Phase 1, Open Label Trial to Evaluate the Safety and Immunogenicity of PAN-301-1 in Cancer Patients
Phase: PHASE1
Conditions: Prostate Cancer
Sponsor: Sensei Biotherapeutics, Inc.

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PHASE I, OPEN-LABEL TRIAL TO EVALUATE THE SAFETY AND 
IMMUNOGENICITY OF SNS-301 IN CANCER PATIENTS   
 
 
Study product:  
SNS-301 
Protocol number:  
SNS0216 
IND:                               16963 
Phase:  
1 
Version:  
5.0 
Amendment Date:  
12 June 2018  
      Study Sponsor: 
        Sensei Biotherapeutics, Inc. 
620 Professional Drive 
 
Gaithersburg, MD 20879 
Regulatory Statement 
This study will be performed in compliance with the protocol and in accordance with Good Clinical 
Practice (International Conference on Harmonization, Guidance E6, 1996), principles of human 
subject protection, and applicable country-specific regulatory requirements. 
Confidentiality Statement 
The information in this document contains trade secrets and commercial information that are 
privileged or confidential and may not be disclosed unless such disclosure is required by applicable 
laws and regulations. In any event, persons for whom this information is disclosed must be 
informed that the information is privileged or confidential and may not be further disclosed by 
them. These restrictions on disclosure will apply equally to all future information supplied to you 
that is indicated as privileged or confidential. 
This Study Protocol is produced on a word-processing system and bears no signatures. The 
approval of the Study Protocol is documented in a separate Approval Document.  

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SPONSORS PROTOCOL SIGNATURE PAGE 
 
 
Sponsor: 
Sensei Biotherapeutics, Inc. 
Protocol Title 
Phase I, Open-Label Trial To Evaluate The Safety And Immunogenicity 
Of SNS-3011 In Cancer Patients 
Protocol Number 
SNS0216 
Protocol Version 
Amendment Date:  
Version 5.0 
12 June 2018 
 
 
I approved the protocol and confirm that the protocol follows the current ICH/GCP guidelines. 
 
 
 
 
_______________________________________________________________________________ 
Steve Fuller, Ph.D. 
 
Date 
Chief Operating Officer 
Sensei Biotherapeutics, Inc. 
 
 
                                                     
1 Due to the company changing their name from Panacea Pharmaceuticals to Sensei Biotherapeutics, the 
drug PAN-301-1 was renamed SNS-301. 

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TABLE OF CONTENTS 
1. 
SYNOPSIS ................................................................................................................................. 6 
1.1 
TIME AND EVENTS SCHEDULES ............................................................................... 13 
2. 
TERMS, ACRONYMS, ABBREVIATIONS ....................................................................... 15 
3. 
INTRODUCTION .................................................................................................................. 17 
3.1 
PRIMARY DISEASE AND STUDY TREATMENT INFORMATION ........................................... 17 
3.2 
PREVIOUS NON-CLINICAL EXPERIENCE ........................................................................... 18 
3.3 
CURRENT CLINICAL EXPERIENCE ..................................................................................... 19 
3.4 
STUDY RATIONALE ........................................................................................................... 21 
4. 
STUDY OBJECTIVES AND ENDPOINTS ......................................................................... 22 
4.1 
STUDY OBJECTIVES .......................................................................................................... 22 
4.1.1 
Primary ..................................................................................................................... 22 
4.1.2 
Secondary ................................................................................................................. 22 
4.2 
STUDY ENDPOINTS ............................................................................................................ 23 
4.2.1 
Primary ..................................................................................................................... 23 
4.2.2 
Secondary ................................................................................................................. 23 
4.2.3 
Clinical secondary endpoints .................................................................................... 23 
4.2.4 
Pharmacodynamic secondary endpoints .................................................................. 23 
5. 
INVESTIGATIONAL PLAN ................................................................................................ 24 
5.1 
OVERALL STUDY DESIGN AND PLAN DESCRIPTION ......................................................... 24 
5.2 
SELECTION OF STUDY POPULATION ................................................................................. 26 
5.2.1 
Inclusion Criteria ...................................................................................................... 26 
5.2.2 
Exclusion Criteria ..................................................................................................... 26 
5.2.3 
Removal of Patients from Treatment or Assessment ................................................. 27 
5.2.4 
Enrollment Holds ...................................................................................................... 28 
5.3 
STUDY TREATMENT .......................................................................................................... 28 
5.3.1 
Treatments Administered .......................................................................................... 28 
5.3.2 
Identity of the Study Treatment ................................................................................. 28 
5.3.2.1 
Study Treatment Details .................................................................................... 28 
5.3.2.2 
Study Treatment Administration ...................................................................... 28 
5.3.2.3 
Handling and Storage of Study Treatment ...................................................... 28 
5.3.2.4 
Handling/Responsibilities ................................................................................... 29 
5.3.2.5 
Study Investigational Treatment Management and Disposal ......................... 29 
5.3.3 
Method of Assigning Patients to Study Groups ........................................................ 29 
5.3.4 
Selection of Doses for the Study ............................................................................... 30 
5.3.5 
Selection and Timing of Dose for Each Patient ........................................................ 30 
5.3.5.1 
Dose-limiting toxicities ....................................................................................... 31 
5.3.5.2 
Dose delay or reduction ...................................................................................... 31 
5.4 
BLINDING .......................................................................................................................... 31 
5.4.1 
Prior and Concomitant Treatment ............................................................................ 31 
5.4.1.1 
Allowed concomitant treatments ....................................................................... 31 
5.4.1.2 
Prohibited Medications or Treatments During Study ..................................... 32 
5.4.2 
Study Treatment Accountability and Compliance Procedures ................................. 32 
5.5 
SAFETY AND EFFICACY VARIABLES AND STUDY ASSESSMENTS ..................................... 32 

