guidance-
800Series-ComplianceandResearchEventReportingRequirements
7.2
OHSRP OFFICE OF COMPLIANCE AND TRAINING / IRB REPORTING
7.2.1
Expedited Reporting
Please refer to the reporting requirements in Policy 801: Reporting Research Events and Policy 
802 Non-Compliance Human Subjects Research found at: 
https://irbo.nih.gov/confluence/pages/viewpage.action?pageId=36241835#Policies&Guidance-
800Series-ComplianceandResearchEventReportingRequirements. Note: Only IND Safety 
Reports that meet the definition of an unanticipated problem or present new information that 
might affect the willingness of participants to enroll or remain on the study will need to be 
reported per these policies.
7.2.2
IRB Requirements for PI Reporting at Continuing Review
Please refer to the reporting requirements in Policy 801: Reporting Research Events found at: 
https://irbo.nih.gov/confluence/pages/viewpage.action?pageId=36241835#Policies&Guidance-
800Series-ComplianceandResearchEventReportingRequirements. 

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7.3
NCI CLINICAL DIRECTOR REPORTING
Problems expeditiously reviewed by the OHSRP in the NIH eIRB system will also be reported to 
the NCI Clinical Director/designee; therefore, a separate submission for these reports is not 
necessary.
In addition to those reports, all deaths that occur within 30 days after receiving a research 
intervention should be reported via email unless they are due to progressive disease.  
To report these deaths, please send an email describing the circumstances of the death to 
NCICCRQA@mail.nih.gov within one business day of learning of the death.
7.4
INSTITUTIONAL BIOSAFETY COMMITTEE (IBC) REPORTING CRITERIA
7.4.1
Serious Adverse Event Reports to IBC
The Principal Investigator (or delegate) will notify IBC of any unexpected fatal or life-
threatening experience associated with the use of CD19/C22 T-cells as soon as possible but in no 
event later than 7 calendar days of initial receipt of the information.  Serious adverse events that 
are unexpected and associated with the use of the CD19/C22 T-cells, but are not fatal or life-
threatening, must be reported to the NIH IBC as soon as possible, but not later than 15 calendar 
days after the investigator’s initial receipt of the information.  Adverse events may be reported 
by using the FDA Form 3500a.
7.4.2
Annual Reports to IBC
Within 60 days after the one-year anniversary of the date on which the IBC approved the initial 
protocol, and after each subsequent anniversary until the trial is completed, the Principal 
Investigator (or delegate) shall submit the information described below.  Alternatively, the IRB 
continuing review report can be sent to the IBC in lieu of a separate report.  Please include the 
IBC protocol number on the report.
7.4.2.1
Clinical Trial Information 
A brief summary of the status of the trial in progress or completed during the previous year. The 
summary is required to include the following information: 
•
the title and purpose of the trial 
•
clinical site
•
the Principal Investigator
•
clinical protocol identifiers; 
•
participant population (such as disease indication and general age group, e.g., adult or 
pediatric); 
•
the total number of participants planned for inclusion in the trial; the number entered into 
the trial to date whose participation in the trial was completed; and the number who 
dropped out of the trial with a brief description of the reasons 
•
the status of the trial, e.g., open to accrual of subjects, closed but data collection ongoing, 
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•
if the trial has been completed, a brief description of any study results. 
7.4.2.2
Progress Report and Data Analysis 
Information obtained during the previous year's clinical and non-clinical investigations, 
including: 
•
a narrative or tabular summary showing the most frequent and most serious adverse 
experiences by body system
•
a summary of all serious adverse events submitted during the past year
•
a summary of serious adverse events that were expected or considered to have causes not 
associated with the use of the gene transfer product such as disease progression or 
concurrent medications
•
if any deaths have occurred, the number of participants who died during participation in 
the investigation and causes of death
•
a brief description of any information obtained that is pertinent to an understanding of the 
gene transfer product’s actions, including, for example, information about dose-response, 
information from controlled trials, and information about bioavailability. 
7.5
NIH REQUIRED DATA AND SAFETY MONITORING PLAN
7.5.1
Principal Investigator/Research Team 
The clinical research team will meet weekly when participants are being actively treated on the 
trial to discuss each participant. Decisions about dose level enrollment and dose escalation if 
applicable will be made based on the toxicity data from prior participants. 
All data will be collected in a timely manner and reviewed by the principal investigator or a lead 
associate investigator. Events meeting requirements for expedited reporting as described in 
section 7.2.1 will be submitted within the appropriate timelines. 
The principal investigator will review adverse event and response data on each participant to 
ensure safety and data accuracy. The principal investigator will personally conduct or supervise 
the investigation and provide appropriate delegation of responsibilities to other members of the 
research staff.  
7.5.2
Safety Monitoring Committee (SMC)
This protocol will be periodically reviewed by an intramural Safety Monitoring Committee 
(SMC). Initial review will occur as soon as possible after the annual NIH Intramural IRB 
continuing review date. Subsequently, each protocol will be reviewed as close to annually as the 
quarterly meeting schedule permits or more frequently as may be required by the SMC based on 
the risks presented in the study. For initial and subsequent reviews, protocols will not be 
reviewed if there is no accrual within the review period. 
The SMC review will focus on unexpected protocol-specific safety issues that are identified 
during the conduct of the clinical trial.
Written outcome letters will be generated in response to the monitoring activities and submitted 
to the Principal investigator and Clinical Director or Deputy Clinical Director, CCR, NCI.

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8
SPONSOR SAFETY REPORTING
8.1
DEFINITIONS
8.1.1
Adverse Event 
Any untoward medical occurrence in a participant or clinical investigation subject administered a 
pharmaceutical product and which does not necessarily have a causal relationship with this 
treatment. An adverse event (AE) can therefore be any unfavorable and unintended sign 
(including an abnormal laboratory finding), symptom, or disease temporally associated with the 
use of a medicinal (investigational) product, whether or not related to the medicinal 
(investigational) product (ICH E6 (R2)).
8.1.2
Serious Adverse Event (SAE)
An adverse event or suspected adverse reaction is considered serious if in the view of the 
investigator or the sponsor, it results in any of the following:
•
Death,
•
A life-threatening adverse event (see section 8.1.3)
•
Inpatient hospitalization or prolongation of existing hospitalization
o
A hospitalization/admission that is pre-planned (i.e., elective or scheduled surgery 
arranged prior to the start of the study), a planned hospitalization for pre-existing 
condition, or a procedure required by the protocol, without a serious deterioration in 
health, is not considered a serious adverse event.
o
A hospitalization/admission that is solely driven by non-medical reasons (e.g., 
hospitalization for patient or subject convenience) is not considered a serious adverse 
event. 
o
Emergency room visits or stays in observation units that do not result in admission to 
the hospital would not be considered a serious adverse event. The reason for seeking 
medical care should be evaluated for meeting one of the other serious criteria.
•
Persistent or significant incapacity or substantial disruption of the ability to conduct 
normal life functions
•
A congenital anomaly/birth defect.
•
Important medical events that may not result in death, be life-threatening, or require 
hospitalization may be considered a serious adverse drug experience when, based upon 
appropriate medical judgment, they may jeopardize the patient or subject and may require 
medical or surgical intervention to prevent one of the outcomes listed in this definition.
8.1.3
Life-threatening 
An adverse event or suspected adverse reaction is considered "life-threatening" if, in the view of 
either the investigator or sponsor, its occurrence places the patient or subject at immediate risk of 
death. It does not include an adverse event or suspected adverse reaction that, had it occurred in a 
more severe form, might have caused death. (21CFR312.32).

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8.1.4
Severity
The severity of each Adverse Event will be assessed utilizing the CTCAE version 5.
8.1.5
Relationship to Study Product
All AEs will have their relationship to study product assessed using the terms:  related or not 
related.  
•
Related – There is a reasonable possibility that the study product caused the adverse 
event. Reasonable possibility means that there is evidence to suggest a causal relationship 
between the study product and the adverse event.
•
Not Related – There is not a reasonable possibility that the administration of the study 
product caused the event.
8.2
ASSESSMENT OF SAFETY EVENTS
AE information collected will include event description, date of onset, assessment of severity 
and relationship to study product and alternate etiology (if not related to study product), date of 
resolution of the event, seriousness and outcome. The assessment of severity and relationship to 
the study product will be done only by those with the training and authority to make a diagnosis 
and listed on the Form FDA 1572 as the site principal investigator or sub-investigator.  AEs 
occurring during the collection and reporting period will be documented appropriately regardless 
of relationship.  AEs will be followed through resolution.
SAEs will be:
•
Assessed for severity and relationship to study product and alternate etiology (if not 
related to study product) by a licensed study physician listed on the Form FDA 1572 as 
the site principal investigator or sub-investigator.
•
Recorded on the appropriate SAE report form, the medical record and captured in the 
clinical database.
•
Followed through resolution by a licensed study physician listed on the Form FDA 1572 
as the site principal investigator or sub-investigator.
For timeframe of recording adverse events, please refer to section 6.1. All serious adverse events 
recorded from the time of first investigational product administration must be reported to the 
sponsor with the exception of any listed in section 8.4. 
8.3
REPORTING OF SERIOUS ADVERSE EVENTS
Any AE that meets protocol-defined serious criteria or meets the definition of Adverse Event of 
Special Interest that require expedited reporting must be submitted immediately (within 24 hours 
of awareness) to OSRO Safety using the CCR SAE report form. Any exceptions to the expedited 
reporting requirements are found in section 8.4.
All SAE reporting must include the elements described in section 8.2.
SAE reports will be submitted to the Center for Cancer Research (CCR) at: 
OSROSafety@mail.nih.gov and to the CCR PI and study coordinator.  CCR SAE report form 

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and instructions can be found 
https://ccrod.cancer.gov/confluence/display/CCRCRO/Forms+and+Instructions. 
Following the assessment of the SAE by OSRO, other supporting documentation of the event 
may be requested by the OSRO Safety and should be provided as soon as possible.
8.4
WAIVER OF EXPEDITED REPORTING TO CCR
Expected SAEs, occurring between Day 0 and Day 28, that will not require expedited reporting 
include: 
•
Grade 1 and 2 CRS events
•
Grade 3 CRS events that do not resolve to Grade 2 in 72 hours (about 3 days)
•
Inpatient admission/hospitalization for evaluation and treatment of CRS. 
•
ICU transfer for evaluation and treatment of CRS 
CRS will be graded per 2019 ASTCT, see section 15.4.
As participants are increasingly and more routinely treated as outpatients for CAR T-cell 
therapy, inpatient admissions with fever are expected and anticipated events. Similarly, the event 
of a simple transfer to the ICU to optimize management and provide more careful monitoring, in 
and of itself, is also not unexpected.
The PI will submit a safety report of all grade 3‐5 events, regardless to causality to the study 
intervention, every 6 months. The report will include a line listing of all events including the 
PID, date of onset of the event, date of resolution of the event, date of dosing for each study 
intervention in relationship to the event, attribution of the event, grade of the event, CTCAE term 
of the event and the System Organ Class of the event. In addition, a listing of all adverse events 
including the number of participants experiencing each adverse event, cumulative and per grade, 
and per causality assessment will be included. The report will indicate the date of the data cut 
off, total number of participants treated to date, and dictionary for any coded field. The report is 
cumulative and new information for the last 6 months period should be highlighted. The report 
should be sent to OSROSafety@mail.nih.gov. 
The Sponsor might request case summaries for those events if, upon review, the Sponsor 
determines that an aggregate safety report is required (21CFR312.32(c)(1)(iv)).
8.5
SAFETY REPORTING CRITERIA TO THE PHARMACEUTICAL COLLABORATORS
Reporting will be per the collaborative agreement.
8.6
REPORTING PREGNANCY 
All required pregnancy reports/follow-up to OSRO will be submitted to: 
OSROSafety@mail.nih.gov and to the CCR PI and study coordinator.  Forms and instructions 
can be found https://ccrod.cancer.gov/confluence/display/CCRCRO/Forms+and+Instructions. 
8.6.1
Maternal exposure
If a participant becomes pregnant during the course of the study, the study treatment should be 
discontinued immediately, and the pregnancy reported to the Sponsor no later than 24 hours of 

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when the Investigator becomes aware of it. The Investigator should notify the Sponsor no later 
than 24 hours of when the outcome of the Pregnancy become known,
Pregnancy itself is not regarded as an SAE. However, congenital abnormalities or birth defects 
and spontaneous miscarriages that meet serious criteria (section 8.1.2) should be reported as 
SAEs. 
The outcome of all pregnancies should be followed up and documented.
8.6.2
Paternal exposure
Male participants should refrain from fathering a child or donating sperm during the study and 
for 4 months after the study therapy.
Pregnancy of the participant’s partner is not considered to be an AE. The outcome of all 
pregnancies occurring from the date of the first dose until 4 months after the last dose should, if 
possible, be followed up and documented. Pregnant partners may be offered the opportunity to 
participate in an institutional pregnancy registry protocol (e.g., the NIH IRP pregnancy registry 
study) to provide data about the outcome of the pregnancy for safety reporting purposes.
8.7
REGULATORY REPORTING FOR STUDIES CONDUCTED UNDER CCR-SPONSORED IND
Following notification from the investigator, CCR, the IND sponsor, will report any suspected 
adverse reaction that is both serious and unexpected.  CCR will report an AE as a suspected 
adverse reaction only if there is evidence to suggest a causal relationship between the study 
product and the adverse event.  CCR will notify FDA and all participating investigators (i.e., all 
investigators to whom the sponsor is providing drug under its INDs or under any investigator’s 
IND) in an IND safety report of potential serious risks from clinical trials or any other source, as 
soon as possible, in accordance to 21 CFR Part 312.32. 
All serious events will be reported to the FDA at least annually in a summary format.
8.8
SPONSOR PROTOCOL DEVIATION REPORTING
A Protocol Deviation is defined as any non-compliance with the clinical trial Protocol, Manual 
of Operational Procedures (MOP) and other Sponsor approved study related documents, GCP, or 
protocol-specific procedural requirements on the part of the participant, the Investigator, or the 
study site staff inclusive of site personnel performing procedures or providing services in support 
of the clinical trial.
It is the responsibility of the study Staff to document any protocol deviation identified by the 
Staff or the site Monitor in the CCR Protocol Deviation Tracking System (PDTS) online 
application. The entries into the PDTS online application should be timely, complete, and 
maintained per CCR PDTS user requirements. 
In addition, any deviation to the protocol should be documented in the participant’s source 
records and reported to the reviewing IRB per their guidelines. OSRO required protocol 
deviation reporting is consistent with E6(R2) GCP: Integrated Addendum to ICH E6(R1): 4.5 
Compliance with Protocol; 5.18.3 (a), and 5.20 Noncompliance; and ICH E3 16.2.2 Protocol 
deviations.

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9
CLINICAL MONITORING PLAN
As a sponsor for clinical trials, FDA regulations require the CCR to maintain a monitoring 
program. The CCR’s program allows for confirmation of: study data, specifically data that could 
affect the interpretation of primary and secondary study endpoints; adherence to the protocol, 
regulations, ICH E6, and SOPs; and human subjects’ protection. This is done through 
independent verification of study data with source documentation focusing on:
•
Informed consent process
•
Eligibility confirmation
•
Drug administration and accountability
•
Adverse events monitoring
•
Response assessment.
The monitoring program also extends to multi-site research when the CCR is the coordinating 
center.
This trial will be monitored by personnel employed by a CCR contractor. Monitors are qualified 
by training and experience to monitor the progress of clinical trials. Personnel monitoring this 
study will not be affiliated in any way with the trial conduct.
Clinical site monitoring is conducted to ensure:
•
that the rights of the participants are protected; 
•
that the study is implemented per the approved protocol, Good Clinical Practice and 
standard operating procedures; and, 
•
the quality and integrity of study data and data collection methods are maintained.  
Monitoring for this study will be performed by NCI CCR Office of Sponsor and Regulatory 
Oversight (OSRO) Sponsor and Regulatory Oversight Support (SROS) Services contractor. 
Clinical site monitoring activities will be based on OSRO standards, FDA Guidance E6(R2) 
Good Clinical Practice: Integrated Addendum to ICH E6(R1) March 2018, and applicable 
regulatory requirements.
Details of clinical site monitoring will be documented in a Clinical Monitoring Plan (CMP) 
developed by OSRO. CMPs will be protocol-specific, risk-based and tailored to address human 
subject protections and integrity of the study data. OSRO will determine the intensity and 
frequency of monitoring based on several factors, including study type, phase, risk, complexity, 
expected enrollment rate, and any unique attributes of the study and the site. The Sponsor will 
conduct a periodic review of the CMP to confirm the plan's continued appropriateness. A change 
to the protocol, significant or pervasive non-compliance with GCP, or the protocol may trigger 
CMP updates.
OSRO SROS Monitoring visits and related activities will be conducted throughout the life cycle 
of each protocol. The first activity is before the study starts to conduct a Site Assessment Visit 
(SAV) (as warranted), followed by a Site Initiation Visit (SIV), Interim Monitoring Visit(s) 
(IMVs), and a study Close-Out Visit (COV).
Some monitoring activities may be performed remotely, while others will occur at the study site(s). 
Monitoring visit reports will describe visit activities, observations, and associated action items or 
follow-up required for resolution of any issues, discrepancies, or deviations. Monitoring reports 

