Response Assessment to Pembrolizumab With Standard of Care Therapy in Glioblastoma Using Ferumoxytol Steady State Imaging- A Pilot Study
Phase: PHASE2
Conditions: Glioblastoma
Sponsor: OHSU Knight Cancer Institute

 
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SPONSOR: Oregon Health & Science University 
OHSU eIRB# 16046 
Version 11, IRB Approved 05/30/23. 
NCT#: NCT03347617 
 
TITLE: Response Assessment to Pembrolizumab with Standard of Care Therapy in 
Glioblastoma Using Ferumoxytol Steady State Imaging– A Pilot Study 
 
 
Principal Investigator: 
 
Leslie Muldoon, PhD 
Associate Professor 
Department of Neurology 
Oregon Health & Science University 
(503) 494-5626 
 
Co-Investigators: 
 
 
 
 
 
 
Guang Fan, MD, PhD 
Director of Clinical Flow Cytometry Laboratory 
Director of Hematopathology Fellowship Program 
Department of Pathology 
Oregon Health and Science University 
(503)-494-9439 
 
Biostatistician: 
 
 
Rongwei (Rochelle) Fu, PhD  
 
 
 
 
 
 
 
Professor of Biostatistics 
Department of Public Health and Preventive Medicine 
Oregon Health & Science University 
(503) 494-6069 
(503) 494-4981 (FAX) 
 
 
Data Management/ 
Study Coordinators:  
 
Lisa Muir, MPA, CCRP 

 
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Department of Neurology 
Oregon Health & Science University 
(503) 494-5626 
(503) 494-5627 (FAX) 
 
Amy Huddleston, MPA, CCRP 
Department of Neurology 
Oregon Health & Science University 
(503) 494-5626 
(503) 494-5627 (FAX) 
 
 

 
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TABLE OF CONTENTS 
1.0 
TRIAL SUMMARY.................................................................................................... 8 
2.0 
TRIAL DESIGN.......................................................................................................... 8 
2.1 
Trial schema: ......................................................................................................... 10 
3.0 
OBJECTIVES ........................................................................................................... 11 
3.1 
Primary Objective ................................................................................................. 11 
3.2 
Secondary Objectives: .......................................................................................... 11 
3.3 
Exploratory Objectives: ....................................................................................... 11 
3.4 
Hypotheses ............................................................................................................. 12 
4.0 
BACKGROUND & RATIONALE .......................................................................... 12 
4.1 
Trial Description ................................................................................................... 25 
4.2 
Pharmaceutical and Therapeutic Background .................................................. 25 
4.3 
Preclinical and Clinical Trial Data ...................................................................... 27 
4.3.1 Rationale for the Trial and Selected Subject Population .................................... 27 
4.3.2 Rationale for Dose Selection/Regimen/Modification ......................................... 28 
4.3.3 Preclinical studies ............................................................................................... 29 
4.3.4 Clinical Studies ................................................................................................... 30 
4.3.5 Pharmacokinetics and Drug Metabolism in Humans .......................................... 34 
4.3.6 Rationale for Endpoints ...................................................................................... 36 
5.0 
METHODOLOGY ................................................................................................... 37 
5.1 
Diagnosis/Condition for Entry into the Trial ..................................................... 37 
5.2 
Subject Inclusion Criteria .................................................................................... 37 
5.3 
Subject Exclusion Criteria ................................................................................... 38 
5.4 
Subject Withdrawal/Discontinuation Criteria ................................................... 39 

 
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5.4.1 Early stopping rule .............................................................................................. 40 
5.4.2 Discontinuation of Study Therapy after CR ....................................................... 40 
5.4.3 Subject Replacement Strategy ............................................................................ 41 
5.4.4 Clinical Criteria for Early Trial Termination ...................................................... 41 
6.0 
Schedule of Events .................................................................................................... 42 
7.0 
Treatment Plan and Procedures .............................................................................. 44 
7.1 
Participant Screening and Enrollment ............................................................... 44 
7.2 
Participant Registration ....................................................................................... 44 
7.3 
Trial Treatments ................................................................................................... 44 
7.4 
Study procedures narrative ................................................................................. 46 
7.5 
Informed Consent ................................................................................................. 47 
7.6 
Trial Procedures ................................................................................................... 48 
7.7 
Post-study anticancer therapy status .................................................................. 54 
7.8 
Safety Follow-Up Visit: 30 days post discontinuation ....................................... 54 
7.9 
Follow-up ............................................................................................................... 54 
7.10 
Survival Follow-up when off study...................................................................... 54 
7.11 
Second Course Phase (Retreatment Period) ...................................................... 55 
7.12 
Dose modification and toxicity management for immune-related AEs 
associated with pembrolizumab .......................................................................... 56 
7.13 
Dose Modifications for Ferumoxytol and Temozolomide ................................. 60 
7.14 
Trial Blinding/Masking ........................................................................................ 61 
7.15 
Randomization or Treatment Allocation ............................................................ 61 
7.16 
Stratification .......................................................................................................... 61 
7.17 
Concomitant Medications/Vaccinations (allowed & prohibited) ..................... 61 
7.17.1 Acceptable Concomitant Medications ................................................................ 61 
7.17.2 Prohibited Concomitant Medications and Therapies .......................................... 62 

 
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7.18 
Pharmacokinetic/Pharmacodynamic Evaluations ............................................. 63 
7.19 
Blood Collection for Anti-Pembrolizumab Antibodies ..................................... 63 
7.20 
Blinding/Unblinding ............................................................................................. 63 
7.21 
Diet/Activity/Other Considerations ..................................................................... 63 
7.22 
Contraception ........................................................................................................ 63 
7.23 
Use in Pregnancy ................................................................................................... 64 
7.24 
Use in Nursing Women ......................................................................................... 64 
8.0 
Response Assessment, Image processing and Biomarkers .................................... 64 
8.1 
Definitions for Response assessment: .................................................................. 64 
8.2 
Image processing ................................................................................................... 66 
8.2.1 For CNS lesions: ................................................................................................. 66 
8.2.2 For systemic lesions (only Arm 1). ..................................................................... 67 
8.3 
Tumor Tissue Collection and Correlative Blood Biomarker Studies .............. 68 
8.3.1 Blood Biomarkers ............................................................................................... 68 
8.3.2 Tissue Biomarkers .............................................................................................. 68 
9.0 
Adverse Events .......................................................................................................... 69 
9.1 
Adverse Event (AE) Monitoring .......................................................................... 69 
9.2 
Sponsor Responsibility for Reporting Adverse Events ..................................... 69 
9.3 
OHSU IRB Reporting of Unanticipated Problems and Adverse Events ......... 69 
9.4 
Assessing and Recording Adverse Events .......................................................... 69 
9.5 
Rescue Medications & Supportive Care ............................................................. 70 
9.5.1 Supportive Care Guidelines ................................................................................ 70 
9.5.2 Expected AEs from Ferumoxytol and Guidelines for Management ................... 71 
9.6 
Additional IND Reporting Requirements for Ferumoxytol ............................. 75 
9.6.1 Expected AEs from Temozolomide .................................................................... 75 

 
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9.6.2 Definition of an Overdose for This Protocol and Reporting of Overdose to the 
Sponsor and to Merck ......................................................................................... 78 
9.6.3 Reporting of Pregnancy and Lactation to the Sponsor and to Merck ................. 78 
9.6.4 Immediate Reporting of Adverse Events to the Sponsor and to Merck.............. 78 
9.6.5 Evaluating Adverse Events ................................................................................. 80 
10.0 
STATISTICAL ANALYSIS PLAN ........................................................................ 80 
11.0 
LABELING, PACKAGING, STORAGE AND RETURN OF CLINICAL 
SUPPLIES ................................................................................................................. 82 
12.0 
ADMINISTRATIVE AND REGULATORY DETAILS ....................................... 84 
12.1 
Retention of Records ............................................................................................ 84 
12.2 
Data Collection, Storage, Privacy, Confidentiality and Security ..................... 84 
12.3 
Data Storage and disposition ............................................................................... 85 
12.4 
Future Use of Stored Specimens .......................................................................... 86 
12.5 
OHSU Knight Cancer Institute Data and Safety Monitoring Plan .................. 86 
12.6 
Clinical Data & Safety Monitoring ..................................................................... 87 
12.7 
Quality Assurance & Quality Control ................................................................ 87 
13.0 
Ethics/Protection of Human Participants ............................................................... 88 
13.1 
Ethical Standard ................................................................................................... 88 
13.2 
Institutional Review Board .................................................................................. 88 
13.3 
Informed Consent ................................................................................................. 88 
13.4 
Protocol Review ..................................................................................................... 89 
13.5 
Changes to Protocol .............................................................................................. 89 
14.0 
Inclusion of Women, Minorities and Children in Clinical Trials ......................... 89 
15.0 
Supplemental Material ............................................................................................. 91 
15.1 
ECOG Performance Status .................................................................................. 91 
15.2 
Common Terminology Criteria for Adverse Events V4.0 (CTCAE) ............... 91 

 
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15.3 
Ferumoxytol Investigator’s Brochure ................................................................. 91 
15.4 
Pembrolizumab Package insert ........................................................................... 91 
15.5 
Temozolomide Package Insert ............................................................................. 92 
16.0 Appendices ..................................................................................................................... 92 
Appendix A: Ferumoxytol Adverse Events Form ......................................................... 92 
Appendix B: Pembrolizumab Adverse Events Form .................................................... 92 
17.0 References ...................................................................................................................... 93 
 
 
Version # 
OHSU IRB Approval Date 
Version 1 
initial submission 5/15/17 
Version 2 
Submitted to IRB 12/14/17; approved 1/11/18 
Version 3 
Submitted to IRB 5/24/18; approved 7/26/18 
Version 4 
Submitted to IRB 10/5/18; approved 11/29/18 
Version 5 
Submitted to IRB 5/3/19; approved 6/19/19 
Version 6 
Submitted to IRB 6/26/19; approved 7/11/19 
Version 7 
Submitted to IRB 12/31/19; approved 2/18/20 
Version 8 
Submitted to IRB 5/1/20; approved 6/30/20 
Version 9 
Submitted to IRB 1/26/21; approved 2/26/21 
Version 10 
Submitted to IRB 3/31/22; approved 04/01/22 
Version 11 
Submitted to IRB 05/22/23; approved 05/30/23 
 
 

 
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1.0 TRIAL SUMMARY 
Abbreviated Title 
Assessment Of Response To Pembrolizumab In Primary Brain 
Tumors Using Ferumoxytol Steady State Imaging– A Pilot 
Study. 
Trial Phase 
Pilot study, phase II 
Clinical Indication 
Metastatic  melanoma (closed after enrolling 2 subjects), 
glioblastoma 
Trial Type 
Single institution, multi-arm, phase II pilot study for safety 
and efficacy in conjunction with experimental imaging for 
disease response 
Type of control 
None  
Route of administration 
Intravenous pembrolizumab and intravenous ferumoxytol 
Trial Blinding 
None 
Treatment Groups 
Two arms; Arm 1: melanoma (closed after enrolling 2 
subjects); Arm 2: glioblastoma 
Number of trial subjects 
Total 45 (Glioblastoma: 43; Melanoma 2 (closed)) 
Estimated enrollment period 3 years 
Estimated Duration of Trial 
5 years 
Duration of Participation 
5 years 
 
 
 
 
2.0 TRIAL DESIGN 
This study will evaluate incidence, magnitude and timing of true vascular tumor progression, 
pseudoprogression and immune response to pembrolizumab in patients with primary brain 
tumors using ferumoxytol steady state MRI imaging.  
 
Originally, the study had two arms:  
 
ARM 1: Metastatic brain tumors - Metastatic melanoma  
ARM 2: Primary brain tumors - Glioblastoma (GBM) 
 
In December 2019, we decided to stop the enrollment to the melanoma arm and allocate the 
remaining 18 slots to the Glioblastoma arm – a total of 43 subjects will now be enrolled in the 
GBM arm.  
 
Treatment 
Subjects scheduled to receive standard of care stereotactic radiosurgery (SRS) for brain 
metastases in Arm 1 or standard of care chemoradiation (CRT) with temozolomide for GBM 
in Arm 2, are eligible. All subjects will receive pembrolizumab (200mg intravenous every 3 
weeks) in addition to standard of care SRS or CRT in the respective arms, until toxicity, or 
persistent radiographic progression is confirmed, whichever comes first.  
 
Imaging 
All subjects will be scanned with clinical MRI at baseline prior to radiation, 4 weeks after the 
last day of radiation and every 9 weeks thereafter until completion or until taken off-study for 

 
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progression or toxicity. Ferumoxytol MRI (FeMRI) will be performed in the same day and 
sitting as the clinical MRI at baseline and 4 weeks after the last day of radiation timepoints. 
FeMRI may be performed independently (on a different day or different MRI setting) of the 
clinical MRI if there is suspected radiographic progression or to confirm radiographic 
progression. If there is suspected progression, subjects undergo a ferumoxytol steady state MRI 
and continue on pembrolizumab for one more cycle. The decision regarding continuation of 
pembrolizumab will be made by the principle investigator based on clinical findings that 
include (1) stable ECOG performance status with no more than 8mg of dexamethasone (or 
equivalent) a day; (2) absence of new or worsening symptoms not managed with steroids; and 
(3) absence of progressive tumor at critical anatomical sites (e.g., spinal cord compression) 
requiring urgent alternative medical intervention. Follow up clinical standard of care and 
ferumoxytol MRIs will be repeated to confirm persistent radiographic progression in 4 weeks. 
During this 4 week follow up period, subjects will be followed with a clinical exam weekly to 
monitor for clinical stability. If the 4 week follow up scan confirms progression (as defined in 
section 8.1), then pembrolizumab is discontinued and subject is evaluated for clinical 
indication of standard of care surgery or biopsy. Surgery or biopsy is performed only if 1) the 
lesion is deemed easily accessible 2) surgery is not expected to worsen neurological outcomes 
and 3) it is in the best clinical interest of the subject. The decision regarding surgery will be 
consensus based and when possible, will be made after each individual case has been presented 
at the OHSU multi-disciplinary brain tumor board.  If histopathology confirms 
pseudoprogression or is inconclusive, the subject will continue on pembrolizumab every 3 
weeks until further radiographic progression is suspected. If histopathology confirms 
progression, the subject will be removed from the study. Subjects with evidence of new lesions 
distant from the primary lesion/s  (not present at entry to the study) in the CNS or systemically 
that fulfil criteria for progression by immune related response criteria (irRC)[1] will be taken 
off study drug, but will be followed with serial clinical standard of care MRI. 
 
An optional, additional third imaging session may be performed with no additional contrast 24 
hours after ferumoxytol administration. This optional day of imaging will be used to evaluate 
delayed ferumoxytol enhancement and will be performed in only those patients who have 
consented. 
 
Biomarker 
Optional blood for biomarker evaluation may be drawn as described in section 8.3.1. These 
markers will be correlated with imaging findings and survival. Analysis will be performed by 
the OHSU clinical flow cytometry laboratory. 
 
Any archival biopsy, fresh tissue, as well as tissue obtained at persistent radiographic 
progression will be obtained for clinical pathology review at OHSU. Tissue samples will be 
sent to QualTek Molecular Laboratories for PD-L1 biomarker assay as described in section 
8.3.2. 
 
For Group 1 only: In addition, subjects that are already enrolled in the study and have 
measurable systemic disease (outside the CNS) by RECIST 1.1 Criteria [2] at screening, may 
undergo optional additional MRI sequences of the systemic disease to evaluate the 
immunological response to pembrolizumab outside the CNS (systemic disease). 

 
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2.1 
Trial schema: 
 
 
 
 
 
 
 
 
 
 
Legend for study schema for arms 1 and 2:  
: Ferumoxytol steady state MRI 
CRT: Chemo-radiation therapy 
MRI: Magnetic resonance imaging 
PRP: Persistent radiographic progression 
SRP: Suspected radiographic progression 
SRS: Stereotactic radiation therapy 
TMZ: Temozolamide 

 
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Imaging schema: 
 
3.0 OBJECTIVES 
3.1 
Primary Objective 
Determine the sensitivity and specificity of relative cerebral blood volume (rCBV) 
measured by steady state MRI with ferumoxytol in identifying true vs pseudoprogression 
in patients with newly diagnosed GBM receiving pembrolizumab with standard of care 
chemo-radiation. 
 
3.2 
Secondary Objectives: 
1. Determine the safety and toxicity of pembrolizumab when used in combination with 
standard of care  chemo radiation. 
2. Determine the progression free survival (PFS), overall survival (OS), clinical response 
and duration of best response. 
 
Rationale: Given the relatively small sample size, we aim to collect preliminary data on 
safety and toxicity as well as progression free survival, overall survival, best response 
and duration of best response survival. Data from this pilot study will be used to power 
a larger study. 
 
3.3 
Exploratory Objectives: 
1. Compare the immune response as determined by the volume, pattern and intensity of 
delayed (24hr) ferumoxytol uptake between subjects who develop true vs 
pseudoprogression. This is optional and will be performed only in patients who have 
provided additional consent. 
 
2. Investigate the serum immunological parameters (serum biomarker) and correlate 
clinical as well as radiological response with systemic immune response to 
pembrolizumab as measured by immunological panel. 
 
 
Timeline of MRIs: subjects will be scanned at multiple stages of disease. Clinical and ferumoxytol MRIs will be 
performed on the same day in each time point except for the one when clinical MRI follow up reveals radiological 
progression. In that case ferumoxytol imaging alone will be performed shortly after the radiological diagnosis. Note 
that this study will include only short study MRI with ferumoxytol, which may be attached to clinical MRI. 
Pembrolizumab treatment will start at day 1 of radiation and continue till persistent radiological progression. 

 
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3. Compare the changes in PDL-1 expression in the biopsy tissue before and after therapy 
at the time of progression and correlate PD-L1 expression with response rates and 
survival. 
 
4. In subjects in metastatic arm with any measurable systemic lesions, investigate the 
feasibility of measuring vascular volume fraction (VVF), vessel size index (VSI) and 
vessel density index (VDI) as surrogate for response (true vs pseudoprogression, as 
determined by RECIST 1.1 and irRC [1, 2]. 
 
3.4 
Hypotheses 
Since this is a pilot study to determine feasibility of administration of ferumoxytol with 
pembrolizumab and imaging logistics, no formal hypothesis is being tested. We expect rCBV 
measurements using ferumoxytol steady state MRI will be able to accurately identify true vs 
pseudoprogression. Neovascularization is pivotal for tumor viability and high grade tumors are 
expected to have a higher vascularity and hence a higher blood volume. An immune response 
or pseudoprogression is expected to have low vascularity and hence a lower rCBV. Prior 
studies have shown that rCBV value greater than or equal to 1.75 indicated active tumor while 
rCBV below 1.75 suggest an inflammatory response [3, 4]. Approximately 24 -72 hours after 
intravenous injection, ferumoxytol is taken up by activated inflammatory cells including M1 
macrophages. An increased uptake on delayed scans suggests a robust inflammatory response 
and hence pseudoprogression and is seen as increased enhancement in T1 weighed images 
obtained 24 hours after Ferumoxytol injection. 
 
There will be evidence of up regulation of the immune system serum biomarker assay at 
various time points. Multicolor flow cytometry as described in section 8.3.1 will be used to 
evaluate various immune cell populations to correlate clinical and radiological response with 
systemic immune responses. 
 
PD-L1 testing will be performed by the CRO QualTek Molecular Laboratories.  Any archived 
tissue samples or tissue obtained from brain biopsy prior to enrollment (archival tissue) and 
those obtained at suspected radiographic progression will be sent to the CRO for PD-L1 
expression assay.  We will correlate outcomes and imaging findings with PD-L1 expression in 
archival systemic tumor tissue, brain biopsy prior to enrollment, and tissue obtained at 
persistent radiographic progression. Frozen tissue and fixed tissue blocks from initial lung 
biopsies will be used. In a subset frozen sections and fixed tissue blocks from subjects who 
undergo resection of brain metastases for clinical indications will also be utilized. Tissue 
obtained at initial surgery will be stained for PD-L1. We expect to see a linear correlation 
between tumor PD-L1 expression, immune infiltrate, and response rates and survival. 
 
 
 
 
 
4.0 BACKGROUND & RATIONALE 
Refer to the Investigator’s Brochure (IB)/approved labeling for detailed background 
information on pembrolizumab and ferumoxytol, and the product insert for temozolomide. 

 
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Introduction 
Immune checkpoints, particularly inhibitors of programmed cell death protein (PD-1), have 
emerged as important mechanisms for immunosuppression and immune-evasion in 
malignancies [5] . High PD-1ligand expression is seen in malignancies including melanoma, 
non-small cell lung carcinoma, triple-negative (ER, PR, and HER2 negative) breast cancer and 
glioblastoma multiforme (GBM). There is great enthusiasm in the neuro-oncology community 
to design trials to test pembrolizumab in primary and metastatic brain tumors [1, 6-11]. 
Unfortunately, most prior studies looking at systemic malignancies excluded brain metastases 
and hence there is limited data on its efficacy in this patient population. 
 
Immunotherapy for brain tumors: 
Prognosis for primary and metastatic brain tumors continues to be poor [12-14]. Current 
standard of care therapies includes surgery, radiation and cytotoxic chemotherapy. Over the 
last decade, targeted molecules and better radiation techniques have failed to deliver the 
paradigm improvement in progression free or overall survival rates seen with systemic cancers 
[15]. 
 
Challenges unique to brain tumors include drug delivery across the neurovascular unit (NVU), 
limiting neurotoxicity, and preserving quality of life. In addition, these tumors evade immune 
surveillance and dampen the anti-tumor immune response by down regulation of HLA 
molecules, expression of immunosuppressive cytokines, increasing the activation of T-
regulatory (Treg) cells, and increasing the T helper cell phenotype [16]. The brain was 
previously thought be an immune-privileged organ due to the paucity of native antigen 
presenting cells (APCs), low baseline levels of major histocompatibility complex (MHC) 
expression, absence of traditional lymphatic system and the notion that the NVU was 
impermeable to large molecular weight antibodies and lymphocytes and relative lethargy in 
rejection of foreign tissue engrafted into the CNS [17, 18]. 
 
Our understanding of the brain immune micro-environment has undergone a major shift in the 
recent years. It is now clear that microglia, macrophages, and dendritic cells act as powerful 
APCs in the CNS [19-21]. Recent demonstration of the perivascular lymphatic pathway in the 
CNS, now known as the ‘glympatics’, furthers our understanding of the drainage route through 
which the CNS microenvironment can interact with the better understood systemic immune 
system [22]. Animal studies from our lab previously demonstrated trafficking of 
superparamagnetic iron oxide particles from brain to cervical lymph nodes and that this 
interaction can be visualized using MRI [23]. 
 
Early studies with PD-1 inhibitors evaluating systemic tumors excluded patients with brain 
metastases. Although promising early data is emerging in brain metastases from various tumor 
types, very limited mature prospective data is available regarding their efficacy in brain tumors, 
specifically in brain metastases from NSCLC [24-29]. There are several ongoing clinical trials 
but the results are not available yet. Recently reported data from an open-label phase II trial 
evaluating the safety and activity of pembrolizumab monotherapy in brain metastases in 36 
untreated brain metastases(n=36, 18 melanoma, 18 NSCLC) showed a brain response rate of 
33% and was tolerated [30]. Similarly, initial reports on the safety of combining 

 
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pembrolizumab with radiation suggest that it is well tolerated with no reported grade 3 or 
greater acute toxicities [31, 32]. Our study will thus be vital in gathering additional vital data 
in a homogeneous group of patients with NSCLC brain metastases that will be helpful in 
designing future studies.  
 
Pembrolizumab in Brain Tumors 
Pembrolizumab, is a monoclonal antibody that blocks the programmed death-1 receptor (PD-
1, CD279), resulting in dis-inhibition of tumor-specific immune responses and is now FDA 
approved for the treatment of advanced and metastatic melanoma.  PD-1 blockade is thought 
to prevent PD-L1 expressed on tumor cells, stromal cells, and antigen-presenting cells (APC) 
from engaging PD-1 expressed on T cells, leading to more robust T cell activity resulting in 
anti-tumor effects. Pembrolizumab is now FDA approved for the treatment of advanced 
melanoma, 1st and 2nd line non-small cell lung carcinoma, head and neck cancer, and classical 
hodgkins lymphoma [6, 33]. Similarly, based on the excellent efficacy noted in the Keynote 
01 study, pembrolizumab is now approved for patients with metastatic advanced non-small 
cell carcinoma lung (NSCLC) across histologies [34]. Promising clinical activity was also 
noted in patients with recurrent/metastatic triple-negative (ER, PR, and HER2 negative) breast 
cancer [35]. There are multiple studies currently testing the efficacy of PD-1 inhibitors 
including pembrolizumab with bevacizumab in patients with recurrent glioblastoma 
(NCT02017717). The encouraging systemic anti-tumor effects makes pembrolizumab an ideal 
candidate for testing in primary and metastatic brain tumors that are frequently excluded from 
such studies. Patients with brain tumors have a very poor prognosis, and pembrolizumab is 
expected to provide good responses that are sustained in this population. 
 
Early studies with PD-1 inhibitors evaluating systemic tumors excluded patients with brain 
metastases. Although promising early data is emerging in brain metastases from various tumor 
types, very limited mature prospective data is available regarding their efficacy in brain tumors, 
specifically in brain metastases from NSCLC [24-29]. There are several ongoing clinical trials 
but the results are not available yet. Recently reported data from an open-label phase II trial 
evaluating the safety and activity of pembrolizumab monotherapy in brain metastases in 36 
untreated brain metastases(n=36, 18 melanoma, 18 NSCLC) showed a brain response rate of 
33% and was tolerated [30]. Similarly, initial reports on the safety of combining 
pembrolizumab with radiation suggest that it is well tolerated with no reported grade 3 or 
greater acute toxicities [31, 32]. Our study will thus be vital in gathering additional vital data 
in a homogeneous group of patients with NSCLC brain metastases that will be helpful in 
designing future studies.  
 