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5.5.1 
Pre-study Assessments .............................................................................................. 32 
5.5.1.1 
HAAH expression of archived tissue ................................................................. 32 
5.5.1.2 
HAAH expression in serum ............................................................................... 32 
5.5.2 
Study visits and assessments ..................................................................................... 32 
5.5.2.1 
Screening period (Day -56 (+ 7 days) to Day 0) ................................................ 32 
5.5.2.2 
Dose-escalation Treatment: Day 1 ..................................................................... 33 
5.5.2.3 
Dose-escalation Treatment: Day 8 ± 2 days ...................................................... 33 
5.5.2.4 
Dose-escalation Treatment: Day 15 ± 2 days .................................................... 33 
5.5.2.5 
Study Visits: Day 22, Day 43 ± 3 days ............................................................... 33 
5.5.2.6 
Additional treatment: Every additional 21 days ± 3 days if indicated ........... 34 
5.5.2.7 
Follow up and End of Study (EOS): 28 days ± 3 days after last treatment for 
a total of 6 months ............................................................................................................... 34 
5.5.3 
Safety Measurements ................................................................................................ 34 
5.5.3.1 
Clinical Laboratory Assessments ...................................................................... 34 
5.5.3.2 
Immunological blood collection ......................................................................... 35 
5.5.3.3 
Administration site reaction .............................................................................. 36 
5.5.3.4 
ECOG performance score .................................................................................. 36 
5.5.3.5 
Adverse Events (AE) ........................................................................................... 36 
5.5.3.6 
Serious Adverse Event (SAE) ............................................................................ 38 
5.5.3.7 
Unexpected fatal or life-threatening suspected adverse reaction reports ...... 39 
5.5.3.8 
Clinical Laboratory Assessments ...................................................................... 39 
5.5.4 
Efficacy (Clinical) Measurements............................................................................. 40 
5.5.4.1 
PSA assessment ................................................................................................... 40 
5.5.4.2 
Treatment Failure ............................................................................................... 40 
5.6 
DATA QUALITY ASSURANCE ............................................................................................ 40 
6. 
STATISTICAL METHODS AND DETERMINATION OF SAMPLE SIZE .................. 40 
6.1 
STATISTICAL AND ANALYTICAL PLANS ........................................................................... 40 
6.2 
DETERMINATION OF SAMPLE SIZE .................................................................................... 40 
7. 
ETHICS ................................................................................................................................... 40 
7.1 
INSTITUTIONAL REVIEW BOARD (IRB) / ETHICS COMMITTEE ......................................... 40 
7.2 
ETHICAL CONDUCT OF THE STUDY ................................................................................... 41 
7.3 
PATIENT INFORMATION AND CONSENT ............................................................................ 41 
7.4 
PROTOCOL AMENDMENTS ................................................................................................ 41 
7.5 
CONFIDENTIALITY ............................................................................................................ 41 
8. 
INVESTIGATORS AND STUDY ADMINISTRATIVE STRUCTURE .......................... 42 
8.1 
SPONSOR CONTACTS ......................................................................................................... 42 
8.2 
DATA HANDLING AND RECORDKEEPING .......................................................................... 42 
8.2.1 
Electronic Case Report Form (eCRF) ...................................................................... 42 
8.2.2 
Maintenance of Study Records ................................................................................. 42 
8.3 
FINAL REPORT .................................................................................................................. 42 
8.4 
PUBLICATION AND USE OF STUDY FINDINGS ................................................................... 43 
8.5 
LIABILITY AND INSURANCE .............................................................................................. 43 
9. 
REFERENCE LIST ................................................................................................................ 44 
10. LIST OF APPENDICES ........................................................................................................ 45 