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will be distributed to the study PI, NCI CCR QA, CCR Protocol Support Office, coordinating 
center (if applicable), and the Sponsor regulatory file.
The site Monitor will inform the study team of any deviations observed during monitoring visits. 
If unresolved, the Monitor will request that the site Staff enter the deviations in the CCR Protocol 
Deviation Tracking System (PDTS) for deviation reporting to the Sponsor and as applicable per 
institutional and IRB guidance.
10 STATISTICAL CONSIDERATIONS  
10.1 STATISTICAL HYPOTHESIS
10.1.1 Primary Objective
Assess the safety of administering escalating doses of autologous CD19/CD22-CAR engineered 
T cells that can be feasibly produced to meet established release specifications in children and 
young adults with B cell ALL or lymphoma following a cyclophosphamide/fludarabine 
conditioning regimen.  
In addition to evaluating up to 6 participants at a given dose level with respect to toxicity, the 
number of participants which can successfully manufacture the targeted dose number will be 
determined. Participants will be enrolled on a given dose level until adequate participants are 
enrolled to produce the correct number of cells for safety evaluation at that dose level. 
10.1.2 Secondary Objective 
Evaluate whether CD19/CD22-CAR T cells can mediate clinical activity in children and young 
adults with B-ALL, isolated CNS ALL, or lymphoma.
10.2 SAMPLE SIZE DETERMINATION
10.2.1 Sample size related to safety endpoint
The primary objectives of this study are safety and feasibility.  Three to 6 participants will be 
enrolled in three dose cohorts to determine the maximum tolerated dose. The study will allow for 
up to 3 participants to be replaced in each of the dose cohorts 1 through 3 (9 additional 
participants) due to inability to achieve target doses, for a maximum of 27 participants. Up to 2 
extra participants may be enrolled on a single dose level, per amendment, version date 
06/10/2019. Prior to amendment, version date 01/11/2020, 4 participants had been enrolled on 
dose level 1 and 4 had been enrolled on dose level 2; participants are currently enrolling onto 
dose level 3, and with allowance for replacement of participants, up to 9 participants may be 
enrolled on dose level 3. Beginning with amendment, version date 01/11/2020, participants will 
enroll in two cohorts based on their prior CAR-T and/or transplant experience (CAR naïve or 
CAR pre-treated with an interim transplant; previous CAR-T treatment with no interim 
transplant). As a result, dose level 4 will contain up to 18 total participants (2 cohorts with up to 
9 participants per cohort). Thus, up to 4+4+9+18=35 participants may enroll in the 4 dose levels 
during dose escalation.  In addition, the study will allow for 6 total inevaluable participants 
(participants enrolled but who cannot receive cells, either due to physical deterioration or 
withdrawn consent during cell growth). Thus, 35 + 6 + 2 (2 extra participants by PI discretion, 
per amendment, version date 06/10/2019) yields a maximum of 43 participants who will be 
enrolled to determine MTD and feasible dose. If dose level 4 exceeds DLT, future participants 
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The endpoint for Safety of CD19/CD22-CAR T cells is evidenced by the incidence and severity 
of dose limiting toxicities (DLTs) (i.e. laboratory abnormalities, changes in vital signs, and 
changes in physical examination) following chemotherapy preparative regimen and infusion of 
CD19/CD22-CAR T cells, recorded and graded according to the Common Terminology Criteria 
for Adverse Events (CTCAE) Version 5 at three dose levels until the maximum tolerated dose 
(MTD) is determined.  If Dose level 3 can be feasibly manufactured and is administered in up to 
6 participants without evidence of DLT or efficacy, consideration will be given to amending the 
trial to examine higher dose levels.
The dose escalation procedure follows a 3+3 design as described in section 3.7, beginning with 
dose level 1, based on the DLT count and response rate in each cohort, with escalation also 
constrained by the feasibility of producing the doses called for. The purpose of the design is not 
to invert the dose-toxicity curve at a target DLT rate, but rather to proceed with appropriate 
caution to dose level 3, which we expect will be reached without observing any DLT. Safety 
monitoring will continue throughout the study in the expanded cohort of up to 30 participants in 
each expansion group at the final MTD (or highest dose tested).
After determining the MTD, an expansion cohort will enroll initially 15 participants at the MTD 
(or maximal dose studied) in two cohorts (one cohort will be CAR naïve or CAR pre-treated with 
an interim transplant ,and the other cohort will be those who have received prior CAR T-cells 
without an interval transplant), including up to 6  from each of the two the dose escalation 
cohorts treated at DL4, if applicable, to further define safety, persistence, efficacy and duration 
of response.  If sufficient responses occur, the two cohorts may be expanded to 30 participants 
per cohort.
Up to 12 participants will be enrolled at the MTD for cohort 2c isolated CNS disease. For 
participants with isolated CNS disease, they will be evaluated at the current dose, dose level 3 
(3x106 cells/kg) in order to explore toxicity and response. Initially 6 eligible participants will be 
enrolled and if 0/6 have a neurologic TLT and 0-1 of 6 have any other type of TLT, then this 
cohort will be expanded to 12 total participants, provided that no more than 4 participants 
cumulatively experience any TLT, in order to further describe the toxicity of the participants.
10.2.2 Sample Size Related to Feasibility Endpoint
Feasibility will be defined as the successful manufacturing of CD19/CD22-CAR T cells that 
meet established release criteria to satisfy the targeted dose level.  Although we anticipate 
reaching the targeted cell dose during manufacture, feasibility of manufacturing cells remains a 
primary objective in this participant population.  Participants will be enrolled on a given dose 
level until adequate participants are enrolled to produce the correct number of cells for safety 
evaluation at that dose level. Specifically, dose escalation will proceed as long as 3 or more of 
the first 3 to 6 participants in a dose level are able to produce adequate cells for evaluation. For 
example, this might mean that 6 to 9 participants will need to be enrolled at a dose level to result 
in 6 for the safety evaluation. However, if less than 3 of 6 participants at a given dose level are 
able to have adequate cells produced, evaluation of that level and beyond for safety and 
feasibility will not take place. If cell growth limitations preclude administration of the targeted 
cohort cell dose, the participant will receive as many cells as possible, and be considered part of 
the lower dose cohort. If a minimum of 1.0 x105 CD19/CD22-CAR-transduced T cells per kg 
cannot be obtained for infusion, the participant may be treated but will not be evaluable for 

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toxicity or response but will be considered a feasibility failure. Specifically, if after the first 6 
participants have been enrolled at a given dose level, more than 3 are unable to have adequate 
CD19/CD22-CAR T cells produced (that meet COA for infusion), accrual to that dose level will 
stop and the dose escalation phase of the study will also end, since the upper 90% one-sided 
confidence interval about 3/6 is 79.9%; thus, it would be unlikely that the true feasibility rate is 
80% or greater for a given, which would be desirable. The evaluation of participants in the 
expansion cohort will take place using the highest dose level at which feasibility, as well as 
safety, was identified. In the expansion cohorts, the fraction which are able to manufacture the 
targeted dose level will also be monitored and beginning with the 6th participant in an expansion 
cohort, if at any point fewer than half of the enrolled participants are able to manufacture an 
acceptable level of cells, the accrual to the expansion cohort will end.
Thus, 4 + 4 + 9 + 18 + 6 + 2 + 30 + 30 +12 =115 + 25 (screen failures) + (10 inevaluable) = 150 
is the accrual ceiling. The actual maximum enrolled may be reduced by up to 6 + 6 if both 
cohorts at DL4 enroll 6 evaluable participants apiece and can be included in the expansion cohort 
evaluations, which instead yields a maximum of 128 participants who may be enrolled under 
those circumstances.
Given the number of participants seeking out adoptive cell therapy trials the rate limiting factor 
at this time is the time and labor-intensive nature of manufacturing the CD19/CD22-CAR T 
cells.  We anticipate enrollment of 2-4 participants per month given the number of participants 
with B-ALL treated at the NCI.
10.3 POPULATIONS FOR ANALYSES
Modified intention to treat. All participants who receive at least a single dose of the treatment 
will be included in the analyses.
10.4 STATISTICAL ANALYSES
10.4.1 General Approach
Safety analyses will consist of reporting AEs by type of toxicity and grade for all participants 
enrolled on the study. Feasibility will be determined by identifying if adequate CD19/CD22-
CAR T cells have been produced.
10.4.2 Analysis of the Primary Endpoints
The primary endpoints are safety. Safety analyses will consist of tabulations of grades of toxicity 
by type of toxicity.
10.4.3 Analysis of the Secondary Endpoints
The secondary endpoints include feasibility and to evaluate whether CD19/CD22-CAR T cells 
can mediate clinical activity in children and young adults with B-ALL, isolated CNS ALL, or 
lymphoma.  For evaluation of feasibility, the number of participants which can successfully 
manufacture the targeted dose number will be determined. For efficacy in ALL and lymphoma 
participants, this will be evaluated in two groups of participants, those who have previously 
received CAR therapy and those that are CAR naïve. Efficacy will be important in determining if 
a phase 2 study is warranted.  

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The toxicity data for isolated CNS cohort will be summarized in a descriptive manner, and the 
response rate will be reported along with a 95% confidence interval.
A futility analysis will be conducted when 15 participants at the MTD in each group (2a and 2b) 
have reached the 28 day bone marrow assessment (for lymphoma the efficacy will be determined 
at 3 months post-CAR infusion due to the delayed treatment effect in lymphomatous disease), 
and if 5 or fewer participants have a CR, further enrollment to that group in the study will stop, 
and the 80% upper confidence limit will be formed.  This fraction will have an upper one-sided 
80% confidence limit of 0.48, which is below the desired 50% and thus would justify stopping 
accrual at this point. Assuming no futility stopping, no failure of manufacturing the required 
doses, and no DLT observed, the study will reach a maximum size of 30 participants treated at 
dose 3 in each group, and confidence intervals will be formed. With 0 DLT out of 30 
participants, based on the one-sided upper Confidence Limits, we can rule out true DLT rates as 
high as 6%, 8% and 10% with 80%, 90% and 95% confidence (respectively).
The precision of estimate of the probability of dichotomous outcomes (as measured by 90% half-
widths of two-sided 90% confidence intervals) relating to evidence for efficacy is no worse than 
0.17, under the above conditions.
Overall survival (OS) and progression-free survival (PFS) will be assessed by dose cohort. 
Progression-free survival (PFS) will be measured from the start of the preparative regimen until 
the documentation of disease progression or death due to any cause, whichever occurs first. 
Overall survival (OS) will be determined as the time from the start of the preparative regimen 
until death.
10.4.4 Safety Analyses
All participants who receive experimental treatment (non-myeloablative chemotherapy and 
CD19/CD22-CAR T cell infusion) will be analyzed for safety and efficacy.
Subjects not treated for any reason will be included in the disposition tabulation but will be 
excluded from the safety and efficacy analysis.
The safety and tolerability of CD19/CD22-CAR T cell regimen will be assessed by:
•
Suspected adverse events, and
•
Suspected serious adverse events
As evidenced by:
•
Changes in clinical laboratory tests (clinical chemistry, hematology, etc.).
•
Changes in vital signs (blood pressure, pulse, respiratory rate and body temperature).
•
Changes in physical exams. Signs and symptoms assessed may require additional testing 
as clinically indicated such as ECG, PFT, radiographic studies, etc.
•
Participant reported signs and symptoms
Safety data will be analyzed per standard methods and interpreted descriptively for each dose 
cohort. Safety data will be summarized for each dose cohort separately and for all dose cohorts 
combined. Adverse events will be assessed using the CTCAE version 5 for type and severity of 

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event. Serious Adverse Events will be summarized for each dose cohort and for all dose cohorts 
combined. Reasons for discontinuation of study therapy will be tabulated.
Laboratory testing includes hematology, serology, serum chemistry, and urinalysis. Baseline 
laboratory testing will be those results obtained prior to initiating the nonmyeloablative 
chemotherapy regimen.  The study will utilize local lab for all clinical laboratory testing. 
Laboratory data will be tabulated based on the following result class.
•
Normal: result is within the local lab normal range
•
Abnormal: result is either higher or lower than the normal range
All abnormal values will be assessed for clinical significance; clinical significance will be 
captured in the case report form. 
Vital signs collected immediately prior to receiving study drug will be the baseline vital signs. 
Observed vital sign values and change from baseline in vital signs at each visit will be 
summarized without formal statistical testing.
Vital sign result may also be tabulated based on the following result class.
•
Normal: result is within the normal range
•
Abnormal: result is either higher or lower than the normal range
All abnormal values will be assessed for clinical significance; clinical significance will be 
captured in the case report form. Number and percent of subjects within each result class will be 
tabulated by time point for each vital sign.
Findings of physical examinations will be tabulated by dose cohorts without formal statistical 
analysis.
10.4.5 Baseline Descriptive Statistics
General demographic and clinical characteristics will be reported for the participants evaluated in 
the study.
10.4.6 Planned Interim Analyses
A futility analysis will be conducted when 15 participants at the MTD in each group (or highest 
dose studied) have reached the 28 day PET imaging and/or bone marrow assessment, and if 5 or 
fewer participants have a CR, further enrollment to that group in the study will stop, with the 
upper 80% Confidence Limit of 0.476 not reaching the 0.48 minimum overall response rate 
expected for the "competing" treatment with active therapy such as autologous HCT for 
chemotherapy responsive participants of 40%. 
10.4.7 Sub-Group Analyses
None planned.
10.4.8 Tabulation of individual Participant Data
None planned.

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10.4.9 Exploratory Analyses
a) Evaluate whether participants receiving CD19/CD22-CAR T cells relapse with loss or 
diminished expression of CD19 and/or CD22. 
b) Measure persistence of CD19/CD22-CAR T cells in the blood, bone marrow and CSF, 
and explore correlations between CD19/CD22-CAR T cell properties and CAR T cell 
efficacy and persistence. 
c) Analyze alterations in early B cell development induced by immune pressure exerted via 
CD19/CD22-CAR T cells. 
d) Assess neurologic and cognitive effects of the anti-CD19/CD22-CAR engineered T cell 
infusion pre- and post-infusion. 
e) Explore the level CD19/CD22 surface expression and CD19/CD22 site density on 
leukemic blasts and correlate with clinical response to CAR-T cells
f)
Explore the role of additional hematologic evaluation to enhance our understanding of the 
hematologic diathesis that can be seen in association with CAR or cytokine mediated 
toxicity. 
g) Explore whether sequence-based genomic analysis can detect minimal residual disease 
(MRD) in participants who have persistence of CD19/CAR22+ T cells, and who are 
MRD negative by flow cytometry.
h) To retrospectively grade CRS as per the newly established ASTCT Consensus Guidelines 
that were published in 2019 COMPLETED
i)
To identify immunophenotypic changes which may predispose to non-response or relapse 
using CyTOF in paired specimens from participants enrolled on this study.
j)
To explore CAR T-cell product characteristics that may be associated with clinical       
outcomes (e.g., CAR T-cell persistence, toxicity and/or efficacy)
k) To explore CAR T-cell expansion by T-cell subsets and immunophenotypic evaluation of 
markers of T-cell activation and/or exhaustion
l)
To describe the toxicity profile, CAR T cell expansion and persistence, overall response rate, 
and overall survival after reinfusion of anti CD19/CD22 CAR T cells in participants who do 
not have active disease, but who have early loss of CAR T cells, or loss of B cell aplasia < 6 
months post initial infusion.
m) Evaluate the efficacy of siltuximab as a treatment for cytokine release syndrome and/or 
immune effector cell associated neurotoxicity syndrome.
n) Evalaute the impact of non-fludarabine based lymphodepletion on CAR T-cell efficacy, 
toxicity and CAR T-cell expansion
o) Evaluate the gut microbiome in participants receiving CAR-T therapy and correlate with 
cytokine release, neurotoxicity, infection, antibiotic use and clinical response.
p) Conduct metabolomic analysis to evaluate how metabolite levels influence efficacy of 
CAR-T cells, and toxicity in pediatric participants treated with CAR-T cell therapy.  
10.4.9.1 Statistical Analysis of Cognitive Testing Data
Brief cognitive evaluations will be conducted pre- and post-infusion to assess any changes that 
might be related to the CD19/CD22 CAR treatment.  These cognitive evaluations will consist of 
brief tests of verbal and visual memory, attention, processing speed, and executive functions.  In 
addition, we will ask one parent or adult observer (e.g., adult sibling, spouse, other close relative 
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and a brief symptom checklist to assess the severity and duration of any neurologic symptoms that 
occur post-infusion (see Appendix G:  Guidelines for Evaluation, Grading and Treatment of CAR-
T Related Neurotoxicity). 
To analyze the data for the secondary cognitive objective, paired t-tests will be used to examine 
the change in scores between the baseline and post-infusion evaluation to determine if the change 
is significantly different from zero. For the exploratory cognitive objectives, analysis of variance 
with repeated measures will be used to examine change in scores between the baseline and the 
follow-up evaluations.  In addition, correlations or analyses of variance will be computed to 
examine the relationship between cognitive scores and cytokine levels.
Note: As of this amendment 09/16/2022, neurocognitive testing will be limited to participants with 
isolated CNS disease.
10.4.9.2 Persistence of CD19/CD22-CAR T Cell Analyses
•
Measure persistence of adoptively-transferred CD19/CD22-CAR-transduced T cells in the 
blood and, where possible, the bone marrow and CSF of participants.
Peripheral blood, bone marrow aspirate, and CSF will be collected when available and separately 
analyzed for the presence of CD19/CD22-CAR T cells. The percentage of all CD3+ cells in a 
sample that are positive by flow cytometry for CD19/CD22-CAR containing T cells will be 
analyzed and reported as time from T cell infusion.
11 HUMAN SUBJECTS PROTECTIONS 
11.1 RATIONALE FOR SUBJECT SELECTION
The participants to be entered in this protocol have B cell malignancies that are refractory to 
standard therapy, and limited life expectancies. Subjects from both genders and all racial/ethnic 
groups are eligible for this study if they meet the eligibility criteria. To date, there is no 
information that suggests that differences in drug metabolism or disease response would be 
expected in one group compared to another. Efforts will be made to extend accrual to a 
representative population, but in this preliminary study, a balance must be struck between 
participant safety considerations and limitations on the number of individuals exposed to 
potentially toxic and/or ineffective treatments on the one hand and the need to explore gender 
and ethnic aspects of clinical research on the other hand. If differences in outcome that correlate 
to gender or to ethnic identity are noted, accrual may be expanded, or a follow-up study may be 
written to investigate those differences more fully.
Pregnant individuals are excluded from this study because the study agents have the potential for 
teratogenic or abortifacient effects. In addition, because there is an unknown but potential risk 
for adverse events in nursing infants secondary to treatment of the mother with the study agents, 
nursing should be discontinued.
11.2 PARTICIPATION OF CHILDREN
The age range of participants eligible for this trial is greater than or equal to 3 years of age but 
less than or equal to 39 years of age. Physicians, nurses, and multidisciplinary support teams of 
the POB, NCI and Clinical Center will provide participant care. The staff of the POB has 
expertise in the management of children with complex oncologic disorders and complications of 
therapy. Full pediatric support and subspecialty services are available at the NIH Clinical Center.