Immune Surveillance in the CNS And Blood Tumor Barrier: 
Despite significant improvement in our understanding the molecular pathogenesis of these 
brain tumors,drug deliver across the neurovascular unit and blood tumor barrier continues to 
be a major challenge [14]. Pembrolizumab is a large molecular weight monoclonal antibody. 
There is justifiable concern of large molecules being delivered into the CNS. However, the 
mechanism of action of PD-1 inhibitors such as pembrolizumab is at the systemic T-cell side 
of the immune synapse and not at the level of the PD-L1 ligand on the tumor cells that is inside 
the blood brain barrier.[36, 37] Immune cells that are part of the CNS immunosurveillance 
mechanism are known to be able to migrate in and out of the CNS more so under inflammatory 

 
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conditions and into the tumor microenvironment.[38, 39] One of the mechanisms by which 
tumors including triple negative breast cancer, melanoma and glioblastoma evade the immune 
surveillance is due to over expression of PD-L1 and its interactions with PD-1 receptors on T 
cells. Pembrolizumab blocks these interactions and hence is expected to enhance the antitumor 
immune response [6, 34, 40-44]. The concurrent use of standard of care including radiation in 
addition to pembrolizumab is justified by the synergistic action of radiation and checkpoint 
blockade immunotherapy [45]. 
 
Challenges in brain tumor trial design: pseudoprogression 
A major challenge in managing and designing trials for brain tumors is determining tumor 
response to therapy, and then differentiating response from recurrence or treatment-related 
changes. After radiation, a large majority of these tumors can paradoxically increase in size 
due to an inflammatory response called ‘pseudoprogression’. The term pseudoprogression 
describes the phenomenon of subacute radio-chemotherapy treatment-related sequelae in 
patients with brain tumors that presents as increasing or new contrast enhancement on MRI 
[46, 47]. These patients stabilize or recover spontaneously, usually without any change in 
treatment. As cancer immunotherapeutics are being tested in clinical trials, pseudoprogression 
is increasingly becoming a growing challenge that needs to be addressed [48]. It is estimated 
that over 10 -12% of patients develop pseudoprogression before eventually showing a response 
that can be captured by conventional response assessment criteria after immunotherapy. 
Similarly, over 30% develop imaging changes that are consistent with pseudoprogression after 
radiation [49]. This number is significantly higher when immunotherapy is combined with 
standard of care radiation. Current standard of care imaging or response assessment criteria do 
not have the ability to differentiate this immune response from true progression at any given 
time point. 
 
Currently used response assessment guidelines used such as RECIST 1.1 and WHO (for 
response assessment in systemic solid tumors) have consistently proven inadequate due to the 
unique anatomy of the brain, presence of the neuro vascular unit (also referred to as the blood 
brain barrier (BBB)), blood tumor barrier and heterogeneity of tumors like glioblastoma [2, 
50-52] [39-42]. It is now well understood that enhancement seen in MRI represents just the 
area with disrupted BBB and does not represent the whole tumor. The lack of reliable imaging 
biomarkers for response assessment is a major limiting factor in the development of new and 
effective therapies for brain tumors [51]. Further, agents like steroids and bevacizumab that 
are frequently used for symptom management in brain tumors can significantly alter imaging 
and alter response assessment. This lead to the development of the consensus based Response 
Assessment in Neuro-Oncology Working Group (RANO) criteria [53]. Based on RANO, all 
radiographic progression after 12 weeks post radiation is considered disease progression. The 
rate of pseudoprogression diagnosed at any time after radiation ranges from 9.3-31% [46]. 
Furthermore, around 30% of all pseudoprogression occurred beyond the 12-week RANO cut 
off including 2 cases occurring over 6 months after chemoradiation [3]. 
 
Figure 1 shows a case where the patient fulfilled criteria for progressive disease by RANO at 
3 months after radiation, but was shown to have pseudoprogression by low blood volume on 
ferumoxytol (an iron oxide nanoparticle blood pool contrast agent) imaging. 
 

 
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Ferumoxytol Imaging: Differentiating Pseudoprogression from True Progression 
Preliminary retrospective data from our group suggests that a novel MRI sequence called 
steady state (SS) imaging with ferumoxytol provides excellent spatial and temporal resolution 
and will fulfil this need. SS imaging cannot be performed with conventional gadolinium based 
MR contrast agents [54]. Ferumoxytol (Feraheme), is an iron oxide nanoparticle that is FDA-
approved as an intravenous iron supplement [55]. Over the last 20 years, we have demonstrated 
that ferumoxytol is a safe and effective contrast agent for brain tumor imaging, especially 
evaluating tumor vascularity and blood volumes [56-60]. Measurement of brain tumor relative 
cerebral blood volume (rCBV) with ferumoxytol may be helpful to clearly differentiate true 
tumor progression from pseudoprogression after chemo-radiotherapy [3, 54, 61, 62]. Based on 
our studies, ferumoxytol has been granted orphan drug status for the imaging of brain tumors. 
Dr. Edward Neuwelt holds the investigational new drug (IND) for ferumoxytol for the imaging 
indication, and the FDA has approved the use of ferumoxytol in conjunction with other 
therapeutic investigational drugs, in the setting of a clinical trial. 
 
This proposed pilot study will provide preliminary prospective data regarding the sensitivity 
and specificity of ferumoxytol steady state technology as a noninvasive biomarker in 
differentiating true progression from pseudoprogression after immunotherapy with the check 
point inhibitor pembrolizumab. Additionally, this study will generate pilot data regarding 
clinical activity of adding pembrolizumab to standard of care for primary and brain metastases. 
 
 
 
 
 
 

 
17 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Surgery 
Chemoradiotherapy 
3 mo of TMZ 
54 mo later, on 
TMZ 
 
 
 
Figure 1. 48 y/o F with glioblastoma.Column 1: preoperative T1+Gd MRI. Column 2: 
T1+Gd (gadolinium) MRI after maximal safe resection. Column 3:  T1+Gd, T2 and 
Ferumoxytol perfusion MRI after completion of standard CRT.  Note increased 
enhancement and low rCBV in the lesion (circle).  Column 4: T1+Gd, T2 and 
Ferumoxytol perfusion MRI after completion of 3 months of adjuvant TMZ.  Note further 
increase in enhancement with continued low rCBV (circle).  Column 5: T1+Gd MRI after 
54 months of adjuvant TMZ and resolution of pseudoprogression showing sustained 

 
18 
 
 
Our retrospective data from 68 patients with high grade gliomas suggest that 
pseudoprogression significantly increases overall survival from around 13 months to over 34 
months (Figure 2). 
 
 
 
Figure 2: Kaplan-Meier estimates of overall survival and progression-free survival by 
the presence of pseudoprogression 

 
19 
 
This difference was more pronounced in patients with MGMT methylation) [63]. It is now well 
recognized that inaccurate attribution of progression or pseudoprogression at enrollment or at 
the time of response assessment can significantly bias clinical trial outcomes based on 
progression free survival. In addition, it leads to premature therapy switching, potentially 
negating the benefits of a particular therapy. These radiographic changes are expected to 
increases after immune-modulatory therapy like PD-1 inhibitors such as pembrolizumab.  A 
subject on a potentially beneficial immune-modulatory therapy could be taken off a clinical 
trial because the subject may falsely fulfills  RANO or RECIST criteria for progression even 
though in reality, the radiographic progression could be due to pseudoprogression or response 
to immunotherapy. This is especially true in trials with immunotherapies where response may 
be slow or delayed. Figures 1 and 3 show pseudoprogression in glioblastoma. The patient 
described in figure 3 was on immune-modulatory therapy (EGFRv3 based vaccine study) and 
was taken of study due to erroneous diagnosis of true progression when the patient in fact had 
pseudoprogression and subsequently showed clinical and radiographic improvement. 
 
Early ferumoxytol scans: A biomarker for tumor vascularity 
Figure 3: This Patient received Celldex vaccine (an investigational immunotherapy that targets the 
tumor specific oncogene EGFRv3) at 5 and 6 months after CRT and 4 monthly cycles of adjunct 
Temozolamide. A Dramatic increased mass effect was noted 7-8 months post CRT and 1-2 months post 
Celldex vaccine. T1+Gd MRI Column 1: 7 months after CRT showing residual enhancing lesion in the 
right temporal lobe. Column 2: 8 months after CRT showing increase size of the lesion and exuberant 
vasogenic edema and mass effect on the lateral ventricle and midline shift. DSC perfusion MRI 8 
months after CRT showing decreased CBV in the enhancing area in the right temporal lobe, suggesting 
pseudoprogression. At this point Patient might be falsely classified as disease progression by updated 
RANO criteria.  Patient was continued on Temozolamide based on our blood volume measurements. 
He was given one dose of Avastin as an anti-edema measure in addition to high dose of steroids. He 
had to be eventually taken off the clinical because the trial excluded patients on Avastin .Column 3:  9 
months after CRT and 4 weeks after one dose of bevacizumab MRI showed significant improvement 
in the enhancement, vasogenic edema and mass effect. Column 4: 10 months after CRT and 8 weeks 
after bevacizumab showing minimal increase of enhancement and mass effect, still significantly better 
than before bevacizumab. This case clearly demonstrates the inadequacies of conventional MRI scans 
and RANO criteria and shows blood volume measurements is better imaging biomarker than 
enhancement. 

 
20 
 
Prior studies have demonstrated elevated relative cerebral blood volume (rCBV>1.75) in 
actively growing tumor while pseudoprogression shows low rCBV in primary brain tumors [3, 
4, 46, 47, 61, 64-66]. Dynamic susceptibility contrast (DSC) perfusion, which provides an 
estimate of rCBV in tumor and brain, has shown value in distinguishing primary from 
metastatic cerebral tumors and assessing response to therapy. It adds little to no extra cost to a 
clinical MRI scan, and is rapidly becoming the most widely used advanced MRI technique in 
brain tumor imaging. rCBV analysis is especially helpful in  differentiating progression from 
response to therapy (pseudoprogression). Using a lesion rCBV threshold of >2.0 yields 56% 
sensitivity and 100% specificity in the differentiation of tumor progression from treatment 
injury [54]. The use of ferumoxytol iron oxide nanoparticles which have no early leakage 
across the blood brain barrier has further improved rCBV analysis. Use of these improved MR 
perfusion techniques has led to very high accuracy in this important diagnostic dilemma, and 
may be predictive of outcome and long-term survival in high grade gliomas [61] (Figure 
4).Varallyay and colleagues from our group have described the use of ferumoxytol MRI to 
obtain a high-resolution steady state-CBV image that differentiates regions of high vascularity 
and active tumor growth (Figure 5, 6) [54, 61].  Steady-state MRI with ferumoxytol further 
improves rCBV measurement by providing high spatial resolution (Figure 7) [54]. This is 
particularly helpful in imaging cortical lesions and lesions near blood vessels with very high 
resolution. High resolution rCBV measurement is very helpful in differentiating 
pseudoprogression from true progression not only in glioblastoma after CRT but also after SRS 
in brain metastases as well (Figure 8). 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
21 
 
 
 
Figure 5: Brain imaging using ferumoxytol: (A) High resolution images showing 
intravascular iron. (B) Delayed enhancement24 hours after ferumoxytol 
administration. 
A 
Figure 6. Comparison of steady-state-cerebral blood volume (SS-CBV) and 
dynamic susceptibility contrast (DSC)-CBV maps in a glioblastoma patient. (A) T1-
weighted postgadoteridol scan describes the multifocal signal abnormalities. In 
corresponding slices, the SS-CBV (B) and DSC-CBV (C) maps show increased 
areas of CBV referring to highly vascular tumor areas. Note the mismatch between 
the most enhancing region (arrow) and the highest CBV values. Reprinted from 
Varallyay et al. (2013). 

 
22 
 
 
 
 
 
 
 
Another major problem with response assessment is the use of VEGF inhibitors like 
bevacizumab or corticosteroids. These agents can alter the neurovascular unit around the tumor 
and decrease contrast enhancement (pseudo-response) when measured by conventional 
response criteria. Bevacizumab has failed to show significant survival benefits but is frequently 
used as an anti-edema measure [67-69].  
 
Our preliminary data suggests that use of bevacizumab may alter rCBV measurements in high 
grade gliomas. For the purpose of this study, a short course of up to 3 doses of bevacizumab 
may be allowed, when clinically indicated, as an anti-edema measure and will not be criteria 
for exclusion. Bevacizumab is preferred over steroids when studying immune-modulatory 
therapies, since use of steroids can potentially dampen the immune response and outcomes. 

 
23 
 
Study MRI will be performed prior to the start of bevacizumab therapy whenever possible. 
Imaging data from subjects who require more than 3 doses of bevacizumab will be stratified 
and analyzed separately. A separate analysis of subjects based on their bevacizumab and 
steroid dose will be performed as part of the final analysis. Since this is not a randomized trial 
and the need for bevacizumab cannot be predicted prior to enrollment, stratification prior to 
enrollment is not possible and analysis will be performed post enrollment. Currently, the 
differences in the pathophysiology or response to bevacizumab in pseudoprogression resulting 
radiation or PD-1 inhibitors is not clear. This study will provide critical data that can provide 
insight to the use of bevacizumab as a steroid sparing agent to control the edema and mass 
effect. There are several ongoing studies evaluating the efficacy of the combination in brain 
tumors.   
 
Delayed Ferumoxytol imaging: A biomarker for inflammation 
In addition to uptake by the reticuloendothelial system, ferumoxytol and other iron oxide 
nanoparticles are taken up by tumor-associated macrophages [70-72] and brain microglia [73]. 
Delayed imaging of ferumoxytol in the CNS (figure 7) may therefore provide an important 
biomarker of inflammation and immune response in brain tumors [70, 74-76]. We have 
demonstrated that ferumoxytol iron oxide nanoparticles are taken up by phagocytic cells over 
hours to days after IV infusion (Figure 9). We are actively investigating the utility of 
ferumoxytol for imaging inflammation, assessing nanoparticle uptake into tumor-associated 
macrophages/microglia in inflammatory lesions (Figure 10). Our animal models suggest that 
the enhancement seen on T1 weighted images at >24 hr time point after ferumoxytol 
administration is believed to reflect the extent of local inflammation. This study will provide 
preliminary data regarding the significance of volume and extent of delayed ferumoxytol 
enhancement after immunotherapy. 
 
 
FIGURE 9.  Immunofluorescent histochemistry 
confirms ferumoxytol uptake by macrophages and 
astrocytes at and around inflammatory lesions.  
Twenty-four 
hours 
after 
ferumoxytol 
administration, 7 µm-thick serial rat and human 
brain sections were simultaneously incubated with 
anti-Dx1 and either anti-CD68 or anti-GFAP, 
respectively. There was intracellular Dx1 staining 
with nuclear exclusion in CD68-positive cells in 
rat, as well as within GFAP-positive cells outside 
of a vessel in human brain. (Scale bar = 20 
microns) 
 
 
DX1 
CD68 
GFAP 
DX1 
Rat brain 
with Non-
Small cell 
carcinoma  
Human 
brain 
with 
GBM 

 
24 
 
Our publications indicate that ferumoxytol imaging at early time points (24 hr) provides 
additional information regarding tumor vascularity and improves visualization of vascular 
malformations [74] and while at later time points ( >24 hrs) ( figure 5 and 7), it may help better 
detect the inflammatory component [77]. Delayed ferumoxytol-enhanced brain MRI was also 
shown to be useful in the diagnosis of CNS inflammatory disorders and lymphoma and is also 
useful for patients with renal compromise at risk of nephrogenic systemic fibrosis who are 
unable to receive GBCA [75]. 
 
Ferumoxytol steady state imaging for lesions outside the CNS: differentiating disease 
progression from flair response. 
Although our work concentrates on CNS metastases, similar imaging modalities may be useful 
for the assessment of therapeutic efficacy and immune response in systemic metastases. The 
phenomenon of immune flare in solid non-CNS tumors may be equivalent to 
pseudoprogression in CNS malignancies. Steady-state feMRI is being evaluated to assess 
tumor vasculature in a variety of systemic cancers including those in the breast, pancreas and 
prostate [63, 78, 79]. A subset of subjects enrolled in this study may also have systemic 
metastases. This imaging technique uses ferumoxytol to assess tumor vascularity, and is 
analogous to our work in the CNS. This will allow direct comparison of these metastatic sites, 
to determine if we can delineate immune flare from therapeutic response and the immune 
component of flare. In both CNS and systemic metastases, we hypothesize that perfusion MRI 
using steady-state ferumoxytol imaging will provide a measure of rCBV indicative of active 
tumor growth, while delayed imaging of ferumoxytol may provide an important biomarker of 
inflammation and immune response. We hypothesize that feMRI techniques will provide a 
 

 
25 
 
better modality than immune response criteria for evaluating the response to pembrolizumab 
in NSCLC metastases. 
 
OHSU Blood-Brain Barrier (BBB) Program: experience with ferumoxytol 
For the past three decades the OHSU Blood-Brain Barrier Program has developed significant 
laboratory and clinical expertise in imaging the CNS [50, 51]. We have shown that ferumoxytol 
is a safe and effective contrast agent that is not inferior to GBCA for brain tumor imaging, and 
can provide significantly better information regarding the tumor vasculature (Figure 11). We 
have developed multiple clinical trials to assess ferumoxytol as a MRI contrast agent for 
anatomic and dynamic MRI of intracerebral tumors. Based on our studies, ferumoxytol has 
been granted orphan drug status for the imaging of brain tumors and we are working with the 
FDA to move towards market approval of ferumoxytol for brain tumor MRI. We have clarified 
with the FDA that ferumoxytol can be used as diagnostic imaging agent in addition to 
pembrolizumab which is the therapeutic agent being evaluated, both under separate 
investigational new drug applications (IND).  OHSU along with the Veterans Administration 
Medical center, Portland, Oregon is the largest academic medical center and cancer center in 
the state with a large referral base from adjacent states as well. The high volume of patients as 
well as expertise available at OHSU, including access to advanced imaging capabilities, 
ensures attainment of anticipated accrual targets and fulfilment of the objectives of this study. 
 
4.1 
Trial Description 
See section 2.0 
 
4.2 
Pharmaceutical and Therapeutic Background 
The importance of intact immune surveillance in controlling outgrowth of neoplastic 
transformation has been known for decades.  Accumulating evidence shows a correlation 
between tumor-infiltrating lymphocytes (TILs) in cancer tissue and favorable prognosis in 
various malignancies.  In particular, the presence of CD8+ T-cells and the ratio of CD8+ 
effector T-cells / FoxP3+ regulatory T-cells seems to correlate with improved prognosis and 
long-term survival in many solid tumors. 
 
The PD-1 receptor-ligand interaction is a major pathway hijacked by tumors to suppress 
immune control.  The normal function of PD-1, expressed on the cell surface of activated T-
cells under healthy conditions, is to down-modulate unwanted or excessive immune responses, 
including autoimmune reactions.  PD-1 (encoded by the gene Pdcd1) is an Ig superfamily 
member related to CD28 and CTLA-4 which has been shown to negatively regulate antigen 
receptor signaling upon engagement of its ligands (PD-L1 and/or PD-L2).  The structure of 
murine PD-1 has been resolved.  PD-1 and family members are type I transmembrane 
glycoproteins containing an Ig Variable-type (V-type) domain responsible for ligand binding 
and a cytoplasmic tail which is responsible for the binding of signaling molecules.  The 
cytoplasmic tail of PD-1 contains 2 tyrosine-based signaling motifs, an immunoreceptor 
tyrosine-based inhibition motif (ITIM) and an immunoreceptor tyrosine-based switch motif 
(ITSM).  Following T-cell stimulation, PD-1 recruits the tyrosine phosphatases SHP-1 and 
SHP-2 to the ITSM motif within its cytoplasmic tail, leading to the dephosphorylation of 
effector molecules such as CD3ζ, PKCθ and ZAP70 which are involved in the CD3 T-cell 
signaling cascade.  The mechanism by which PD-1 down modulates T-cell responses is similar 

 
26 
 
to, but distinct from that of CTLA-4 as both molecules regulate an overlapping set of signaling 
proteins.  PD-1 was shown to be expressed on activated lymphocytes including peripheral 
CD4+ and CD8+ T-cells, B-cells, T regs and Natural Killer cells.  Expression has also been 
shown during thymic development on CD4-CD8- (double negative) T-cells as well as subsets 
of macrophages and dendritic cells.  The ligands for PD-1 (PD-L1 and PD-L2) are 
constitutively expressed or can be induced in a variety of cell types, including non-
hematopoietic tissues as well as in various tumors.  Both ligands are type I transmembrane 
receptors containing both IgV- and IgC-like domains in the extracellular region and contain 
short cytoplasmic regions with no known signaling motifs.  Binding of either PD-1 ligand to 
PD-1 inhibits T-cell activation triggered through the T-cell receptor. 
 
PD-L1 is expressed at low levels on various non-hematopoietic tissues, most notably on 
vascular endothelium, whereas PD-L2 protein is only detectably expressed on antigen-
presenting cells found in lymphoid tissue or chronic inflammatory environments.  PD-L2 is 
thought to control immune T-cell activation in lymphoid organs, whereas PD-L1 serves to 
dampen unwarranted T-cell function in peripheral tissues.  Although healthy organs express 
little (if any) PD-L1, a variety of cancers were demonstrated to express abundant levels of this 
T-cell inhibitor.  PD-1 has been suggested to regulate tumor-specific T-cell expansion in 
subjects with melanoma (MEL).  This suggests that the PD-1/PD-L1 pathway plays a critical 
role in tumor immune evasion and should be considered as an attractive target for therapeutic 
intervention. 
 
Pembrolizumab is a potent and highly selective humanized monoclonal antibody (mAb) of the 
IgG4/kappa isotype designed to directly block the interaction between PD-1 and its ligands, 
PD-L1 and PD-L2.  KeytrudaTM (pembrolizumab) has recently been approved in the United 
States for the treatment of subjects with  advanced melanoma, 1st and 2nd line non-small cell 
lung carcinoma, head and neck cancer, and classical hodgkins lymphoma [6, 33]. 
 
Our preliminary data suggests that use of bevacizumab may alter rCBV measurements in high 
grade gliomas. For the purpose of this study, a short course of up to 3 doses of bevacizumab 
may be allowed, when clinically indicated, as an anti-edema measure and will not be criteria 
for exclusion. Bevacizumab is preferred over steroids when studying immune-modulatory 
therapies, since use of steroids can potentially dampen the immune response and outcomes. 
Study MRI will be performed prior to the start of bevacizumab therapy whenever possible. 
Imaging data from subjects who require more than 3 doses of bevacizumab will be stratified 
and analyzed separately. A separate analysis of subjects based on their avastin and steroid dose 
will be performed as part of the final analysis. Currently, the differences in the pathophysiology 
or response to bevacizumab in pseudoprogression resulting radiation or PD-1 inhibitors is not 
clear. This study will provide critical data that can provide insight to the use of bevacizumab 
as a steroid sparing agent to control the edema and mass effect. There are several ongoing 
studies in several tumor types (including brain metastases and primary brain tumors) 
evaluating the efficacy of the pembrolizumab and bevacizumab combination, however no 
study has a completed dataset. However, none of the studies are investigating the role of 
bevacizumab in pseudoprogression. 
 

 
27 
 
4.3 
Preclinical and Clinical Trial Data 
Refer to the Investigator’s Brochures/Package Inserts for Preclinical and Clinical data 
(Supplemental Material, section 15). 
 
4.3.1 Rationale for the Trial and Selected Subject Population 
Subjects with metastatic brain tumors are frequently excluded from clinical trials of systemic 
disease. Systemic cytotoxic chemotherapy has consistently failed to show benefit in brain 
metastases due to the presence of the blood brain barrier, among other things [14, 64]. 
Similarly, prognosis continues to be poor for glioblastoma patients treated with standard chemo 
radiation [80]. 
 
Pembrolizumab acts on the T-cells in the periphery to augment systemic immune response and 
thus does not have to cross the blood brain barrier. A synergetic effect of combined 
immunotherapy and stereotactic radiation is expected to promote the release of tumor specific 
antigens that can then direct antigen- presenting cells to induce a T cell mediated immune 
response. Safety and efficacy of pembrolizumab for systemic non–small-cell lung cancer and 
melanoma is now well described in multiple clinical trials.[5, 7, 34, 81] . There is promising 
preliminary evidence of efficacy.[35, 82] 
 
Since pembrolizumab acts at the level of T–cells, it does not have to cross the blood brain 
barrier and hence is expected to be efficacious in our cohort with brain metastases as well.  
This pilot study will prospectively evaluate a novel imaging ferumoxytol steady state imaging 
as a biomarker that can differentiate true from pseudoprogression in the context if 
immunotherapy with pembrolizumab. This study will also provide valuable pilot data 
regarding the efficacy of pembrolizumab in brain tumors. Larger studies will be designed using 
this data. 
 
Significance: 
With immunotherapy, a transient increase in size of lesion on imaging called flair response is 
frequently seen before a response is noted [48]. A similar increase in size of the lesion is noted 
after radiation therapy in primary brain tumors [46, 47, 63, 83]. Currently, subjects who have 
imaging changes within the first 12 weeks after chemo-radiation are followed up with serial 
scans to confirm true vs pseudoprogression and may sometimes be excluded from clinical trials 
due to the lack of validated noninvasive methods to distinguish true progression from 
pseudoprogression [84]. 
 
Our group has demonstrated that rCBV measured by ferumoxytol steady state imaging is very 
helpful in distinguishing pseudoprogression from true disease progression in brain tumors [54, 
62, 63]. Accurate diagnosis of pseudoprogression will prevent subjects being taken off a 
potentially beneficial clinical trial when there is an anatomical increase in tumor burden after 
radiation or immunotherapy. This study will validate and determine the sensitivity and 
specificity of ferumoxytol steady state imaging in distinguishing the two entities. This study 
will also provide information that will be invaluable in designing future trials for metastatic as 
well as primary brain tumors and help improve the practice of neuro-oncology. 
 

 
28 
 
4.3.2 Rationale for Dose Selection/Regimen/Modification 
Pembrolizumab 
An open-label Phase I trial (Protocol 001) is being conducted to evaluate the safety and clinical 
activity of single agent MK-3475.  The dose escalation portion of this trial evaluated three dose 
levels, 1 mg/kg, 3 mg/kg, and 10 mg/kg, administered every 2 weeks (Q2W) in subjects with 
advanced solid tumors.  All three dose levels were well tolerated and no dose-limiting toxicities 
were observed.  This first in human study of MK-3475 showed evidence of target engagement 
and objective evidence of tumor size reduction at all dose levels (1 mg/kg, 3 mg/kg and 10 
mg/kg Q2W).  No MTD has been identified to date.  10.0 mg/kg Q2W, the highest dose tested 
in PN001, will be the dose and schedule utilized in Cohorts A, B, C and D of this protocol to 
test for initial tumor activity.  Recent data from other clinical studies within the MK-3475 
program has shown that a lower dose of MK-3475 and a less frequent schedule may be 
sufficient for target engagement and clinical activity. 
 
PK data analysis of MK-3475 administered Q2W and Q3W showed slow systemic clearance, 
limited volume of distribution, and a long half-life (refer to IB).  Pharmacodynamic data (IL-
2 release assay) suggested that peripheral target engagement is durable (>21 days).  This early 
PK and pharmacodynamic data provides scientific rationale for testing a Q2W and Q3W 
dosing schedule. 
 