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APPENDIX A: ECOG PERFORMANCE STATUS ................................................................... 46 
APPENDIX B: PRINCIPAL INVESTIGATOR SIGNATURE OF AGREEMENT PAGE ... 47 
 
 
 

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1. SYNOPSIS 
Protocol number: 
SNS0216 
Protocol title: 
Phase I, Open-Label Trial to Evaluate the Safety and Immunogenicity of 
SNS-301 in Cancer Patients 
Phase of development: 
Phase I 
Objectives (Part 1): 
Primary   
To determine the maximum tolerated dose (MTD) of SNS-301, based on the 
incidence of dose limiting toxicities (DLT) and the maximum administered 
dose of SNS-301, when administered every 21 days in patients with 
biochemically relapsed prostate cancer. 
 
Secondary 
To assess the overall safety of SNS-301.  
Study design: 
This is a Phase I, open-label, study of SNS-301, an HAAH-directed 
nanoparticle vaccine, given intradermally in cohorts of patients with 
biochemically relapsed prostate cancer, using a fixed dose-escalation schema 
every 21 days to establish the MTD.  
Following informed consent and screening, archived prostate tumor tissue 
(if available), and patient fresh serum will be tested for the expression of 
HAAH. Patients who test positive for HAAH expression in either archived 
tumor tissue (if available), or fresh serum may be continued in the study. 
Baseline biochemical testing (chemistry, complete blood count [CBC], 
coagulation panel, CH-50, and prostate-specific antigen [PSA],) will be 
obtained prior to study treatment.  Patients who are negative for HAAH in 
archived tumor tissue or fresh serum can be followed for PSA levels over 
the next 6 months, and, if levels increase appreciably, they can be retested 
for HAAH. If HAAH is positive at any time within the 6-month period, the 
patient can be enrolled.  
Treatment will consist of single repeated doses of SNS-301 administered 
every 21 days for 3 doses. A traditional 3+3 dose-escalation schema will be 
used to determine the MTD of SNS-301for the first 2 doses and a modified 
dose-escalation schema for the remaining dose. Planned doses of SNS-301 
are 2.0 x 1010, 1.0 x 1011 and 3.0 x 1011 particles per administration diluted 
to 1 mL and administered intradermally.  Additional patients will be 
enrolled at the highest dose level until at least 6 patients can be evaluated 
even if no DLTs are observed at the dose. Planned treatment may continue 
for two additional doses of SNS-301 administered every 21 days.  Serum 
and whole blood samples will be obtained on the day of study treatment, at 
Day 1, Day 8, Day 15, and Day 22 during the first cycle. For patients who 
continue to receive study treatment, biochemical and immunologic testing 
will continue every 21 days.  
The MTD will be determined over the first 21-day interval following a 
single dose of SNS-301 in 3 dose cohorts. The MTD will be considered the 
dose level lower than the dose producing ≥2 DLTs in 3-6 patients. Patients 
who withdraw in cycle 1 for reasons other than safety or toxicity will be 
replaced. Any of the following, if judged to be associated with SNS-301 