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11.3 PARTICIPATION OF SUBJECTS UNABLE TO GIVE CONSENT
Adults who are unable to consent may enroll in or be retained on this protocol because some 
participants may have disease that affects the central nervous system or cognitive ability and 
enrollment might be compromised without their involvement. In addition, the protocol offers a 
prospect of direct benefit (section 11.4) and should therefore excluding these participants would 
compromise their ability to share in the benefits of the research.  All subjects ≥ age 18 will be 
offered the opportunity to fill in their wishes for research and care and assign a substitute 
decision maker on the “NIH Advance Directive for Health Care and Medical Research 
Participation” form so that another person can make decisions about their medical care in the 
event that they become incapacitated or cognitively impaired during the course of the study. 
Capacity to consent will be evaluated by the Principal or Associate Investigator(s).  For adults, 
whose ability to consent is uncertain, The PI or AI will contact the NIH Ability to Consent 
Assessment Team (ACAT) to assess ongoing capacity of the subjects and to identify an LAR.
Please see section 11.6.1 for consent procedure.   
11.4 EVALUATION OF BENEFITS AND RISKS/DISCOMFORTS
The experimental treatment has a chance to provide clinical benefit though this is unknown. The 
risks in the investigational portion of this treatment are detailed in section 1.4. The goal of this 
study is to improve upon the number of participants who may benefit from adoptive cell therapy 
by using participants’ own transduced T-cells without the need to identify anti-tumor T-cells 
uniquely from each participant as was required in many cancer therapy protocols. The success of 
this effort cannot be predicted at this time. Because all participants in this protocol have B cell 
malignancies without curative options and limited life expectancies the potential benefit is 
thought to outweigh the potential risks. It is anticipated that this study will provide scientific 
information relevant to tumor immunotherapy.
11.4.1 Risks of CD19/CD22-CAR T Cells
Although the risk profile of CD19/CD22-CAR T Cells cannot be completely known at this time, 
the risks can be anticipated based on extensive experience with CD19-CAR T cell infusions and 
the POB NCI experience with CD22-CAR T cell infusions.  The potential significant risks are 
described in section 1.4.  The risk profile of CD19 CAR cells is well established as multiple 
groups have tested CD19 CAR T cells in leukemia and lymphoma. Results from a number of the 
trials have been published with response rates of 70-90% for acute lymphoblastic leukemia being 
reported in the majority of studies.  The majority of AEs reported as treatment-related have been 
reversible and grade 1 or 2 in severity.  Significant problems that have been considered treatment 
related, include Cytokine Release Syndrome (CRS), visual hallucinations, neurological toxicity 
including confusion, dysphasia, hallucinations and death. One episode of cardiac arrest has 
occurred, and grade 4 neutropenia has been observed outside the expected window.  
11.4.2 Risk of Apheresis 
Apheresis is a safe procedure that is routinely performed in healthy children and adults. 
Participants will be closely monitored and procedures to minimize risks and prevent side effects 
are incorporated into all aspects of the protocol. The participating sites have broad expertise to 
adequately manage side effects, including in pediatric apheresis subjects. The potential risks of 
apheresis in this trial are as follows:

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1. The most common side effects of apheresis are pain and bruising at IV sites. A central 
venous catheter may be required. Possible side effects include pain, bleeding, bruising, 
infection, thrombosis, vascular perforation, and risks associated with the sedation used 
for placement.
2. During apheresis, mild side effects from citrate anticoagulant are common and include 
chills, numbness and tingling ("pins and needles"), anxiety, muscle cramps, and nausea. 
More serious side effects due to citrate-induced hypocalcemia are uncommon and include 
low blood pressure, seizures, weakness, and tetany. Citrate reactions rapidly resolve 
when the collection is slowed down or stopped. Prophylactic IV CaCl2 and MgSO4 
infusions may be administered to donors deemed to be at high risk of citrate toxicity. 
Risks of parenteral calcium and magnesium include extravasation necrosis and 
cardiovascular effects including bradycardia and blood pressure changes. However, side 
effects are unlikely given the low rate of infusion and use of large bore catheters for 
apheresis.
3. Transient mild thrombocytopenia is common after apheresis, but bleeding is unlikely.
4. Dilutional anemia occurs during apheresis, but this is unlikely to be clinically significant. 
5. Side effects of blood draws include pain and bruising, lightheadedness, and rarely, 
fainting. 
11.4.3 Risks of the preparative regimen and supportive therapies
The chemotherapy agents and supportive medications used in this study are FDA approved 
agents with well-known toxicity profiles. Refer to section 12 for summary of toxicities.
11.4.4 Risk of Blood Sampling
Side effects of blood draws include pain and bruising, lightheadedness, and rarely, fainting. Up 
to 94 mLs of blood may be collected at any given timepoint, and up to 448 mLs of blood may be 
collected in any given 8-week period as this is necessary for participant’s safety. For pediatric 
participants, the amount of blood drawn for research purposes from pediatric participants (those 
under 18 years of age) will not exceed these limits nor exceed 5 mL/kg in a single day, and 9.5 
mL/kg over an 8 week period.
11.4.5 Risk of Urine and Stool Collection
There is no physical risk associated with urine or stool collection.
11.4.6 Electrocardiogram (EKG) and Echocardiogram
Side effects of EKG are skin irritation where EKG electrodes are placed. Side effects of an 
echocardiogram are discomfort from the transducer being firmly placed against the chest.
11.4.7 Pulmonary Function Tests (PFTs)
These tests are safe and side effects are unlikely, but may include brief light headedness or slight 
soreness of the chest.
11.4.8 Bone Marrow Biopsy
Bone marrow biopsy is minimally invasive and is typically a very safe procedure. Usually the 
hipbone is numbed with anesthesia. Using a needle, the solid and liquid portion of bone marrow 

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is taken out. This procedure causes some pain. Very rarely, infection or bleeding may occur at 
the needle site.
11.4.9 Lumbar Puncture
Risks of lumbar puncture include pain at the site where the needle goes,  in and the spinal fluid is 
taken, and headache.  There is a small risk of infection or bleeding.
11.4.10 Risk of Central Venous Catheter (CVC)
Risks include bleeding, bruising, blood clot or infection at the site where the catheter is put in.  
In rare cases, placing a CVC has resulted in collapse of a lung.  If this happens, the lung would 
be quickly re-inflated using a tube put into your chest. Sometimes catheters may become infected 
or clogged. If this happens the catheter may need to be replaced. The CVC will be flushed once a 
day to prevent it from becoming clogged. The nursing staff will show you how to do this 
yourself when you return home.
11.4.11 Risk of Cognitive Testing
Participants may experience feelings of frustration while taking the tests.  The tests are meant to 
be challenging.  Participants will be able to take breaks as necessary.
11.4.12 Risk of MRI
People are at risk for injury from the MRI magnet if they have some kinds of metal in their body.  
It may be unsafe to have an MRI scan if a participant has pacemakers or other implanted 
electrical devices, brain stimulators, some types of dental implants, aneurysm clips (metal clips 
on the wall of a large artery), metal prostheses (including metal pins and rods, heart valves, and 
cochlear implants), permanent eyeliner, tattoos, an implanted delivery pump, or shrapnel 
fragments. Welders and metal workers may have small metal fragments in the eye. Participants 
will be screened for these conditions before having any MRI scan.  Participants who have a 
question about metal in their body, should inform the staff. Participants will be asked to 
complete an MRI screening form before each MRI scan. 
In addition, all magnetic objects (like watches, coins, jewelry, and credit cards) must be removed 
before entering the MRI scan room.
People with fear of confined spaces may become anxious during an MRI. Those with back 
problems may have back pain or discomfort from lying in the scanner.  The noise from the 
scanner is loud enough to damage hearing, especially in people who already have hearing loss. 
Everyone having a research MRI scan will be fitted with hearing protection. If the hearing 
protection comes loose during the scan, participants should let staff know right away.
There are no known long-term risks of MRI scans.
11.4.13 Risks of gadolinium enhanced MRI 
Mild symptoms from gadolinium infusion occur in fewer than 1% of those who receive it and 
usually go away quickly.  Mild symptoms may include coldness in the arm during the injection, a 
metallic taste, headache, and nausea.  In an extremely small number, fewer than one in 300,000 
people, more severe symptoms have been reported including shortness of breath, wheezing, 
hives, and lowering of blood pressure. A participant should not receive gadolinium if they 

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previously had an allergic reaction to it.  Participants will be asked about such allergic reactions 
before gadolinium is given.   
People with kidney disease are at risk for a serious reaction to gadolinium contrast called 
“nephrogenic systemic fibrosis (NSF)”.  This condition always involves the skin and can also 
involve the muscles, joints and internal organs.  NSF has resulted in a very small number of 
deaths.  A blood test of the kidney function may be done within the month before an MRI scan 
with gadolinium contrast. Participants will not receive gadolinium for a research MRI scan if 
their kidney function is below the safe level. 
Most of the gadolinium contrast leaves the body in the urine.  However, the FDA has issued a 
safety alert that indicates small amounts of gadolinium may remain in the body for months to 
years.  The long-term effects of the retained gadolinium are not unknown.  Some types of 
gadolinium contrast drugs are less likely to remain in the body than others.  In this study, we will 
use the gadolinium contrast drugs that are less likely to remain in the body. In this study, we will 
use the gadolinium contrast drugs that are less likely to remain in the body, whenever possible. 
Additional information called a “Medication Guide” will be given to all participants.  Upon 
request, staff will give participants individual information about retained gadolinium that is seen 
on their studies.
11.4.14 Scans and Contrast
The radiation risks of the PET/CT, and  CT scans are discussed below.  In addition to radiation 
risks, these scans that employ contrast may cause allergic reactions, injection site reactions 
abdominal discomfort and fainting. MRIs carry no radiation risks, but are contraindicated in 
subjects with metal in their bodies. In subjects that receive gadolinium contrast with MRIs, 
allergic reactions, injection site reactions and kidney damage may occur. 
An IV line may need to be inserted for administration of the contrast agent or anesthetic, which 
may cause pain at the site where the IV is placed and there is a small risk of bruising or infection.
11.4.15 Risks of exposure to ionizing radiation 
In this research study subjects with lymphoma or extramedullary ALL may have up to five CT 
scans and five PET/CT scans performed (inclusive of screening and treatment) a year. Subjects 
undergoing CT scans and PET/CT scans will be exposed up to 11.5 rem annually. This amount 
of radiation is greater than the NIH Radiation Guidelines of 0.5 rem per year for participants less 
than 18 years old. This level of exposure is associated with an increased risk of cancer.
11.5 RISKS/BENEFITS ANALYSIS
Participants will be monitored frequently as both inpatients and outpatients and side effects will 
be treated promptly. These measures will help to mitigate the potential risks observed with the 
preparative chemotherapy regimen and the cell administration. Prophylactic levetiracetam will 
be administered to all participants with close monitoring in the event neurologic toxicity occurs.  
The enrollment profile and dose escalation rules will help to ensure that participants are not 
exposed to unacceptable risk as a safe dose level is determined. 
Participants on this study may directly benefit from participation. It is anticipated that this study 
will provide scientific information relevant to tumor immunotherapy. Participation of adult 

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subjects, including those who may be become unable to consent also involves greater than 
minimal risk but presents the prospect for direct benefit.
11.6 CONSENT AND ASSENT PROCESS AND DOCUMENTATION
The informed consent document will be provided as a physical or electronic document to the 
participant or consent designee(s) as applicable for review prior to consenting.  A designated 
study investigator will carefully explain the procedures and tests involved in this study, and the 
associated risks, discomforts and benefits. In order to minimize potential coercion, as much time 
as is needed to review the document will be given, including an opportunity to discuss it with 
friends, family members and/or other advisors, and to ask questions of any designated study 
investigator. A signed informed consent document will be obtained prior to entry onto the study.
The initial consent process as well as re-consent and consent for telehealth visits, when required, 
may take place in person or remotely (e.g., via telephone or other NIH approved remote platforms 
used in compliance with policies, including HRPP Policy 303) per discretion of the designated 
study investigator and with the agreement of the participant/consent designee(s).  Whether in 
person or remote, the privacy of the subject will be maintained. Consenting investigators (and 
participant/consent designee, when in person) will be located in a private area (e.g., clinic consult 
room). When consent is conducted remotely, the participant/consent designee will be informed of 
the private nature of the discussion and will be encouraged to relocate to a more private setting if 
needed. 
Consent will be documented with required signatures on the physical document (which includes 
the printout of an electronic document sent to participant) or as described below, with a manual 
(non-electronic) signature on the electronic document. When required, witness signature will be 
obtained similarly as described for the investigator and participant as described below. 
Manual (non-electronic) signature on electronic document
When a manual signature on an electronic document is used for the documentation of consent at 
the NIH Clinical Center, this study will use the following to obtain the required signatures:
•
Adobe platform (which is not 21 CFR Part 11 compliant); or, 
•
iMedConsent platform (which is 21 CFR Part 11 compliant)
During the consent process, participants and investigators will view individual copies of the 
approved consent document on screens at their respective locations (if remote consent); the same 
screen may be used when in the same location but is not required.  
Both the investigator and the subject will sign the document using a finger, stylus or mouse. 
Note: Refer to the CCR SOP PM-2, Obtaining and Documenting the Informed Consent Process 
for additional information (e.g., verification of participant identity when obtaining consent 
remotely) found at:
https://ccrod.cancer.gov/confluence/pages/viewpage.action?pageId=73203825.
11.6.1 Consent Process for Adults Who Lack Capacity to Consent to Research Participation
For participants addressed in section 11.3, an LAR will be identified consistent with Policy 403 
and informed consent obtained from the LAR, as described in section 11.6.

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11.6.2 Consent Process for Minors
Consent will be obtained from parent(s)/guardians of minor children as described in section 11.6.
Where deemed appropriate by the clinician and the child’s parent(s) or guardian, the child will be 
included in all discussions about the trial and age-appropriate language will be used to describe 
the procedures and tests involved in this study, along with the risks, discomforts and benefits of 
participation. The assent process will take place in conjunction with consent; therefore, in person 
and remote assent are permitted under the same circumstances as in person and remote consent. 
Verbal assent will be obtained as appropriate for children ages > 7. Children under the age of 18, 
but who are age 12 or older will be asked to sign an age appropriate assent form if available in 
the participant’s language; otherwise, the appropriate line on the adult consent document (in the 
minor participant’s language) may be used. Children under the age of 7 years will not be 
required to provide assent as they typically do not have the cognitive ability to fully understand 
the nature of research. The consent/assent process will be documented in the child’s medical 
record, including the assessment of the child’s ability to provide assent (verbal) as applicable.  
11.6.3 Consent for minors when they reach the age of majority 
When a pediatric subject reaches age 18, continued participation (including ongoing interactions 
with the subject or continued analysis of identifiable data) will require that consent be obtained 
from the now adult with the standard protocol consent document to ensure legally effective 
informed consent has been obtained. We request waiver of informed consent for those 
individuals who become lost to follow up or who have been taken off study prior to reaching the 
age of majority.
Requirements for Waiver of Consent consistent with 45 CFR 46.116 (d):
•
The research involves no more than minimal risk to the subjects.
o
Analysis of samples and data from this study involves no additional risks to 
subjects.
•
The waiver or alteration will not adversely affect the rights and welfare of the subjects.
o
Retention of these samples or data does not affect the welfare of subjects. 
•
The research could not practicably be carried out without the waiver or alteration.
o
Considering the length of time between the minor’s last contact with the research 
team and their age of majority, it will likely be very difficult to locate them 
again.  A significant reduction in the number of samples analyzed is likely to 
impact the quality of the research. 
•
Whenever appropriate, the subjects will be provided with additional pertinent information 
after participation.
o
We only request a waiver of consent for those subjects who have been lost to 
follow-up or who have been taken off study prior to reaching the age of majority.
11.6.4 Request for Waiver of Consent for Screening Activities
Prior to the subject signing the consent for this study pre-screening activities listed in section 
2.3.1 may be performed. 