A population pharmacokinetic analysis has been performed using serum concentration time 
data from 476 subjects. Within the resulting population PK model, clearance and volume 
parameters of MK-3475 were found to be dependent on body weight. The relationship between 
clearance and body weight, with an allometric exponent of 0.59, is within the range observed 
for other antibodies and would support both body weight normalized dosing or a fixed dose 
across all body weights.  MK-3475 has been found to have a wide therapeutic range based on 
the melanoma indication.  The differences in exposure for a 200 mg fixed dose regimen relative 
to a 2 mg/kg Q3W body weight based regimen are anticipated to remain well within the 
established exposure margins of 0.5 – 5.0 for MK-3475 in the melanoma indication. The 
exposure margins are based on the notion of similar efficacy and safety in melanoma at 10 
mg/kg Q3W vs. the proposed dose regimen of 2 mg/kg Q3W (i.e. 5-fold higher dose and 
exposure). The population PK evaluation revealed that there was no significant impact of 
tumor burden on exposure. In addition, exposure was similar between the NSCLC and 
melanoma indications. Therefore, there are no anticipated changes in exposure between 
different indication settings. 
 
The choice of the 200 mg every 3 weeks is an appropriate dose based on simulations performed 
using the population PK model of pembrolizumab showing that the fixed dose of 200 mg every 
3 weeks will provide exposures that 1) are optimally consistent with those obtained with the 2 
mg/kg dose every 3 weeks, 2) will maintain individual subject exposures in the exposure range 
established in melanoma as associated with maximal efficacy response and 3) will maintain 
individual subjects exposure in the exposure range established in melanoma that are well 
tolerated and safe. 
 
This fixed FDA approved dose regimen (200 mg, intravenously every 3 weeks) will simplify 
the dosing regimen to be more convenient for physicians and to reduce potential for dosing 

 
29 
 
errors.  A fixed dosing scheme will also reduce complexity in the logistical chain at treatment 
facilities and reduce wastage. 
 
Ferumoxytol 
On June 20, 2009, the FDA approved ferumoxytol (Feraheme™) to treat Iron Deficiency 
Anemia and Adult Chronic Kidney Disease Patients. The recommended dose is an initial 510 
mg IV injection followed by a second 510 mg IV injection three to eight days later. 
Ferumoxytol is now commercially available in the U.S.A. 
 
Ferumoxytol has provided improved imaging with minimal safety concerns even using 
extremely high doses in preclinical trials with animals, in vitro using human blood cells, and 
in multiple IND sponsored studies. Ferumoxytol has few systemic reactions and can be given 
as a bolus for MRA analysis of tumor vasculature. The ferumoxytol Investigator’s brochure 
2012 contains detailed information of preclinical and clinical safety studies as summarized 
below.  
 
Temozolomide for patients with glioblastoma (arm 2) will be as per clinical standard of care. 
 
4.3.3 Preclinical studies  
A series of nonclinical toxicity studies were conducted in rats and beagle dogs to assess the 
safety of ferumoxytol. Repeat-dose toxicity studies with ferumoxytol up to 12 mg Fe/kg/day 
for 13 weeks in rats (cumulative exposure approximately 12 times the exposure of a human 
therapeutic course of 1.02 g of ferumoxytol on a mg/m2 basis) and dogs (cumulative exposure 
approximately 40 times the exposure of a human therapeutic course of 1.02 g of ferumoxytol 
on a mg/m2 basis) demonstrated dose-dependent decreases in body weight gain and food 
consumption, and increases in pigmentation intensity. No systemic toxicity or immunotoxicity 
was observed at the relevant clinical doses. Changes in red blood cell (RBC) counts, 
hemoglobin (Hgb) and serum iron, increases in liver and spleen weight, and the accumulation 
of iron-positive pigmentation in various organs were observed as expected with the 
administration of an iron-containing agent.  
 
Ferumoxytol showed no potential for mutagenic or clastogenic activity in several genotoxicity 
tests. Administration of 100 mg Fe/kg ferumoxytol (the highest dose studied) had minimal 
potential for inducing an anaphylactic response in a rat model of hypersensitivity and did not 
appear to cause irritation after IV administration in rabbits or guinea pigs. Ferumoxytol did not 
cause any visible flocculation, precipitation, or sedimentation when incubated with human 
serum or plasma (at concentrations up to 15 mg Fe/mL), caused only slight hemolysis in human 
erythrocytes and did not alter clotting times. No effects on the central nervous, respiratory, and 
renal systems were observed in mice, rats, and beagle dogs; only a minimal cardiovascular 
effect was observed in guinea pigs (1of 9 animals had a mild decrease in mean arterial blood 
pressure).  
 
The toxicity of polyglucose sorbitol carboxymethylether (PSC, the carbohydrate coating of the 
iron oxide core of ferumoxytol) was evaluated in two repeat-dose studies in rats and dogs, with 
daily IV administration for 2 weeks. The PSC coating was well tolerated up to the highest 
tested dose of 1600 mg PSC/kg/day in rats and 750 mg PSC/kg/day in dogs. 

 
30 
 
 
The pharmacokinetics (PK) and drug metabolism of ferumoxytol have been evaluated in rats, 
rabbits, and guinea pigs and these studies demonstrated that the plasma half-life increased with 
increasing dosage. The highest tissue concentrations of ferumoxytol were found in the liver, 
spleen, and central lymph node pool. Studies with radiolabeled drug product demonstrated that 
renal elimination of the iron in ferumoxytol was insignificant, while the carbohydrate coating 
was significantly excreted in the urine (72% to 78%) and feces (10% to 19%). This processing 
of ferumoxytol indicates that the iron contained in ferumoxytol is metabolized in tissues with 
reticuloendothelial cells, which incorporate the administered iron for uptake, storage, and the 
synthesis of hemoglobin.  
 
4.3.4 Clinical Studies 
4.3.4.1 Registrational program 
  
From Ferumoxytol Investigator’s Brochure 2009: 
The ferumoxytol clinical development program was comprised of eleven studies. These 
included three Phase 1 studies (two dose-escalation studies and a study of the 
electrocardiographic/QTC effects of ferumoxytol), two Phase 2 studies that evaluated the 
safety and efficacy of ferumoxytol for iron replacement in patients with Chronic Kidney 
Disease (CKD), and two Phase 2 imaging studies that assessed the feasibility of ferumoxytol 
as an MRI contrast agent. There were three open-label, Phase 3 studies that examined the 
efficacy and safety of ferumoxytol relative to oral iron in patients with CKD, Stages 1-5, either 
on or not on dialysis. A fourth Phase 3 study in patients with any stage of CKD evaluated the 
safety of ferumoxytol relative to placebo in a cross-over, double-blinded manner.  Ferumoxytol 
has been evaluated at exposures of up to 2 x 510 mg, including two courses of 2 x 510 mg in 
three of the four Phase 3 studies. Specifically, the following regimens of ferumoxytol were 
given during the clinical program:  
• ≤4 mg Fe/kg  
• 1x 125 mg  
• 1x 250 mg  
• 1x 510 mg  
• 8x 128 mg  
• 4x 255 mg  
• 2x 510 mg 
 
Approximately 1,740 patients were exposed to ferumoxytol in the entire AMAG clinical 
development program, including approximately 1,509 patients in the Phase 3 studies. Only one 
patient (0.06% of all patients exposed to ferumoxytol) experienced an anaphylacoid reaction 
following treatment with ferumoxytol; this patient had a history of multiple drug allergies and 
experienced an anaphylactoid reaction (hot flashes and itching, with no respiratory 
compromise) and severe hypotension a few minutes after receiving ferumoxytol. 
 
There have been no deaths that were considered to be related to ferumoxytol treatment. There 
were 28 deaths in the clinical program, all of which have occurred in Phase 3 studies, with 16 
deaths among the 1,740 patients exposed to ferumoxytol (0.9%) and 8 deaths among the 296 
patients exposed to oral iron (2.7%). Four deaths occurred in patients who had signed an 
informed consent for enrollment but did not receive any iron agents. All deaths in the clinical 

 
31 
 
program have been in patients with CKD, who have a high risk of death due to cardiovascular 
disease and other causes.  In completed studies that used oral iron as a comparator, there was 
a lower rate of serious adverse events (SAEs) among patients exposed to ferumoxytol than 
among patients exposed to oral iron: 4.4% of ferumoxytol treated patients (64 of 1,451 
patients) vs. 10.7% of oral iron-treated patients (17 of 159 patients). Patients exposed to 
placebo had the lowest rate of SAEs (1.7%; 13 of 780 patients).  One patient each following 
ferumoxytol (0.1%), oral iron (0.6%), and placebo (0.1%) experienced a SAE that was 
considered by the investigator to be related to treatment.  In the Phase 3 Study 62,745-5, which 
enrolled CKD patients undergoing hemodialysis, 31 of 199 (15.6%) patients experienced a 
SAE following ferumoxytol administration and 8 of 70 (11.4%) patients experienced a SAE 
following oral iron administration.  These data were taken from an unlocked database and 
therefore are preliminary. In the Phase 3 studies in patients with CKD (62,745-5; 62,745-6; 
62,745-7 and 62,745-8, in which approximately 1,509 patients were exposed to ferumoxytol), 
the most common adverse events following ferumoxytol administration included nausea, 
diarrhea, dizziness, headache, and peripheral edema.  These adverse events were usually more 
common in the oral iron group than the ferumoxytol group (in Studies 62,745-5; 62,745-6 and 
62,745-7, which utilized oral iron as a comparator). Hypotension was one of the more common 
adverse events in Study 62,745-7 and occurred more frequently in the ferumoxytol group 
(5.0%) than the oral iron group (1.4%).  By contrast, preliminary data showed that there were 
lower rates of hypotension in Study 62,745-5 (1.8%, 1.7%, and 0% in the ferumoxytol 2x510 
mg, ferumoxytol 4x255 mg, and oral iron groups, respectively).  Hypotension rates were 
similar between the ferumoxytol and placebo groups (1.3% vs. 0.8%) in the large safety study, 
Study 62,745-8; there were no hypotension adverse events in Study 62,745-6.  
 
An independent Data Monitoring Committee met to review the clinical safety data for all Phase 
3 studies in October 2005, February 2006, June 2006, October 2006, and March 2007; they 
identified no safety concerns. The highest dose used was 4mg/kg (280mg for a 70kg patient).  
If there is no history of iron over load, there is no need to screen for iron over load since 0.5 g 
will not hurt patients, even if they have asymptomatic iron over load.   
 
4.3.4.2 Post-marketing Program-From Ferumoxytol Investigator’s Brochure Released 
on February 15, 2018: 
Since approval, AMAG has conducted two post-marketing clinical trials (Protocol Number 
FER-CKD-201 and AMAG-FER-CKD-401). FER-CKD-201 was a randomized, open-label 
trial that compared the safety and efficacy of ferumoxytol to iron sucrose for the treatment of 
IDA in CKD subjects either on or not on dialysis. In this trial, 162 patients were randomized 
in a 1:1 ratio to either ferumoxytol or iron sucrose. Ferumoxytol was administered as a 1.02 g 
course given as a regimen of 2 x 510 mg within 2 to 8 (5±3) days. The most common AEs 
among ferumoxytol treated subjects were nausea (7.5%) and muscle spasms (5.0%). Adverse 
events occurring in ≥2.0% of subjects treated with ferumoxytol included: nasopharyngitis, 
URI, headache, hyperkalemia, and cough (3.8%); peripheral edema, constipation, diarrhea, 
hypotension, hypoglycemia, and anemia (2.5%). There was only one ferumoxytol related SAE 
in the FER-CKD-201 study, 1 event of anaphylactic reaction in 1 subject occurred on the same 
day as the subject’s first dose of ferumoxytol. The AMAG-FER-CKD-401 study was an 
international Phase IV, randomized, open-label, active controlled multicenter trial of the safety 
and efficacy of ferumoxytol (2x510 mg) compared with IV iron sucrose (10x100 mg) in the 

 
32 
 
treatment of iron deficiency anemia in 293 patients with CKD on hemodialysis. Overall related 
AEs, related SAEs and protocol-defined AEs of special interest were reported 4.4%, 0% and 
17.4%. 
 Imaging Program: 
The potential use of ferumoxytol as an MRI contrast agent was evaluated in open-label 
feasibility studies, including one Phase I study (Protocol Number 7228-01) in healthy 
volunteers and two Phase II studies (Protocol Numbers 58,254-2 and 58,254-5) in subjects 
undergoing a diagnostic imaging procedure. In the combined studies, 70 imaging subjects were 
exposed to a single administration of ≤4 mg Fe/kg ferumoxytol. Results from these studies 
demonstrated that ferumoxytol was useful in visualizing the arterial circulation. Ferumoxytol 
has a long blood half-life, unlike the majority of other MRI contrast agents, enabling arterial 
and venous imaging for a period of several hours following injection. 
 
4.3.4.3 Post-Marketing Program- March of 2015 FDA Black Box Warning 
In March of 2015 the FDA placed a black box warning on ferumoxytol stating: 
WARNING: RISK FOR SERIOUS HYPERSENSITIVITY/ANAPHYLAXIS REACTIONS 
Fatal and serious hypersensitivity reactions including anaphylaxis have occurred in patients 
receiving Feraheme. Initial symptoms may include hypotension, syncope, unresponsiveness, 
cardiac/cardiorespiratory arrest.  
 
•Only administer Feraheme when personnel and therapies are immediately available for the 
treatment of anaphylaxis and other hypersensitivity reactions. 
 
•Observe for signs or symptoms of hypersensitivity reactions during and for at least 30 minutes 
following Feraheme infusion including monitoring of blood pressure and pulse during and after 
Feraheme administration. 
 
•Hypersensitivity reactions have occurred in patients in whom a previous Feraheme dose was 
tolerated. 
 
In the black box warning the FDA updated their recommendations of how ferumoxytol should 
be given.  The option to give ferumoxytol (510mg) as a fast undiluted injection in 
approximately 1 minute has been removed.  It was recommended that ferumoxytol (510mg) 
be given over at least 15 minutes. To accommodate for this, the dose of ferumoxytol in this 
study will be given in three separate, fractionated doses. The rate of administration of the 
second and third doses will be slowed down to no faster than 1 mL/s.  
 
Post-Marketing Safety 
AMAG’s pharmacovigilance system proactively reviews spontaneous reports. Routine 
surveillance of events is performed daily and monthly signal detection and evaluation 
processes monitor and update the safety profile. To date the information received from the 
post-marketing setting is consistent with the known safety profile of ferumoxytol. 
 
As shown in Table 1, cumulative postmarketing reporting rates for serious AESIs (adverse 
events of special interest) with ferumoxytol since product approval (30 June 2009) have 
remained low. These event reporting rates are rare and very rare using CIOMS standardized 

 
33 
 
assessment, and no new safety trends or signals have been identified. The reporting rates for 
all AEs remained low and declined over time. In addition, the reporting rates for all serious 
events including HSRs have declined following the change in the prescribing information to 
administration with infusion instead of rapid injection (March 2015). Overall, there is no new 
safety signal arising from the review of the anaphylactic reactions/shock and hypersensitivity 
reaction events. The risk of anaphylaxis/hypersensitivity linked to iron agents is well 
recognized and the need for special caution when administrating ferumoxytol is adequately 
addressed in the US Prescribing Information. The available information from these events does 
not change the safety profile of ferumoxytol. 
 
Table 1 
Reporting Rates of Serious AESIs by Ferumoxytol Administration 
AESI 
Rapid Injection               
(2009-31 Mar 2015)            
Estimated Exposure: 
1,216,518 
Diluted infusion 
(1 Apr 2015-31 Mar 2017)      
Estimated Exposure: 556,117 
No of Cases 
Reporting 
Rate 
(Estimated) 
No of Cases 
Reporting 
Rate 
(Estimated) 
Anapyhlaxis 
95 
0.0078 
16 
0.0029 
Hypersensitivity 
(severe) 
73 
0.0060 
5 
0.00089 
Cardiac 
disorders 
371 
0.0030 
4 
0.00071 
Hypotension 
(serious) 
72 
0.0059 
2 
0.00035 
Syncope, loss of 
consciousness, 
unresponsive 
44 
0.0036 
42 
0.00071 
Fatal 
481 
0.0040 
43 
0.00071 
 1Includes cases received in April 2015 with event onset in March 2015 (AMAG201500330). 
2Follow-up received on AEOI reported in Q2, per HCP due to underlying disease (epilepsy) and not ferumoxytol 
(AMAG201600940). 
3Case AMAG201602875: As per the treating physician, the death is not related to ferumoxytol; Case AMAG201601453: 
Death due to metastasis of neoplasm after 6 months of discontinuation of ferumoxytol therapy. 
 
 
Based on communication with AMAG Pharmaceuticals, manufacturer of ferumoxytol, all 
recommendations apply to iron replacement therapy where infusion rate and dilution do not 
impact efficacy. However, for an imaging indication certain infusion parameters are required 
to gain information, such as dynamic imaging. Increased infusion rate will only affect the first 
injection of 1 mg/kg, which is a small fraction of the full therapeutic dose, and therefore may 
minimally increase the risk of adverse reactions. The next two injections are given at a slower 
rate. The recommended 15 minutes has no scientific basis, it has been chosen arbitrarily. For 
MR imaging stopping the scanner for 15 minutes would be disadvantageous. Applying 
multiple injections, which is not the case with iron replacement therapy, may increase safety, 

 
34 
 
compared to continuous injection. This may contribute to the fact that in our patient population 
only minor adverse reactions have been reported. 
 
4.3.4.4 OHSU Toxicity Data for Ferumoxytol 
A total of 800 infusions of ferumoxytol have been completed on 410 study subjects as part of 
OHSU’s Blood Brain Barrier sponsored IRB approved protocols. The dose has ranged from 
75 to 510 mg of ferumoxytol (0.5 to 11 mg/kg). Toxicities for this group as of May 1, 2017 
show no grade 4 or 5 toxicities (CTCAE version 3) that were attributed to ferumoxytol. Three 
incidents of grade 3 toxicities were possibly attributable to ferumoxytol (one incident of 
constipation, one of neck pain and one of a rash). The most common adverse events associated 
with ferumoxytol were 20 (2.5% of total infusions) incidents of mild, transient hypertension 
and 7 (0.9% of total infusions) incidents of diarrhea. There have been no incidents of 
hypotension, syncope, unresponsiveness or cardiorespiratory arrest with these 800 
administrations of ferumoxytol. 
4.3.5 Pharmacokinetics and Drug Metabolism in Humans 
From Ferumoxytol Investigator’s brochure dated April 30, 2012: 
To evaluate pharmacokinetics of the drug, blood samples were taken at multiple time points to 
determine blood clearance by MR relaxivity measurements in the Phase 1 study. Statistical 
analysis indicated that AUC and Cmax increased with dose, but not with increasing rate of 
injection. The blood elimination half-life (t½) also increased with dose, from 9.7 to 19 hours.  
Clearance (Cl) and Volume of Distribution (Vd) decreased with dose but not with rate of 
injection.   
 
Table 2: Summary of Mean Pharmacokinetic Parameters  
(From Ferumoxytol Investigator’s brochure dated April 30, 2012:) 

 
35 
 
 
 
The serum iron, ferritin, total iron binding capacity (TIBC) and percent saturation of iron (Tsat) 
were exactly as expected for a metabolized iron oxide drug.  The profiles are shown in figure 
11. Serum iron rose markedly and in a dose-dependent manner, peaking at one day, then falling 
back to baseline by day 7.  Tsat mirrored the serum iron, rising as the serum iron rose.  Ferritin 
began to rise at day one, reflecting some metabolism of the agent, peaked at day three, and fell 
slowly back toward baseline.  Many of the serum iron values were out of normal range, 
particularly at the higher doses.  However, this laboratory test does not reflect true serum iron 
because it cannot distinguish between intact iron oxide and transferrin-bound physiological 
iron. 
 
Simple ANOVA analysis (ignoring rate of administration and sex) was performed for iron 
parameters by day and dose.  By dose, there were no differences between two weeks pre, 2 
days pre, and 1 day pre.  At 8 hours after ferumoxytol administration, serum iron and TIBC 
varied significantly by dose, and all varied significantly by dose at days 1, 2, and 3.  By day 7 
after ferumoxytol administration, only serum ferritin varied by dose.  ANOVA by time showed 
no variation for the placebo and significant variation by time for all three dose levels, as 
expected. 
 

 
36 
 
 
 
Figure 11:  Serum iron and ferritin levels at various ferumoxytol doses 
 
Temozolomide 
Rationale for Dose Selection/Regimen/Modification for temozolomide is per the product insert 
(section 14.5). 
 
4.3.6 Rationale for Endpoints 
Efficacy Endpoints 
This primary objective of this pilot study is to determine the sensitivity and specificity of 
ferumoxytol steady state imaging in distinguishing true progression in subjects who will 
receive standard of care chemoradiation with Immunotherapy (pembrolizumab) for 
glioblastoma.  
 
The secondary endpoints will provide preliminary data on safety, toxicity, and efficacy 
(progression free survival, overall survival, best response and duration of best response 
survival) in glioblastoma receiving pembrolizumab in addition to standard of care treatments. 
Data from this pilot study will be used to power a larger study. 
 
Biomarker Research End Points 
Blood Biomarker 
The number and type of systemic and tumor infiltrating T cell may suggest response to 
immunotherapy in various cancers.[39] This exploratory study will look at serum immune cell 
subtypes at various time points and correlate them with radiographic and clinical outcomes. 
This is further elaborated in section 8.3.1. 
 
Tissue Biomarker 
The type and number of tumor infiltrating immune cells including lymphocytes and 
macrophages correlate with outcomes and prognosis in solid tumors [70]. There is emmerging 
evedence that there is a correlation between the immunophenotype and PD-L1 expression to 
treatment response in a variety of solid tumors. [85-88] However, limited data is available 
regarding brain tumors. This study will explore the changes in the PDL-1 expression (before 
and after therapy with pembrolizumab) and types of tumor infiltrating immune cells with 
0
50
100
150
200
250
300
350
400
-15
-10
-5
0
5
10
Iron µg/ml
Days
Serum Iron
Placebo
1 mg/kg
2 mg/kg
4 mg/kg
0
50
100
150
200
250
300
-15
-10
-5
0
5
10
Ferritin ng/ml
Days
Serum Ferritin
Placebo
1 mg/kg
2 mg/kg
4 mg/kg

 
37 
 
radiographic and clinical outcomes in primary and metastatic brain tumors. This is further 
elaborated on in section 8.3.2. 
 
5.0 METHODOLOGY 
5.1 
Diagnosis/Condition for Entry into the Trial 
Due to the innate differences in the pathology, natural history and differences in current 
standard of care for primary and metastatic brain tumors this pilot study will have two arms: 
 
ARM 1: Metastatic brain tumors: Melanoma (closed to enrollment) 
 
ARM 2: Primary brain tumor: Glioblastoma multiforme (GBM) 
 
5.2 
Subject Inclusion Criteria 
In order to be eligible for participation in this trial, the subject must: 
1. Be willing and able to provide written informed consent/assent for the trial. 
2. Be ≥18 years of age on day of signing informed consent. 
3. Have a life expectancy of at least 6 months. 
4. Have a histologically confirmed diagnosis of: newly diagnosed glioblastoma (WHO 
Grade IV) 
5. Have ECOG performance status of 0 or 1 on stable or reducing dose of steroids for 
symptom management (not more than 8 mg of dexamethasone or equivalent per day) 
for 5 days prior to enrollment. Change in glucocorticoid dose for any purpose other 
than to modulate symptoms from an adverse event. Note: The use of physiologic doses 
(e.g., prednisone 10 mg) of corticosteroids may be approved after consultation with 
Merck & Co. Use of prophylactic corticosteroids to avoid allergic reactions (e.g. IV 
contrast dye) is permitted. 
6. At least 14 days from any major surgeries including brain biopsy before the start of 
study drug pembrolizumab. 
7. Demonstrate adequate organ function as defined in Table 3. 
8. Female subject of childbearing potential should have a negative urine or serum 
pregnancy within 72 hours prior to receiving the first dose of study medication.  If the 
urine test is positive or cannot be performed or confirmed as negative, a serum 
pregnancy test will be required. 
9. Female subjects of childbearing potential should be willing to use 2 methods of birth 
control or be surgically sterile, or abstain from heterosexual activity for the course of 
the study through 120 days after the last dose of study medication.  Subjects of 
childbearing potential are those who have not been surgically sterilized or have not 
been free from menses for > 1 year. Male subjects should agree to use an adequate 
method of contraception, including but not limited to, abstinence from heterosexual 
activity starting with the first dose of study therapy through 120 days after the last dose 
of study therapy. 
10. Subject is eligible for and agrees to receive standard of care radiation and temozolamide 
after biopsy or maximum safe surgical resection. 
 
Table 3  Adequate Organ Function Laboratory Values 
System 
Laboratory Value 

 
38 
 
Hematological 
Absolute neutrophil count (ANC) 
≥1,500 /mcL 
Platelets 
≥100,000 / mcL 
Hemoglobin 
≥9 g/dL or ≥5.6 mmol/L without transfusion or EPO dependency 
(within 7 days of assessment) 
Renal 
Serum creatinine OR 
Measured 
or 
calculateda 
creatinine 
clearance 
(GFR can also be used in place of creatinine 
or CrCl) 
≤1.5 X upper limit of normal (ULN) OR 
 
≥60 mL/min for subject with creatinine levels > 1.5 X institutional 
ULN 
Hepatic 
Serum total bilirubin 
≤ 1.5 X ULN OR 
 
Direct bilirubin ≤ ULN for subjects with total bilirubin levels > 
1.5 ULN 
AST (SGOT) and ALT (SGPT) 
≤ 2.5 X ULN  OR 
≤ 5 X ULN for subjects with liver metastases 
Albumin 
>2.5 mg/dL 
Coagulation 
International Normalized Ratio (INR) or 
Prothrombin Time (PT) 
 
Activated Partial Thromboplastin Time 
(aPTT) 
≤1.5 X ULN unless subject is receiving anticoagulant therapy 
as long as PT or PTT is within therapeutic range of intended use 
of anticoagulants 
≤1.5 X ULN unless subject is receiving anticoagulant therapy 
as long as PT or PTT is within therapeutic range of intended use 
of anticoagulants 
aCreatinine clearance should be calculated per institutional standard. 
 