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(i.e., possibly-, probably-, or definitely related to), will be considered a DLT 
using the National Cancer Institute-Common Terminology Criteria for 
Adverse Events (NCI-CTCAE) Version 4.03: 
1) Grade 4 non-hematological toxicities (excluding alopecia) of any 
duration 
2) Grade 3 non-hematologic (non-laboratory) toxicity lasting > 3 days 
despite optimal supportive care  
3) Any Grade 3 or Grade 4 non-hematologic laboratory value if: a). 
Medical intervention is required to treat the patient; b), the 
abnormality leads to hospitalization; c). The abnormality persists for 
>1 week.  
4) Grade 4 hematologic toxicity, other than those specified in criteria 5 
and 6 below, lasting > 7 days 
5) Grade 3 or Grade 4 febrile neutropenia of any duration 
6) Grade 3 thrombocytopenia in combination with a grade 3 or greater 
blood and lymphatic system disorder 
7) Grade 3 AST or ALT that is associated with a grade 2 rise in bilirubin 
The recommended Phase 2 dose (RP2D) will be defined as the highest dose 
administered if no MTD is observed.  
Dose cohorts will be enrolled sequentially and no dose escalation will occur 
until all patients in the current cohort complete the first 21-day cycle. After 
the first patient in each cohort has demonstrated adequate safety and 
tolerability for at least 21 days, the next 2 patients in the cohort may be 
enrolled. When at least 3 patients have reached Day 21 if none of the first 3 
patients experiences a DLT, then dose-escalation to the next level can begin.  
Multiple patients can be in the screening phase but the first eligible patient 
able to be treated is assigned the treatment slot that is available for study.  
A safety assessment of administration site reactions (ASR) will be made by 
the Investigator at least 30 minutes (or later) following each dose of study 
drug using the (NCI-CTCAE V4.03). Enrollment will be held if an ASR of 
grade 3 or greater (NCI-CTCAE V4.03) is observed, until the event resolves. 
In the event enrollment is held for an ASR, the Sponsor and Investigator will 
evaluate the outcome of the ASR and must agree to continued enrollment.  
In patients who tolerate SNS-301, additional treatment may be continued 
with single doses of SNS-301 at their current dose level, to maintain 
geometric mean titer (GMT) of HAAH antibodies to no less than 4 times the 
baseline value for at least six months (9 injections). Treatment will be 
terminated with the 9th injection or will otherwise be terminated at any time 
upon the observance of PSA doubling < 90 days or occurrence of 
unacceptable toxicity. After termination, patients will be followed for an 
additional 6 months with monthly PSA levels and imaging studies as needed. 
If an unacceptable rise is detected in the patient’s PSA levels following 
treatment discontinuation, patients shall be eligible for immediate 
resumption of therapy.  

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Once the MTD/RP2D is determined, patients receiving ongoing treatment 
may be escalated to that dose for subsequent treatments. These patients will 
continue to be followed for safety and biochemical PSA monitoring. 
Pharmacodynamics:  
Exploratory pharmacodynamic (PD) analysis will be performed using dose, 
vaccine-specific antibody response (geometric mean of titer), antigen-
specific T and B cell indices, and the relative expression of HAAH in each 
patient’s tumor. The PD will be balanced and optimized to the degree of 
antigen-specific immune response and minimized for the production of 
regulatory immune processes.  
Other Safety:  
Safety will be evaluated by the incidence and severity of ASRs, changes in 
biochemical safety measures, general incidence and types of AEs, serious 
adverse events (SAEs), and other overt toxicities. 
Number of patients/ 
centers:  
This is a multi-center dose-escalation study with an extension study at the 
RP2D. Up to approximately 18 patients will be studied. 
Randomization 
procedure: 
The study is an open-label, dose-escalating, non-randomized Phase 1 clinical 
study with a dose extension phase. No randomization will be performed.  
Inclusion criteria: 
1. 
Signed and dated written Ethics Committee approved informed consent 
2. 
Men aged 21 to 85 years with a histologic diagnosis of prostate cancer 
with a biochemical relapse following definitive local therapy (RP or 
radiation therapy) 
3. 
Patients are not eligible or are unwilling to receive additional definitive 
therapy following relapse (either RP or radiation therapy)  
4. 
No prior cytotoxic chemotherapy for the current cancer 
5. 
Normal electrocardiogram (ECG) or ECG with no clinically significant 
findings as determined by the Principal Investigator 
6. 
Presence of biochemically relapsed prostate cancer defined as either: 
1) PSA > 2 ng/mL 1 year following initial definitive treatment for 
prostate cancer: or, 2) PSA doubling time (greater than 0.2 ng/mL)  
< 12 months; or, 3) PSA velocity > 2 ng/mL/year at any time following 
radical prostatectomy or radiation therapy.  
7. 
Positive expression of HAAH in either archived tumor tissue (if 
available) or fresh serum 
8. 
No clinical or radiologic evidence of distant metastatic disease as 
measured by pelvic MRI or CT scan in addition to bone scan. These 
studies will need to be performed within 56+7 days prior to the start of 
the study. 
9. 
No history of immunosuppressive disease. Active autoimmune disease 
is defined as any disease process that has specifically needed 
administration of immune suppressive and or cytoreductive therapy 
currently or within the last 1 year. 
10. No evidence of active autoimmune disease 
11. Able and willing to comply with all study procedures 
 