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We request a waiver of consent for these activities as they involve only minimal risk to the 
subjects.  A waiver will not adversely affect the rights and welfare of the subjects given that the 
activities are only intended to determine suitability for screening for participation in research 
protocols.  These activities could not practicably be carried out without the wavier as central 
recruiting services, utilized in the NIH Clinical Center, perform pre-screening activities for 
multiple studies and obtaining consent for each one is beyond their resources.  The subjects will 
be provided with additional pertinent information after participation as they will be informed 
whether or not they are eligible to sign a consent for additional screening.
12 REGULATORY AND OPERATIONAL CONSIDERATIONS
12.1 STUDY DISCONTINUATION AND CLOSURE
This study may be temporarily suspended or prematurely terminated if there is sufficient 
reasonable cause.  Written notification, documenting the reason for study suspension or 
termination, will be provided by the suspending or terminating party to study participants, 
investigator, funding agency, the Investigational New Drug (IND) or Investigational Device 
Exemption (IDE) sponsor and regulatory authorities.  If the study is prematurely terminated or 
suspended, the Principal Investigator (PI) will promptly inform study participants, the 
Institutional Review Board (IRB), and sponsor and will provide the reason(s) for the termination 
or suspension.  Study participants will be contacted, as applicable, and be informed of changes to 
study visit schedule.
Circumstances that may warrant termination or suspension include, but are not limited to:
•
Determination of unexpected, significant, or unacceptable risk to participants
•
Demonstration of efficacy that would warrant stopping   
•
Insufficient compliance to protocol requirements
•
Data that are not sufficiently complete and/or evaluable
•
Determination that the primary endpoint has been met
•
Determination of futility
Study may resume once concerns about safety, protocol compliance, and data quality are 
addressed, and satisfy the sponsor, IRB and as applicable, Food and Drug Administration (FDA).
12.2 QUALITY ASSURANCE AND QUALITY CONTROL
Each clinical site will perform internal quality management of study conduct, data and biological 
specimen collection, documentation and completion.  An individualized quality management 
plan will be developed to describe the site’s quality management.
Quality control (QC) procedures will be implemented beginning with the data entry system and 
data QC checks that will be run on the database will be generated. Any missing data or data 
anomalies will be communicated to the site for clarification/resolution.
Following written Standard Operating Procedures (SOPs), the monitors will verify that the 
clinical trial is conducted and data are generated and biological specimens are collected, 
documented (recorded), and reported in compliance with the protocol, International Council for 
Harmonisation Good Clinical Practice (ICH GCP), and applicable regulatory requirements (e.g., 
Good Laboratory Practices (GLP), Good Manufacturing Practices (GMP)). 

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The investigational site will provide direct access to all trial related sites, source data/documents, 
and reports for the purpose of monitoring and auditing by the sponsor, and inspection by local 
and regulatory authorities.
12.3 CONFLICT OF INTEREST POLICY
The independence of this study from any actual or perceived influence, such as by the 
pharmaceutical industry, is critical.  Therefore, any actual conflict of interest of persons who 
have a role in the design, conduct, analysis, publication, or any aspect of this trial will be 
disclosed and managed. Furthermore, persons who have a perceived conflict of interest will be 
required to have such conflicts managed in a way that is appropriate to their participation in the 
design and conduct of this trial.  The study leadership in conjunction with the National Cancer 
Institute has established policies and procedures for all study group members to disclose all 
conflicts of interest and will establish a mechanism for the management of all reported dualities 
of interest.
12.4 CONFIDENTIALITY AND PRIVACY
Participant confidentiality and privacy is strictly held in trust by the participating investigators, 
their staff, and the sponsor(s). This confidentiality is extended to cover testing of biological 
samples and genetic tests in addition to the clinical information relating to participants. 
Therefore, the study protocol, documentation, data, and all other information generated will be 
held in strict confidence. No information concerning the study or the data will be released to any 
unauthorized third party without prior written approval of the sponsor. 
All research activities will be conducted in as private a setting as possible.
The study monitor, other authorized representatives of the sponsor, representatives of the 
Institutional Review Board (IRB), and/or regulatory agencies may inspect all documents and 
records required to be maintained by the investigator, including but not limited to, medical 
records (office, clinic, or hospital) and pharmacy records for the participants in this study. The 
clinical study site will permit access to such records.
The study participant’s contact information will be securely stored at the clinical site for internal 
use during the study. At the end of the study, all records will continue to be kept in a secure 
location for as long a period as dictated by the reviewing IRB, Institutional policies, or sponsor 
requirements.
Study participant research data, which is for purposes of statistical analysis and scientific 
reporting, will be stored at the CCR NCI. This will not include the participant’s contact or 
identifying information. Rather, individual participants and their research data will be identified 
by a unique study identification number. The study data entry and study management systems 
used by the CCR NCI will be secured and password protected. At the end of the study, all study 
databases will be de-identified and archived at the NIH Clinical Center.
To further protect the privacy of study participants, a Certificate of Confidentiality has been 
issued by the National Institutes of Health (NIH). This certificate protects identifiable research 
information from forced disclosure. It allows the investigator and others who have access to 
research records to refuse to disclose identifying information on research participation in any 
civil, criminal, administrative, legislative, or other proceeding, whether at the federal, state, or 
local level. By protecting researchers and institutions from being compelled to disclose 

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information that would identify research participants, Certificates of Confidentiality help achieve 
the research objectives and promote participation in studies by helping assure confidentiality and 
privacy to participants.
13 PHARMACEUTICAL INFORMATION  
13.1 CD19/CD22-CAR T CELLS 
The cells will be manufactured in the NIH DTM CCE according to cGMP practices.
Fresh or cryopreserved peripheral blood mononuclear cells (PBMC) (depending on the timing of 
apheresis relative to cell culture, patient condition and scheduling availability) will be enriched for 
T cells using a CD4/CD8 immunomagnetic bead enrichment in DTM CCE.  They will then be 
activated by co-culture with immunomagnetic particles expressing anti-CD3 and anti-CD28 mAb. 
One day following activation, replication incompetent lentiviral vector particles containing the 
CD19/CD22.BB.z construct will be added to the culture for transduction.  Cells will be incubated 
for approximately 9 days with IL-2 then harvested and administered fresh or frozen for subsequent 
infusion.  Cells will be required to meet standard release criteria including transduction efficiency 
≥10%, T cell content ≥70%, sterility and minimum levels of LPS as well as no evidence for 
replication competent lentivirus.  All procedures will take place using good manufacturing process 
guidelines.
13.1.1 How Supplied
CD19/CD22-CAR T cells will be generated from autologous PBMC.  The replication 
incompetent, bi-specific CD19/CD22-CAR lentiviral vector is manufactured by Lentigen 
Technology Incorporated. 
 Cells meeting the release criteria will be made available fresh or frozen on the day of cell 
infusion, along with a complete COA.    
13.1.2 Stability 
This cell product expires 4 hours after completion of the cell harvest.
See section 3.3 for additional information.
13.1.3 Toxicities
See section 1.2.2.2
The following events are considered expected SAEs:
•
Grade 1 and 2 CRS events
•
Grade 3 CRS events that do not resolve to Grade 2 in 72 hours (about 3 days)
•
Inpatient admission/hospitalization for evaluation and treatment of CRS. 
•
ICU transfer for evaluation and treatment of CRS 

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13.2
FLUDARABINE
13.2.1 Description
(Please refer to package insert for complete product information) Fludarabine phosphate is a 
synthetic purine nucleoside that differs from physiologic nucleosides in that the sugar moiety is 
arabinose instead of ribose or deoxyribose. Fludarabine is a purine antagonist antimetabolite. 
13.2.2 How Supplied 
Fludarabine will be purchased by the NIH Clinical Center Pharmacy from commercial sources. 
Fludarabine Phosphate is supplied in a 25 mg/I mL vial as an intravenous solution in a 50 mg 
vial or as a 50 mg vial as a fludarabine phosphate powder in the form of a white, lyophilized 
solid cake. 
13.2.3 Stability 
Following reconstitution with 2 mL of sterile water for injection to a concentration of 25 mg/ml, 
the solution has a pH of 7.7. The fludarabine powder is stable for at least 18 months at 2-80C; 
when reconstituted, fludarabine is stable for at least 16 days at room temperature. Because no 
preservative is present, reconstituted fludarabine will typically be administered within 8 hours. 
Specialized references should be consulted for specific compatibility information. Fludarabine is 
dephosphorylated in serum, transported intracellularly and converted to the nucleotide 
fludarabine triphosphate; this 2-fluoro-ara-ATP molecule is thought to be required for the drug’s 
cytotoxic effects. Fludarabine inhibits DNA polymerase, ribonucleotide reductase, DNA 
primase, and may interfere with chain elongation, and RNA and protein synthesis.
13.2.4 Storage 
Intact vials should be stored refrigerated (2-8C).
13.2.5 Administration 
Fludarabine concentrate is further diluted to a concentration between 0.04 and 1 mg/ml and is 
administered as an IV infusion in an appropriate solution over 30 minutes. To prevent undue 
toxicity the dose will be based on BSA (25 mg/m2/dose or 30 mg/m2/dose). Please see section 
3.9.2 for daily dose modifications in light if fludarabine national drug shortages. Cumulative 
dosing will not change thus toxicity profile should not change. 
13.2.6 Toxicities 
At doses of 25 mg/m2/day or 30 mg/m2/dose for 3 days (Please see section 3.9.2 for daily dose 
modifications in light if fludarabine national drug shortages. Cumulative dosing will not change 
thus toxicity profile should not change), the primary side effect is myelosuppression; however, 
thrombocytopenia is responsible for most cases of severe and life-threatening hematologic 
toxicity. Serious opportunistic infections have occurred in CLL patients treated with fludarabine. 
Hemolytic anemia has been reported after one or more courses of fludarabine with or without a 
prior history of a positive Coomb’s test; fatal hemolytic anemia has been reported. In addition, 
bone marrow fibrosis has been observed after fludarabine therapy. Other common adverse 
effects include malaise, fever, chills, fatigue, anorexia, nausea and vomiting, and weakness. 
Irreversible and potentially fatal central nervous system toxicity in the form of progressive 
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of fludarabine. More common neurologic side effects at the current doses of fludarabine include 
weakness, pain, malaise, fatigue, paresthesia, visual or hearing disturbances, and sleep disorders. 
Adverse respiratory effects of fludarabine include cough, dyspnea, allergic or idiopathic 
interstitial pneumonitis. Tumor lysis syndrome has been rarely observed in fludarabine treatment 
of CLL. 
13.3
CYCLOPHOSPHAMIDE 
(Refer to FDA-approved package insert for complete product information)
13.3.1 Description 
Cyclophosphamide is a nitrogen mustard-derivative alkylating agent. Following conversion to 
active metabolites in the liver, cyclophosphamide functions as an alkylating agent; the drug also 
possesses potent immunosuppressive activity. The serum half-life after IV administration ranges 
from 3-12 hours; the drug and/or its metabolites can be detected in the serum for up to 72 hours 
after administration. 
13.3.2 How Supplied 
Cyclophosphamide will be obtained from commercially available sources by the NIH Clinical 
Center Pharmacy.
13.3.3 Stability 
Following reconstitution as directed with sterile water for injection, cyclophosphamide is stable 
for 24 hours at room temperature or 6 days when kept at 2-80C. 
13.3.4 Administration 
It will be diluted in an appropriate solution and infused over one hour. The dose will be based on 
the participant’s body weight, as specified in section 3.9.2.2.
13.3.5 Toxicities 
Hematologic toxicity occurring with cyclophosphamide usually includes leukopenia and 
thrombocytopenia. Anorexia, nausea and vomiting, rash and alopecia occur, especially after 
high-dose cyclophosphamide; fever, bone marrow failure, diarrhea, hemorrhagic colitis, 
infertility, and mucosal and oral ulceration have been reported. Sterile hemorrhagic cystitis 
occurs in about 20% of patients; severity can range from microscopic hematuria to extensive 
cystitis with bladder fibrosis. Although the incidence of hemorrhagic cystitis associated with 
cyclophosphamide appears to be lower than that associated with ifosfamide, mesna (sodium 2-
mercaptoethanesulfonate) has been used prophylactically as a uroprotective agent in patients 
receiving cyclophosphamide. Prophylactic mesna is not effective in preventing hemorrhagic 
cystitis in all patients. Patients who receive high dose cyclophosphamide may develop interstitial 
pulmonary fibrosis, which can be fatal. Hyperuricemia due to rapid cellular destruction may 
occur, particularly in patients with hematologic malignancy. Hyperuricemia may be minimized 
by adequate hydration, alkalinization of the urine, and/or administration of allopurinol. If 
allopurinol is administered, patients should be watched closely for cyclophosphamide toxicity 
(due to allopurinal induction of hepatic microsomal enzymes). At high doses, cyclophosphamide 
can result in a syndrome of inappropriate antidiuretic hormone secretion; hyponatremia with 
progressive weight gain without edema occurs. At high doses, cyclophosphamide can result in 

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cardiotoxicity. Deaths have occurred from diffuse hemorrhagic myocardial necrosis and from a 
syndrome of acute myopericarditis; in such cases, congestive heart failure may occur within a 
few days of the first dose. Other consequences of cyclophosphamide cardiotoxicity include 
arrhythmias, potentially irreversible cardiomyopathy, and pericarditis. Other reported adverse 
effects of cyclophosphamide include headache, dizziness, and myxedema; faintness, facial 
flushing, and diaphoresis have occurred following IV administration. Mesna (sodium 2-
mercaptoethanesulphonate; given by IV injection) is a synthetic sulfhydryl compound that can 
chemically interact with urotoxic metabolites of cyclophosphamide (acrolein and 4-
hydroxycyclophosphamide) to decrease the incidence and severity of hemorrhagic cystitis. 
Also, the alcohol content of cyclophosphamide injection should be taken into account when 
given to pediatric participants. 
13.4 PENTOSTATIN
Pentostatin is an inhibitor of the enzyme adenosine deaminase, leading to cytotoxicity through 
disruption of DNA synthesis. Refer to FDA-approved package insert for complete product 
information. Please refer to package insert for more details. 
13.4.1 Source
Commercially available and will be purchased by the NIH CC Pharmacy Department.
13.4.2 Administration 
Recipients will receive hydration with pentostatin as specified in section 3.9.2.
13.4.3 Toxicities
Because pentostatin is rarely associated with neurotoxicity (seizures, ataxia, encephalitis), 
special attention should be paid towards evaluating central nervous system toxicity.
13.5 SUPPORTIVE THERAPIES
13.5.1 Mesna 
(Sodium 2-mercaptoethanesulfonate, Mesnum, Mesnex, NSC-113891) (Please refer to the FDA-
approved package insert for complete product information)
13.5.1.1 Description 
Mesna will be obtained commercially by the Pharmacy Department of the participating site and 
is supplied as a 100 mg/ml solution. 
13.5.1.2 Storage 
Intact ampoules are stored at room temperature. 
13.5.1.3 Stability 
Diluted solutions for IV administration (1 to 20 mg/mL) are physically and chemically stable for 
at least 24 hours under refrigeration. Mesna is chemically stable at room temperature for 48-72 
hours in D5W, 48-72 hour in D5W/0.45% NaCl, or 24 hours in 0.9% sodium chloride. 
Mesna IV solution may also be administered orally. To decrease sulfur odor, parenteral solution 
should be diluted 1:1 to 1:10 in water, carbonated cola drinks, fruit juices (grape, apple, tomato, 

9 7
A b brevi ate d Title: C D 1 9/ C D 2 2 T-cell i n Pe ds
Versi o n D ate: N ove m ber 1 9, 2 0 2 4
ora n ge), or plai n or c h oc olate mil k. Mes na I V s ol uti o n is sta ble f or at least 9 da ys u n dil ute d i n 
p ol y pr o p yle ne s yri n ges a n d st ore d at r o o m te m perat ure. O nce dil ute d f or oral a d mi nistrati o n, 
mes na i njecti o n is sta ble f or 2 4 h o urs at 5 de grees Celsi us.
1 3. 5. 1. 4 A d mi nistrati o n 
F or I V a d mi nistrati o n, mes na I V s ol uti o n s h o ul d be dil ute d t o c o nce ntrati o ns less t ha n or e q ual t o 
2 0 m g mes na/ ml fl ui d i n D 5 W or n or mal sali ne a n d t o be a d mi nistere d i ntra ve n o usl y eit her as a 
c o nti n u o us i nf usi o n or as a n I V b ol us. 
F or oral a d mi nistrati o n, mes na I V s ol uti o n s h o ul d be dil ute d i n water, car b o nate d c ola dri n ks, 
fr uit j uice, or plai n or c h oc olate mil k pri or t o i n gesti o n t o i m pr o ve palata bilit y. If a patie nt 
v o mits wit hi n 2 h o urs of a n oral mes na d ose, t he d ose s h o ul d be re peate d, or t he patie nt s h o ul d 
recei ve I V mes na i nstea d.
1 3. 5. 1. 5 T o xicities
T o xicities i ncl u de na usea, v o miti n g a n d diarr hea. 
1 3. 5. 2 le vetiraceta m ( Ke p pra)
( Please refer t o t he F D A-a p pr o ve d pac ka ge i nsert f or c o m plete pr o d uct i nf or mati o n)
1 3. 5. 2. 1 Descri pti o n 
Le vetiraceta m will be o btai ne d c o m merciall y b y t he P har mac y De part me nt.  Le vetiraceta m is a n 
a ntie pile ptic dr u g a vaila ble as 2 5 0 m g ( bl ue), 5 0 0 m g ( yell o w), 7 5 0 m g ( ora n ge), a n d 1 0 0 0 m g 
( w hite) ta blets a n d as a clear, c ol orless, gra pe-fla v ore d li q ui d ( 1 0 0 m g/ m L) f or oral 
a d mi nistrati o n.
T he c he mical na me of le vetiraceta m, a si n gle e na nti o mer, is ( S)- ￿￿2- o x o p yrr oli di n- 1-
yl) b uta na mi de, its m olec ular f or m ula is C 8H 1 4N 2O 2 a n d its m olec ular wei g ht is 1 7 0. 2 1.
T he precise mec ha nis m(s) b y w hic h le vetiraceta m e xerts its a ntie pile ptic effect is u n k n o w n.
1 3. 5. 2. 2 St ora ge 
St ore at 2 5 °C ( 7 7 °F); e xc ursi o ns per mitte d t o 1 5- 3 0 °C ( 5 9- 8 6 °F).
1 3. 5. 2. 3 A d mi nistrati o n 
See pac ka ge i nsert f or a d mi nistrati o n preca uti o ns
1 3. 5. 2. 4 T o xicities
T he m ost c o m m o n t o xicities i ncl u de s o m n ole nce, acci de ntal i nj ur y, h ostilit y, ner v o us ness a n d 
ast he nia.  V o miti n g a n d a n ore xia ha ve als o bee n re p orte d.
1 3. 5. 3
Aceta mi n o p he n ( T yle n ol) 
Will be gi ve n as a pre- me dicati o n. T his a ge nt will be pr o vi de d b y t he P har mac y De part me nt of 
t he partici pati n g site. Please refer t o t he pac ka ge i nsert f or c o m plete p har mace utical i nf or mati o n 
o n t his pr o d uct.