5.3 
Subject Exclusion Criteria 
The subject must be excluded from participating in the trial if the subject: 
1. Has a diagnosis of immunodeficiency including Human Immunodeficiency Virus 
(HIV) (HIV 1/2 antibodies) and is not on continuous daily immunosuppressive therapy 
within 7 days prior to the first dose of trial treatment. (An exception to this is the use 
of steroids for brain edema and resulting symptoms. Subjects may receive a stable or 
reducing dose of steroids (up to 8 mg dexamethasone or equivalent for at least 5 days 
prior to signing consent) to prevent or manage cerebral edema. Subjects requiring over 
8mg of dexamethasone per day on or five days prior to signing consent are excluded). 
2. Has a known history of active TB   (Bacillus Tuberculosis) 
3. Hypersensitivity to pembrolizumab or ferumoxytol or any of their excipients. 
4. Has had a prior anti-cancer monoclonal antibody (mAb) within 4 weeks prior to study 
Day 1 or who has not recovered (i.e., ≤ Grade 1 or at baseline) from adverse events due 
to agents administered more than 4 weeks earlier. 
5. Has a known additional malignancy that is progressing or requires active treatment.  
Exceptions include basal cell carcinoma of the skin or squamous cell carcinoma of the 
skin that has undergone potentially curative therapy or in situ cervical cancer. 
6. Has active autoimmune disease that has required systemic treatment in the past 2 years 
(i.e. with use of disease modifying agents, corticosteroids or immunosuppressive 
drugs). Replacement therapy (eg thyroxine, insulin, or physiologic corticosteroid 
replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a form 
of systemic treatment. 
7. Has known history of, or any evidence of active, non-infectious pneumonitis. 
8. Has an active infection requiring systemic therapy. 

 
39 
 
9. Has a history or current evidence of any condition, therapy, or laboratory abnormality 
that might confound the results of the trial, interfere with the subject’s participation for 
the full duration of the trial, or is not in the best interest of the subject to participate, in 
the opinion of the treating investigator. 
10. Has known psychiatric or substance abuse disorders that would interfere with 
cooperation with the requirements of the trial. 
11. Is pregnant or breastfeeding, or expecting to conceive or father children within the 
projected duration of the trial, starting with the pre-screening or screening visit through 
120 days after the last dose of trial treatment. 
12. Has known active Hepatitis B (e.g., HBsAg reactive) or Hepatitis C (e.g., HCV RNA 
[qualitative] is detected). 
13. Has received a live vaccine within 30 days of planned start of study therapy. 
Note:  Seasonal influenza vaccines for injection are generally inactivated flu vaccines 
and are allowed; however intranasal influenza vaccines (e.g., Flu-Mist®) are live 
attenuated vaccines, and are not allowed. 
14. Subjects with clinically significant signs of uncal herniation, such as acute pupillary 
enlargement, rapidly developing motor changes (over hours), or rapidly decreasing 
level of consciousness, are not eligible. 
15. Subjects with known allergic or hypersensitivity reactions to parenteral iron, 
parenteral dextran, parenteral iron-dextran, or parenteral iron-polysaccharide 
preparations (Ferumoxytol Investigator’s Drug Brochure, 2009). Subjects with 
significant drug or other allergies or autoimmune diseases may be enrolled at the 
investigator’s discretion. 
16. Subjects who have a contraindication for 3T MRI: metal in their bodies (a cardiac 
pacemaker or other incompatible device), or are severely agitated. 
17. Subjects with known iron overload (genetic hemochromatosis).  In subjects with a 
family history of hemochromatosis, hemochromatosis must be ruled out prior to study 
entry with normal values of the following blood tests: Transferrin saturation (TS) test 
and Serum ferritin (SF) test. All associated costs will be paid by the study.  
18. Subject who have received ferumoxytol within 3 weeks of study entry. 
19. Subjects with three or more drug allergies from separate drug classes. 
 
5.4 
Subject Withdrawal/Discontinuation Criteria 
Subjects who complete 2 years of treatment or 35 cycles (whichever comes later) will move 
into the Follow-Up Phase and should be assessed every 12 weeks (±30 days) by clinical 
standard of care MRI scans and clinical assessment to monitor disease status for up to 1 year 
or until they progress or death.  After 1 year, the imaging and clinical assessment time point 
will occur every 6 months (± 30 days) until death. 
 
Subjects who a) attain a CR or b) complete 24 months of treatment with pembrolizumab may 
discontinue treatment with the option of restarting treatment if they meet the criteria specified 
in Section 7.11.  After discontinuing treatment following assessment of CR, these subjects 
should return to the site for a Safety Follow-up Visit (described in Section 7.8) and then 
proceed to the Follow-Up Period of the study (described in Section 7.9). 
 

 
40 
 
Subject withdrawal includes patients who wish to withdraw consent for continuing on the study 
or who were lost to followup. Additionally, subjects may be discontinued from the trial for any 
of the following reasons: 
• The subject or legal representative (such as a parent or legal guardian) withdraws 
consent. 
• Confirmed progression in brain lesions or systemic disease (confirmed by imaging or 
tissue biopsy) 
Note: A subject may be granted an exception to continue on treatment with confirmed 
radiographic progression if clinically stable or clinically improved, at the discretion of 
the treating physician. Please see Section 7.9 
• Unacceptable adverse experiences as described in Section 9.0 
• Miss two consecutive pembrolizumab treatments for any reason other than surgery.  
• Intercurrent illness that prevents further administration of treatment including clinical 
deterioration at the discretion of the PI. 
• Investigator’s decision to withdraw the subject 
• The subject has a confirmed positive serum or urine pregnancy test. If the urine test is 
positive, cannot be performed or cannot be confirmed negative, a serum pregnancy test 
will be required. 
• Noncompliance with trial treatment or procedure requirements 
• Administrative reasons 
 
The end of treatment and follow-up visit procedures are listed in the schedule of events 
(Sections 6 and 7).   
 
5.4.1 Early stopping rule 
This is a pilot study evaluating an imaging biomarker. There is sufficient data regarding the 
safety and toxicities of ferumoxytol and pembrolizumab as well as the standard of care 
therapies; safety and toxicity data reading their combination is limited. The study team 
comprising of the PI and co-investigators, reviewed the toxicity data for arm 2 on March 29, 
2019 prior to enrolling the 11th subject and there were no grade 3 or greater toxicities attributed 
to pembrolizumab, ferumoxytol, or both.  
 
A second toxicity review will be performed prior to starting enrollment of the 18 additional 
subjects provided from the closing of the melanoma arm of the study, and after every 10 
additional subjects are enrolled thereafter. The study will be terminated if more than 50% of 
the subjects enrolled at the time of the review have a grade 3 or greater toxicity that will be 1)  
definitely attributed to pembrolizumab, ferumoxytol, or both (attribution code of ‘3’); or 2) 
possibly attributed to pembrolizumab, ferumoxytol, or both (attribution code of ‘2’), unless 
they are definitely attributed (attribution code of ‘3’) to standard of care therapy. To ensure 
compliance with the early stopping rule, all adverse events will be monitored and reported 
continuously by the study team in order to stop treatment as soon as a subject experiences 
grade 3 or greater AE attributed to pembrolizumab, ferumoxytol, or both.  
 
5.4.2 Discontinuation of Study Therapy after CR 
Discontinuation of treatment may be considered for subjects who have attained a confirmed 
CR in the brain, and have been treated for at least 24 months with pembrolizumab. 

 
41 
 
 
At the discretion of the investigator, subjects who have discontinued therapy after 24 months 
and have attained and maintained a CR in the brain, but develop progressive systemic disease 
may be eligible for up to one year of additional treatment with pembrolizumab via the Second 
Course Phase, if no additional cancer treatment was administered since the last dose of 
pembrolizumab, the subject meets the safety parameters listed in the Inclusion/Exclusion 
criteria, and the trial is open.  Subjects will resume therapy at the same dose and schedule at 
the time of initial discontinuation.  Additional details are provided in Section 7.9. 
 
5.4.3 Subject Replacement Strategy 
Subjects that are unevaluable will be replaced. Subjects that are unevaluable are those who do 
not reach the first follow-up imaging time point, 4 weeks after the last day of radiation (see 
section 6.0) 
5.4.4 Clinical Criteria for Early Trial Termination 
Early trial termination will be the result of the criteria specified below: 
1. Quality or quantity of data recording is inaccurate or incomplete 
2. Poor adherence to protocol and regulatory requirements 
3. Incidence or severity of adverse drug reaction in this or other studies indicates a potential 
health hazard to subjects 
4. Plans to modify or discontinue the development of the study drug 
In the event of Merck decision to no longer supply study drug, ample notification will be 
provided so that appropriate adjustments to subject treatment can be made. 
 
 
 
 

 
42 
 
6.0 SCHEDULE OF EVENTS 
 
Screening 
visit: within 
28 days of 
first 
treatment 
Pembro 
infusion 
every 3 
weeks +15 
days 
At suspected 
radiographic 
progression (+15 
days) 
At persistent 
radiographic 
progression 
(+15 days) 
Safety follow-
up: 30 days 
(+15 days) post 
discontinuation 
of pembro 
Follow-up: 
those who 
complete 2 years 
of treatment or 
35 cycles 
Survival: follow-
up once off study8 
Informed Consent 
X 
 
 
 
 
 
 
Inclusion/Exclusion Criteria 
X 
 
 
 
 
 
 
Archival Tissue Collection (if 
available) 
X 
 
 
 
 
 
 
Standard of Care Biopsy or 
Resection of  Brain Lesion1 
 
 
 
X 
 
 
 
Demographics and Medical 
History 
X 
 
 
 
 
 
 
Medication, herbal or dietary 
supplement review 
X 
 
X 
X 
X 
X 
 
Review Adverse Events, 
include Events of Clinical 
Interest10 
 
 
X 
X 
X 
X 
 
Physical Examination2 
X 
 
 
X 
X 
X 
 
Vital Signs and Weight 
X 
 
 
X 
X 
X 
 
ECOG Performance Status 
X 
 
 
X 
X 
X 
 
CBC with Differential3 
X 
X 
 
 
X 
 
 
Comprehensive Serum 
Chemistry Panel (with LDH)3 
X 
X 
 
 
X 
 
 
Urinalysis 
X 
 
 
 
 
 
 
FT4 and TSH4 
X 
X 
 
 
X 
 
 
PT/INR, aPTT 
X 
 
 
 
X 
 
 
Pregnancy Test (urine or 
serumfemales only – see 
section 7.6) 
X 
 
 
 
 
 
 
Clinical Tumor Imaging 
X5 
 
 
 
 
X7 
 
Ferumoxytol imaging  
X6 
 
 
 
 
 
 
24 hr post study drug MRI - 
Optional 
X6 
 
 
 
 
 
 
Biomarker Collection (serum) 
Optional 
X6 
 
 
 
 
 
 
Post-study anticancer therapy 
status 
 
 
 
 
 
X 
 
Survival Status 
 
 
 
 
 
X 
X 
Telephone contact 
 
 
 
 
 
 
X8 
 

 
43 
 
1Subjects must undergo standard of care biopsy or maximal safe resection as clinically indicated prior to enrollment. 
 
2Physical exam required with every pembrolizumab infusion. 
 
3CBC and CMP (with LDH) to be done every 3 weeks while on pembrolizumab - labs must be done within 28 days before first pembrolizumab infusion, and within 72 hours of 
subsequent pembrolizumab infusions. Additional labs may be drawn at treating physician’s discretion. 
 
4FT4 and TSH with every cycle while on pembrolizumab. 
 
5Clinical standard of care MRIs are done at baseline, 4 weeks after the last day of radiation and then every 9 weeks (see special instructions below for evaluating persistent 
radiographic progression). Clinical MRIs may be done more often at physician’s discretion. 
 
6Ferumoxytol steady state MRIs (within 7 days of clinical standard of care MRIs) are done baseline, 4 weeks after the last day of radiation, anytime there is suspected radiographic 
progression and 4 weeks after suspected radiographic progression (all timepoints +15 days). Serum biomarkers will be obtained +15days of ferumoxytol MRI scan. 
 
7 Follow-up after completing 2 years of treatment or 35 cycles (whichever comes later): according to standard of care. 
 
8 Survival follow-up once off study: Telephone contact every 12 weeks (+30 days) to assess for survival status until death, withdrawal of consent, the end of the study, or loss to 
follow-up, whichever occurs first. 
 
 
10Adverse event review will be recorded in Epic continuously while on study. A separate Epic note will be done with each course. All AEs are assessed for attribution to 
pembrolizumab, ferumoxytol, and standard of care therapy  
Trial treatment with pembrolizumab will start on the first day of standard of care radiation (+15 days) and thereafter every 3 weeks (+15 days) (dosing delays of up to 7 days are 
permitted at physician discretion for medical / surgical events or logistical reasons) for up to 2 years or 35 cycles or confirmed radiographic progression, whichever occurs first.  
Dosing interruptions (missing a dose) are permitted in the case of medical / surgical events or logistical reasons not related to study therapy (e.g., elective surgery, unrelated 
medical events, subject vacation, and/or holidays), not to exceed two consecutive doses or a maximum of 9 weeks. 
 
Imaging instructions for evaluating persistent radiographic progression: if there is suspected progression, subjects undergo a ferumoxytol steady state MRI and continue on 
pembrolizumab for one more cycle (total of 4 weeks). At the 4 week point, clinical standard of care and ferumoxytol MRIs will be repeated to confirm persistent radiographic 
progression. If the 4 week scan confirms progression, then pembrolizumab is discontinued and subject is evaluated for surgery. If histopathology confirms pseudoprogression or is 
inconclusive, the subject will continue on pembrolizumab every 3 weeks until further radiographic progression is suspected. If histopathology confirms progression, the subject 
will be removed from the study. If the subject is not a surgical candidate, they will be taken off study and move into the survival follow up stage. 
 
 

 
44 
 
7.0 TREATMENT PLAN AND PROCEDURES 
7.1 
Participant Screening and Enrollment 
In order to participate in this study, signed informed consent must be obtained from the 
participant. The current Institutional Review Board (IRB) approved informed consent must be 
signed and dated by each participant prior to undergoing any study procedures or before any 
prohibited medications are withheld from the participant in order to participate in this study.  
 
7.2 
Participant Registration 
Participants will be required to give written informed consent to participate in the study before 
any screening tests or evaluations are conducted that are not part of standard care. Registration 
from all consented participants must be entered into the OHSU electronic Clinical Research 
Management System (eCRIS). At a minimum, registration of OHSU participants will include: 
• Unique study number 
• A completed review of eligibility criteria signed by the Principle Investigator 
• Signed copies of the most recently IRB-approved, informed consent form and HIPAA 
authorization 
 
The Schedule of Events - Section 6.0 summarizes the trial procedures to be performed at each 
visit.  Individual trial procedures are described in detail below.  It may be necessary to perform 
these procedures at unscheduled time points if deemed clinically necessary by the investigator. 
 
Furthermore, additional evaluations/testing may be deemed necessary by the Sponsor and/or 
Merck for reasons related to subject safety. In some cases, such evaluation/testing may be 
potentially sensitive in nature (e.g., HIV, Hepatitis C, etc.), and thus local regulations may 
require that additional informed consent be obtained from the subject.  In these cases, such 
evaluations/testing will be performed in accordance with those regulations. 
 
7.3 
Trial Treatments 
The treatment to be used in this trial is outlined below in Table 4 
 
Table 4  Trial Treatment 
Drug 
Dose/Potency Dose 
Frequency  
Route of 
Administration 
Regimen/Treatment 
Period  
Use 
Investigational Agents 
Pembrolizumab 200mg 
Every 3 
weeks 
(+15days) 
(starting on 
first day of 
standard of 
care therapy 
(+ 15 days) 
IV infusion 
Day 1 of each 3 
week cycle 
Experimental 
Ferumoxytol 
7mg/kg 
(maximum 
dose not to 
exceed 
510mg) 
Baseline, 4 
weeks post 
radiation, 
anytime 
there is 
IV infusion 
Baseline, 4 weeks 
post radiation, 
anytime there is 
suspected 
radiographic 
Experimental 

 
45 
 
Drug 
Dose/Potency Dose 
Frequency  
Route of 
Administration 
Regimen/Treatment 
Period  
Use 
suspected 
radiographic 
progression 
and 4 weeks 
after 
suspected 
radiographic 
progression 
(all +15 
days).  
 
progression and 4 
weeks after 
suspected 
radiographic 
progression (all +15 
days).  
 
Standard of Care Treatments 
Arm 1 only 
Stereotactic 
radiosurgery 
18-35Gy  
See section 
7.4 
See section 7.4 
See section 7.4 
Standard of 
care 
Arm 2 only 
Radiation 
Up to 60Gy 
Daily 
(Monday-
Friday) for 
6 weeks 
See section 7.4 
6 weeks 
Standard of 
care 
Concurrent 
temozolomide 
75 mg/m2 
Daily 
(Monday-
Sunday) 
during 
radiation 
Oral 
6 weeks 
Standard of 
care 
Adjuvant 
temozolomide 
150-200 
mg/m2 
First 5 days 
of a 4 week 
cycle  
Oral 
At least 6 months 
Standard of 
care 
 
Timing of Dose Administration 
Pembrolizumab: Trial drug treatment should be administered every 3 weeks. All trial 
treatments will be administered on an outpatient basis. Dosing delays of up to 7 days are 
permitted at physician discretion for medical / surgical events or logistical reasons. Dosing 
interruptions (missing a dose) are permitted in the case of medical / surgical events or logistical 
reasons not related to study therapy (e.g., elective surgery, unrelated medical events, subject 
vacation, and/or holidays), not to exceed two consecutive doses or a maximum of 9 weeks. 
The reason for interruption will be documented in the subject’s study record. Pembrolizumab 
will not be administered less than 14 days after any major surgeries including brain biopsy. 
 
Pembrolizumab 200mg will be administered every 3 weeks as per institutional guidelines.  The 
expiration of the reconstituted pembrolizumab is 4 hours at room temperature and 20 hours 
refrigerated.  
 
The Pharmacy Manual contains specific instructions for the preparation of the Pembrolizumab 
infusion fluid and administration of infusion solution. 
 

 
46 
 
Ferumoxytol (only for study MRIs): The total dose of ferumoxytol will be 7mg/kg (not 
exceeding 510mg total) per imaging session. The ferumoxytol will be mixed with normal 
saline 1:1 solution to dilute to 15mg/ml.  1 mg/Kg IV will be  injected at the start of the 7th 
dynamic cycle during the DSC acquisition at a flow rate of 3ml/s followed by 20ml saline 
flush. The rest of the ferumoxytol will be given as IV injections at a low flow rate (.1ml/s) 
followed by 20mL saline flush. The flow rates may be adjusted at the physician’s discretion. 
 
Vitals monitoring for ferumoxytol MRIs: Blood pressure and pulse will be taken at the start of 
MRI (+ 5 minutes), after each ferumoxytol injection (+ 5 minutes), and again 30 minutes (+ 5 
minutes) after the first injection of ferumoxytol. 
 
7.4 
Study procedures narrative 
Due to the innate differences in the pathology, natural history and differences in current 
standard of care for primary and metastatic brain tumors this pilot study will have two arms: 
 
ARM 1: Metastatic brain tumors - Melanoma 
 
ARM 2: Primary brain tumor - Glioblastoma multiforme (GBM) 
 
All subjects will receive standard of care treatment for their respective arms as described in 
section 7.6. 
 
All subjects will receive pembrolizumab (200 mg IV every 3 weeks) starting on the first day of 
radiation until persistent radiographic progression is confirmed, in addition to standard of care 
for their respective arms. Clinical MRI scans will be performed to assess response to therapy. 
Clinical standard of care MRIs are done at baseline, 4 weeks after the last day of radiation and 
then every 9 weeks thereafter until suspected radiographic progression. Early follow up clinical 
standard of care MRI (and ferumoxytol steady state MRI, see below) will be performed 4 
weeks from the date of MRI showing suspected radiographic progression to confirm persistent 
radiographic progression (all timepoints +5 days). Patients with imaging evidence of suspected 
radiographic progression may continue with one additional cycle of pembrolizumab. The 
decision regarding continuation of pembrolizumab will be made by the principle investigator 
based on clinical findings that include (1) stable ECOG performance status with no more than 
8mg of dexamethasone (or equivalent) a day; (2) absence of new or worsening symptoms not 
managed with steroids; and (3) absence of progressive tumor at critical anatomical sites (e.g., 
spinal cord compression) requiring urgent alternative medical intervention. 
 
Additional ferumoxytol steady state MRIs will be done at baseline, 4 weeks after the last day 
of radiation, at suspected radiographic progression and within 4 weeks from suspected 
radiographic progression to confirm persistent radiographic progression (all timepoints +5 
days). During this follow up period, subjects will be followed with a clinical exam weekly to 
monitor for clinical stability. 
  
When persistent radiographic progression is confirmed, subjects will be evaluated for a 
craniotomy with intent to complete resection and/or biopsy of the enhancing lesion, if this is 
thought to be the clinical standard of care. 

 
47 
 
 
When there is radiologic progression after radiation, current standard of care includes repeat 
craniotomy to confirm true vs pseudoprogression. Biopsy tissue obtained from surgery at 
persistent radiographic progression will be evaluated by the pathologists at OHSU. The 
pathologist will determine if the tissue is consistent with progression or pseudoprogression, 
where progression is defined as presence of viable metastatic carcinoma in the biopsy tissue 
and absence of tumor cell is assumed to reflect pseudoprogression. If histopathology confirms 
pseudoprogression the subject will continue on pembrolizumab every 3 weeks until further 
radiographic progression is suspected. If histopathology confirms progression, the subject will 
be removed from the study, followed clinically with serial clinical stand of care MRIs every 3 
months for up to a year and then every 6 months until death or lost to follow-up. 
 
Standard of care surgery or biopsy is performed only if 1) the lesion is deemed easily accessible 
2) surgery is not expected to worsen neurological outcomes and 3) it is in the best clinical 
interest of the patient. The decision regarding surgery will be consensus based and when 
possible, will be made after each individual case has been presented at the OHSU multi-
disciplinary brain tumor board. If a subject is not a surgical candidate, or is unwilling to 
undergo surgery, they will be taken off study. They will, however, be eligible for continuation 
of pembrolizumab, at the physician’s discretion, at the same dose and frequency, if clinical 
benefit is noted. They will be followed clinically with serial clinical standard of care MRI scans 
as described in section 7.11. 
 
In subjects where the lesion remains unchanged or regresses in volume at 4 weeks (+5 days) 
after the date of suspected radiographic progression, pembrolizumab will be continued until 
further persistent radiographic progression is confirmed. 
 
All subjects will be followed with clinical examination and clinical standard of care MRI scans 
until death or lost to follow up. Subjects will be treated for up to 2 years, toxicity, or 
progression whichever comes first.  Dose reductions/discontinuations for pembrolizumab will 
be as per Merck guidelines. 
 
Subjects can restart pembrolizumab within 2 weeks after surgery.  If the subject has a surgical 
complication that will prevent them from starting pembrolizumab within 2 weeks, the PI will 
discuss these cases with Merck & Co on a case by case basis. However, if pathology suggests 
pseudoprogression, pembrolizumab will be restarted 30 days (+ 5 days) after surgery.  
 
7.5 
Informed Consent 
The Investigator must obtain documented consent from each potential subject prior to 
participating in a clinical trial. 
 
Consent must be documented by the subject’s dated signature on a consent form along with 
the dated signature of the person conducting the consent discussion. 
 
A copy of the signed and dated consent form should be given to the subject before participation 
in the trial. 
 

 
48 
 
The initial informed consent form, any subsequent revised written informed consent form and 
any written information provided to the subject must receive the IRB/ERC’s 
approval/favorable opinion in advance of use.  The subject should be informed in a timely 
manner if new information becomes available that may be relevant to the subject’s willingness 
to continue participation in the trial.  The communication of this information will be provided 
and documented via a revised consent form or addendum to the original consent form that 
captures the subject’s dated signature. 
 
Specifics about a trial and the trial population will be added to the consent form template at 
the protocol level. 
 
The informed consent will adhere to IRB/ERC requirements, applicable laws and regulations 
and Sponsor requirements. 
 
7.6 
Trial Procedures 
See the Schedule of Events for when tests should be completed. 
 
Clinical procedures: 
• Demographics 
• Medical history 
• Prior medication review 
o The investigator or qualified designee will review prior medication and herbal and 
dietary supplement use, including any protocol-specified washout requirement, and 
record prior medication taken by the subject within 28 days before starting the trial.  
Treatment for the disease for which the subject has enrolled in this study will be 
recorded separately and not listed as a prior medication. 
o The investigator or qualified designee will record medication, if any, taken by the 
subject during the trial.  All medications related to reportable SAEs and ECIs 
should be recorded. 
o Subjects will be asked to stop all nonprescription herbal supplements and over the 
counter medication. 
• Full physical examination 
• Vital signs 
o temperature, pulse, respiratory rate, height, weight and blood pressure.  Height 
will be measured at screening only. 
• ECOG performance status (Appendix) 
• Archival tissue collection: 
o If available, any tumor biopsy tissue (lung, mediastinal, or brain) that was 
obtained prior to screening for the study will be requested and sent to the 
Merck-designated Contract Research Organization (CRO) QualTek Molecular 
Laboratories for PD-L1 biomarker assay. 
• Biopsy or resection of metastatic brain lesion 
o When clinically indicated, a biopsy or resection will be done of the brain 
lesion(s) 1) prior to enrollment and SRS, and 2) at the time of persistent 
radiographic progression. Any tumor biopsy tissue will be sent to the Merck-

 
49 
 
designated Contract Research Organization (CRO) QualTek Molecular 
Laboratories for PD-L1 biomarker assay. 
o At persistent radiographic progression, a repeat biopsy or resection is 
considered standard of care to distinguish true vs pseudoprogression.  
• Standard of care therapy: 
o Arm 1: All patients will receive standard of care stereotactic radiosurgery in 1-5 
fractions, at the discretion of the treating radiation oncologist. If all lesions cannot 
be treated on the same day, all lesions MUST be treated ≤14 days of treatment of 
the first lesion. Gamma knife or X-rays with nominal energy of 4 megavoltage 
(MV) or greater for accelerator-based treatments, including isocentric conical 
collimators, mini-multi-leaf (5mm or less) technology or linear accelerators 
mounted on robotic arms will be used to deliver the target dose . 
o Target Volume: The volumes shall be defined by a planning MRI brain 
scan, with the patient in the treatment position.  The target volume should 
include the enhancement seen on planning MRI with 0-1 mm margin.  The 
maximal cross-sectional diameter must be < 3.0 cm for a lesion treated with 
a single fraction. 
o Target Dose: The dose should be prescribed to the highest isodose line 
encompassing the 90-95% target volume.  General dose guidelines are as 
follows 
o Lesion diameter < 1cm – 20-22 Gy in 1 fraction 
o Lesion diameter 1-2 cm – 18-20 Gy in 1 fraction 
o Lesion diameter 2-3 cm – 18 Gy in 1 fraction, or 27 Gy in 3 fraction 
or 30-35 Gy in 5 fractions 
o Lesion diameter 3-5cm – 30 – 35 Gy in 5 fractions 
o Up to 8 of dexamethasone can be administered on the day of single fraction 
SRS, at the discretion of the treating physician. 
o Arm 2:  
o All patients in this arm will be treated with standard of care radiotherapy 
consisting of fractionated focal irradiation to gross tumor volume 
(GTV) plus a up to 3-cm margin at a dose of up to 2-Gy per fraction 
given once daily five days per week (Monday through Friday) over a 
period of six weeks, for a total dose of up to 60 Gy.  
o Additionally, standard of care temozolamide 75 mg/m2 once daily 
(Monday through Sunday) over the 6 weeks duration of radiation. After 
a 4-week break, subjects will then receive up to six cycles of adjuvant 
temozolomide according to the standard 5-day schedule every 28 days 
(150 mg/m2 for the first cycle and then increased to 200 mg/m2 
beginning with the second cycle, as long as there were no hematologic 
toxic effects as per Stupp et al 2005 [80]. Dose modifications for 
temozolomide are described in section 7.13.  
 
o Radiation therapy to an additional symptomatic solitary lesion or to the brain 
may be allowed at the investigator’s discretion at any time during the study if :  
• they fulfill other criteria to remain in the study and  

 
50 
 
• this lesion has remained stable or shows radiographic response 
compared to baseline. 
• this additional lesion was not in the initial radiation field.  
 