 

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Exclusion criteria: 
1. 
PSA doubling time of < 3 months 
2. 
Participation in a clinical trial within 30 days of prior to enrollment 
3. 
Prior major surgery or radiation therapy within 4 weeks of enrollment 
4. 
Any illness or condition that in the opinion of the Investigator may 
affect the safety of the subject or the evaluation of any study endpoint 
5. 
Screening blood counts of the following:  
Hematopoietic:  
Absolute neutrophil count < 1500/μL,  
Platelets < 100,000/μL,  
Hemoglobin < 9 g/dL; 
Liver/Metabolic:  
Alanine aminotransferase (ALT) and aspartate 
transaminase (AST) > 2.5 × ULN range,  
Total bilirubin > 2 × ULN,  
Albumin < 2.8 g/dL; 
Renal:  
Creatinine clearance < 50 mL/min as predicted by the 
Cockcroft-Gault formula 
6. 
Subjects whose partners are women of child-bearing potential 
(WOCBP) must use an adequate method of birth control while on study 
drug and at least for 3 weeks after discontinuation of study drug 
7. 
Current or anticipated concomitant immunosuppressive therapy 
(excluding 
non-systemic 
inhaled, 
topical 
skin 
and/or 
eye 
drop-containing corticosteroids) 
8. 
Any concurrent condition requiring the continued use of systemic 
steroids (see above) or the use of immunosuppressive agents including 
methotrexate. All other systemic corticosteroids must be discontinued 
at least 4 weeks prior to first study treatment 
9. 
Receipt of any blood product within 1 month of enrollment 
10. Receipt of any vaccine within 4 weeks of enrollment 
11. Active drug or alcohol use or dependence that, in the opinion of the 
Investigator, would interfere with adherence to study requirements 
12. Been imprisoned or compulsorily detained (involuntarily incarcerated) 
for treatment of either a psychiatric or physical (i.e. infectious disease) 
illness 
13. Patients who have a history of coagulopathies, thrombosis or 
who are receiving active anticoagulation for any condition, such 
as but not limited to, artificial heart valves, atrial fibrillation, etc.  
14. Any other conditions judged by the Investigator that would limit 
the evaluation of a subject 
Study Product 
Formulation 
SNS-301 consists of lambda bacteriophages expressing HAAH-1λ on the 
head of the bacteriophage. The bacteriophages are prepared in a liquid 
formulation in phosphate-buffered saline, pH 7.4.  A 1mL dose filled in a 
3M® glass cartridge with a butyl rubber stopper and crimp cap seal.   