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13.5.4 Diphenhydramine (Benadryl) 
Will be given as a pre-medication IV over 10-15 minutes. This agent will be provided by the 
Pharmacy Department of the participating site. Please refer to the package insert for complete 
pharmaceutical information on this product.
13.5.5 Intrathecal Chemotherapy 
The following agents will be provided by the Pharmacy Department of the participating site. 
Please refer to the package inserts for complete pharmaceutical information on these products.
13.5.5.1 Hydrocortisone (Cortef, Solu-cortef) NCS# 010483
13.5.5.1.1 Source and Pharmacology 
Synthetic steroid akin to the natural adrenal hormone, cortisol. It binds with steroid receptors on 
nuclear membrane, impairs cellular mitosis and inhibits protein synthesis. It is phase specific, 
killing cells primarily during S phase. It has a catabolic effect on proteins and alters the kinetics 
of peripheral blood leukocytes. It is excreted in the urine and catabolized in the liver.
13.5.5.1.2 Toxicity
The following toxicities may occur when hydrocortisone is given intrathecally: Nausea and 
vomiting, headache, pleocytosis, fever, somnolence, meningismus, learning disability, 
leukoencephalopathy.
13.5.5.1.3 Formulation and Stability
Available as 100mg, 250mg, 500mg, and 1000mg vials for aqueous injection. In powder form, 
the drug is stable for 2 years at room temperature. After reconstitution, it is stored at room 
temperature, and should be discarded after 3 days. INTRATHECAL ADMINISTRATION: IT 
hydrocortisone should be further diluted with physiologic buffered diluents (lactated Ringer's, 
0.9% sodium chloride, Elliott’s B solution). Do not use Bacteriostatic Water to reconstitute for 
IT use, use only preservative free solutions.
13.5.5.1.4 Guidelines for Administration
Hydrocortisone will be given by intrathecal administration in an age-specified dose and will be 
mixed with the other agents to the age-specified volume. (section 4.1)
13.5.5.1.5 Supplier
Commercially Available.
13.5.5.2 Cytarabine (cytosine arabinoside, AraC, Cytosar) NSC# 063878
13.5.5.2.1 Source and Pharmacology
Deoxycytidine analogue which is metabolized to ARA-CTP, a substance which inhibits DNA 
polymerase. It is S phase specific, and thus affects DNA synthesis. Rapidly catabolized by hepatic 
cytidine deaminases to AraU.
13.5.5.2.2 Toxicity
The following toxicities may occur when cytarabine is given intrathecally: Nausea, vomiting, 
headache, pleocytosis, arachnoiditis, rash, fever, somnolence, meningismus, convulsions, 

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paresis, myelosuppression, ataxia, learning disability. CNS impairment may not be fully 
reversible. No further cytarabine will be administered if there is CNS toxicity (any grade) 
deemed related to cytarabine.
13.5.5.2.3 Formulation and Stability
A freeze-dried powder available in 100mg, 500mg, 1g and 2g vials. The unreconstituted form of 
the drug is stable at room temperature for at least 2 years. INTRATHECAL 
ADMINISTRATION: IT cytarabine should be further diluted with physiologic buffered diluents 
(lactated Ringer's, 0.9% sodium chloride, Elliott’s B solution). Do not use Bacteriostatic Water 
to reconstitute for IT use, use only preservative free solutions.
13.5.5.2.4 Guidelines for Administration
Cytarabine will be given by intrathecal administration in an age-specified dose and will be mixed 
with the other agents to the age-specified volume (section 4.1.2). If emesis occurs, it usually 
occurs 4-6 hours after the intrathecal administration. If the patient has had emesis with prior 
intrathecal chemotherapy, premedications should be considered.
13.5.5.2.5 Supplier
Commercially available. See package insert for further information.
13.5.5.3 Methotrexate
13.5.5.3.1 Source and Pharmacology
Methotrexate is an antimetabolite and antifolate agent with antineoplastic and 
immunosuppressant activities. Methotrexate binds to and inhibits the enzyme dihydrofolate 
reductase, resulting in inhibition of purine nucleotide and thymidylate synthesis and, 
subsequently, inhibition of DNA and RNA syntheses. Methotrexate also exhibits potent 
immunosuppressant activity although the mechanism(s) of actions is unclear.
13.5.5.3.2 Toxicity
The following toxicities may occur when given intrathecally: occasional headache, dizziness, 
tiredness, blurred vision or loss of balance for a few hours. Up to 15% of children may develop 
neurological changes including changes in level of consciousness, abnormal movements or 
confusion, very rarely leukoencephalopathy. 
13.5.5.3.3 Formulation and Stability
Methotrexate Sodium Injection USP is available for single use only in 20 mg and 1 gram vials, 
and will be diluted according to TIT in section 4.1. Dilutions should be used within 24 hours if 
kept at room temperature. Unused solution should be discarded after this time in order to avoid 
risk of microbial contamination. INTRATHECAL ADMINISTRATION: IT methotrexate should 
be further diluted with physiologic buffered diluents (lactated Ringer's, 0.9% sodium chloride, 
Elliott’s B solution). Do not use Bacteriostatic Water to reconstitute for IT use, use only 
preservative free solutions.
13.5.5.3.4 Preparation 

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The three agents will be filtered and mixed in sterile preservative free 0.9% sodium chloride 
immediately (less than 4 hrs) prior to administration. The final concentration should be no 
greater than 1.5mg/ml for MTX and HDC, and 3 mg/ml for Ara-C.
13.5.5.3.5 Guidelines for Administration
Methotrexate will be given by intrathecal administration in an age-specified dose and will be 
mixed with the other agents to the age-specified volume (section 4.1.2). If emesis occurs it 
usually occurs 4-6 hours after the intrathecal administration. If the patient has had emesis with 
prior intrathecal chemotherapy, premedications should be considered.
13.5.5.3.6 Supplier
Commercially available. See package insert for further information.
13.5.6 Allopurinol
Allopurinol will be obtained by the Pharmacy Department of the participating site. It will be used 
as prophylaxis or treatment of pediatric patients with or at high risk for Tumor Lysis Syndrome. 
Dosage is approximately 100 mg/m2/dose p.o. TID (maximum dose 200 mg TID). The most 
common side effects include hypersensitivity, rash, nausea, vomiting, renal insufficiency, and 
hepatic dysfunction. Allopurinol should be stopped immediately if rash develops. Consult the 
package insert for a complete list of all side effects.
13.5.7 Tocilizumab (ACTEMRA)
Will be given per Appendix D. This agent will be provided by the Pharmacy Department. Please 
refer to the package insert for complete pharmaceutical information on this product.
13.5.8 Siltuximab (Sylvant)
Will be given per Appendix D. this agent will be provided by the Pharmacy Department. Please 
refer to the package insert for complete pharmaceutical information on this product.

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15 APPENDICES
15.1 APPENDIX A: PERFORMANCE STATUS CRITERIA

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15.2 APPENDIX B: STUDY CALENDARS
Subjects will have clinical evaluations completed per the following guidelines with the exception noted below:
Exception #1
•
If during the first restaging evaluation, the subject experiences no response (i.e., progressive disease) and no ongoing toxicity 
then no further clinical evaluations or follow-up is required. Participants will be followed for gene-therapy follow-up only (see 
section 5.2).  
Note:
•
Once a participant develops PD or goes on to other therapies (including, but not limited to hematopoietic stem cell transplant), 
participants will be followed for Gene therapy follow-up ONLY (see section  5.2). It will include evaluations for persistence of 
Anti-CD19/22 CAR T-cells in blood samples, detection of RCL and long-term follow-up for toxicity assessment. This follow-
up will be performed as dictated in NIH protocol 15-C-0028.

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15.2.1 Appendix B 1:  General Clinical Calendar
Pre-Cell 
Infusion
Lymphodepleting 
Chemotherapy
CAR 
Infusion
Post CAR (Days 1-28)
Post CAR Follow-up
(Month 2 and beyond)
PROCEDURE
ScreeningA
BaselineB
Day -5
Day -4
Day -3
Day -2
Day 0
Day 1 – Day 7
Day 8 – Day 14
Day 15 – Day 21
Day 22- Day 28
Day 28 ( 4 days)BB
Month 2 ( 2 weeks)S
Months 3 ( 2 weeks)
Month 6 ( 2 months)
Month 12 ( 3 months)
Month 18 and 24
( 6 months)
Yearly ( 6 months)
History and PE
X
X
X
XG
XG
XG
XG
X
X
X
X
X
X
X
Vital Signs
X
X
XC
XG
XG
XG
XG
X
X
X
X
X
X
X
Performance Status
X
X
X
X
X
Height
X
X
X
Weight
X
X
X
X
ECG
X
ECHO or cardiac MRI
X
Pulse oximetry and/or 
Pulmonary Function 
Testing
XD
CD19-CD22 Expression
X
HIV, HbsAg, Anti-
HCV antibodies
X
DTM Viral Markers 
(Transplant donor) and 
Rapid Plasma Reagin 
(RPR) required by 
DTM
XV

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Pre-Cell 
Infusion
Lymphodepleting 
Chemotherapy
CAR 
Infusion
Post CAR (Days 1-28)
Post CAR Follow-up
(Month 2 and beyond)
PROCEDURE
ScreeningA
BaselineB
Day -5
Day -4
Day -3
Day -2
Day 0
Day 1 – Day 7
Day 8 – Day 14
Day 15 – Day 21
Day 22- Day 28
Day 28 ( 4 days)BB
Month 2 ( 2 weeks)S
Months 3 ( 2 weeks)
Month 6 ( 2 months)
Month 12 ( 3 months)
Month 18 and 24
( 6 months)
Yearly ( 6 months)
-HCG or urine 
pregnancy testE
X
XF
PT/PTT
X
XH
XO
XO
XO
X
D-dimer, Fibrinogen
XH
XO
XO
XO
X
Complement studies 
(C3/C4 and Total 
complement or CH50)
XH
XP
XP
X
Soluble IL2R
XH
XP
XP
X
ChemistriesI
X
X
XX
XG
XG
XG
XG
X
X
X
X
X
X
X
Immunoglobulins
X
CBC w/diff & platelets
X
X
XX
XG
XG
XG
XG
X
X
X
X
X
X
X
TBNK or PID panelAA
X
XH
XY
XY
XY
XZ
XZ
XZ
XZ
Urinalysis
X
X
X
X
X
Optional hematology 
studies
XQ
XQ
XQ
Imaging Studies
XJ
XJ
XJ
XJ
XJ
XJ
XJ
Bone marrow to include 
flow cytometry (bone 
X
XK
X
X
X
X
X

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Pre-Cell 
Infusion
Lymphodepleting 
Chemotherapy
CAR 
Infusion
Post CAR (Days 1-28)
Post CAR Follow-up
(Month 2 and beyond)
PROCEDURE
ScreeningA
BaselineB
Day -5
Day -4
Day -3
Day -2
Day 0
Day 1 – Day 7
Day 8 – Day 14
Day 15 – Day 21
Day 22- Day 28
Day 28 ( 4 days)BB
Month 2 ( 2 weeks)S
Months 3 ( 2 weeks)
Month 6 ( 2 months)
Month 12 ( 3 months)
Month 18 and 24
( 6 months)
Yearly ( 6 months)
marrow  biopsy as 
feasible)
Lumbar puncture for 
cell count, cytospin 
and/or flow cytometry 
(as feasible)
XT
XL
XL
XL
XL
XL
X
L
Peripheral blood flow 
cytometry
X
XH
XO
XO
XO
X
X
X
X
X
X
Research samplingM
X
X
X
X
X
X
X
X
X
X
X
X
Apheresis
XU
Fludarabine
X
W
X
X
X
Cyclophosphamide
X
W
X
Pentostatin
Xw
, CC
XCC
Mesna
X
W
X
Anti-CD19/anti-CD22 
CAR transduced cells
X
Levetiracetam (Keppra)
XN

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Pre-Cell 
Infusion
Lymphodepleting 
Chemotherapy
CAR 
Infusion
Post CAR (Days 1-28)
Post CAR Follow-up
(Month 2 and beyond)
PROCEDURE
ScreeningA
BaselineB
Day -5
Day -4
Day -3
Day -2
Day 0
Day 1 – Day 7
Day 8 – Day 14
Day 15 – Day 21
Day 22- Day 28
Day 28 ( 4 days)BB
Month 2 ( 2 weeks)S
Months 3 ( 2 weeks)
Month 6 ( 2 months)
Month 12 ( 3 months)
Month 18 and 24
( 6 months)
Yearly ( 6 months)
Adverse Events 
(Toxicity assessments)
X
X
X
X
X
X
X
X
X
X
X
X
Concomitant 
Medications
X
X
X
X
X
X
A. Within 4 weeks of treatment consent unless otherwise specified
B. Within 3 days of beginning preparative regimen unless otherwise specified
C. As per section 3.10.5, and then routinely (every 4 hours) unless otherwise clinically indicated
D. If clinically indicated
E.
All IOCBP 
F.
All IOCBP, within 3 days of beginning lymphodepleting chemotherapy
G. At least twice weekly through Day 28
H. Within 14 days of treatment
I.
Sodium (Na), Potassium (K), Chloride (Cl), Total CO2 (bicarbonate), Creatinine, Glucose, Urea nitrogen (BUN), Albumin, Calcium total (Ca), 
Magnesium total (Mg), Inorganic phosphorus, Alkaline phosphatase, ALT/GPT, AST/GOT, Bilirubin total and direct, LDH, CRP, uric acid, 
ferritin, triglycerides, total protein.
J.
Scans:  Appropriate imaging methods of any sites relevant to the subject’s disease (e.g. CT Scan, PET/CT, MRI)
K. In participants where there is no evidence for cytokine release syndrome or CAR-T cell expansion and early confirmation of disease progression 
would be clinically relevant, an early bone marrow evaluation may be performed Day +21 (± 4 days).
L.
In participants with a history of CNS involvement, an LP for cell count, cytology,  flow cytometry will be done. See section 4.1.3.1. Further, 
intrathecal therapy will NOT be administered in any participant who develops neurologic toxicity until at least 2 weeks after complete resolution 
(exception:  intrathecal hydrocortisone may be administered as indicated for treatment of severe neurotoxicity or intrathecal chemotherapy may 
be administered for progressive leukemia.
M. See Appendix I

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N. Participants will start prior to CAR T-cell infusion, per PI discretion. Alternative seizure prophylaxis may be used as clinically indicated. This 
may be stopped as clinically indicated post CAR T-cell therapy
O. At least once a week through Day 28
P.
On Day 10 and Day 21 (both 4 days)
Q. Optional hematology studies to be performed weekly on Days 7-21 ( 3 days) only as feasible in those with evidence of clinically significant 
DIC. See section 5.1.
R. Participants will be followed clinically until toxicity resolves to < grade 1 or baseline regardless of disease status.
S.
The 2-month follow-up will be done as feasible.
T.
Within 30 days prior to enrollment onto treatment protocol
U. To be performed any time prior to day -7
V. Within 4 weeks of apheresis If apheresis has already been performed on another protocol, this testing will not be required.
W. Intensified Lymphodepletion only
X. Within 1 day of cell infusion
Y. Day 14, 21, 28 (± 4 days)
Z.
If feasible:  Monthly (± 2 weeks) for 2 months, then q3-6 months (± 1 month) until 1yr or CAR loss.
AA.Peripheral CD3 count may be calculated using flow cytometry results
BB. Studies performed within the last 4 days do not need to be repeated
CC. Pentostatin will be used if fludarabine is not available due to a national fludarabine drug shortage. 

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15.2.2 Appendix B 2:  Neurotoxicity Assessments Calendar
A. Within 30 days prior to starting preparative regimen
B. Only applicable in participants who remain on treatment and return for a 3-month post-infusion follow-up evaluation.
C. As clinically indicated.
D. See Appendix G
E. Brief battery of cognitive test evaluating memory, attention, processing speed, and executive functions. This battery of tests 
will only be applicable to those participants/parents who speak English or Spanish. 
F. As feasible.
G. Neurocognitive assessments and neurosymptom checklists will only be performed in participants with isolated CNS disease.
Assessment
BaselineA
Start of 
CRS        
(±2 days)
Peak of 
CRSF
Day +10
(± 4 days)
End of 
CRS        
(±1 week)
Day +28
(± 7 days)
3 monthsB
(± 1 month)
MRI/CT BrainC
X
NeuroSymptom 
ChecklistD,G
X
X
X
X
Neurocognitive Exam 
BatteryD, E, G
X
X
X
Neurology ExamD,
X
X
Handwriting SampleC
X
X
X
X
ICE score (≥ 12 years old)
X
X
X
CAPD score (< 12 years 
old)
X
X
X
ICANS grade
X
X
X

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15.3 APPENDIX C: GRADING OF ACUTE GVHD
Skin
Liver
GI Tract
Upper GI
Stage
Rash
Bilirubin
Diarrhea (ml/day)
0
No Rash
< 2 mg/dl
< 500 (<10/kg)
1
<25%
2.1-3.0 mg/dl
501-1,000 (10-15/kg)
Severe nausea/vomiting
2
25-50%
3.1-6.0 mg/dl
1,001-1,500 (15-20/kg)
3
>50%
6.1-15 mg/dl
>1,501 (20/kg)
4
desquamation
>15 mg/dl
Severe pain, ileus
Glucksberg Grade*
1
1-2
0
0
2
1-3
1
1
2o
0
1
1
2s
4
0
0
3
2-4
2-4 &/or
2-4 (1 only >2)
4
3-4
2-4
2-4
IBMTR Severity Index*
A
1
0
0
B
2
or
1-2
or
1-2
or
1
C
3
or
3
or
3
D
4
or
4
or
4
* Assigned based on highest score
Adapted from Rowlings PA et al: IBMTR Severity Index for grading acute graft-versus-host 
disease: retrospective comparison with Glucksberg grade. Br J Haematol 97:855,1997; Weisdorf 
DJ et al: Acute upper gastrointestinal graft-versus-host disease: clinical significance and 
response to immunosuppressive therapy. Blood 76:624, 1990.