Subjects may continue with pembrolizumab even if radiation or chemotherapy is discontinued, 
at the discretion of the PI.  
 
Additionally, subjects may receive prophylaxis against Pneumocystis carinii pneumonia, 
consisting of either inhaled pentamidine or oral trimethoprim–sulfamethoxazole, at the 
physician’s discretion [89].  
 
Subject may also provide consent/assent for future correlative research (optional).  Subjects 
may participate in the main trial without participating in future correlative research. 
 
Lab tests (see Table 5): 
• CBC with differential 
• Comprehensive serum chemistry panel 
• Urinalysis 
• FT4, TSH 
• PT/INR 
• aPTT 
• Pregnancy test (urine or serum) (women). If the urine test is positive, cannot be 
performed or cannot be confirmed as negative, a serum pregnancy test will be required. 
• Serum biomarker assay (see Section 8.3.1) 
 

 
51 
 
Table 5 Laboratory Tests 
Hematology 
Chemistry 
Urinalysis 
Other 
Hematocrit 
Albumin 
Blood 
Serum β-human chorionic gonadotropin† 
Hemoglobin 
Alkaline phosphatase 
Glucose 
(β-hCG)† 
Platelet count 
Alanine aminotransferase (ALT) 
Protein 
PT (INR) 
WBC (total and differential) 
Aspartate aminotransferase (AST) 
Specific gravity 
aPTT 
Red Blood Cell Count 
Lactate dehydrogenase (LDH) 
Microscopic exam (If abnormal) 
Free tyroxine (T4) 
Absolute Neutrophil Count 
Carbon Dioxide ‡ 
results are noted 
Thyroid stimulating hormone (TSH) 
Absolute Lymphocyte Count 
(CO2 or biocarbonate) 
Urine pregnancy test † 
 
 
Calcium 
 
Blood for correlative studies 
 
Chloride 
 
 
 
Glucose 
 
 
 
Potassium 
 
 
 
Sodium 
 
 
 
Total Bilirubin 
 
 
 
Direct Bilirubin (If total bilirubin is 
elevated above the upper limit of 
normal)Total Bilirubin 
 
 
 
Total protein  
 
 
 
 
 
 
 
 
 
 
 

 
52 
 
Laboratory tests for screening or entry into the Second Course Phase should be performed 
within 10 days prior to the first dose of treatment.  After Cycle 1, pre-dose laboratory 
procedures can be conducted up to 72 hours prior to dosing.  Results must be reviewed by the 
investigator or qualified designee and found to be acceptable prior to each dose of trial 
treatment. 
 
Imaging (all timepoints +15 days) 
Standard of care clinical brain MRI: Clinical MRIs are done at baseline, 4 weeks after the 
last day of radiation and then every 9 weeks (see special instructions below for evaluating 
persistent radiographic progression). Gadolinium is the preferred contrast agent, when subject 
qualifies (per institutional policy, see section 8.2.2) for gadolinium infusion, but is not 
required. 
 
Ferumoxtyol MR (FeMRI): ferumoxytol steady state MRIs of the brain are done baseline, 4 
weeks after the last day of radiation, anytime there is suspected radiographic progression and 
4 weeks after suspected radiographic progression. Additional optional MR imaging of 
systemic lesions for subjects in Arm 1 may be performed in the same setting and time points 
as the brain imaging. Details are explained in section 8.2.3.  
 
Evaluation of systemic disease burden (only for Arm 1): A standard of care PET/CT or CT 
abdomen, chest and pelvis with contrast will be obtained within 3 months of enrollment and at 
least every 6 months thereafter. This is considered standard of care for patients with systemic 
cancer.  Stable systemic disease burden should be demonstrated at enrollment and for 
continuation of study drug. 
 
Imaging Schedule (all timepoints +15 days) 
Arm 1: All patients will be scanned with clinical MRI at baseline prior to radiation, 4 weeks 
after the last day of radiation and there after every 9 weeks. Ferumoxytol steady state MRI 
(FeMRI) will be performed in the same sitting at baseline and 4 weeks after the last day of 
radiation. Thereafter, FeMRI may be performed independent of the clinical MRI if there is 
suspected radiographic progression or to confirm radiographic progression. Patients enrolled 
in ARM 1 may be concomitantly enrolled into additional brain tumor imaging studies 
conducted at OHSU. 
 
Arm 2: All patients will be scanned with clinical MRI at baseline prior to radiation, 4 weeks 
after the last day of radiation and there after every 9 weeks. FeMRI will be performed in the 
same sitting at baseline and 4 weeks after the last day of radiation.  Thereafter, FeMRI may be 
performed independent of the clinical MRI if there is suspected radiographic progression or to 
confirm radiographic progression. If there is suspected progression, subjects undergo a 
ferumoxytol steady state MRI and continue on pembrolizumab for one more cycle (total of 4 
weeks). At the 4 week point, clinical standard of care and ferumoxytol MRIs will be repeated 
to confirm persistent radiographic progression. If the 4 week scan confirms progression, then 
pembrolizumab is discontinued and subject is evaluated for surgery. If histopathology confirms 
pseudoprogression or is inconclusive, the subject will continue on pembrolizumab every 3 
weeks until further radiographic progression is suspected. If histopathology confirms 
progression, the subject will be removed from the study. 

 
53 
 
 
Contrast agents dosing and administration 
Clinical Standard of Care MRI: Gadoteridol enhanced MRI will be used per institutional 
guidelines (see section 8.2.2). In subjects that are already enrolled and have underwent at least 
one gadolinium enhanced MRI, but do not qualify to get Gadolinium at subsequent imaging 
time points, non-contrast enhanced MRI can be used as clinical MRI. 
 
Dosing of Gadoteridol:  After acquiring precontrast images, gadoteridol (Prohance®, Bracco 
Pharm) will be injected using a power injector. An IV bolus of 0.1 mmol/kg at a flow rate of 
up to 3 mL/s will be administered, followed by a saline flush during the first DSC sequence. 
The appropriate volume of gadoteridol is based on the subject’s weight (0.2 ml/kg gadoteridol 
= 0.1 mmol/Kg) followed by a 20ml saline flush. 
 
Ferumoxytol Imaging 
Ferumoxytol imaging consists of two consecutive days of imaging (early and delayed) and will 
be performed only at time points described in the study schema. 
Early intravascular phase scan ferumoxytol imaging 
Dosing of ferumoxytol: The total dose of ferumoxytol (AMAG Pharmaceuticals, 
Inc., Cambridge MA) will be 7mg/kg (not exceeding 510mg total).  The 
ferumoxytol will be mixed with normal saline 1:1 solution to dilute to 15mg/ml.  1 
mg/Kg IV will be  injected at the start of the 7th dynamic cycle during the DSC 
acquisition at a flow rate of 3ml/s followed by 20ml saline flush. The rest of the 
ferumoxytol will be given as IV injections at a low flow rate (1ml/s) followed by 
20mg saline flush. The flow rates may be adjusted at the physician’s discretion. 
 
Delayed (18-72h) parenchymal phase ferumoxytol scan - Optional 
No contrast agent will be given during this MRI. This scan is optional. Every effort 
will be made to schedule the scan as close to 24 hours after ferumoxytol as possible. 
 
Image processing 
Image processing will be done at OHSU.  SS-CBV maps will be created using the high 
resolution T2*w scans before and after contrast agent and ΔR2* maps will be created using 
the formula ΔR2*=ln(SIpre/SIpost)/TE, in which SIpre and SIpost indicate the signal intensities 
pre- and post ferumoxytol, and TE is the echo time. When gadolinium is given, DSC-CBV 
maps from gadoteridol DSC will be created using a mathematical leakage correction method 
in NordicICE (Nordic Neurolab, Bergen, Norway) an FDA approved perfusion MRI software. 
The coregistration and overlay of CBV maps on T1-w MPRAGE will be done using NordicICE 
as well [90, 91]. The clinical MR sequences, such as T1 weighted scans with and without 
gadoteridol, and T2 weighted pre contrast scans will also be read. Images will be read by 2 
radiologists. The radiologists will be blinded to the type of CBV maps (SS and DSC) and 
subject information 
 
Adverse Event Monitoring 
The investigator or qualified designee will assess each subject to evaluate for potential new or 
worsening AEs as specified in the Schedule of Events and more frequently if clinically 
indicated.  Adverse experiences will be graded and recorded throughout the study and during 

 
54 
 
the follow-up period according to NCI CTCAE Version 4.0.  Toxicities will be characterized 
in terms regarding seriousness, causality, toxicity grading, and action taken with regard to trial 
treatment. All AEs will be attributed to pembrolizumab or ferumoxytol separately. 
 
For subjects receiving treatment with pembrolizumab all AEs of unknown etiology associated 
with pembrolizumab exposure should be evaluated to determine if it is possibly an event of 
clinical interest (ECI) of a potentially immunologic etiology (termed immune-related adverse 
events, or irAEs); see the separate ECI guidance document regarding the identification, 
evaluation and management of potential irAEs. 
 
Please refer to Section 9 for detailed information regarding the assessment and recording of 
AEs. 
 
7.7 
Post-study anticancer therapy status 
The investigator or qualified designee will review all new anti-neoplastic therapy initiated after 
the last dose of trial treatment.  If a subject initiates a new anti-cancer therapy within 30 days 
after the last dose of trial treatment, the 30 day Safety Follow-up visit must occur before the 
first dose of the new therapy.  Once new anti-cancer therapy has been initiated the subject will 
move into survival follow-up. 
 
7.8 
Safety Follow-Up Visit: 30 days (+15 days) post discontinuation 
The mandatory Safety Follow-Up Visit should be conducted approximately 30 days after the 
last dose of trial treatment or before the initiation of a new anti-cancer treatment, whichever 
comes first.  All AEs that occur prior to the Safety Follow-Up Visit should be recorded.  
Subjects with an AE of Grade > 1 attributed to pembrolizumab or ferumoxytol will be followed 
until the resolution of the AE to Grade 0-1 or until the beginning of a new anti-neoplastic 
therapy, whichever occurs first.  SAEs that occur within 90 days of the end of treatment or 
before initiation of a new anti-cancer treatment should also be followed and recorded.  Subjects 
who are eligible for retreatment with pembrolizumab (as described in Section 7.9) may have 
up to two safety follow-up visits, one after the Treatment Period and one after the Second 
Course Phase. 
 
7.9 
Follow-up 
Subjects who complete 2 years of treatment or 35 cycles (whichever comes later) will move 
into the Follow-Up Phase and should be assessed every 12 weeks (±30 days) by clinical 
standard of care MRI scans and clinical assessment to monitor disease status for up to 1 year 
or until they progress or death.  After 1 year, the imaging and clinical assessment time point 
will occur every 6 months (± 30 days) until death. 
 
7.10 Survival Follow-up when off study 
Once a subject is taken of study for any reason, the subject moves into the survival follow-up 
phase. Survival data will be collected from the medical record when available. When possible, 
the patient will be contacted by telephone approximately every 12 weeks to assess for survival 
status until death, withdrawal of consent, or the end of the study, whichever occurs first.  
 

 
55 
 
7.11 Second Course Phase (Retreatment Period) 
Subjects who stop pembrolizumab with CR in the brain and systemically may be eligible for 
up to one year of additional pembrolizumab therapy if they progress systemically, but maintain 
a CR in the brain.  This retreatment is termed the Second Course Phase of this study and is 
only available if the study remains open and the subject meets the following conditions: 
Either 
o Stopped initial treatment with pembrolizumab after attaining an investigator-
determined confirmed CR, and 
▪ Was treated for at least 24 weeks with pembrolizumab before discontinuing 
therapy 
▪ Received at least two treatments with pembrolizumab beyond the date when 
the initial CR was declared 
OR 
o Had CR in the brain and systemically and stopped pembrolizumab treatment after 
24 months of study therapy for reasons other than disease progression or 
intolerability 
AND 
• Experienced an investigator-determined confirmed radiographic disease progression 
after stopping their initial treatment with pembrolizumab 
• Did not receive any anti-cancer treatment since the last dose of pembrolizumab 
• Has a performance status of 0 or 1 on the ECOG Performance Scale 
• Demonstrates adequate organ function as detailed in Section 5.2 
• Female subject of childbearing potential should have a negative serum or urine 
pregnancy test within 72 hours prior to receiving retreatment with study medication. 
• Female subject of childbearing potential should be willing to use 2 methods of birth 
control or be surgically sterile, or abstain from heterosexual activity for the course of 
the study through 120 days after the last dose of study medication. Subjects of child 
bearing potential are those who have not been surgically sterilized or have been free 
from menses for > 1 year. 
• Male subject should agree to use an adequate method of contraception including but 
not limited to abstinence from heterosexual activity starting with the first dose of study 
therapy through 120 days after the last dose of study therapy.  
• Does not have a history or current evidence of any condition, therapy, or laboratory 
abnormality that might interfere with the subject’s participation for the full duration of 
the trial or is not in the best interest of the subject to participate, in the opinion of the 
treating investigator. 
 
Subjects who restart treatment will be retreated at the same dose and dose interval as when 
they last received pembrolizumab.  Treatment will be administered for up to one additional 
year. 
 
Visit requirements are outlined in Section 6.0 – Schedule of Events. 
 

 
56 
 
7.12 Dose modification and toxicity management for immune-related AEs associated 
with pembrolizumab 
Pembrolizumab 
AEs associated with pembrolizumab exposure may represent an immunologic etiology. 
These immune-related AEs (irAEs) may occur shortly after the first dose or several months 
after the last dose of pembrolizumab treatment and may affect more than on body system 
simultaneously. Therefore, early recognition and initiation of treatment is critical to reduce 
complications.  Based on existing clinical trial data, most irAEs were reversible and could be 
managed with interruptions of pembrolizumab, administration of corticosteroids and/or other 
supportive care. For suspected irAEs, ensure adequate evaluation to confirm etiology or 
exclude other causes. Additional procedures or tests such as bronchoscopy, endoscopy, skin 
biopsy may be included as part of the evaluation. Based on the severity of irAEs, withhold or 
permanently discontinue pembrolizumab and administer corticosteroids. Dose modification 
and toxicity management guidelines for irAEs associated with pembrolizumab are provided 
in Table 6.  
 
Table 6 Dose Modification and Toxicity Management Guidelines for Immune-related 
AEs Associated with Pembrolizumab 
 
General instructions: 
1. Corticosteroid taper should be initiated upon AE improving to Grade 1 or less and continue to taper over at least 4 weeks. 
2. For situations where pembrolizumab has been withheld, pembrolizumab can be resumed after AE has been reduced to Grade 1 
or 0 and corticosteroid has been tapered. Pembrolizumab should be permanently discontinued if AE does not resolve within 12 
weeks of last dose or corticosteroids cannot be reduced to ≤10 mg prednisone or equivalent per day within 12 weeks.  
3. For severe and life-threatening irAEs, IV corticosteroid should be initiated first followed by oral steroid. Other 
immunosuppressive treatment should be initiated if irAEs cannot be controlled by corticosteroids. 
 
Immune-related 
AEs 
Toxicity grade or 
conditions 
(CTCAEv4.0) 
Action taken to 
pembrolizumab 
irAE management with 
corticosteroid and/or other 
therapies  
Monitor and follow-up  
Pneumonitis  
Grade 2 
Withhold  
• Administer corticosteroids (initial 
dose of 1-2 mg/kg prednisone or 
equivalent) followed by taper 
 
• 
Monitor participants for 
signs and symptoms of 
pneumonitis 
• 
Evaluate participants with 
suspected pneumonitis 
with radiographic imaging 
and initiate corticosteroid 
treatment 
• 
Add prophylactic 
antibiotics for 
opportunistic infections 
Grade 3 or 4, or 
recurrent Grade 2 
Permanently 
discontinue 
Diarrhea / Colitis  Grade 2 or 3 
Withhold 
• Administer corticosteroids (initial 
dose of 1-2 mg/kg prednisone or 
equivalent) followed by taper 
 
• 
Monitor participants for 
signs and symptoms of 
enterocolitis (ie, diarrhea, 
abdominal pain, blood or 
mucus in stool with or 
without fever) and of bowel 

 
57 
 
Grade 4 
Permanently 
discontinue 
perforation (ie, peritoneal 
signs and ileus). 
• 
Participants with ≥ Grade 2 
diarrhea suspecting colitis 
should consider GI 
consultation and 
performing endoscopy to 
rule out colitis.  
• 
Participants with 
diarrhea/colitis should be 
advised to drink liberal 
quantities of clear fluids.  If 
sufficient oral fluid intake 
is not feasible, fluid and 
electrolytes should be 
substituted via IV infusion. 
AST / ALT 
elevation or 
Increased 
bilirubin 
Grade 2 
Withhold 
• Administer corticosteroids (initial 
dose of 0.5- 1 mg/kg prednisone or 
equivalent) followed by taper 
• 
Monitor with liver function 
tests (consider weekly or 
more frequently until liver 
enzyme value returned to 
baseline or is stable 
Grade 3 or 4  
Permanently 
discontinue 
• Administer corticosteroids (initial 
dose of 1-2 mg/kg prednisone or 
equivalent) followed by taper 
Type 1 diabetes 
mellitus (T1DM) 
or 
Hyperglycemia 
 
Newly onset 
T1DM or  
Grade 3 or 4 
hyperglycemia 
associated with 
evidence of -cell 
failure 
Withhold 
• Initiate insulin replacement 
therapy for participants with 
T1DM  
• Administer anti-hyperglycemic in 
participants with hyperglycemia  
 
• 
Monitor participants for 
hyperglycemia or other 
signs and symptoms of 
diabetes. 
Hypophysitis 
Grade 2 
Withhold 
• Administer corticosteroids and 
initiate hormonal replacements as 
clinically indicated.   
 
• 
Monitor for signs and 
symptoms of hypophysitis 
(including hypopituitarism 
and adrenal insufficiency)  
Grade 3 or 4  
Withhold or 
permanently 
discontinue1  
Hyperthyroidism  
Grade 2 
Continue  
• Treat with non-selective beta-
blockers (eg, propranolol) or 
thionamides as appropriate  
• 
Monitor for signs and 
symptoms of thyroid 
disorders.  
 
Grade 3 or 4  
Withhold or  
permanently 
discontinue1 
Hypothyroidism 
Grade 2-4 
Continue  
• Initiate thyroid replacement 
hormones (eg, levothyroxine or 
liothyroinine) per standard of care 
• 
Monitor for signs and 
symptoms of thyroid 
disorders.  
 
Nephritis and 
Renal 
dysfunction 
Grade 2 
Withhold  
• Administer corticosteroids 
(prednisone 1-2 mg/kg or 
equivalent) followed by taper. 
• 
Monitor changes of renal 
function 
 
Grade 3 or 4  
Permanently 
discontinue 
Myocarditis 
Grade 1 or 2 
Withhold 
• Based on severity of AE 
administer corticosteroids 
• 
Ensure adequate evaluation 
to confirm etiology and/or 
exclude other causes 
 
Grade 3 or 4 
Permanently 
discontinue 

 
58 
 
All other 
immune-related 
AEs 
Intolerable/ 
persistent Grade 2 
Withhold 
• Based on type and severity of AE 
administer corticosteroids  
• 
Ensure adequate evaluation 
to confirm etiology and/or 
exclude other causes 
 
Grade 3 
Withhold or 
discontinue based 
on the type of 
event.  Events that 
require 
discontinuation 
include and not 
limited to:  
Gullain-Barre 
Syndrome, 
encephalitis 
Grade 4 or 
recurrent Grade 3  
Permanently 
discontinue 
1. Withhold or permanently discontinue pembrolizumab is at the discretion of the investigator or treating physician.   
NOTE:  
For participants with Grade 3 or 4 immune-related endocrinopathy where withhold of pembrolizumab is required, pembrolizumab 
may be resumed when AE resolves to ≤ Grade 2 and is controlled with hormonal replacement therapy or achieved metabolic control 
(in case of T1DM).   
 
 
 
Table 7 below shows treatment guidelines for subjects who experience an infusion reaction 
associated with administration of pembrolizumab.  
 
 
 
 
 
 
 
 

 
59 
 
Table 7: Infusion Reaction Treatment Guidelines 
NCI CTCAE Grade 
Treatment 
Premedication at 
Subsequent Dosing 
Grade 1 
Mild reaction; infusion 
interruption not 
indicated; intervention 
not indicated 
Increase monitoring of vital signs as medically 
indicated until the subject is deemed medically 
stable in the opinion of the investigator. 
None 
Grade 2 
Requires therapy or 
infusion interruption 
but responds promptly 
to symptomatic 
treatment (e.g., 
antihistamines, 
NSAIDs, narcotics, IV 
fluids); prophylactic 
medications indicated 
for ≤24 hrs 
Stop Infusion. 
Additional appropriate medical therapy may 
include but is not limited to: 
IV fluids 
Antihistamines 
NSAIDs 
Acetaminophen 
Narcotics 
Increase monitoring of vital signs as medically 
indicated until the subject is deemed medically 
stable in the opinion of the investigator. 
If symptoms resolve within 1 hour of stopping 
drug infusion, the infusion may be restarted at 
50% of the original infusion rate (e.g. from 100 
mL/hr to 50 mL/hr).  Otherwise dosing will be 
held until symptoms resolve and the subject 
should be premedicated for the next scheduled 
dose. 
Subjects who develop Grade 2 toxicity despite 
adequate premedication should be 
permanently discontinued from further study 
drug treatment 
Subject may be premedicated 
1.5h (± 30 minutes) prior to 
infusion of pembrolizumab 
with: 
Diphenhydramine 50 mg po 
(or equivalent dose of 
antihistamine). 
Acetaminophen 500-1000 mg 
po (or equivalent dose of 
analgesic). 
Grades 3 or 4 
Grade 3: 
Prolonged (i.e., not 
rapidly responsive to 
symptomatic 
medication and/or brief 
interruption of 
infusion); recurrence of 
symptoms following 
initial improvement; 
hospitalization 
indicated for other 
clinical sequelae (e.g., 
renal impairment, 
pulmonary infiltrates) 
Grade 4: 
Life-threatening; 
pressor or ventilatory 
support indicated 
Stop Infusion. 
Additional appropriate medical therapy may 
include but is not limited to: 
Epinephrine** 
IV fluids 
Antihistamines 
NSAIDs 
Acetaminophen 
Narcotics 
Oxygen 
Pressors 
Corticosteroids 
Increase monitoring of vital signs as medically 
indicated until the subject is deemed medically 
stable in the opinion of the investigator. 
Hospitalization may be indicated. 
**In cases of anaphylaxis, epinephrine should be 
used immediately. 
Subject is permanently discontinued from 
further study drug treatment. 
No subsequent dosing 
Appropriate resuscitation equipment should be available at the bedside and a physician readily available during the period 
of drug administration. 
For further information, please refer to the Common Terminology Criteria for Adverse Events v4.0 (CTCAE) at 
http://ctep.cancer.gov 
 

 
60 
 
Dosing delays of up to 7 days are permitted at physician discretion for medical / surgical events 
or logistical reasons. Dosing interruptions (missing a dose) are permitted in the case of medical 
/ surgical events or logistical reasons not related to study therapy (e.g., elective surgery, 
unrelated medical events, subject vacation, and/or holidays), not to exceed two consecutive 
doses or a maximum of 9 weeks. The reason for interruption will be documented in the 
subject’s study record. 
 
There is limited data regarding optimal therapy for refractory and/or persistent side effects 
from pembrolizumab (after discontinuation of pembrolizumab and initiation of steroids). 
These subjects will be managed as per treating physician’s discretion in consultation with the 
pembrolizumab clinical team at Merck & Co. This may include but not limited to the use of 
drugs such as infliximab (5 mg/kg). If symptoms persist after the first infliximab dose, a second 
dose of infliximab (5 mg/kg) may be repeated two weeks after the initial dose. 
 
7.13 Dose Modifications for Ferumoxytol and Temozolomide 
Ferumoxytol 
There will be no dose limitations or modifications to ferumoxytol. If subject experiences a 
grade 2 or greater allergic or anaphylactic reaction (CTCAE v 4.0) that is directly attributable 
to the ferumoxytol, the subject will be removed from study. 
Temozolomide (arm 2 only)  
Temozolomide will be administered as described in section 7.6 with standard dose 
modifications per the product prescribing information (Section 14.4. Subject may remain on 
study and continue on pembrolizumab if temozolomide is stopped. 
 
In the concomitant setting (daily during radiation) the dose of temozolomide will be 75mg/m2 
per day. Dose will be held for ANC less than 1000/µL or platelet count less than 100,000/µL 
and the dose will be held until ANC is over 1000/µL or platelet count over 100,000/µL .In the 
adjuvant setting (monthly after completing radiation), dosage of temozolomide must be 
adjusted according to nadir neutrophil and platelet counts in the previous cycle and neutrophil 
and platelet counts at the time of initiating the next cycle. The initial dose is 150 mg/m2 orally 
once daily for 5 consecutive days per 28-day treatment cycle. Temozolomide dose may be 
increased to 200 mg/m2 /day for 5 consecutive days per 28-day treatment cycle. The general 
algorithm for dose adjustment is as follows:  
 

 
61 
 
 
 
Additionally, for subjects in arm 2 who will receive temozolomide and pembrolizumab, 
although there is no concern for overlapping toxicities, in cases where attribution to one drug 
of the other is unclear, the dose of pembrolizumab will be modified or discontinued based on 
the guildelines in table 6. If the toxicity resolves appropriately, pembrolizumab will be 
restarted. Temozolomide will be modified or discontinued at the discretion of the treating 
physician  
 
Radiation   
Radiation will be administered as described in section 7.4. Subject may remain on study and 
continue on pembrolizumab and/or temozolomide if radiation is stopped for toxicities 
attributed to radiation. 
 
7.14 Trial Blinding/Masking 
This is an open-label pilot trial; therefore, the Sponsor, investigator and subject will know the 
treatment administered. 
 
7.15 Randomization or Treatment Allocation 
N/A 
 
7.16 Stratification 
N/A 
 
7.17 Concomitant Medications/Vaccinations (allowed & prohibited) 
Medications or vaccinations specifically prohibited in the exclusion criteria are not allowed 
during the ongoing trial.  If there is a clinical indication for one of these or other medications 
or vaccinations specifically prohibited during the trial, discontinuation from trial therapy or 
vaccination may be required.  The investigator should discuss any questions regarding this 
with the Merck Clinical team.  The final decision on any supportive therapy or vaccination 
rests with the investigator and/or the subject's primary physician. 
 
7.17.1 Acceptable Concomitant Medications 
All treatments that the investigator considers necessary for a subject’s welfare may be 
administered at the discretion of the investigator in keeping with the community standards of 

 
62 
 
medical care.  All concomitant medication will be recorded in Epic including all prescription, 
over-the-counter (OTC), herbal supplements, and IV medications and fluids.   
 
All concomitant medications received within 28 days before the first dose of trial treatment 
and 30 days after the last dose of trial treatment should be recorded.  Concomitant medications 
administered after 30 days after the last dose of trial treatment should be recorded for SAEs 
and ECIs. 
 
7.17.2 Prohibited Concomitant Medications and Therapies 
Subjects are prohibited from receiving the following therapies during the Screening and 
Treatment Phase (including retreatment for post-complete response relapse) of this trial: 
• Antineoplastic systemic chemotherapy or biological therapy not specified in this 
protocol 
• Immunotherapy not specified in this protocol 
• Chemotherapy not specified in this protocol 
• Live vaccines within 30 days prior to the first dose of trial treatment and while 
participating in the trial.  Examples of live vaccines include, but are not limited to, the 
following: measles, mumps, rubella, varicella/zoster, yellow fever, rabies, BCG, and 
typhoid vaccine. 
• All herbal and natural supplements that are being used will be recorded at all clinic 
visits. Natural therapies and herbal supplements may stimulate or suppress subject’s 
immune system. Immune suppressants may reduce the efficacy of pembrolizumab and 
their concomitant use may potentially increase the risk of infections. Concomitant use 
of immune stimulants may potentially increase the risk of adverse auto-immune 
responses. Concomitant use of the natural therapies and herbal supplements in Table 8 
below are prohibited 
• Emerging data suggests that marijuana can affect response rates. The use of marijuana 
and marijuana derived produces are allowed in this study. Subjects will be made aware 
(in the consent form) of the potential risks of using marijuana while on the study. 
 
Table 8 Prohibited Concomitant Natural Therapies and Herbal Supplements 
Name  of herbal supplement 
Immune stimulating agents 
1. Coriolus MushroomDHEA 
2. 7-keto-DHEA 
3. Echinacea* 
4. European mandrake 
5. European mistletoe 
6. Fo-Ti Root 
7. Ginseng, panax and siberian 
8. Glossy Privet (ligustrum) 
9. Greater Celandine 
10. Jiaogulan 
11. Larch Arabinogalactan 
12. Lycium 
13. Melatonin 
14. MGN-3 
15. Podophyllum 
16. Pokeweed 
17. Pycnogenol 
18. Coriolus Mushroom 
19. DHEA 
20. 7-keto-DHEA 
21. European mandrake 
22. Quillaia 
23. Reishi Mushroom (gandoderma) 
24. Shitake Mushroom 
25. Sweet Annie 
26. Terminalia chebula 
27. Thunder god vine 
28. Wild indigo 
29. Zinc 
Note:*Can be immune suppressing also 

 
63 
 
Immune suppressing agents 
1. Bitter Melon 
2. Caramel Color 
3. Carrageenan(intravenous only) 
4. Echinacea** 
5. Indole-3-carbinol 
6. Ipriflavone 
7. Hydrazine 
 
8. Fish Oils 
9. Licorice 
10. Periwinkle(vinca) 
11. Poria Mushroom 
Note : ** Can be immune stimulating also 
 
 
Subjects who, in the assessment by the investigator, require the use of any of the 
aforementioned treatments for clinical management should be removed from the trial.  Subjects 
may receive other medications that the investigator deems to be medically necessary. 
 
The Exclusion Criteria describes other medications which are prohibited in this trial. 
There are no prohibited therapies during the Post-Treatment Follow-up Phase. 
 
7.18 Pharmacokinetic/Pharmacodynamic Evaluations 
NA 
 
7.19 Blood Collection for Anti-Pembrolizumab Antibodies 
NA 
 
7.20 Blinding/Unblinding 
N/A 
 
7.21 Diet/Activity/Other Considerations 
Subjects should maintain a normal diet unless modifications are required to manage an AE 
such as diarrhea, nausea or vomiting. 
 
7.22 Contraception 
Both pembrolizumab and ferumoxytol may have adverse effects on a fetus in utero.  
Furthermore, it is not known if pembrolizumab has transient adverse effects on the composition 
of sperm.  Non-pregnant, non-breast-feeding women may be enrolled if they are willing to use 
2 methods of birth control or are considered highly unlikely to conceive.  Highly unlikely to 
conceive is defined as 1) surgically sterilized, or 2) postmenopausal (a woman who is ≥45 
years of age and has not had menses for greater than 1 year without alternate medical causes 
will be considered postmenopausal), or 3) not heterosexually active for the duration of the 
study. In women ≤ 45 years of age a high follicular stimulating hormone (FSH) level in the 
post-menopausal range may be used to confirm post menopausal state in women not using 
hormonal contraception or hormonal replacement therapy. The two birth control methods can 
be either two barrier methods or a barrier method plus a hormonal method to prevent 
pregnancy. Subjects should start using birth control from study Visit 1 throughout the study 
period up to 120 days after the last dose of study therapy.  Male subjects should agree to use 
an adequate method of contraception, including but not limited to, abstinence from 
heterosexual activity, starting with the first dose of study therapy through 120 days after the 
last dose of study therapy. 
 

 
64 
 
The following are considered adequate barrier methods of contraception: diaphragm, condom 
(by the partner), copper intrauterine device, sponge, or spermicide.  Appropriate hormonal 
contraceptives will include any registered and marketed contraceptive agent that contains an 
estrogen and/or a progestational agent (including oral, subcutaneous, intrauterine, or 
intramuscular agents). 
 
Subjects should be informed that taking the study medication may involve unknown risks to 
the fetus (unborn baby) if pregnancy were to occur during the study.  In order to participate in 
the study they must adhere to the contraception requirement (described above) from study Visit 
1 throughout the study period up to 120 days after the last dose of study therapy. If there is any 
question that a subject will not reliably comply with the requirements for contraception, that 
subject should not be entered into the study. 
 
7.23 Use in Pregnancy 
If a subject inadvertently becomes pregnant while on treatment with pembrolizumab or 
ferumoxytol, the subject will immediately be removed from the study.  The site will contact 
the subject at least monthly and document the subject’s status until the pregnancy has been 
completed or terminated.  The outcome of the pregnancy will be reported to the Sponsor and 
to Merck without delay and within 24 hours to the Sponsor and within 2 working days to Merck 
if the outcome is a serious adverse experience (e.g., death, abortion, congenital anomaly, or 
other disabling or life-threatening complication to the mother or newborn). 
 
The study investigator will make every effort to obtain permission to follow the outcome of 
the pregnancy and report the condition of the fetus or newborn to the Sponsor.   If a male 
subject impregnates his female partner, the study personnel at the site must be informed 
immediately and the pregnancy reported to the Sponsor and to Merck. 
 
7.24 Use in Nursing Women 
It is unknown whether pembrolizumab or ferumoxytol is excreted in human milk.  Since many 
drugs are excreted in human milk, and because of the potential for serious adverse reactions in 
the nursing infant, subjects who are breast-feeding are not eligible for enrollment. 
 
8.0 RESPONSE 
ASSESSMENT, 
IMAGE 
PROCESSING 
AND 
BIOMARKERS 
 
8.1 
Definitions for Response assessment: 
The study will use the following criteria for the assessment of brain lesions. 
 
Complete response (CR): Complete disappearance of all enhancing abnormalities on clinical 
enhanced MRI scan (in the absence of gadolinium, ferumoxytol enhancement will be used).  
Some subjects will have a small but persistent enhancing abnormality on MRI related to biopsy 
or focal hemorrhage.  It is often difficult to ascertain whether this represents a residual nidus 
of tumor or scar tissue.  Adjunctive radiologic studies such as SPECT or PET as clinically 
indicated may be helpful, but often the nature of these abnormalities may only be determined 
by following the subject with serial scans.  If this type of abnormality does not change or slowly 
involutes over time off therapy and corticosteroids, it is reasonable to categorize it as a CR. 

 
65 
 
 
Partial Response (PR): At least 50% decrease in the contrast enhancing lesion seen on MRI 
as compared to baseline imaging.  In the event of multiple lesions, the determination of partial 
response will be based on the sum of the bi-dimensional measurements (greatest diameter x 
greatest perpendicular) across lesions AND no new sites of disease 
 
Stable disease (SD): less than a PR but is not progressive disease. 
 
Progressive disease (PD): 
• Suspected Radiographic Progression: progression will be defined by a 20% increase 
in volume of enhancement compared to the best response on clinical standard of care 
MRI. At any time point if progression is suspected on the clinical scan, additional 
steady state ferumoxytol MRI will be performed within 7 days of the clinical scan. 
Progression will then be confirmed with a follow up scan in 4 weeks +/-5 days with a 
clinical standard of care MRI scan and additional ferumoxytol scan. 
 
• Persistent Radiographic Progression: sustained and evident progression greater than  
increase in volume of enhancement compared to best response on a follow up scan at 
least 4 weeks after the scan where progression was suspected as per RANO BM form 
arm 1 or RANO criteria for subjects in arm 2. In cases with persistent radiographic 
progression the date of initial scan when progression was suspected will be considered 
to be the date of progression. 
 
• Appearance of any new lesion or site of disease in the brain during or at the end of 
therapy. 
 
• Confirmation of true progression: For the purpose of this study, Histopathologic 
evidence of viable tumor cells in patients with persistent radiographic progression will 
be define to have confirmed true progression. True progression is confirmed by 
histopathology, Pembrolizumab will be stopped and patient swill be taken off-study.. 
Patients who refuse biopsy or biopsy is not deemed clinically necessary will be taken 
off study at persistent radiographic progression. However, they will be continued to be 
monitored with clinical MRI scan and until death. 
 
• Pseudoprogression (PsP): for the purpose of this pilot study, PsP may be confirmed 
by imaging or by pathology. 
o PsP Imaging: stable or decrease in volume of enhancement at 4 weeks (+5 days) 
after suspected radiographic progression. 
o PsP pathology: No viable tumor tissue is seen by histopathology evaluation on 
tissue obtained after confirmed radiographic progression by imaging. 
 
• Clinical progression: Subjects may be removed from study if they experience 
symptomatic deterioration without radiographic evidence of disease progression. 
 
Not evaluable (NE): Only relevant if any of the target lesions had additional interventions for 
clinical managements, patient is unable to get follow up scans or images are of poor quality. 

 
66 
 
 
Duration of Best Response: The duration of best response is measured from the time 
measurement criteria are met for SD, CR or PR (whichever is first recorded) until the first date 
that recurrent or PD is objectively documented (taking as reference for PD the smallest 
measurements recorded since the treatment started). 
 
Progression free survival and overall survival will be calculated from the date of diagnosis to 
the date of confirmed progression or death, respectively. The date of diagnosis was used 
because the time between the date of diagnosis and the start of treatment or date of enrollment 
may vary due to subject variables or logistical issues based on radiation planning.  
 
Systemic Lesions (only for Arm 1): 
Measurements based on RECIST version 1.1 will be used to make a diagnosis of suspected 
systemic progression; it will be confirmed using irRC at follow-up. 
 
8.2 
Image processing 
Image processing will be done at OHSU. 
 
8.2.1 For CNS lesions: 
SS-CBV maps will be created using the high resolution T2*w scans before and after contrast 
agent and ΔR2* maps will be created using the formula ΔR2*=ln(SIpre/SIpost)/TE, in which 
SIpre and SIpost indicate the signal intensities pre- and post ferumoxytol, and TE is the echo 
time. DSC-CBV maps from gadoteridol DSC will be created using a mathematical leakage 
correction method in NordicICE (Nordic Neurolab, Bergen, Norway) an FDA approved 
perfusion MRI software (if gadoteridol could not be given per institutional protocol (see 
protocol below) ferumoxytol enhancement will be used). The coregistration and overlay of 
CBV maps on T1-w MPRAGE will be done using NordicICE as well [27, 33]. The clinical 
MR sequences, such as T1 weighted scans with and without gadoteridol, and T2 weighted pre 
contrast scans will also be read. Images will be read by 2 radiologists. The radiologists will be 
blinded to the type of CBV maps (SS and DSC) and subject information. 
 
8.2.2 Oregon Health & Science University policy on assessment of lab results prior to 
gadolinium based contrast media 
For patients with the following risk factors, a serum creatinine level will be obtained with 
calculation of eGFR according to the following guidelines:   
  
1) Creatinine/eGFR NOT required:  
• Dialysis patients – No eGFR required 
• Dialysis patients are excluded from the requirements in numbers 2 and 3 below.  
  
2) Creatinine/eGFR required within 24 hours of MRI scan: 
• All inpatients (includes Daypatients and ER patients) 
• Outpatients whose most recent eGFR<60    
  
3) Creatinine/eGFR required within 30 days of MRI scan:   

 
6 7  
 
•  Patie nts > 6 0 years of a ge  
•  O ut patie nts wit h a hist or y of h y perte nsi o n re q uiri n g me dicati o n  
•  O ut patie nts wit h dia betes mellit us  
•  O ut patie nts wit h ki d ne y disease: ki d ne y tra ns pl a nt, si n gle ki d ne y, ki d ne y 
ca ncer, ki d ne y s ur g er y   
•  O ut patie nt c hil dre n < 1 y ear of a ge  
 
T he tec h n ol o gist or R N will n otif y t he ra di ol o gist f or t he f oll o wi n g:  
 
1) Patie nt has a hist or y of N S F ( Ne p hr o ge ni c S yste mic Fi br osis  
2) Patie nt is o n dial ysis  
3) Patie nts wit h e G F R < 3 0 m L/ mi n/ 1. 7 3 m 2  
4) Patie nt recei ve d ga d oli ni u m base d c o ntrast me dia wit hi n t he past 2 4 h o urs  
5) F or q uesti o ns relate d t o ki d ne y f u ncti o n or pati e nt hist or y  
  
I nf or me d C o nse nt: T he ra di ol o gist will o btai n i nf or me d c o nse nt a n d d oc u me nt ris k/ be nefit of 
pr oce d ure i n t he patie nt’s me dical rec or d f or a n y of t he f oll o wi n g patie nts w h o will be 
recei vi n g I V ga d oli ni u m-base d c o ntr ast:  
  
1)  Patie nts wit h e G F R < 3 0  
2)  ) Patie nts o n dial ysis 
 
8. 2. 3  F or s yste mic lesi o ns ( o nl y Ar m 1).  
Wit h i m m u n ot hera p y treat me nt, a n i ncrease i n t otal t u m or b ur de n of pre vi o usl y sta ble 
s yste mic lesi o ns (t u m or flare reacti o n) has bee n d escri be d [9 2 ]. B ase d o n t h e l ocati o n of t he 
s yste mic lesi o ns, a n d t he feasi bilit y of M R i ma gi n g, s u bjects i n Gr o u p 1 ( m ela n o ma) will be 
offere d o pti o nal M R i ma gi n g of s yste mic lesi o ns, t o e val uate res p o nse as p art of t he 
e x pl orat or y e n d p oi nts. O nl y s u bjects wit h meas ure a ble, b ut sta ble, s yste mi c i n v ol ve me nt at 
t he ti me of e nr oll me nt, will be c o nsi dere d f or t his i ma gi n g. S u bjects m ust pr o vi de a d diti o nal 
c o nse nt f or t his o pti o nal p orti o n of t he st u d y.  
 
Fracti o nal Bl o o d V ol u me (f B V), V essel Size I n d e x ( V SI), a n d Vessel De nsit y I n d e x ( V DI)  v al ues 
will be o btai ne d b y defi ni n g a re gi o n of i nterest o ver t he e ntire t u m or area.  T his pr ocess will be 
re peat e d f or 3 ce ntral slices of t he t u m or f or e v er y lesi o n, a n d t he m ea n v al ue wit hi n t he re gi o n of 
i nterest ( R OI) will be calc ulate d. T 2 a n d T 2 * val ues will be o btai ne d, usi n g G R E a n d S E data 
res pecti vel y, b y pl otti n g mea n R OI val ue at eac h ec h o, a n d calc ulati n g t h e best-fit e x p o ne ntial 
deca y f u ncti o n. R 2 a n d R 2 * will be defi ne d as t he i n verse of T 2 or T 2 * val u es; 
, 
 will be 
calc ulate d as t he rati o of val ues bef ore a n d after ir o n c o ntrast i njecti o n.  
Fracti o nal Bl o o d V ol u me of t he t u m or was deri ve d fr o m t he relati o ns hi p of 
, fracti o nal bl o o d 
v ol u me (f B V) a n d ma g n etic fiel d c o nsta nts (
,
) t o c ha n ges i n ma g netic s us ce pti bilit y, 
. 
 
 
D R 2
D R 2
*
D R 2
*
g B 0
D c
D c =
3
4 p
D R 2, m uscle
*
f B Vm uscle g B 0
=
3
4 p
D R 2, t u m or
*
f B Vt u m org B 0

 
6 8  
 
 
 
w here f B V m uscle  is ass u me d t o be a c o nsta nt of 3 %. 
Vessel Size I n d e x will be c o m p ute d usi n g t he f oll o wi n g e q uati o n: 
 
F or n or malize d val ue calc ulati o ns, t he first t w o t er ms will be c o nsi dere d t o be c o nst a nt f or all 
i ma ges a n d will be t heref ore disre gar de d. 
Vessel De nsit y I n de x was c o m p ute d as f oll o ws:  
 
As f or t he V SI calc ulati o ns, t he first ter m i n t he V DI e q uati o n will be disre gar de d d uri n g 
calc ulati o n of n or m alize d val ues.  
 
Para ma g netic m a ps will als o ge nerate d b y calc ul ati n g V SI, V DI a n d f B V val ues o n a v o xel -b y -
v o xel basis. Hist o gra ms will be o btai ne d b y pl otti n g vessel i n dices wit hi n a t u m or re gi o n -of -
i nterest a gai nst t he fre q u e nc y of occ urre nce. 
 
Data will be re p orte d as f B V, V SI a n d V DI +/ - sta n dar d err or of t he m ea n. 
 
8. 3  
T u m or Tiss ue C ollecti o n a n d C orrel ati ve Bl o o d Bi o m ar ker St u dies  
8. 3. 1  Bl o o d Bi o m ar kers  - O pti o n al  
•  C orrelate cli nic al a n d ra di ol o gical res p o nse wit h s yste mic i m m u ne res p o nses usi n g 
m ultic ol or fl o w c yt o metr y, meas uri n g t otal T -cells ( C D 3 +) wit h C D 4/ C D 8 rati o,  
•  T -Re g ( C D 4 +/ C D 1 2 7 -/ bri g ht 
C D 2 5 +), 
D N T ( C D 3 +/ C D 4-/ C D 8-), 
Naï ve 
T 
( C D 3 +/ C D 4 5 R A +), me m or y T ( C D 3 +/ C D 4 5 R O +), T-cell acti vati o n ( C D 3 +/ varia ble 
C D 6 9 +/ varia ble 
C D 2 5 +/ varia ble 
H L A -D R),  
N K a n d 
N K -acti vati o n ( C D 3 -
/ C D 5 6 +/ vari ble C D 1 6 +), t otal B-cells ( C D 1 9 +), n aï ve B -cells ( C D 1 9 +/I g D +/ C D 2 7 -), 
me m or y B -cells ( C D 1 9 +/I g D -/ C D 2 7 +). 
•  Bl o o d will be c ollecte d  + 1 5  da ys of eac h fer u m o x yt ol M RI s ca n. T hese ti me p oi nts are:  
at baseli ne, at 4  wee ks after t h e last da y of ra diati o n, at s us pici o n of ra di o gra p hic 
pr o gressi o n, a n d 4  wee ks after s us pecte d ra di o gr a p hic pr o gressi o n.  A ll ti me p oi nts + 1 5 
da ys . 
•  Bl o o d sa m ples will be c ollecte d at O H S U a n d pr ocesse d at t he O H S U researc h 
la b orat or y. 
 
8. 3. 2  Tiss ue Bi o m ar kers  
P D -L 1 testi n g will be perf or me d b y t he C R O Q ual Te k M olec ular L a b orat ories.  A n y arc hi ve d 
tiss ue sa m ples or tiss ue o btai ne d fr o m brai n bi o ps y pri or t o e nr oll me nt (arc hi val tiss ue) a n d 
t h ose o btai ne d at s us pecte d ra di o gra p hic pr o gressi o n will be se nt t o t he C R O f or P D -L 1 
e x pressi o n assa y.  We will c orrelate o utc o m es a n d i ma gi n g fi n di n gs wit h P D -L 1 e x pressi o n i n 
arc hi val s yste mic t u m or tiss ue, brai n bi o ps y pri or t o e nr oll me nt, a n d tiss ue o btai ne d at 
3
4 p
D R 2, m uscle
*
f B Vm uscle g B 0
=
3
4 p
D R 2, t u m or
*
f B Vt u m org B 0
f B Vt u m or = f B Vm uscle
D R 2, t u m or
*
D R 2, m uscle
*
V SI = 0. 4 2 4( A D C
gD c B 0
)1/ 2 D R 2
*
D R 2
V DI = 3 2 9 D R 2
D R 2
*

 
69 
 
persistent radiographic progression. Frozen tissue and fixed tissue blocks from initial lung 
biopsies will be used. In a subset frozen sections and fixed tissue blocks from subjects who 
undergo resection of brain metastases for clinical indications will also be utilized. 
 
9.0 ADVERSE EVENTS 
9.1 
Adverse Event (AE) Monitoring 
The investigator or qualified designee will assess each subject to evaluate for potential new or 
worsening AEs as specified in the Schedule of Events and more frequently if clinically 
indicated.  All adverse events will be monitored continuously by the PI in order to stop 
treatment as soon as a subject experiences grade 3 or greater AE attributed to pembrolizumab, 
ferumoxytol, or both. Adverse experiences will be graded and recorded throughout the study 
and during the follow-up period according to NCI CTCAE Version 4.0.  Toxicities will be 
attributed and graded, and action taken with regard to trial treatment will be recorded. 
 
AEs will be attributed as unrelated, related or possibly related to: 
1) pembrolizumab 
2) ferumoxytol 
3) standard of care therapies:  
Arm 1: stereotactic radiosurgery 
Arm 2: radiation and temozolomide 
 
For subjects receiving treatment with pembrolizumab, all AEs of unknown etiology associated 
with Pembrolizumab exposure should be evaluated to determine if it is possibly an event of 
clinical interest (ECI) of a potentially immunologic etiology (termed immune-related adverse 
events, or irAEs). 
 
9.2 
Sponsor Responsibility for Reporting Adverse Events 
All Adverse Events will be reported to regulatory authorities, IRB/IECs and investigators in 
accordance with all applicable global laws and regulations. 
 
9.3 
OHSU IRB Reporting of Reportable New Information and Adverse Events (only if 
applicable) 
Reportable New Information (RNI) and Adverse Events (AE) will be reported to IRB 
according to the policies, procedures and guidelines posted on the OHSU IRB web site: 
• Fatal and life-threatening RNI will be reported to OHSU IRB within 5 days of 
notification of the event. All other reports will also be submitted to OHSU IRB no later 
than 5 days of occurrence or notification of the event. Copies of the report documents 
will be kept in the study regulatory binder. 
• Reportable New Information is submitted through OHSU eIRB and will be reviewed 
by OHSU Knight Cancer Institute and IRB. 
 
9.4 
Assessing and Recording Adverse Events 
An adverse event is defined as any untoward medical occurrence in a patient or clinical 
investigation subject administered a pharmaceutical product and which does not necessarily 
have to have a causal relationship with this treatment. An adverse event can therefore be any 

 
70 
 
unfavorable and unintended sign (including an abnormal laboratory finding, for example), 
symptom, or disease temporally associated with the use of a medicinal product or protocol-
specified procedure, whether or not considered related to the medicinal product or protocol-
specified procedure.  Any worsening (i.e., any clinically significant adverse change in 
frequency and/or intensity) of a preexisting condition that is temporally associated with the use 
of the Merck’s product, is also an adverse event. 
 
Changes resulting from normal growth and development that do not vary significantly in 
frequency or severity from expected levels are not to be considered adverse events.  Examples 
of this may include, but are not limited to, teething, typical crying in infants and children and 
onset of menses or menopause occurring at a physiologically appropriate time. Merck product 
includes any pharmaceutical product, biological product, device, diagnostic agent or protocol-
specified procedure, whether investigational (including placebo or active comparator 
medication) or marketed, manufactured by, licensed by, provided by or distributed by Merck 
for human use. 
 
Adverse events may occur during the course of the use of Merck product in clinical trials or 
within the follow-up period specified by the protocol, or prescribed in clinical practice, from 
overdose (whether accidental or intentional), from abuse and from withdrawal. Adverse events 
may also occur in screened subjects during any pre-allocation baseline period as a result of a 
protocol-specified intervention, including washout or discontinuation of usual therapy, diet, 
placebo treatment or a procedure. 
 
Progression of the cancer under study is not considered an adverse event unless it is considered 
to be drug related by the investigator. 
 