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15.4 APPENDIX D: GUIDELINES FOR GRADING AND MANAGEMENT OF SUSPECTED CYTOKINE 
RELEASE SYNDROME
Cytokine Release Syndrome (CRS): Administration of CAR T cell immunotherapy is often 
complicated by significant acute toxicities in the first 1-3 weeks after T cell infusion. In many 
cases, clinical toxicities correlate with elevated inflammatory serum cytokine levels. The signs and 
symptoms most often experienced by participants receiving infusions of CAR T cells include, but 
are not limited to, tumor lysis syndrome, fever, fatigue, hypotension, tachycardia, acute renal 
failure, and neurological toxicities such as aphasia, ataxia, headache, somnolence, and coma. Fever 
is usually the first toxicity to occur.
The protocol PI or their designees will be notified with the onset of CRS and with any change 
in grade in CRS.
CRS Grading: Grading will be based on the 2019 ASTCT CRS Consensus Guidelines (Table 2:  
CRS Grading as per ASTCT Consensus Guidelines with Generalized Management Approach)(54, 
114); with more specific guidelines provided in Table 3.
Table 2:  CRS Grading as per ASTCT Consensus Guidelines with Generalized 
Management Approach
CRS parameter
Grade 1
Grade 2
Grade 3
Grade 4^
Fever
> 38
> 38
> 38
> 38
With EITHER
Hypotension
None
Not requiring 
vasopressors
Requiring a vasopressor 
with or without 
vasopressin
Requiring multiple 
vasopressors (excluding 
vasopressin)
And/or
Hypoxia
None
Requiring low-flow 
nasal cannula‡ or blow-
by
Requiring high-flow 
nasal cannula‡, 
facemask, 
nonrebreather mask, or 
Venturi mask
Requiring positive 
pressure (eg, CPAP, 
BiPAP, intubation and 
mechanical ventilation)
⁎Fever is defined as temperature ≥38°C not attributable to any other cause. In participants who have CRS then receive 
antipyretics or anticytokine therapy such as tocilizumab or steroids, fever is no longer required to grade subsequent CRS 
severity. In this case, CRS grading is driven by hypotension and/or hypoxia.
†CRS grade is determined by the more severe event: hypotension or hypoxia not attributable to any other cause. For example, 
a participant with temperature of 39.5°C, hypotension requiring 1 vasopressor, and hypoxia requiring low-flow nasal cannula 
is classified as grade 3 CRS. ‡Low-flow nasal cannula is defined as oxygen delivered at ≤6 L/minute. Low flow also includes 
blow-by oxygen delivery, sometimes used in pediatrics. High-flow nasal cannula is defined as oxygen delivered at >6 
L/minute. ^Intubation may be indicated in participants who have a degree of neurotoxicity where there is concern for their 
ability to maintain a patent airway. This may occur either in the setting of CRS or after CRS has resolved. The decision for 
intubation should not be captured as a grade 4 CRS when the other criteria for such are not met.  Intubation of a participant 
without hypoxia for the possible neurologic compromise of a patent airway alone or for a procedure is not, by definition, 
grade 4 CRS. 
**The definition of “High dose” vasopressors requires > 3 hours of any of the following: norepinephrine monotherapy > 20 
mcg/kg/min; dopamine monotherapy > 10 mcg/kg/min; phenylephrine monotherapy > 200 mcg/kg/min; epinephrine 

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Treatment Guidelines: These guidelines aim to prevent grade 3 CRS in participants treated with 
CD19/22CART with exception of allowance of low-dose pressor support, which may be used to 
prevent excessive fluid bolus administration and volume overload, which can exacerbate 
pulmonary edema in the setting of capillary leak.  
These guidelines may require modification based on each participant’s specific clinical 
circumstances. Failure to follow these guidelines exactly is not considered a protocol deviation. 
Treatment will be based on optimal medical management and does not necessarily correlate with 
CRS grade. 
**The impact of tocilizumab, siltuximab, and/or steroids or other immunosuppressive agents 
have not been studied in this protocol, utilizing this CAR construct for this participant 
population. Thus, the indication for use of tocilizumab, siltuxuimab, or other interventions for 
CRS will be made by the PI or their designee after discussion with the clinical care team and 
assessment of participant status.**
As of Amendment 5/08/2023, we will prioritize using siltuximab as first line CRS therapy for 
participants who require treatment for CRS see Figure 9. 
Table 3: Guidelines for Monitoring and Treatment of CRS
Symptom related to CRS
Suggested Intervention
General 
Management
•
Daily participant weight assessment
Vital Sign 
Monitoring
•
Vital signs (temperature, blood 
pressure, heart rate, respiratory rate, 
pulse oximetry) should be checked a 
minimum of every 4 hours during CRS
•
Strict I/Os q shift
Laboratory 
Monitoring
•
With first onset of fevers, initiate twice 
daily: CBC, acute care, mineral and 
hepatic panel, and once daily: 
PT/PTT/fibrinogen/d-dimer, ferritin, 
LDH, and CRP and others as clinically 
indicated (e.g., CPK) or per protocol
Infectious Disease 
Monitoring
•
Consider an infectious disease consult 
for all participants with a history of 
multi-drug resistant organisms or 
complex prior infectious disease history 
(prior to CAR infusion)
•
Expectant management for fever & 
neutropenia with antibiotic coverage
•
Imaging as clinically indicated
Electrolyte 
Abnormalities
•
Allopurinol for prevention of 
hyperuricemia associated with tumor 
lysis (as clinically indicated)
•
Electrolyte abnormalities are common, 
particularly hypoMg/Ca/Phos, and 
should be recognized and treated
monotherapy > 10 mcg/kg/min; if on vasopressin: vasopressin + norepinephrine equivalent of > 10 mcg/kg/min; and if on 
combination vasopressors (excluding vasopressin) >  norepinephrine equivalent (cumulative) > 20 mcg/kg/min

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Fever of ≥ 38 °C
•
Acetaminophen PO/IV every 4-6 hours, 
supportive care (avoid NSAIDS and 
steroids)
Persistent fever of ≥ 39°C for < 36 
hours that is unresponsive to 
acetaminophen
•
Optimize supportive care
•
See Figure 9 
Fever management
Persistent fevers ≥ 39°C for ≥ 36-48 
hours
•
See Figure 9
Initial hypotension
•
10-20 cc/kg or 500-1000 cc Fluid bolus, 
target Hgb > 8.0 g/dL, 
•
Echocardiogram as feasible and  as 
clinically indicated
•
Notify the ICU 
Persistent/recurrent hypotension after 
initial fluid boluses (within 6 hours)
•
Consider initiation of low-dose pressors  
for persistent hypotension after 1-2 fluid 
boluses. 
•
See Figure 9
•
Fluid balance must be closely 
monitored to avoid fluid overload while 
optimizing circulatory status; aggressive 
fluid boluses may precipitate respiratory 
compromise 
Hypotension
Worsening hypotension
•
Initiation of higher dose pressors or 
addition of a second pressor for 
hypotension (excluding vasopressin)
•
See Figure 9 
Requirements of any oxygen 
supplementation 
•
CXR (additional imaging as clinically 
indicated)
•
Assess fluid status
Signs of respiratory distress
•
CXR (additional imaging as clinically 
indicated)
•
Notify the ICU
•
See Figure 9
Oxygen 
Requirement
Increasing respiratory support with 
concern for impending intubation
•
STAT CXR (CT as clinically indicated)
•
Notify the ICU
•
See Figure 9
Consider ICU 
Transfer
•
Persistent hypotension with initiation of 
a second fluid bolus
•
Persistent tachycardia with a heart rate 
higher than 125 beats per minutes on at 
least 2 occasions separated by 4 hours 
(for > age 16 years) or > 150 beats per 
minute for age < 16 years
•
Ejection fraction abnormalities (>grade 
3)
•
Worsening respiratory status
•
Neurotoxicity necessitating ICU level 
care (e.g., 1:1 nursing, seizures, frequent 
neurological checks)

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Refractory CRS
Refractory or ongoing symptoms 24-48 
hours after 2 doses of Siltuximab
See Figure 9
Recurrent CRS
Recurrent symptoms within 24-48hrs 
after initial siltuximab 
•
See Figure 9 
DIC
Laboratory abnormalities, petechiae, 
nose bleeds, hematuria
•
Cryoprecipitate to maintain Fibrinogen > 
150 units
•
Platelet transfusions to maintain platelet 
count > 50,000/uL (or higher if 
suspected acquired platelet function 
defect)
•
PRBC 
transfusion 
to 
maintain 
hematocrit > 25
•
FFP to target PTT < 40 (as feasible)
•
Vitamin K to target INR < 1.3
Symptomatic*: presence of Ferritin > 
10,000 mcg/L and at least two of the 
following criteria: LFTs > grade 3, 
Creatinine > grade 3, Pulmonary 
edema > grade 3, presence of 
hemophagocytosis
•
Supportive care, optimize medical 
management. 
•
Consider Methylprednisolone 1-2 
mg/kg IV/PO up to every 6-12 hours 
with continued symptoms (First dose 2 
mg/kg). Wean with clinical 
improvement. 
•
Consider HLH dosing of 
dexamethasone 10 mg/m2/day for 
starting dose (or methylprednisolone 
equivalents for older subjects) Consider 
Anakinra (dosing based on 
rheumatology consult) but may consider 
starting at 5mg/kg/day divided BID to 
QID.
•
Rheumatology consult
HLH/MAS
Asymptomatic: laboratory-based 
findings alone without clinical 
manifestations
•
Supportive care, optimize medical 
management 
•
Consider Anakinra (dosing based on 
rheumatology consult).
Neurotoxicity 
Somnolence, seizure, blurry vision, 
hallucinations
•
Neuro consult
•
See separate guidelines listed below
*HLH will be suspected by the presence of Ferritin > 100,000 mcg/L and at least one of the following 
criteria: LFTs > grade 3, Creatinine > grade 3, Pulmonary edema > grade 3, presence of 
hemophagocytosis (115). 
Medication Maximum Dosing:
**Steroid dosing: For participants above 70 kg or with obesity, consider maximum daily steroid dose no greater 
than 150 mg methylprednisolone equivalents (e.g., 30 mg dexamethasone/day). 
•
Tocilizumab: Maximum dose of 800 mg/dose

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Figure 9
 

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15.5 APPENDIX E: CALCULATION OF WEIGHT FOR CELL DOSE CALCULATION IN MORBIDLY 
OBESE PARTICIPANTS
Formulation for deriving the weight to be used in targeting cell doses in morbidly obese 
participants.
1. Definition Obesity is defined as a BMI > 30. For the purposes of this protocol, dose 
adjustments using practical body weight will be considered for those who have class 2 
obesity or a BMI >35. Dose cap will be implemented at 100kg, even if participants do not 
meet class 2 obesity definitions.
BMI = wgt (kg) / [hgt (M)]2 
2. Calculation of ideal body weight is performed using the standard, published formula: 
Ideal body weight (IBW)
Definitions
IBW (adult male, age >20) 
50 kg + 2.3 kg per inch over 5 feet 
IBW (adult female), age >20) 
45.5 kg + 2.3 kg per inch over 5 feet 
IBW (pediatrics, age 2-20) 
50th percentile weight based on CDC growth curves 
3. Calculation of the “practical weight.” 
Calculate the midway point, halfway between the actual and ideal body weights (ie the 
average of the two numbers). This is the "practical weight" that may be used in calculating 
the targeted cell dose for participants who have a BMI >35. 
4. Example:
Participant’s actual weight = 120 kg. 
Participant’ s actual height 173 cm = 69 in
BMI = 40
IBW formula = 50 + 2.3(9) = 70.7 kg
Midway point between 70.0 and 120 = 95 kg.
The weight we would use in targeting cell dose is 95 kg. 
1 dose by weight with adjustment: 
•
IBW + 50%(Weight-IBW)
•
Practical body weight = (IDW + actual BW)/2
2 Formula
IBW (male participants) 
➢52 kg + 1.9 kg/inch above 5 feet
➢50 kg + 2.39 (height in inches – 60)
IBW (female participants)
•
49 kg + 1.7 kg/inch above 5 feet
➢45.5 kg + 2.39 (height in inches – 60)

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15.6 APPENDIX F: RESPONSE CRITERIA
For the purposes of this study, participants should be re-evaluated for response as outlined in 
section 6.3. 
15.6.1 Appendix F 1: Response for Lymphoma
In addition to a baseline scan, confirmatory scans should also be obtained at least 4 weeks 
following initial documentation of objective response.
Response Criteria Lymphoma (Adapted from: Cheson BD, et al., Recommendations for Initial 
Evaluation, Staging, and Response Assessment of Hodgkin and Non-Hodgkin Lyphoma.  J Clin 
Oncol 32:3059-3067. 

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Response Criteria for ALL
*Modified from: Cheson BD, et al. Revised recommendations of the International Working 
Group for diagnosis, standardization of response criteria, treatment outcomes, and reporting 
standards for therapeutic trials in acute myeloid leukemia. J Clin Oncol 2003;21:4642-4649
Bone Marrow Classification
% blasts (at least 200 cells counted)
M1
<5%
M2
5 - 25%
M3
> 25%
➢Complete Response (CR)
1. M1 marrow, absence of peripheral blasts (morphologic), absence of 
extramedullary sites of disease, peripheral blood neutrophil count > 1,000/L 
and platelet count > 100,000/L. This parameter will be the requisite criterion 
for CR. The following additional parameters will be reported as exploratory 
findings.
2. Morphologic CR with incomplete blood count recovery (CRi): Above CR 
criteria without specified blood counts.
3. Cytogenetic CR (CRcyto): In addition to above CR criteria, reversion to normal 
karyotype for those with previously detected cytogenetic abnormality.
4.
Molecular CR (CRmolec): In addition to above CRc criteria, normalization of 
previously detected molecular cytogenetic abnormality.
➢Partial Response (PR)
1.
M2 marrow and a decrease in the percentage of marrow blasts by at least 
50%, absence of peripheral blasts (morphologic), absence of extramedullary 
sites of disease.
➢Hematological Activity (HA)
Does not meet the criteria for CR or PR with any of the following:
1.
At least a 50% decrease in the percentage of marrow blasts 
2.
At least a 50% decrease in the absolute peripheral blast count 
3.
Improvement of the peripheral blood neutrophil count to > 1,000/L or 
platelet count to > 100,000/L
➢Stable Disease (SD)
1. Does not meet the criteria for CR, PR, HA, or PD

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➢Progressive Disease (PD)
1. Worse marrow classification (i.e., M status) with at least a 50% increase in the 
percentage of marrow blasts.
Or
2. No change in marrow classification (i.e., M status), but a 50% or greater 
increase in absolute peripheral blast count or extent of extramedullary disease
➢CNS Classification
CNS is the most common site of extramedullary disease in ALL. The following table lists the 
CNS disease classification. This classification should be used when evaluating the participant’s 
overall response to treatment.
CNS Classification
*Steinherz/Bleyer algorithm method of evaluating traumatic lumbar punctures:
If the participant has leukemic cells in the peripheral blood and the lumbar puncture is traumatic 
and contains ≥ 5 WBC/µL and blasts, the following algorithm should be used to distinguish 
between CNS2 and CNS3 disease:
CSF WBC/RBC > 2X Blood WBC/RBC
CSF Cell Count and Cytology
CNS 1
0 blasts on cytospin
CNS 2
< 5/µl WBCs, cytospin positive for blasts
or
Traumatic spinal tap with ≥ 10/µL RBCs, 
WBC ≥ 5/µL, cytospin positive for blasts but 
negative by Steinherz/Bleyer algorithm
CNS 3
≥ 5/µl WBCs, cytospin positive for blasts
or 
Traumatic spinal tap with ≥ 10/µL RBCs, 
cytospin positive for blasts, and positive 
Steinherz/Bleyer algorithm*

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15.7 APPENDIX G:  GUIDELINES FOR EVALUATION, GRADING AND TREATMENT OF CAR-T 
RELATED NEUROTOXICITY
15.7.1 Appendix G 1:  Encephalopathy assessment tools for grading of Immune effector Cell-
Associated Neurotoxicity Syndrome (ICANS)
To determine the ICANS grade, complete the appropriate encephalopathy assessment below:
1. Immune effector Cell-associated Encephalopathy (ICE) 
*For use with adolescents and adults ≥12 years of age.
Field
Suggested Assessment
Points
Orientation
Orientation to year, month, city, hospital
4 points
Naming
Name 3 objects (e.g., point to clock, pen, 
button)
3 points
Following Commands
E.g. show me 2 fingers or close your eyes and 
stick out your tongue
1 point
Writing
Ability to write a standard sentence (e.g. It is a 
sunny day)
1 point
Attention
Count backwards from 100 by 10
1 point
Score
ICANS Grade
10
No Impairment
7-9
Grade 1 ICANS
3-6
Grade 2 ICANS
0-2
Grade 3 ICANS
Participant unarousable and unable to perform 
ICE
Grade 4 ICANS

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2. Cornell Assessment of Pediatric Delirium (CAPD) 
*For use with children <12 years of age.
Answer the following based on 
interaction with the child over 
the course of the shift
Never
4
Rarely
3
Sometimes
2
Often
1
Always
0
1. Does the child make eye 
contact with the caregiver?
2. Are the child’s actions 
purposeful?
3. Is the child aware of his/her 
surroundings?
4. Does the child communicate 
needs and wants?
Never
0
Rarely
1
Sometimes
2
Often
3
Always
4
5. Is the child restless?
6. Is the child inconsolable?
7. Is the child underactive – very 
little movement while awake?
8. Does it take the child a long 
time to respond to interactions?