All adverse events will be recorded from the time the consent form is signed through 30 days 
following cessation of treatment and at each examination on the Adverse Event case report 
forms/worksheets. 
 
9.5 
Rescue Medications & Supportive Care 
9.5.1 Supportive Care Guidelines 
Subjects should receive appropriate supportive care measures as deemed necessary by the 
treating investigator.  Suggested supportive care measures for the management of adverse 
events with potential immunologic etiology are outlined below and in greater detail in the ECI 
guidance document. Where appropriate, these guidelines include the use of oral or intravenous 
treatment with corticosteroids as well as additional anti-inflammatory agents if symptoms do 
not improve with administration of corticosteroids.   Note that several courses of steroid 
tapering may be necessary as symptoms may worsen when the steroid dose is decreased. For 
each disorder, attempts should be made to rule out other causes such as metastatic disease or 
bacterial or viral infection, which might require additional supportive care. The treatment 
guidelines are intended to be applied when the investigator determines the events to be related 
to pembrolizumab. 
 
Note: if after the evaluation the event is determined not to be related, the investigator is 
instructed to follow the ECI reporting guidance but does not need to follow the treatment 

 
71 
 
guidance (as outlined in the ECI guidance document). Refer to Section 7.12 for dose 
modification. 
 
It may be necessary to perform conditional procedures such as bronchoscopy, endoscopy, or 
skin photography as part of evaluation of the event. Suggested conditional procedures, as 
appropriate, can be found in the ECI guidance document. 
 
9.5.2 Expected AEs due to Pembrolizumab and Guidelines for Management 
• Pneumonitis:  
o For Grade 2 events, treat with systemic corticosteroids. When symptoms 
improve to Grade 1 or less, steroid taper should be started and continued over 
no less than 4 weeks. 
o For Grade 3-4 events, immediately treat with intravenous steroids.  Administer 
additional anti-inflammatory measures, as needed. 
o Add prophylactic antibiotics for opportunistic infections in the case of 
prolonged steroid administration. 
 
• Diarrhea/Colitis:  
Subjects should be carefully monitored for signs and symptoms of enterocolitis (such 
as diarrhea, abdominal pain, blood or mucus in stool, with or without fever) and of 
bowel perforation (such as peritoneal signs and ileus).   
o All subjects who experience diarrhea/colitis should be advised to drink liberal 
quantities of clear fluids.  If sufficient oral fluid intake is not feasible, fluid and 
electrolytes should be substituted via IV infusion.  For Grade 2 or higher 
diarrhea, consider GI consultation and endoscopy to confirm or rule out colitis. 
o For Grade 2 diarrhea/colitis that persists greater than 3 days, administer oral 
corticosteroids.  
o For Grade 3 or 4 diarrhea/colitis that persists > 1 week, treat with intravenous 
steroids followed by high dose oral steroids.   
o When symptoms improve to Grade 1 or less, steroid taper should be started and 
continued over no less than 4 weeks. 
 
• Type 1 diabetes mellitus (if new onset, including diabetic ketoacidosis [DKA]) or 
≥ Grade 3 Hyperglycemia, if associated with ketosis (ketonuria) or metabolic 
acidosis (DKA) 
 
o For T1DM or Grade 3-4 Hyperglycemia 
▪ Insulin replacement therapy is recommended for Type I diabetes 
mellitus and for Grade 3-4 hyperglycemia associated with metabolic 
acidosis or ketonuria.  
▪ Evaluate subjects with serum glucose and a metabolic panel, urine 
ketones, glycosylated hemoglobin, and C-peptide.  
 
• Hypophysitis: 
o For Grade 2 events, treat with corticosteroids. When symptoms improve to 
Grade 1 or less, steroid taper should be started and continued over no less than 

 
72 
 
4 weeks. Replacement of appropriate hormones may be required as the steroid 
dose is tapered. 
o For Grade 3-4 events, treat with an initial dose of IV corticosteroids followed 
by oral corticosteroids. When symptoms improve to Grade 1 or less, steroid 
taper should be started and continued over no less than 4 weeks. Replacement 
of appropriate hormones may be required as the steroid dose is tapered. 
 
• Hyperthyroidism or Hypothyroidism:  
Thyroid disorders can occur at any time during treatment. Monitor subjects for changes 
in thyroid function (labs every 3 months) and for clinical signs and symptoms of thyroid 
disorders. 
o Grade 2 hyperthyroidism events (and Grade 2-4 hypothyroidism): 
▪ In hyperthyroidism, non-selective beta-blockers (e.g. propranolol) are 
suggested as initial therapy. 
▪ In hypothyroidism, thyroid hormone replacement therapy, with 
levothyroxine or liothyroinine, is indicated per standard of care. 
o Grade 3-4 hyperthyroidism  
▪ Treat with an initial dose of IV corticosteroid followed by oral 
corticosteroids. When symptoms improve to Grade 1 or less, steroid 
taper should be started and continued over no less than 4 weeks. 
Replacement of appropriate hormones may be required as the steroid 
dose is tapered. 
 
• Hepatic: 
o For Grade 2 events, monitor liver function tests more frequently until returned 
to baseline values (consider weekly). 
▪ Treat with IV or oral corticosteroids 
o For Grade 3-4 events, treat with intravenous corticosteroids for 24 to 48 hours.  
o When symptoms improve to Grade 1 or less, a steroid taper should be started 
and continued over no less than 4 weeks. 
 
• Renal Failure or Nephritis: 
o For Grade 2 events, treat with corticosteroids. 
o For Grade 3-4 events, treat with systemic corticosteroids. 
o When symptoms improve to Grade 1 or less, steroid taper should be started and 
continued over no less than 4 weeks.  
 
• Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN):  
o One fatal case of SJS in a clinical trial and one fatal case of TEN in the post-
marketing setting have been reported in patients treated with pembrolizumab. 
Including these cases, there have been 8 cases of SJS (6 in clinical trials, and 2 
post-marketing) and 2 cases of TEN (both post-marketing) all of which were 
serious. 
o The risk of SJS and TEN is reported at approximately 0.4 - 7 cases per million 
patient years in the general adult population. 

 
73 
 
o Independent risk factors include certain medications such as anticonvulsants, 
sulfonamides, aminopenicillins, allopurinol, and NSAIDs. Non-medication 
triggers include infection, contrast media, and vaccinations. 
o Malignancy is associated with an increased mortality rate in patients with SJS 
and TEN. 
 
For signs or symptoms of SJS or TEN, withhold Pembrolizumab and refer the 
patient for specialized care for assessment and treatment. If SJS or TEN is 
confirmed, permanently discontinue Pembrolizumab.  
 
• Immune-mediated myocarditis  
A total of 6 cases of myocarditis have been reported in patients treated with 
pembrolizumab in clinical trials or in an expanded access program. There were was 1 
fatal case reported in a clinical trial. 
 
A search of the literature identified neither background incidence rates nor prevalence 
of myocarditis specifically among cancer patients. Immune-mediated myocarditis 
should be suspected if other causes of myocarditis, such as infection or prior radiation 
therapy, have been excluded. Risk factors include certain medications and treatment 
modalities such as radiation, anthracycline, alkylating agents and most recently 
checkpoint inhibitors. For suspected immune-mediated myocarditis, ensure adequate 
evaluation to exclude other etiologies, and administer corticosteroids.  
 
• Management of Infusion Reactions: Signs and symptoms usually develop during or 
shortly after drug infusion and generally resolve completely within 24 hours of 
completion of infusion.  
 
9.5.3 Expected AEs from Ferumoxytol and Guidelines for Management 
Possible risks and side effects of the study agent ferumoxytol from the Ferumoxytol 
Investigator’s brochure 2012 are below. There will be no dose limitations or modifications to 
ferumoxytol. If subject experiences a grade 2 or greater allergic or anaphylactic reaction 
(CTCAE v 4.0) that is directly attributable to the ferumoxytol, the subject will be removed 
from study. 
In Phase III clinical studies in subjects with iron deficiency anemia and chronic kidney disease, 
the most commonly reported side effects (≥2% of subjects) following treatment with 
ferumoxytol were diarrhea, nausea, dizziness, hypotension, constipation, and peripheral 
edema. 
 
Pharmacological class effects commonly associated with marketed IV iron products include 
hypotension and hypersensitivity reactions. In clinical studies of ferumoxytol, hypotension was 
reported in 1.9% (33/1726) of subjects. Three of these subjects (0.2%) had related serious 
hypotensive events, one of which was characterized as an anaphylactoid reaction. All of the 
events resolved on the same day of occurrence without sequelae. Serious hypersensitivity 
reactions have been observed in 0.2% (3/1726) of subjects following administration of 

 
74 
 
ferumoxytol. Other adverse reactions potentially associated with hypersensitivity, including 
pruritus, rash, urticaria, or wheezing were reported in 3.7% (63/1726) of subjects; each of these 
reactions occurred in <1% of subjects exposured to ferumoxytol. 
 
The overall incidence of AEs in a post-marketing study irrespective of relationship to study 
medication was lower in subjects administered ferumoxytol (48%) than in those treated with 
iron sucrose (65%). The incidence of SAEs was higher in ferumoxytol-treated subjects than in 
iron sucrose-treated subjects (9% vs 7%). The incidence of related SAEs was similar between 
the two treatment groups (1% in both groups). The most common AEs among ferumoxytol-
treated subjects were nausea (7.5%) and muscle spasms (5.0%). 
 
In the Phase II imaging study where ferumoxytol was used as an imaging agent (doses 1.0, 2.5 
and 4.0 mg/kg) in subjects with peripheral arterial disease (PAD), there was a possible dose 
dependent increase in overall TEAEs reported in this study. Only 3.5% of the subject 
population experienced TEAEs that were related to ferumoxytol. The majority of the 
treatment-related AEs were mild in severity and were resolved. 6.1% of the subject population 
experienced SAEs that were eventually resolved; none were treatment related. There were 3 
AESIs reported in 3 subjects (2.6%); 1 subject in each dose group experienced 1 AESI. In the 
1.0 mg/kg dose group 1 subject experienced acute hypotension. In the 2.5 mg/kg dose group 1 
subject experienced a hypersensitivity reaction of rash, and in the 4.0 mg/kg dose group 1 
subject experienced a drug hypersensitivity reaction (acute hypersensitivity reaction to 
ferumoxytol). 
 
Given the potential for hypersensitivity and other adverse reactions observed with other IV 
anemia therapies, subjects should be monitored for signs and symptoms of hypotension and 
hypersensitivity following administration of ferumoxytol as outlined in study protocols. 
Ferumoxytol should only be administered when personnel and therapies are immediately 
available for the treatment of anaphylaxis and other hypersensitivity reactions. 
 
With certain IV iron preparations, mild to severe low blood phosphorus levels 
(hypophosphatemia) have also frequently been reported following administration, particularly 
in women with heavy AUB. Mild to moderate, asymptomatic reductions in blood phosphorus 
levels have been infrequently observed following ferumoxytol administration. 
 
Elemental iron is essential for normal cell and tissue development, as well as for tumor cell 
growth. There are no clinical data to suggest that therapeutic IV iron supplementation, given 
to correct anemia, stimulates tumor development, despite the theoretical risk. While free iron 
has been implicated in increased oxidative stress, which is potentially associated with cellular 
damage and carcinogenesis, there are no clinical studies to support that transient increases in 
oxidative stress resulting from iron supplementation result in increased tumor growth. 
 
Other potential risks to subjects receiving ferumoxytol include the temporary discomfort at the 
site of injection, as well as the potential for bruising, local infection, and pigmentation 
following IV administration. 
 

 
75 
 
There are no studies of ferumoxytol in pregnant women, and the risk to a pregnant mother and 
unborn baby is unknown. In animal studies, ferumoxytol caused fetal malformations and 
decreased fetal weights at maternally toxic doses of 6 times the human daily dose. Thus 
ferumoxytol should only be used during pregnancy if the potential benefit justifies the potential 
risk to the fetus. 
 
It is also unknown whether ferumoxytol is present in human milk. Animal studies showed that 
when administered daily to pregnant and lactating females, a small amount of ferumoxytol was 
excreted into breast milk. Because many drugs are excreted in human milk and because of the 
potential for adverse reactions in nursing infants, a decision should be made whether to 
discontinue nursing or to avoid ferumoxytol, taking into account the importance of 
ferumoxytol to the mother and the known benefits of nursing. 
 
No data from clinical trials are available regarding overdose of ferumoxytol in humans. During 
the post-marketing phase, several subjects received an overdose of ferumoxytol ranging from 
1 g in 1 day to 2.5 g over 14 days. Only one case of minor rash was observed. 
 
Although this section provides general guidance regarding the risks and side effects associated 
with administration of ferumoxytol, investigators should refer to the protocol for study-specific 
follow-up and the monitoring procedures. 
 
9.6 
Additional IND Reporting Requirements for Ferumoxytol 
Sponsor-investigator of this IND is responsible for compliance with the FDCA (21 U.S.C. §§ 
301 et. seq.) as well as the implementing regulations [Title 21 of the Code of Federal 
Regulations (CFR)]. Responsibilities include: 
• Reporting any unexpected fatal or life-threatening suspected adverse reactions to this 
Division no later than 7 calendar days after initial receipt of the information [21 CFR 
312.32(c)(2)]. If IND is in eCTD format, submit 7-day reports electronically in eCTD 
format. If IND is not in eCTD format, submit 7-day reports by telephone or fax; 
• Reporting any (1) serious, unexpected suspected adverse reactions, (2) findings from 
other clinical, animal, or in-vitro studies that suggest significant human risk, and (3) a 
clinically important increase in the rate of a serious suspected adverse reaction to this 
Division and to all investigators no later than 15 calendar days after determining that 
the information qualifies for reporting [21 CFR 312.32(c)(1)].  If IND is in eCTD 
format, submit 15- day reports to FDA electronically in eCTD format. If IND is not in 
eCTD format, submit 15-day reports in paper format; and 
• Submitting annual progress reports within 60 days of the anniversary of the date that 
the IND went into effect (the date clinical studies were permitted to begin) [21 CFR 
312.33]. 
 
9.6.1 Expected AEs from Temozolomide 
See product insert (section 14.4). Adverse events and toxicities will be managed per 
institutional and accepted standard of care practices.

Product:  MK-3475 
76 
Protocol/Amendment No.:   
 
 
 
 
 
 
Table 9 Evaluating Adverse Events 
An investigator who is a qualified physician, will evaluate all adverse events as to: 
V4.0 
CTCAE 
Grading 
Grade 1 
Mild; asymptomatic or mid symptoms; clinical or diagnostic observations only; intervention not indicated. 
 
Grade 2 
Moderate; minimal, local or noninvasive intervention indicated; limiting age-appropriate instrumental ADL. 
 
Grade 3 
Severe or medically significant but not immediately life-threatening; hospitalization or prolongation or hospitalization indicated; 
disabling; limiting self-care ADL. 
 
Grade 4 
Life threatening consequences; urgent intervention indicated. 
 
Grade 5 
Death related to AE 
Seriousness 
A serious adverse event is any adverse event occurring at any dose or during any use of Merck product that: 
 
†Results in death; or 
 
†Is life threatening; or places the subject, in the view of the investigator, at immediate risk of death from the event as it occurred (Note: This does not include an 
adverse event that, had it occurred in a more severe form, might have caused death.); or 
 
†Results in a persistent or significant disability/incapacity (substantial disruption of one’s ability to conduct normal life functions); or 
 
†Results in or prolongs an existing inpatient hospitalization (hospitalization is defined as an inpatient admission, regardless of length of stay, even if the 
hospitalization is a precautionary measure for continued observation. (Note: Hospitalization [including hospitalization for an elective procedure] for a preexisting 
condition which has not worsened does not constitute a serious adverse event.); or 
 
†Is a congenital anomaly/birth defect (in offspring of subject taking the product regardless of time to diagnosis);or 
 
Is a new cancer; (that is not a condition of the study) or 
 
Is an overdose (whether accidental or intentional).  Any adverse event associated with an overdose is considered a serious adverse event. An overdose that is not 
associated with an adverse event is considered a non-serious event of clinical interest and must be reported within 24 hours. 
 
Other important medical events that may not result in death, not be life threatening, or not require hospitalization may be considered a serious adverse event when, 
based upon appropriate medical judgment, the event may jeopardize the subject and may require medical or surgical intervention to prevent one of the outcomes listed 
previously (designated above by a †). 
Duration 
Record the start and stop dates of the adverse event. If less than 1 day, indicate the appropriate length of time and units 
Action taken 
Did the adverse event cause the Merck product to be discontinued? 
Relationship to 
test drug 
Did the Merck product cause the adverse event? The determination of the likelihood that the Merck product caused the adverse event will be provided by an investigator 
who is a qualified physician. The investigator’s signed/dated initials on the source document or worksheet that supports the causality noted on the AE form, ensures 
that a medically qualified assessment of causality was done. This initialed document must be retained for the required regulatory time frame. The criteria below are 
intended as reference guidelines to assist the investigator in assessing the likelihood of a relationship between the test drug and the adverse event based upon the 
available 
information.  
The following components are to be used to assess the relationship between the Merck product and the AE; the greater the correlation with the components and 
their respective elements (in number and/or intensity), the more likely the Merck product caused the adverse event (AE): 
 
Exposure 
Is there evidence that the subject was actually exposed to the Merck product such as: reliable history, acceptable compliance assessment (pill 
count, diary, etc.), expected pharmacologic effect, or measurement of drug/metabolite in bodily specimen? 
 
Time Course 
Did 
the 
AE 
follow 
in 
a 
reasonable 
temporal 
sequence 
from 
administration 
of 
the 
Merck 
product?  
Is the time of onset of the AE compatible with a drug-induced effect (applies to trials with investigational medicinal product)? 
 
Likely Cause 
Is the AE not reasonably explained by another etiology such as underlying disease, other drug(s)/vaccine(s), or other host or environmental factors 
 
 
 
 

Product:  MK-3475 
77 
Protocol/Amendment No.:   
 
 
 
 
 
 
Relationship 
The following components are to be used to assess the relationship between the test drug and the AE: (continued) 
to 
Merck 
product 
(continued) 
Dechallenge 
Was the Merck product discontinued or dose/exposure/frequency reduced? 
If yes, did the AE resolve or improve? 
If yes, this is a positive dechallenge. If no, this is a negative dechallenge. 
(Note: This criterion is not applicable if: (1) the AE resulted in death or permanent disability; (2) the AE resolved/improved despite continuation 
of the Merck product; or (3) the trial is a single-dose drug trial); or (4) Merck product(s) is/are only used one time.) 
 
Rechallenge 
Was the subject re-exposed to the Merck product in this study? 
If yes, did the AE recur or worsen? 
If yes, this is a positive rechallenge. If no, this is a negative rechallenge. 
(Note: This criterion is not applicable if: (1) the initial AE resulted in death or permanent disability, or (2) the trial is a single-dose drug trial); or 
(3) Merck product(s) is/are used only one time). 
NOTE: IF A RECHALLENGE IS PLANNED FOR AN ADVERSE EVENT WHICH WAS SERIOUS AND WHICH MAY HAVE BEEN 
CAUSED BY THE MERCK PRODUCT, OR IF REEXPOSURE TO THE MERCK PRODUCT POSES ADDITIONAL POTENTIAL 
SIGNIFICANT RISK TO THE SUBJECT, THEN THE RECHALLENGE MUST BE APPROVED IN ADVANCE BY THE U.S. CLINICAL 
MONITOR AS PER DOSE MODIFICATION GUIDELINES IN THE PROTOCOL. 
 
Consistency with 
Trial Treatment 
Profile 
Is the clinical/pathological presentation of the AE consistent with previous knowledge regarding the Merck product or drug class pharmacology 
or toxicology? 
The assessment of relationship will be reported on the case report forms /worksheets by an investigator who is a qualified physician according to his/her best clinical judgment, including 
consideration of the above elements. 
Record one of the following 
Use the following scale of criteria as guidance (not all criteria must be present to be indicative of a Merck product relationship). 
Yes, there is a reasonable possibility 
of Merck product relationship. 
There is evidence of exposure to the Merck product.  The temporal sequence of the AE onset relative to the administration of the Merck product 
is reasonable.  The AE is more likely explained by the Merck product than by another cause. 
No, there is not a reasonable 
possibility 
Merck 
product 
relationship 
Subject did not receive the Merck product OR temporal sequence of the AE onset relative to administration of the Merck product is not reasonable 
OR there is another obvious cause of the AE.  (Also entered for a subject with overdose without an associated AE.) 

Product:  MK-3475 
78 
Protocol/Amendment No.:   
 
 
  
 
 
 
9.6.2 Definition of an Overdose for This Protocol and Reporting of Overdose to the 
Sponsor and to Merck 
For purposes of this trial, an overdose of pembrolizumab will be defined as any dose of 1,000 
mg or greater (≥5 times the indicated dose).  No specific information is available on the 
treatment of overdose of pembrolizumab. Appropriate supportive treatment should be provided 
if clinically indicated. In the event of overdose, the subject should be observed closely for signs 
of toxicity.  Appropriate supportive treatment should be provided if clinically indicated. 
 
If an adverse event(s) is associated with (“results from”) the overdose of a Merck product, the 
adverse event(s) is reported as a serious adverse event, even if no other seriousness criteria are 
met. 
 
If a dose of Merck’s product meeting the protocol definition of overdose is taken without any 
associated clinical symptoms or abnormal laboratory results, the overdose is reported as a non-
serious Event of Clinical Interest (ECI), using the terminology “accidental or intentional 
overdose without adverse effect.” 
 
All reports of overdose with and without an adverse event must be reported within 24 hours to 
the Sponsor and within 2 working days hours to Merck Global Safety (Attn: Worldwide 
Product Safety;  FAX 215 993-1220). 
 
9.6.3 Reporting of Pregnancy and Lactation to the Sponsor and to Merck 
Although pregnancy and lactation are not considered adverse events, it is the responsibility of 
investigators or their designees to report any pregnancy or lactation in a subject (spontaneously 
reported to them), including the pregnancy of a male subject's female partner that occurs during 
the trial or within 120 days of completing the trial completing the trial, or 30 days following 
cessation of treatment if the subject initiates new anticancer therapy, whichever is earlier.  All 
subjects and female partners of male subjects who become pregnant must be followed to the 
completion/termination of the pregnancy.  Pregnancy outcomes of spontaneous abortion, 
missed abortion, benign hydatidiform mole, blighted ovum, fetal death, intrauterine death, 
miscarriage and stillbirth must be reported as serious events (Important Medical Events).  If 
the pregnancy continues to term, the outcome (health of infant) must also be reported. 
 
Such events must be reported within 24 hours to the Sponsor and within 2 working days to 
Merck Global Safety (Attn: Worldwide Product Safety; FAX 215 993-1220). 
 
9.6.4 Immediate Reporting of Adverse Events to the Sponsor and to Merck 
9.6.4.1 Serious Adverse Events 
A serious adverse event is any adverse event occurring at any dose or during any use of 
Merck’s product that: 
• Results in death; 
• Is life threatening; 
• Results in persistent or significant disability/incapacity; 
• Results in or prolongs an existing inpatient hospitalization; 
• Is a congenital anomaly/birth defect; 

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• Is a new cancer (that is not a condition of the study); 
• Is associated with an overdose; 
• Is another important medical event 
 
Refer to Table 8 for additional details regarding each of the above criteria. 
 
Any serious adverse event, or follow up to a serious adverse event, including death due to any 
cause other than progression of the cancer under study that occurs to any subject from the time 
the consent is signed through 90 days following cessation of treatment, or the initiation of new 
anti-cancer therapy, whichever is earlier, whether or not related to Merck product, must be 
reported within 24 hours to the Sponsor and within 2 working days to Merck Global Safety. 
 
Non-serious Events of Clinical Interest will be forwarded to Merck Global Safety and will be 
handled in the same manner as SAEs. 
 
Additionally, any serious adverse event, considered by an investigator who is a qualified 
physician to be related to Merck product that is brought to the attention of the investigator at 
any time outside of the time period specified in the previous paragraph also must be reported 
immediately to the Sponsor and to Merck. 
 
SAE reports and any other relevant safety information are to be forwarded to the Merck 
Global Safety facsimile number:  +1-215-993-1220 
 
A copy of all 15 Day Reports and Annual Progress Reports is submitted as required by FDA, 
European Union (EU), Pharmaceutical and Medical Devices agency (PMDA) or other local 
regulators. Investigators will cross reference this submission according to local regulations to 
the Merck Investigational Compound Number (IND, CSA, etc.) at the time of submission.  
Additionally investigators will submit a copy of these reports to Merck & Co., Inc. (Attn: 
Worldwide Product Safety; FAX 215 993-1220) at the time of submission to FDA. 
 
All subjects with serious adverse events must be followed up for outcome. 
 
9.6.4.2 Events of Clinical Interest 
Selected non-serious and serious adverse events are also known as Events of Clinical Interest 
(ECI) and must be recorded as such on the Adverse Event case report forms/worksheets and 
reported within 24 hours to the Sponsor and within 2 working days to Merck Global Safety 
(Attn: Worldwide Product Safety; FAX 215 993-1220). 
 
Events of clinical interest for this trial include: 
 
1. an overdose of Merck product, as defined in Section 9.6.1 - Definition of an Overdose 
for This Protocol and Reporting of Overdose to the Sponsor, that is not associated with 
clinical symptoms or abnormal laboratory results. 
 

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2. an elevated AST or ALT lab value that is greater than or equal to 3X the upper limit of 
normal and an elevated total bilirubin lab value that is greater than or equal to 2X the 
upper limit of normal and, at the same time, an alkaline phosphatase lab value that is 
less than 2X the upper limit of normal, as determined by way of protocol-specified 
laboratory testing or unscheduled laboratory testing.* 
*Note:  These criteria are based upon available regulatory guidance documents. 
The purpose of the criteria is to specify a threshold of abnormal hepatic tests that may 
require an additional evaluation for an underlying etiology.  The trial site guidance for 
assessment and follow up of these criteria can be found in the Investigator Trial File 
Binder (or equivalent). 
 
9.6.5 Evaluating Adverse Events 
An investigator who is a qualified physician will evaluate all adverse events according to the 
NCI Common Terminology for Adverse Events (CTCAE), version 4.0. Any adverse event 
which changes CTCAE grade over the course of a given episode will have each change of 
grade recorded on the adverse event case report forms/worksheets. 
 
All adverse events regardless of CTCAE grade must also be evaluated for seriousness. 
 
10.0 STATISTICAL ANALYSIS PLAN 
Given the exploratory nature of this study, the statistical analyses will be descriptive in nature. 
For the primary and secondary objectives, sensitivity, specificity, rate of adverse event and 
distribution of best responses will be analyzed using proportions and exact 95% confidence 
intervals. Progression free survival and overall survival will be assessed using the Kaplan-
Meier product limit estimates. Outcomes in the exploratory objectives will be summarized 
using descriptive statistics as appropriate; and associations between immunological 
parameters, PDL-1 expression, clinical responses, radiological responses and other variables 
will be explored using two sample tests or correlation measures, as appropriate. 
 
Power and sample size calculation for Arm 1 
The accrual to arm 1 is stopped with 2 patients. These 2 patients will be described separately 
and no further analysis will be done.  
 
Power and sample size calculation for Arm 2 
For arm 2, we will enroll 43 GBM patients. Here we roughly estimate the precision of 
sensitivity and specificity in the primary objective based on these 43 patients. 
 
In subjects with GBM, we anticipate to have only one lesion/subject. We assume that all 
subjects will eventually have disease progression and due to dropout and inoperable cases, a 
total of n = 32 subjects will undergo surgery to provide histopathological data on disease 
progression.  Further, we assume that 40% of the n = 43 subjects will develop pseudo-
progression and be observed based on follow-up scan. 
 
For sensitivity, further assume that out of the n = 32 subjects who will undergo surgery, 26 
subjects will have true progression based on pathology (gold standard). Then based on n = 26, 

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if we observe 22 subjects (lesions) for whom the true progression is correctly identified by 
Ferumoxytol MRI, then the sensitivity will be 85% with a 95% CI between 65% and 96% 
(Table XX). 
 
Number of subjects  
(lesions) with true 
progression 
Number 
of 
subjects 
(lesions) whose true 
progression 
was 
detected 
by 
Ferumoxytol MRI 
Sensitivity 
Exact 95% CI of 
Sensitivity 
26 
26 
100% 
87% to 100% 
26 
24 
92% 
75% to 99.1% 
26 
22 
85% 
65% to 96% 
26 
20 
77% 
56% to 91% 
26 
18 
69% 
48% to 86% 
26 
16 
62% 
41% to 80% 
Table 12: Estimated sensitivity and 95% CI based on 26 subjects (lesions). 
 
For specificity, it will be calculated based on patients with pseudo-progression determined by 
either surgical results or follow-up scan. We assume that 40% of the subjects (n = 17) will 
develop pseudo-progression, then if we observe 15 subjects (lesions) for whom the pseudo-
progression status is correctly identified by ferumoxytol MRI, the specificity will be 88% with 
a 95% CI between 64% and 99% (Table 13). 
 
Number of lesions 
with 
pseudo-
progression 
Number 
of 
Lesions 
with 
pseudo-
progression detected by 
Ferumoxytol MRI 
Specificity 
Exact 95% CI of 
Specificity 
17 
17 
100% 
80% to 100% 
17 
15 
88% 
64% to 99% 
17 
13 
76% 
50% to 93% 
17 
11 
65% 
38% to 86% 
Table 13: Estimated specificity and 95% CI based on 17 patients. 
 
Statistical Analysis 
For arm 2,   sensitivity, specificity, rate of adverse events (safety and tolerability) and the 
distribution of best responses will be analyzed using proportions and exact 95% confidence 
intervals. In the primary analysis of sensitivity and specificity, the cutoff for rCBV will be 
specified as 1.75 (<1.75 is pseudoprogression and > 1.75 is progression). Analysis of 
sensitivity will be based on patients with surgical results, and specificity analysis will be based 
on patients with pseudo-progression determined based on surgical results or follow-up clinical 
scan, as detailed in the power and sample size calculation section. In secondary analysis, we 
will try other cutoff points for rCBV, and include all patients that will be confirmed with true 
progression through surgery or follow up imaging.  Progression free survival and overall 
survival will be assessed using the Kaplan-Meier product limit estimates for all patients, taking 
censoring into account. For exploratory objectives, continuous variables will be summarized 

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using mean and standard deviation, or median and range based on the distribution of data. The 
categorical variables will be summarized using frequencies and proportions, with exact 95% 
CI as appropriate. 
 
Exploratory objectives 1 to 3 will be analyzed using patients from arm 2. Immune responses 
will be determined by the volume, pattern and intensity of delayed (24hr) ferumoxytol uptake 
and compared between patients who develop true vs. pseudoprogression and provided data 
using Wilcoxon Rank Sum test (volume and intensity) or Fisher’s exact test (pattern). Systemic 
immune responses will be measured by immunological parameters (CD3, CD4, CD8, CD19, 
CD25, CD27, CD45, CD56, CD45R0, CD45RA, titers of IgD, T and T) and correlated 
with clinical responses (complete response, disease progression, pseudoprogression etc.) using 
Wilcoxon Rank Sum test, and with radiological response (size of tumor) using Pearson’s 
correlation coefficient or Spearman’s correlation coefficient. 
 
For exploratory objective 3, among the 43 patients, 8 to 10 patients are expected to have data 
on PD-1 receptor expression (Yes vs. No, where Yes is defined as >1% PDL-1 expression and 
No as < 1% based on FDA recommendations https://www.keytruda.com/static/pdf/keytruda-
pd-l1-expression-testing-guide.pdf) and immune cells (T cells, CD4+, CD8+, macrophages, 
M1, M2 etc) before initiation of Pembrolizumab and at the time of progression. If data allow, 
we will compare the PD-1 receptor expression and immune cells data before initiation of 
Pembrolizumab and at the time of progression using exact McNemar’s test or Wilcoxon signed 
test to accommodate the paired nature of the data, and use univariate logistic or Cox regression 
models to correlate PD-L1 expression with response rates and survival. Lastly, in metastatic 
patients with measurable systemic lesions, vascular volume fraction (VVF), vessel size index 
(VSI) and vessel density index (VDI) will be measured and compared between patients with 
true vs. pseudoprogression, if data allow. 
 
In summary, all these proposed analyses will be conducted on the exploratory basis. A two-
sample t-test may be used if the data show adequate normality. We will only provide 
descriptive statistics if the comparison mentioned above won’t yield clinical meaningful 
results. The purpose of these exploratory analyses is to see whether some preliminary signals 
in the data could be detected. 
 
11.0 LABELING, PACKAGING, STORAGE AND RETURN OF CLINICAL 
SUPPLIES 
Standard of Care Product 
Temozolomide will be supplied, stored, handled and distributed per package insert (section 
14.5). 
 
Investigational Products 
The investigator shall take responsibility for and shall take all steps to maintain appropriate 
records and ensure appropriate supply, storage, handling, distribution and usage of 
investigational product in accordance with the protocol and any applicable laws and 
regulations. 
 

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Clinical Supplies for pembrolizumab and ferumoxytol will be provided by Merck and AMAG 
Pharmaceuticals as summarized in Table 14. 
Table 14 Investigational Product Descriptions 
Product Name & Potency 
Dosage Form 
Investigational Drug – Merck 
1. Pembrolizumab 50 mg 
Lyophilized Powder for Injection 
2. Pembrolizumab 100 mg/4mL 
Solution for Injection 
Investigational Contrast Agent – AMAG Pharmaceuticals 
1. Ferumoxytol 510mg/17mL 
Single Dose Vial 
 
Packaging and Labeling Information 
Clinical supplies will be affixed with a clinical label in accordance with regulatory 
requirements. 
 
Clinical Supplies Disclosure 
Pembrolizumab 
This trial is open-label; therefore, the subject, the trial site personnel, the Sponsor and/or 
designee are not blinded to treatment. Drug identity (name, strength) is included in the label 
text; random code/disclosure envelopes or lists are not provided. 
 
Ferumoxytol 
Ferumoxytol is a commercially available agent and is supplied to investigators by purchasing 
through the OHSU research pharmacy. It is FDA approved for iron replacement therapy.  It is 
supplied in single dose vials containing 510 mg per 17 ml.  It is being used in this study off-
label and under a physician’s IND. 
 
Storage and Handling Requirements 
Clinical supplies must be stored in a secure, limited-access location under the storage 
conditions specified on the label. Receipt and dispensing of both agents will be recorded by 
the OHSU Research Pharmacy. Clinical supplies may not be used for any purpose other than 
that stated in the protocol. 
 
Returns and Reconciliation 
The investigator is responsible for keeping accurate records of the clinical supplies received 
from Merck or designee, the amount dispensed to and returned by the subjects and the amount 
remaining at the conclusion of the trial. 
 
Upon completion or termination of the study, all unused and/or partially used investigational 
product will be destroyed at the site per institutional policy. It is the Investigator’s 
responsibility to arrange for disposal of all empty containers, provided that procedures for 
proper disposal have been established according to applicable federal, state, local and 
institutional guidelines and procedures, and provided that appropriate records of disposal are 
kept. 
 

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12.0 ADMINISTRATIVE AND REGULATORY DETAILS 
Compliance with Trial Registration and Results Posting Requirements under the terms of the 
Food and Drug Administration Modernization Act (FDAMA) and the Food and Drug 
Administration Amendments Act (FDAAA), the Sponsor of the trial is solely responsible for 
determining whether the trial and its results are subject to the requirements for submission to 
the Clinical Trials Data Bank, http://www.clinicaltrials.gov.  Information posted will allow 
subjects to identify potentially appropriate trials for their disease conditions and pursue 
participation by calling a central contact number for further information on appropriate trial 
locations and trial site contact information. 
 
12.1 Retention of Records 
U.S. FDA regulations (21 CFR §312.62[c]) and the ICH Guideline for GCP (see Section 4.9 
of the guideline) require that records and documents pertaining to the conduct of clinical trials 
and the distribution of investigational drug, subject records, consent forms, laboratory test 
results, and medication inventory records, must be retained for 2 years after the last marketing 
application approval in an ICH region or after at least 2 years have elapsed since formal 
discontinuation of clinical development of the investigational product.  All state and local laws 
for retention of records also apply. 
 
For studies conducted outside the U.S. under a U.S. IND, the Principal Investigator must 
comply with the record retention requirements set forth in the U.S. FDA IND regulations and 
the relevant national and local health authorities, whichever is longer. 
 
12.2 Data Collection, Storage, Privacy, Confidentiality and Security 
Research charts will be maintained for each subject and housed in the offices of the PI; only 
the study staff has access to the research charts and these offices are secure, non-public spaces 
that are locked after hours, ensuring that all records will remain confidential and secure. All 
study staff is trained on the subject privacy and confidentiality policies and is up to date on all 
required research staff training. This ensures subject privacy during recruitment, consent and 
all study procedures.  
 
The Investigator is responsible for ensuring the accuracy, completeness, legibility, and 
timeliness of the data reported. All source documents should be completed in a neat, legible 
manner to ensure accurate interpretation of data. The Investigator will maintain adequate case 
histories of study participants, and source doc umentation. 
 
Data will not be released to any entity other than Merck, the IRB and the Knight Cancer 
Institute, and study personnel. No information that would reveal the identity of the subject such 
as name, social security number, address, or phone number will be disclosed. 
 
The information obtained during the conduct of this clinical study is confidential, and unless 
otherwise noted, disclosure to third parties is prohibited. Information contained within this 
study will be maintained in accordance with applicable laws protecting participant privacy, 
including the provisions of the Health Insurance Portability and Accountability Act (HIPAA). 

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Participant confidentiality is strictly held in trust by the participating Investigator(s) and study 
team. 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. 
 
 
The study monitor, other authorized representatives of the sponsor, representatives of the IRB 
or manufacturer supplying study product 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.  
 
Upon enrollment, participants will be assigned a code that will be used instead of their name, 
medical record number or other personally identifying information. Electronic files for data 
analysis will contain only the participant code. Codes will not contain any part of the 18 
HIPAA identifiers (e.g., initials, DOB, MRN). The key associating the codes and the 
participants’ personally identifying information will be restricted to the Investigator and study 
staff. The key will be kept secure on a restricted OHSU network drive a in a limited access 
folder. 
 
The study participant’s contact information will be securely stored at each 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 local IRB and institutional regulations. Study 
participant research data, which is for purposes of statistical analysis and scientific reporting, 
will be transmitted to and stored within the Knight Cancer Institute per OHSU’s Information 
Security Directives. 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 clinical sites and by Knight Cancer Institute research staff will be secured and password 
protected per OHSU’s Information Security Directives. At the end of the study, all study 
databases will be de-identified and archived within the Knight Cancer Institute. 
 
12.3 Data Storage and disposition 
The study team will maintain a password-protected database (REDCap) for subject enrollment 
and all data collection. The database (REDCap) will be maintained on an OHSU secured, 
password protected network, and only the study team will have access to the spreadsheet and 
the database, ensuring confidentiality and security of the data. Data will be kept indefinitely. 
 
If the investigator relocates or for any reason withdraws from the study, the study records must 
be transferred to an agreed upon designee, such as another institution, another investigator, or 
to OHSU Knight Cancer Institute (KCI) Clinical Trials Office. Records must be maintained 
according to sponsor or FDA requirements. 
 
Data collection is the responsibility of the clinical trial staff at the site under the supervision of 
the site Investigator. The Investigator is responsible for ensuring the accuracy, completeness, 

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legibility, and timeliness of the data reported. Standard institutional practices will be followed 
as described in the OHSU’s Information Security Directives to maintain the confidentiality 
and security of data collected in this study. Study staff will be trained with regard to these 
procedures. 
 
Loss of participant confidentiality is a risk of participation. Efforts will be made to keep study 
participant identities confidential except as required by law. Participants’ samples will be 
identified by code only. Specifically, each consenting participant will be assigned a unique 
coded identifier consisting of numbers. This identifier will be associated with the participant 
throughout the duration of their participation in the trial. The coded identifier will also be used 
to identify any participant specific samples. 
 
Basic accrual tracking information (demographic, consent, visit information) will be captured 
in OHSU’s electronic clinical information research system (eCRIS), hosted on OHSU secure 
servers and managed by OHSU’s information technology group at their data center in 
downtown Portland, Oregon. Any additional printed documents containing participant 
identifiers, such as those from the medical record to confirm eligibility, will be filed in binders 
and kept in a locked, secure location. 
 
12.4 Future Use of Stored Specimens 
Each participant who signs consent will be assigned a unique coded identifier consisting of 
numbers. This identifier will be associated with the participant throughout the duration of their 
participation in the trial. The coded identifier will be used to identify any participant specific 
samples. Blood and tissue samples collected for the purposes of this protocol will be stored 
until they can be analyzed and will then be destroyed.  
 
12.5 OHSU Knight Cancer Institute Data and Safety Monitoring Plan 
In addition to complete study and pharmacy files, complete records must be maintained on 
each subject treated on this protocol.  OHSU Knight Cancer Institute, through the auditing 
function of the Knight Clinical Trials Office, is responsible for ensuring that all member 
investigators and affiliate investigators conduct clinical research studies in compliance with 
local IRB standards, FDA regulations and NIH policies and in accordance with the Data and 
Safety Monitoring Plan policies and procedures. 
 
The study will be audited by an OHSU KCI Auditor.  Newly approved studies may be audited 
any time after enrollment has been initiated. Each OHSU Knight approved treatment protocol 
will be audited on an annual basis in accordance with the Knight Data and Safety Monitoring 
Plan. 
 
The Knight DSMC will review and monitor study progress, toxicity, safety and other data from 
this study. Information that raises any questions about participant safety or protocol 
performance will be addressed by the Investigator, statistician and study team. Should any 
major concerns arise, the Knight DSMC may recommend corrective action and determine 
whether or not to suspend the study. 
 

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The Knight DSMC will review each protocol every 6 months, but may occur more often, if 
required, to review toxicity and accrual data (please refer to Knight DSMP for additional 
details on audit frequency). The Knight DSMC will review accrual, toxicity, response and 
reporting information. Information to be provided to the DSMC may include: participant 
accrual; treatment regimen information; AEs and SAEs reported by category; summary of any 
deaths on study; audit results; and a summary provided by the study team. Other information 
(e.g. scans, laboratory values) will be provided upon request.  
 
12.6 Clinical Data & Safety Monitoring 
Monitoring visits will be performed during the study to ensure that the rights and well-being 
of human participants are protected, that the reported trial data are accurate, and that the 
conduct of the trial is in compliance with the protocol, GCP, and applicable regulatory 
requirements.  
 
Details of monitoring activities, including designation of assigned monitoring entities, scope 
of monitoring visits, timing, frequency, duration of visits, and visit reporting, will be included 
in a separate trial-specific monitoring plan (TSMP). 
 
The Investigator agrees that the monitor will be permitted to conduct monitoring visits at 
appropriate intervals. The Investigator agrees to provide all relevant information and 
documentation as requested by the monitor, including access to all original study documents 
and source data, including access to electronic medical records and/or source documents if 
necessary. 
 
The monitor will conduct source data review and verification as outlined in the TSMP, and 
following each visit will generate a report summarizing the visit findings. 
 
Regardless of monitoring entity, the OHSU Sponsor-investigator is ultimately, singularly 
responsible for overseeing every aspect of the design, conduct, and final analysis of his/her 
investigation. 
 
If at any time Investigator noncompliance is discovered at OHSU, the Sponsor-investigator 
shall promptly either secure compliance or end the Investigator’s participation in the study. 
 
Independent audits may be conducted by the Knight DSMC to verify that the rights and well-
being of human participants are protected, that the reported trial data are accurate, that the 
conduct of the trial is in compliance with the protocol and applicable regulatory requirements, 
that monitoring practices are adequate and in compliance with the monitoring plan, and that 
evidence of ongoing investigator oversight is present. 
 
12.7 
Quality Assurance & Quality Control 
The investigational site will provide direct access to all trial related source data/documents, 
and reports for the purpose of monitoring by the monitor and/or sponsor, and auditing by the 
Knight DSMC and/or regulatory authorities.  
 

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Quality assurance (QA) auditing activities will occur as detailed in the Knight DSMP. All 
discrepancies, queries, deviations, observations, and findings will be compiled into a final audit 
report along with a Corrective and Preventative Action Plan. 
 
The Sponsor-investigator, or study monitor, will verify that the clinical trial is conducted and 
data are generated, documented (recorded), and reported in compliance with the protocol, 
GCP, and the applicable regulatory requirements (e.g., Good Laboratory Practices (GLP), 
Good Manufacturing Practices (GMP)). 
 
13.0 ETHICS/PROTECTION OF HUMAN PARTICIPANTS 
13.1 Ethical Standard 
The Investigator will ensure that this study is conducted in full conformity with Regulations 
for the Protection of Human Participants of Research codified in 45 CFR Part 46, 21 CFR Part 
50, 21 CFR Part 56, 21 CFR 312 (for IND studies), 21 CFR 812 (for IDE studies), and/or the 
ICH E6. 
 
13.2 Institutional Review Board  
The protocol, informed consent form(s), recruitment materials, and all participant materials 
will be submitted to the 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. All changes to the consent form will be IRB approved; a determination will be made 
regarding whether previously consented participants need to be re-consented. 
 
13.3 Informed Consent 
Written informed consent will be obtained from all participants participating in this trial, as 
stated in the Informed Consent section of 21 CFR Part 50. Documentation of the consent 
process and a copy of the signed consent shall be maintained in the participant’s medical 
record.  
 
Informed consent is a process that is initiated prior to the individual’s agreement to participate 
in the study and continues throughout the individual’s study participation. Extensive discussion 
of risks and possible benefits of participation will be provided to the participants and their 
families as appropriate. Consent forms will be IRB-approved and the participant will be asked 
to read and review the document. The Investigator will explain the research study to the 
participant and answer any questions that may arise. All participants will receive a verbal 
explanation in terms suited to their comprehension of the purposes, procedures, and potential 
risks/benefits of the study, alternatives to participation, and of their rights as research 
participants. Participants will have the opportunity to carefully review the written consent form 
and ask questions prior to signing. The participants should have the opportunity to discuss the 
study with their surrogates or think about it prior to agreeing to participate. The participant will 
sign the informed consent document prior to any procedures being done specifically for the 
study. The participants may withdraw consent at any time throughout the course of the trial. A 
copy of the informed consent document will be given to the participants for their records. The 

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rights and welfare of the participants will be protected by emphasizing to them that the quality 
of their medical care will not be adversely affected if they decline to participate in this study. 
 
13.4 Protocol Review  
The protocol and informed consent form for this study must be reviewed and approved in 
writing by the OHSU Knight Cancer Institute’s Clinical Research Review Committee (CRRC) 
and the appropriate IRB prior to any participant being consented on this study.   
 
13.5 Changes to Protocol 
Any modification of this protocol must be documented in the form of a protocol revision or 
amendment submitted by the Investigator and approved by the CRRC and IRB, before the 
revision or amendment may be implemented.  The only circumstance in which the amendment 
may be initiated without regulatory approval is for a change necessary to eliminate an apparent 
and immediate hazard to the participant.  In that event, the Investigator must notify the IRB 
(and sponsor/FDA if under an IND/IDE) within 5 business days after the implementation.  
 
An Investigator who holds an IND or IDE application must also notify the FDA of changes to 
the protocol per 21 CFR 312 or 21 CFR 812, respectively. 
 
14.0 
INCLUSION OF WOMEN, MINORITIES AND CHILDREN IN CLINICAL 
TRIALS 
The following protocol attachment is required by the OHSU Knight Cancer Institute, Clinical 
Research Review Committee in order to meet NIH guidelines on the inclusion of women, 
minorities and children as subjects in clinical research. This policy conforms to section 492B of 
the Public Health Service Act, NIH Revitalization Act of 1993, and Public Law 103-43. 
No OHSU Knight Cancer Institute study will focus on any particular gender, racial or ethnic 
subset. No subject will be excluded from the study on the basis of gender, racial or ethnic origin. 
Male, female and minority volunteers will be recruited for this study from the general population 
and approximately 50% men and 50% women will be studied. Gender-nonconforming and gender-
fluid individuals as members of the general population will also be recruited. 
 
The projected gender, racial, and ethnic composition of the study will represent that of the state of 
Oregon.  
 
Table 15: Population Demographics - Oregon (%) 
Ethnic Category 
Sex/Gender 
Females 
Males 
Total 
Hispanic or Latino 
 
 
11.7 
Not Hispanic or Latino 
 
 
88.3 
Ethnic 
Category: 
Total 
of 
all 
subjects* 
 
 
100* 
Racial Category 
 

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Source:   U.S. Census Bureau, 2010    *Totals may not equal 100 due to rounding. 
 
Table 16: Projected Accrual 
Ethnic Category 
Sex/Gender 
Females 
Males 
Unknown 
Total 
Hispanic or Latino 
3 
2 
 
5 
Not Hispanic or Latino 
20 
20 
 
40 
Unknown 
 
 
 
 
Ethnic Category: Total of all 
subjects* 
23 
22 
 
45 
Racial Category 
 
American Indian or Alaskan Native  
 
 
 
Asian 
1 
1 
 
2 
Black or African American 
1 
 
 
1 
Native Hawaiian or other Pacific 
Islander 
 
 
 
 
White 
19 
19 
 
38 
More than one race 
1 
1 
 
2 
Unknown 
1 
1 
 
2 
Racial Category: Total of all 
subjects* 
23 
22 
 
45 
Source:   Adapted from U.S. Census Bureau, 2010 *Totals may not equal 100 due to 
rounding. 
Ethnic Category 
Sex/Gender 
Females 
Males 
Total 
American Indian or Alaskan Native 
 
 
1.4 
Asian 
 
 
3.7 
Black or African American 
 
 
1.8 
Native Hawaiian or other Pacific 
Islander 
 
 
0.3 
White 
 
 
83.6 
More than one race 
 
 
3.8 
Unknown/Other 
 
 
5.3 
Racial 
Category: 
Total 
of 
all 
subjects* 
 
 
100* 
TOTALS 
50.4 
49.6 
100* 

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Inclusion of Children 
In accordance with NIH guidelines on the inclusion of children as participants in research 
involving human subjects, children under the age of 18 years must be included in all human 
subjects’ research, conducted or supported by the NIH, unless there are clear and compelling 
reasons not to include them. Therefore, proposals for research involving human subjects must 
include a description of plans for the inclusion of children. 
 
This protocol does not include children for the following reason: No dosing or adverse event 
data are currently available on the use of this Study Agent in this way in subjects <18 years of 
age. Therefore, children are excluded from this study but will be eligible for future pediatric 
trials with this Study Agent. 
 
15.0 SUPPLEMENTAL MATERIAL 
15.1 ECOG Performance Status 
Grade 
Description 
0 
Normal activity. Fully active, able to carry on all pre-disease 
performance without restriction. 
1 
Symptoms, but ambulatory. Restricted in physically strenuous 
activity, but ambulatory and able to carry out work of a light or 
sedentary nature (e.g., light housework, office work). 
2 
In bed <50% of the time. Ambulatory and capable of all self-care, but 
unable to carry out any work activities. Up and about more than 50% 
of waking hours. 
3 
In bed >50% of the time. Capable of only limited self-care, confined 
to bed or chair more than 50% of waking hours. 
4 
100% bedridden. Completely disabled. Cannot carry on any self-care. 
Totally confined to bed or chair. 
5 
Dead. 
* 
As published in Am. J. Clin. Oncol.:  Oken, M.M., Creech, R.H., Tormey, D.C., 
Horton, J., Davis, T.E., McFadden, E.T., Carbone, P.P.: Toxicity And Response Criteria 
Of The Eastern Cooperative Oncology Group. Am J Clin Oncol 5:649-655, 1982. The 
Eastern Cooperative Oncology Group, Robert Comis M.D., Group Chair. 
 
15.2 Common Terminology Criteria for Adverse Events V4.0 (CTCAE) 
The descriptions and grading scales found in the revised NCI Common Terminology Criteria 
for Adverse Events (CTCAE) version 4.0 will be utilized for adverse event reporting. 
(http://ctep.cancer.gov/reporting/ctc.html) 
 
 
15.3 Ferumoxytol Investigator’s Brochure 
 
15.4 Pembrolizumab Package insert 
 

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15.5 Temozolomide Package Insert  
 
16.0 APPENDICES 
 
Appendix A: Ferumoxytol Adverse Events Form 
Appendix B: Pembrolizumab Adverse Events Form 
 
 
 
 

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patients 
with 
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nervous 
system 
neoplasms 
using 
ferumoxytol, 
a 

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superparamagnetic iron oxide nanoparticle. J Cereb Blood Flow Metab, 2013. 33(5): 
p. 780-6. 
91. 
Gahramanov, S., et al., Pseudoprogression of glioblastoma after chemo- and radiation 
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survival. Radiology, 2013. 266(3): p. 842-52. 
92. 
Wolchok, J.D., et al., Guidelines for the evaluation of immune therapy activity in solid 
tumors: immune-related response criteria. Clin Cancer Res, 2009. 15(23): p. 7412-20.