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ASTCT Immune effector Cell-Associated Neurotoxicity Syndrome (ICANS) Consensus Grading
Neurotoxicity Domain
Grade 1
Grade 2
Grade 3
Grade 4
ICE Score*
(≥12 years)
7-9
3-6
0-2
Participant unarousable and unable 
to perform ICE
CAPD score 
(<12 years)
<9
<9
≥9
Unable to perform CAPD
Depressed level of 
consciousness†
Awakens 
spontaneously
Awakens to voice
Awakens only to tactile stimulus
Participant is unarousable or 
requires vigorous or repetitive 
tactile stimuli to arouse. Stupor or 
coma.
Seizure (any age)
N/A
N/A
Any clinical seizure focal or 
generalized that resolves rapidly; 
or non-convulsive seizures on 
EEG that resolve with 
intervention.
Life-threatening prolonged seizure 
(>5 min); or repetitive clinical or 
electrical seizures without return to 
baseline in between. 
Motor weakness‡ 
(any age)
N/A
N/A
N/A
Deep focal motor weakness such as 
hemiparesis or paraparesis.
Raised ICP/Cerebral 
Edema (any age)
N/A
N/A
Focal/local edema on 
neuroimaging§
Decerebrate or decorticate 
posturing; or cranial nerve VI palsy; 
or papilledema; or Cushing’s triad; 
or signs of diffuse cerebral edema 
on neuroimaging.
Note:  ICANS grade is determined by the most severe event (ICE or CAPD score, level of consciousness, seizure, motor findings, raised 
ICP/cerebral edema) not attributable to any other cause.
*A participant with an ICE score of 0 may be classified as grade 3 ICANS if awake with global aphasia, but a participant with an ICE score of 0 
may be classified as grade 4 ICANS if unarousable.
†Depressed level of consciousness should be attributable to no other cause (i.e., no sedating medications).
‡Tremors and myoclonus associated with immune effector cell therapies may be graded according to CTCAE v5.0, but they do not influence 
ICANS grading.
§Intracranial hemorrhage with or without associated edema is not considered a neurotoxicity feature and is excluded from ICANS grading. It may 
be graded according to CTCAE v5.0. 

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Neurotoxicity Treatment Guidelines (suggested guidelines only)
Neurotoxicity Treatment*
Grade 1:
-
Supportive care
Grade 2:
-
Neurology Consult 
-
Vigilant supportive care
-
Consider brain imaging with MRI 
-
Consider corticosteroids first (e.g., dexamethasone 10 mg IV q6hrs, methylprednisolone 1mg/kg BID)
Grade 3:
-
As above with Grade 2
-
Consider ICU transfer
-
Consider EEG and/or CSF evaluations as clinically indicated
-
Monitor with continuous cardiac telemetry and pulse oximetry
-
Consider IT dexamethasone or hydrocortisone. 
Grade 4:
-
As above with Grade 3
-
Consider corticosteroids (e.g., methylprednisolone 1g/day x 3 doses, followed by a rapid taper consisting of 250 
mg BID x 2 days, 125 mg BID x 2 days and then 60 mg BID x 2 days) 
*CRS should be treated as per the standard guidelines for treatment of systemic CRS, which may include utilization of tocilizumab, 
siltuximab, and/or steroids. Guidelines for treatment of neurotoxicity is intended to augment treatment of underlying systemic CRS or 
for additional treatment of neurotoxicity that extends beyond other systemic manifestations of CRS. Please note that signs and 
symptoms of neurotoxicity may be delayed from onset of initial signs of CRS and vigilant care is needed to identify and optimize 
treatment of neurotoxicity. 

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15.8 APPENDIX H: NEUROLOGIC AND COGNITIVE TESTING TOOLS
15.8.1 Appendix H 1: Neuropsychological Test Battery (CD19/CD22-CAR)
 Domains
Measure
Age range (yrs)
Time (min)
Pre-baseline practice session (<2 min each of the 6 tasks)
5.0 – adult
10
--------------------------------------------------------------------------------------------------------------------------
Baseline and Day 28 follow-up (±7 days) assessment:
Processing Speed
Cogstate Detection Task
5.0 - adult
   3 
Attention
Cogstate Identification Task
5.0 - adult
3
Working Memory
Cogstate One-Back Task
5.0 - adult
4
Visual Learning/Memory Cogstate One Card Learning
5.0 - adult   
6
Executive Function
Cogstate Groton Maze Task
5.0 – adult
7
PSI
Wechsler SS and Cancellation
Verbal Fluency
DKEFS FAS and McCarthy category
5.0 – adult
2
Neurologic
Neuro-Symptom Checklist
all
(2)
Symptoms
(parent/observer report)
Background
Background Information Form
all
(5)
Information
(parent/observer report or adult self-report)
• This full test battery (cognitive tests and Neuro-Symptom Checklist) listed above will be administered at 
baseline and Day 28 post-infusion (± 7 days) to subjects who have isolated CNS disease, and who speak 
English and Spanish. It also will be administered at 3-months post-infusion if the participant returns for a 
follow-up evaluation.  
• The Neuro-Symptom Checklist (NSC) also will be administered to a parent/observer at Day 10 (± 4 days) 
and then again between day 28 post-infusion (± 7 days) to assess for late-developing or resolving 
neurotoxicity only in subjects with isolated CNS disease.  The same parent/observer should complete the 
checklist at each required time point when possible.  If a parent/observer is not available at baseline or 
follow-up evaluation, the adult participant can complete the checklist at these time points, but a 
parent/observer should complete it at the Day 10 (± 4 days) time point if at all possible. An interpreter can 
be used to administer the NSC to subjects who do not speak English if needed.  
• We estimate that this test battery takes < 1 hour to administer.  It will take about 45 minutes to complete 
at baseline, which includes a 10-minute practice session of the Cogstate tasks for all participants prior to 
the baseline testing, and approximately 30-35 minutes for subsequent assessments, which do not include 
the practice tests.   The parent or other observer familiar with the parent will be asked to complete the 
Neuro-symptom checklist (1-2 minutes) and background form (5 minutes) while the participant is being 
tested but an adult participant can complete these forms if no parent/observer is available.  

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•  Some measures may not be administered if the participant does not appear to understand the task or 
becomes frustrated, is extremely fatigued, is ill (e.g., nauseous), or has physical (e.g., motor, vision) 
difficulties. This will not be considered a deviation.
CogState Computerized Test Battery (when available)
CogState is an approximately 20-minute computerizeda battery for children and adults ages 4 - 
90 years, which includes tasks tapping processing speed, attention and vigilance, learning and 
memory, working memory and executive functions (Maruff et al., 2009; Pietrzak et al., 2009).  
This measure was designed for repeated assessments over a short time period with virtually no 
practice effects in adults and children due to multiple forms (Falleti et al., 2006; Mollica et al., 
2005).  Age-based standard scores (mean = 100, SD 10) are computed for each task based on a 
normative sample of several hundred individuals.  CogState has strong construct validity, 
minimal practice effects, and good stability.  It was designed to be language independent in order 
to ensure the validity of the tests in a cross-cultural setting (e.g., Bangirana et al., 2009; Boivin et 
al., 2010; Cairney, Clough, Jaragba & Maruff, 2007; Dingwall & Cairney, 2010; Dingwall, 
Maruff, Frederisckon & Cairney, 2011; Lewis et al., 2010).  Further, CogState has been used in 
numerous pediatric, as well as adult, oncology clinical trials.  
Detection Task: This subtest of the CogState takes 2 minutes to administer and measures 
psychomotor function and processing speed.  It uses a well-validated simple reaction time 
paradigm using playing card stimuli.  In this task, the playing cards are all red and black 
jokers.  The subject is asked to press the Yes key as soon as the card in the center of the 
screen flips over.
Identification Task: This task takes 2 minutes to administer.  It is a measure of visual attention 
and uses a well-validated choice reaction time paradigm using playing card stimuli.  In this 
task, the playing cards are all either red or black jokers.  The subject is asked whether the 
card currently being presented in the center of the screen is red.  This subject responds by 
pressing the Yes key when the joker card is red and No when it is black.
One Back Task: The One Back Memory task takes approximately 2 minutes to administer and 
is a measure of working memory.  It uses a well-validated n-back paradigm using playing 
card stimuli.  In this task, the playing cards are identical to those found in a deck of playing 
cards with the exception of the joker.  The subject is asked whether the card currently being 
presented is the same as the one presented immediately previously.  The subject responds by 
pressing the Yes or No key.
One Card Learning Task: This task takes 5 minutes to administer. The One Card Learning task 
is a measure of visual recognition memory and uses a well-validated pattern separation 
paradigm using playing card stimuli to measure hippocampal functioning.  In this task, the 
playing cards are identical to those found in a deck of playing cards with the exception of the 
joker.  The subject is asked whether the card currently being presented in the center of the 
screen was seen previously in this task.  The subject responds by pressing the Yes or No key. 
Continuous Paired Associate Learning Task: The Continuous Paired Associate Learning task 
is a measure of visual associate memory, which takes approximately 5-7 minutes to 

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administer.  It uses a well-validated paired associate learning paradigm that assesses 
hippocampal-dependent learning and memory by asking the subject to learn the locations of a 
number of amoeba-like shapes on the computer screen.  This task consists of a single 
amoeboid shape displayed in the center of the screen surrounded by a number of blue-filled 
circles.  Beneath all but two of the blue-filled circles are amoeboid shapes, one of which 
matches the central display; the two remaining circles are distractors.  In the exposure phase 
of the task all of the to-be-remembered pattern-location associations are presented on the 
computer screen simultaneously.  After a five-second delay, a pattern is shown in the central 
location and this signals that the subject should touch the location in the periphery that 
contains the same pattern.  This process continues until the participant has acknowledged all 
of the pattern-location associations.  The learning phase begins with the same task display 
presented during the exposure phase except that now all of the peripheral locations are shown 
as filled circles.  One of the patterns presented in the exposure phase is presented in the 
center location.  With the presentation of this pattern, the subject is required to select the 
peripheral location where an identical pattern is hidden beneath the circle. This process 
continues until the correct location of each pattern is found.  Finding the correct location for 
all patterns in the set is defined as a learning trial.  There are six learning trials. The software 
records each move as an error or as a correct move.
Groton Maze Learning Test: The Groton Maze Learning task is a measure of problem solving 
and reasoning and takes approximately 5-7 minutes to administer.  It uses a well-validated 
maze-learning paradigm.  In this task, the subject is shown a 10 x 10 grid of boxes on a 
computer screen.  A 28-step pathway is hidden among these 100 possible locations.  Each 
box represents move locations, and the grid refers to the box array (i.e., 10 x 10).  Subjects 
are required to find the hidden pathway guided by four search rules.  These are: do not move 
diagonally, do not move more than one box (i.e., do not jump), do not move back on the 
pathway, and return to the last correct location after an error.  At each step only the most 
recently selected box is shown.  Feedback is given with visual and auditory cues (green 
check marks and red crosses) to indicate whether the selected box is correct or incorrect.  The 
head of path, or the last correct location, flashes with a green check when two errors are 
made in succession (failing to return errors). There are 20 well-matched alternate pathways 
available.  The software records each move as an error or a correct move.
*All CogState descriptions are provided courtesy of CogState
Neuro-symptom checklist
The Neuro-symptom checklist, which consists of neurologic symptoms previously observed in 
participants experiencing cytokine release syndrome, was developed specifically for studies 
assessing neurotoxicity of CAR T cell therapy.  It assesses the severity (mild, moderate, severe) 
and duration (<24 hours, 24-48 hours, and >48 hours) of symptoms, including fever, visual and 
auditory hallucinations, responsiveness to commands, disorientation, depressed mood, pain, and 
fatigue.  The caregiver of the participant is asked to complete the checklist based on their 
observations in the past two weeks; if the caregiver is not available, the adult participant can 
complete the checklist. If possible, the same person(s) should complete the checklist at each 
evaluation.

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Participant’s Name: _________________________
Date: ________________
Rater’s Name: __________________________
Protocol: _____________
(Please have the same rater at each evaluation if possible)
Neuro Symptom Checklist
(For parent/adult observer of participants 2.0 years and older)
For each item below, please check one box to describe the worst severity and one box to indicate 
the duration of each of these symptoms in the past week:
1) Visual 
hallucinations
No   Yes
If yes:
a) Severity:
 Mild
 Moderate
 Severe     
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
2) Auditory 
hallucinations
No   Yes
If yes:
a) Severity:
 Mild
 Moderate
 Severe 
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
3) Unresponsive 
to commands
No   Yes
If yes:
a) Severity:
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
4) Disorientation/
confusion
No   Yes
If yes:
a. Severity:
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours

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5) Depressed/sad 
mood
No   Yes
If yes:
a. Severity:
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
6) Distressed/upset 
mood 
No   Yes
If yes:
a. Severity:
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
7) Drowsiness/
Sleepiness
No   Yes
If yes:
a. Severity:
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
8) Difficulty 
speaking
No   Yes
If yes:
a. Severity:
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
9) Pain
No   Yes
If yes:
a. Severity:
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
10) Seizures  
No   Yes
If yes:
a. Severity: 
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours

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11) Blurred 
vision  
No   Yes
If yes:
Severity: 
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours
12) Other (please 
specify):
_______________
No   Yes
If yes:
Severity: 
 Mild
 Moderate
 Severe
b) Duration:
 < 24 hours
 24-48 hours
 >48 hours

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15.8.2 Appendix H 1:  CAR Neurotoxicity Screen Checklist 
This form serves as a general guideline, but is not required. 
Examiner:_____________________________
Date:_____________________________
____Baseline Evaluation
____Follow-Up Evaluation
I.
Mental status 
Yes
No
Is subject alert and oriented to time and place?
Is subject able to perform 3-step command?
Can subject name 3 objects?
Comments:
 
II.
Cranial Nerves
Gross examination of cranial nerves:
Yes
No
Is cranial nerve II intact?
Are cranial nerves III, IV, VI intact?
Is cranial nerve V intact?
Is cranial nerve VII intact?
Is cranial nerve VIII intact?
Is cranial nerve IX intact?

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Is cranial nerve X intact?
Is cranial nerve XI intact?
Is cranial nerve XII intact?
Does subject have papilledema?
Comments:
III.
Deep Tendon Reflexes 
Biceps
Triceps
Brachioradialis
Knee
Ankle 
Babinski
Right
Left
 
Comments:
 
IV.
Motor 
Deltoid
Biceps
Triceps
Wrist 
flexors
Wrist 
extensors
Finger 
flexors
Iliopsoas
Quadrice
ps
Ankle 
dorsiflexi
on
Ankle 
plantar
flexion
Great
Toe
extensio
n
Right
Left
Comments:

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V.
Sensory
Vibration
RUE
RLE
LUE
LLE
Does it affect ADLs
Decreased to ankle
Decreased to knee
Decreased in finger
Decreased to wrist
Comments:
Temperature
RUE
RLE
LUE
LLE
Does it affect ADLs
Decreased to ankle
Decreased to knee
Decreased in finger
Decreased to wrist
Comments: 
 
Pinprick
RUE
RLE
LUE
LLE
Does it affect ADLs
Decreased to ankle
Decreased to knee
Decreased in finger
Decreased to wrist
Comments: 

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VI.
Coordination and Gait
Yes
No
Is subject able to perform rapid alternating movements?
Is subject able to perform finger to nose testing?
Does subject have normal gait?
Does subject have normal heel and toe walking?
Comments: 
VII.
Primary team to consult the following service at the request of the examiner: 
Ophthalmology
Neurology
Tendon Reflex Grading Scale
Grade
Description
0
Absent
1+
hypoactive
2+
Normal
3+
Hyperactive without clonus
4+
Hyperactive with clonus
Grading for Muscle Strength
Grade
Description
0/5
No muscle movement
1/5
Visible muscle movement, but no movement at the join
2/5
Movement at the joint, but not against gravity
3/5
Movement against gravity, but not against added resistance
4/5
Movement against resistance, but less than normal

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VIII.
Handwriting Sample: To be performed if feasible depending on participant clinical 
condition and age
Baseline prior to chemotherapy:
Start of CRS +/-2 days: 
CRS peak +/-2 days as feasible: 
CRS resolution:

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15.9 APPENDIX I: BIOSPECIMEN COLLECTION SCHEDULE AND FORMS
15.9.1 Appendix I 1: Correlative Sample Schedule
(the order of the research studies listed below reflect the priority should blood volume for research purposes become limited) Day 0 is 
the day of cell infusion
Study
Test/Lab Location^
Sample Timepoints
Volume/type
Tube*
Notes
Cell Product Samples
p24 antigen + PERT 
Assay (product 
only)/
Indiana University
As per Center for 
Cellular Engineering 
(CCE)  SOP
Minimum of 5 x 105 
cells from the cellular 
product
In cryovial with 
1mL freezing media 
(90% AB serum, 
10% DMSO)
Frozen at -80 C
Samples will be stored in 
CCE/ Frederick repository 
and tested only if clinically 
indicated. 
If clinical indication for 
testing exists, samples will be 
shipped on dry ice priority 
overnight to: Lisa Duffy
Indiana University Vector 
Production Facility
980 W. Walnut St., R3-C668
Indianapolis, IN 46202
e-mail: ljwoods@iupui.edu
phone: 317-274-0323
RCL (replication 
competent 
retrovirus)
Rapid PCR analysis 
(product only)
Location: DTM
As per Center for 
Cellular Engineering 
(CCE)  SOP
6 x 106 cells from 
both CAR transduced 
cells AND 
untransduced control 
cells
Fresh in culture 
media in sterile tube
To be performed in 
DTM
Performed in CCE 
Results must be available 
prior to cell infusion
CD4/8 selected 
Cell Product
Storage for 
future research
Biospecimen 
Processing Core 
(BPC)
As per Center for 
Cellular Engineering 
(CCE) SOP
3 vials 2x107 CD4/8 
enriched cells
In cyrovials in 1mL 
freezing media each 
(90% AB serum, 
10% DMSO)
Frozen at -80º C
Received from CCE 
BPC

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Study
Test/Lab Location^
Sample Timepoints
Volume/type
Tube*
Notes
Cell product
Storage for 
future research
Biospecimen 
Processing Core 
(BPC)
As per Center for 
Cellular Engineering 
(CCE) SOP
Residual cells that 
remain following 
selection of the 
starting material 
which will not be 
used for CAR T-cell 
manufacturing (e.g., 
the unselected 
fraction (discard) of 
non-T cells)
In cryovials with in 
1mL freezing media 
each (90% AB 
serum, 10% DMSO)
Frozen at -80º C
Received from CCE 
BPC
Manufactured 
Cell product 
Storage for 
future research 
and regulatory 
studies 
Biospecimen 
Processing Core 
(BPC) or Leidos 
Biomedical 
Research
As per Center for 
Cellular Engineering 
(CCE)  SOP
Up to 10 vials 2x107 
or unused cellular 
product unusable for 
participant treatment
In cryovials in 1mL 
freezing media each 
(90% AB serum, 
10% DMSO)
Frozen at -80 C
Received from CCE 
Post Infusion Product: BPC 
Unused cellular product: 
Courier to NCI-Frederick 
repository 301-846-5893 to 
schedule pick-up
Participant Testing
Flow Cytometry:
Bone marrow
ALL panel including 
hematagones and/or 
CAR detection
Stetler-Stevenson 
Lab
10/3S240
301-402-1716
1. At screening (may 
be done at CLIA 
certified outside lab)
2. Day 28 (± 4 days)
3. All additional 
samples only as 
feasible:  Monthly 
(± 2 weeks) for 2 
months, then q3-6 
months (± 1 month) 
until 1yr or CAR 
loss.
3-5 mL marrow 
aspirate
Collect 3-5 mL bone 
marrow aspirate into 
heparinized syringe 
and 
IMMEDIATELY 
remove syringe, 
MIX well inverting 
5 or more times.
This test will only be done 
when a marrow aspirate is 
clinically indicated or 
required to monitor disease 
status
Schedule with lab in advance 
using Microsoft Outlook 
Calendar and order test in 
CRIS

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Study
Test/Lab Location^
Sample Timepoints
Volume/type
Tube*
Notes
Flow Cytometry:
Peripheral Blood
ALL panel including 
hematogones and/or 
CAR detection
Stetler-Stevenson 
Lab
10/3S240
1. Prior to chemo 
(within 14 days) if 
applicable to disease 
site. (may be done at 
CLIA certified 
outside lab). 
Samples obtained 
from screenin 
evaluation is 
acceptable if done 
within 14 days
2. Day 7, 14, 21, 28 
(± 4 days)
3. All additional 
samples only as 
feasible:  Monthly 
(± 2 weeks) for 2 
months, then q3-6 
months (± 1 month) 
until 1yr or CAR 
loss.
10-20 mL peripheral 
blood 
Sodium Heparin 
tube a room 
temperature
Schedule with lab in advance 
using Microsoft Outlook 
calendar and order test in 
CRIS.
Flow Cytometry:
CSF
Flow Cytometry for 
CAR T cells/ 
Stetler-Stevenson 
Lab
10/3S240
301-402-1716
1. At screening (if 
feasible).
2. Day 28 (± 4 days)
3. All additional 
samples only as 
feasible:  Monthly 
(± 2 weeks) for 2 
months, then q3-6     
months (± 1 month) 
until 1yr or CAR 
loss.
3-8 mL CSF
Spinal fluid 
collection tube 
delivered 
immediately to the 
lab 
Flow media 
available on 3 NE 
North Procedure 
Area.
Repeat CSF studies will be 
done in participants with a 
history of CNS involvement. 

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Study
Test/Lab Location^
Sample Timepoints
Volume/type
Tube*
Notes
RCL (replication 
competent 
retrovirus)
 
High-sensitivity 
PCR analysis 
(participant 
samples)/
Indiana University
Prior to cell infusion 
(up to 14 days prior)
3-6 mL/ peripheral 
blood 
Purple top (EDTA) 
or PAX DNA tube 
refrigerated at 4 C
Samples will be stored in 
CCE/ Frederick repository 
and tested only if clinically 
indicated. 
If clinical indication for 
testing exists, samples will be 
shipped on ice pack priority 
overnight to: 
Lisa Duffy, Indiana 
University Vector Production 
Facility, 980 W. Walnut St., 
R3-C668, Indianapolis, IN 
46202; e-mail: 
ljwoods@iupui.edu; phone: 
317-274-0323
DNA for CAR
Peripheral Blood
PCR for CAR 
promoter from T cell 
genomic DNA/
Leidos Biomedical 
Research
1. Prior to cell 
infusion (within 1 
day)
2. Day 1, 7, 14, 21, 
28 (± 4 days)
3. If feasible:  
Repeat monthly (± 2 
weeks) X 2 months, 
then q3-6 months (± 
1 month) until CAR 
negative.
5 mL peripheral 
blood
PAX DNA tube per 
sample at room 
temperature
Samples will be stored and 
batched
Courier to NCI-Frederick 
repository 301-846-5893 to 
schedule pick-up

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Abbreviated Title: CD19/CD22 T-cell in Peds
Version Date: November 19, 2024
Study
Test/Lab Location^
Sample Timepoints
Volume/type
Tube*
Notes
DNA for CAR
Bone Marrow
PCR for CAR 
promoter from T cell 
genomic DNA/
Leidos Biomedical 
Research
2. Day 28 (± 4 days)
3. If feasible:  
Repeat monthly (± 2 
weeks) X 2 months, 
then q3-6 months (± 
1 month) until CAR 
negative.
3-8 mL bone marrow
PAX DNA tube per 
sample at room 
temperature
Samples will be stored and 
batched
Courier to NCI-Frederick 
repository 301-846-5893 to 
schedule pick-up
Serum Cytokine 
Levels 
(including by 
not limited to 
IFN-γ, IL-2, IL-
7, and TNFα)
Multiplex cytokine 
panel
Leidos Biomedical 
Research
1. Prior to cell 
infusion (within 1 
day)
2. Day 1 and Day 3
3. Daily for days 5-
21 (only while 
inpatient). While 
outpatient, to be 
collected at least two 
times weekly.
4. Day 28 (± 4 
days).
5.Additional 
samples may be 
collected monthly (± 
2 weeks), then q3-6 
months (± 1 month) 
until 1 yr or CAR 
loss.
4 mL peripheral 
blood
For scheduled 
samples 4 ml Green 
Sodium heparin tube 
at room temperature.
Cytokines that are 
done on evenings 
and weekends will 
be spun per NCI 
Frederick SOP and 
sent frozen.
At any time for participants 
suspected of developing 
cytokine storm, additional 
samples will be collected, 
stored in the refrigerator sent 
ASAP for analysis
Courier to NCI-Frederick 
repository. Call 301-846-
5893 to schedule sample 
pick-up.

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Study
Test/Lab Location^
Sample Timepoints
Volume/type
Tube*
Notes
Lymphocyte 
Phenotyping 
Panel
Lymphocyte 
Phenotyping PID 
Panel or TBNK
NIH Clinical Lab
1. Prior to chemo 
(within 14 days). 
Samples obtained 
from screening 
evaluation is 
acceptable if done 
within 14 days.
2. Day 14, 28 (± 4 
days)
3. If feasible:  
Monthly (± 2 weeks) 
for 2 months, then 
q3-6 months (± 1 
month) until 1yr or 
CAR loss.
6 mL peripheral 
blood
Purple top tube
Schedule with clinical lab 
301-496-4879 and order test 
in CRIS.
Sequence based 
detection of 
MRD (optional)
Adaptive 
Biotechnologies 
Corporation
1. At time of 
screening 
2. Day 28 (± 4 
days). 
3. Month 2 and 3 (± 
2 weeks) if feasible 
and applicable
1X106 PBMC in 
pellets 
(cryopreserved)
Bone marrow or 
peripheral blood 
Samples will be stored in 
NCI-Frederick repository, 
call 301-846-5893 to 
schedule pick-up.
Batched samples will be 
shipped on dry ice to 
Adaptive Biotechnologies:
1551 Eastlake Ave E, Suite 
200
Seattle, WA  98102 
Cytogenetics 
(Cyto)
Department of 
Transfusion 
Medicine
As clinically 
indicated, at PI’s 
discretion.
3-5 ml of bone 
marrow 
Marrow: 0.5 ml 
preservative-free 
sodium heparin in 
capped syringe
Order in CRIS as “Other 
Mayo Lab” 

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Abbreviated Title: CD19/CD22 T-cell in Peds
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Study
Test/Lab Location^
Sample Timepoints
Volume/type
Tube*
Notes
Gut Microbiome 
(Optional)
Hourigan Lab 
(NIAID) Building 50, 
Rm 5512
Phone: 240-292-4552
See 
Appendix I 2: Gut 
Microbiome 
Sample Collection 
Timepoints (all 
will be considered 
optional)
Collect sample with 
any clinically relevant 
event or if subject 
does not stool within 
designated time 
windows
Sterile container
Stool samples will be handled 
using standard contact 
precautions and stored at -80C as 
soon as possible after collection.
Metabolomic 
Analysis 
(optional)
Peripheral Blood
Taylor Lab (POB)
CRC/1-3940
1.
At the time of 
apheresis 
2.
Prior to 
lymphodepletion 
Following CAR-T 
therapy: Day 0, 7, 14, 
21, 28 (+/- 3 days).
5-10 ml peripheral 
blood
Sodium heparin tube 
at room temperature
Metabolomic 
Analysis 
(optional)
Urine
Taylor Lab (POB)
CRC/1-3940
1.
At the time of 
apheresis 
2.
Prior to 
lymphodepletion
Following CAR-T 
therapy: Day 0, 7, 14, 
21, 28 (+/- 3 days).
5 ml urine
Sterile container
The samples must be kept in a 
fridge (4C) – on ice and 
processed as soon as possible 
(<1-2 h) after blood draw
^ The location of specimen processing or analysis may be adjusted with the permission of the PI or laboratory investigator.
 *  Please note that tubes and media may be substituted based on availability with the permission of the PI or laboratory investigator. 

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15.9.2 Appendix I 2: Gut Microbiome Sample Collection Timepoints (all will be considered optional)

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15.9.3 Appendix I 3: CD19/CD22 Expression for FACS for Samples to be sent to NCI: 
Shipment and Consent Process
Section A
Samples
CD 19/22 Expression for FACS Analysis for Samples to be sent to NCI: Sample 
Preparation 
•
For subjects with malignant cells in the peripheral blood: collect approximately 5 cc of blood 
in green-top (Sodium Heparin) tube.
•
For subjects with probable marrow involvement, but without malignant cells in the blood: 
approximately 3-5 cc of marrow, add 1 cc of heparin (1,000 μ/mL) to the syringe prior to 
aspirating the marrow, place in green-top (Sodium Heparin) tube.
•
Label the tube with subject's name, date of birth and draw date. Sample should also be 
labeled as “bone marrow” or “peripheral blood.”
__________________________________________________________________________
Section B
Preparation of shipment
1. Schedule in advance with NIH, NCI, POB. 
Include the following email addresses:
NCIPBLLBMT@mail.nih.gov
2. Send subject’s or parents’ contact information to the NIH, NCI, POB team so that the 
NIH team can obtain phone consent.
Include the following email addresses:
NCIPBLLBMT@mail.nih.gov
3. Obtain Consent signatures. 
4. Collect blood or bone marrow per the directions in Section A
5. Label the sample with:
a. subject's name
b. date of birth
c.
draw date.  
d. label as “bone marrow” or “peripheral blood”
•
Fax to 301-480-5157.
6. Prior flow cytometry report from diagnosis or relapse.
7. CBC results from the day the sample was obtained.
8. Package according to FedEx regulations for Diagnostic/Clinical Specimen shipment. 
a.
The samples should be kept at room temperature and should be shipped in 
containers without ice.  Do not use ice.  Do not refrigerate.

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b. Samples are best shipped on a Monday, Tuesday, or Wednesday. Do not send 
samples on Friday, Saturday, or the day preceding a holiday. Tests are not run on 
weekends or holidays.
9. Include in Package with the sample:
a.
Original signed and witnessed consent.
b. Prior flow cytometry report from diagnosis or relapse.
c.
CBC results from the day the sample was obtained.
10. Ship by Federal Express First Overnight (earliest next business day delivery) so that 
the sample is delivered by 10 am the next morning).
*Note:  Samples that arrive after 10 am may be cancelled by the NIH Flow Cytometry Lab due 
to poor viability. In that case the sample would be discarded. If the sample is viable, results may 
be delayed. 
Ship To: 
Attn: Robert Honec/ Flow Cytometry Lab
Laboratory of Pathology, CCR, NCI, NIH
10 Center Drive, Bldg 10, Room 3S240
Bethesda, MD 20892
Phone: 301-480-8074/8077

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15.10 APPENDIX J: SUGGESTED INFECTION PROPHYLAXIS GUIDELINES
These are suggested guidelines only (not mandated) and should be applied only after discussion 
with the protocol and modified as needed based on individual needs.
CD19/CD22 CAR T Cell Antimicrobial Prophylaxis
For ANC < 500 (afebrile)
 
Fever
**If concern for Zosyn/penicillin allergy consider Meropenum. If anaphylaxis to 
penicillin, consult allergy in advance and plan for aztreonam/vancomycin
After resolution of fever 
without an identified infectious 
source and ANC < 500
Discontinuation of 
Anti-bacterial prophylaxis
Levofloxacin
prophylaxis
Switch to IV Zosyn**
Stop Levofloxacin
Broaden coverage (i.e., mero) or 
add aminoglycoside
Resume Levofloxacin
Prophylaxis. 
Discontinue IV 
antibiotics
Discontinue levofloxacin prophylaxis when: 
1. ANC > 250 without active infection after CRS, or
2. Day 28 if patient is outpatient and well, and
3. Consider G-CSF starting at day 28 (or as clinically 
indicated) if ANC < 250
If stable
If concern for resistance or hemodynamic 
instability/other clinical concerns         

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Antibacterial Prophylaxis
1.) When ANC < 500, will initiate Levofloxacin prophylaxis
a.
>40KG, Dose 500 mg Q 24 hours
b. 20-40KG, 250-375 mg Q24 hours
c.
< 20KG, Dose 10mg/kg Q 24 hours
2.) If participant has fever on Levofloxacin
a.
Routine surveillance blood cultures
b. Change antibiotics to IV Zosyn (may be modified based on participant specific 
antimicrobial resistance or allergy)
i. Adult Dosing: 4.5g Q 6 hrs
ii. Pediatric Dosing (< 40 kg): 100 mg/kg of piperacillin component q6h
c.
Stop Levofloxacin
d. In the setting of penicillin/Zosyn allergy, start with IV Meropenum
i. Adult and pediatric dosing: 20 mg/kg Q 8, max dose of 1 gram Q 8 hrs
ii. If history of true anaphylaxis to Penicillins, please consider 
aztreonam/vancomycin and discuss with allergy consult in advance of 
starting meropenum. For such participants, implementation of 
levofloxacin prophylaxis will be discussed on a case by case basis.  
3.) In the setting of suspected resistance, hemodynamic instability or clinical exam findings
a.
Consider addition of an aminoglycoside or broadening coverage 
4.) When participant defervesces and is clinically stable without an active infection, and has 
ANC < 500
a.
Consider stopping IV antibiotics
b. Add prophylactic Levofloxacin
5.) Consider discontinuing Levofloxacin prophylaxis at Day 28 if participant is outpatient, 
well-appearing, and/or when ANC >250 AND participant is clinically stable without any 
evidence for ongoing inflammation or CRS. Continue Levofloxacin as clinically 
indicated if ANC<250 and trial a dose of filgrastim. 
Antifungal Prophylaxis
1.) Micafungin 
a.
>50 KG, Dose 50 mg IV daily
b. < 50 KG, Dose 1 mg/kg IV daily
2.) Posaconazole
a.
13 years and older: Delayed release tablets: Day 1: 300 mg tab BID, then 300 
mg daily 
b. <13 yo or less than 40 kg: Oral Suspension: 4 mg/kg/dose TID, >13 years old: 
max 200 mg TID
c.
<13 yo or 25- 40 kg: Delayed release tablets 200 mg Q12 followed by 200 mg 
day 

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Antiviral Prophylaxis
1.) HSV prophylaxis with Acyclovir/Valtrex if + HSV titers
a. Acyclovir: 20mg/kg PO BID (max dose 800 mg BID)
PCP Prophylaxis
1.) Bactrim  Pentamidine (300mg inhaled q month) prior to CAR T cell infusion
2.) For participants that cannot do inhaled pentamidine (e.g. younger participant): 
Pentamidine may be given at 4 mg/kg (max 300 mg) intravenously once a month.