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Route of 
administration: 
Intradermally: vaccine to be delivered by a single-use 3M® hollow micro 
structured transdermal system (hMTS) device. 
Dose regimen: 
Escalating doses of 2.0 x 1010 and 1.0 x 1011 particles will be administered to 
cohorts of 3 patients and 3.0 x 1011 particles will be administered to a cohort 
of 6 patients every 21 days to assess the MTD.  The RP2D will be considered 
the MTD unless convincing safety, PD, or PK data suggest otherwise. At 
such a point, these data will be shared with the FDA and the RP2D will be 
changed or additional dose escalation cohorts will be proposed If needed. 
Additional patients will be enrolled at the highest dose level until at least 6 
patients can be evaluated even if no DLTs are observed at the dose.  
Patients in the dose-escalation phase may continue to receive single doses of 
SNS-301 at their original dose level every 21 days or until the PSA doubling 
is < 90 days or unacceptable toxicity as determined by the Principal 
Investigator is observed (either for that patient or in their dose cohort). Once 
the MTD/RP2D is determined, patients receiving ongoing treatment may be 
escalated to that dose for subsequent treatments and receive a maximum of 
9 injections.  Patients who have received more than 9 injections due to the 
timing of the amendment limiting therapy to 6 months (9 doses), will be 
stopped at their last dose received and be followed for 6 months as with other 
patients.  These subjects will continue to be followed for safety and 
biochemical PSA monitoring on a monthly basis for 6 months and are 
eligible to resume SNS-301 in case of increases in PSA doubling to < 90 
days or other evidence of disease progression and decline in immunological 
parameters.  
Study Endpoints: 
Primary endpoint: 
• 
To determine the MTD 
• 
Determine the RP2D if different than the MTD 
• 
Determine the DLTs associated with SNS-301 
Secondary endpoints: 
• 
Incidence of administration site reactions 
• 
Biochemical safety and tolerability 
• 
Geometric mean titers of anti-HAAH antibodies by dose 
• 
Antigen-specific CTL responses by dose 
• 
Production of B cell and T cell response of interest  
Clinical secondary endpoints:  
• 
Change in the PSA velocity  
• 
Reduction in the PSA doubling time from pre-baseline 
Pharmacodynamic secondary endpoints:  
• 
Duration of antigen-specific anti-HAAH antibody titers 
• 
Changes in the amplitude or duration of the production of 
anti-HAAH antibodies 
• 
Correlation of anti-HAAH titers and serum HAAH levels  
Study evaluations: 
Following informed consent signature, archived prostate tumor tissue, and 
patient serum will be tested for the expression of HAAH.  Only patients who 
test positive for HAAH expression in archived tumor tissue (if available) or 
fresh serum may be continued in the study.  
The following evaluations will be performed: 
• 
Medical/oncology history, demographics: Screening 

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• 
Signs and symptoms (baseline): Screening, Day 1 
• 
Physical examination: Screening and end of study (EOS) 
• 
Symptom-directed physical examination: Day 1, Day 8, Day 15, Day 
22, Day 43 and if additional treatment is given, at 21-day intervals 
thereafter   
• 
Biochemical testing (chemistry, CBC, coagulation, CH50): 
Screening, Day 1, Day 22, Day 43 and if additional treatment is 
given at 21-day intervals thereafter and EOS 
• 
Biochemical testing (chemistry, CBC, coagulation, CH50) Day 8 
and Day 15 during cycle 1 
• 
Study treatment administration: Day 1, Day 22, Day 43 and if 
additional treatment is given, at 21-day intervals thereafter for a total 
of 9 injections.  Patients who have received more than 9 injections 
due to the timing of the amendment that details limiting therapy to 
6 months (9 doses), will be stopped at their last dose received and be 
followed for 6 months as with other patients.  Patients with off-
treatment evidence of progression and declining HAAH immune 
parameters during the 6-month observation period will have the 
option of immediately resuming therapy on study protocol. 
• 
Physician administration site assessment: Day 1, Day 8, Day 22, 
Day 43 and if additional treatment is given at 21-day intervals 
thereafter; and EOS 
• 
Safety evaluation of subject to permit continued enrollment in each 
cohort Day 21for every first and last patient in a dose level 
• 
Eastern Cooperative Oncology Group (ECOG) performance score: 
Screening, Day 1, Day 8, Day 15, Day 22, Day 43 and if additional 
treatment is given, at 21-day intervals thereafter; and EOS 
• 
Prostate-specific antigen (PSA) assessment: Screening, Day 1, 
Day 22, Day 43 and if additional treatment is given, at 21 day 
intervals thereafter; until injection number 9 (or last dose otherwise) 
and EOS.  Afterwards PSA levels will be obtained on a monthly 
basis for a total of 6 months.  
• 
Immunologic blood collection: Screening, Day 1, Day 22, Day 43 
and if additional treatment is given, at 21 day intervals thereafter; 
until injection number 9 (or last dose otherwise) and EOS. 
Afterwards levels will be obtained on a monthly basis for a total of 
6 months.  
• 
Adverse events and concomitant medications (after the patient 
receives study drug): Screening, Day 1, Day 8, Day 15, Day 22, 
Day 43 and if additional treatment is given, at 21 day intervals 
thereafter; until injection number 9 (or last dose otherwise) and EOS. 
Afterwards history will be obtained on a monthly basis for a total of 
6 months. 
• 
Vital signs, ECG: Screening, Day 1, Day 22, Day 43 and if additional 
treatment is given, at 21 day intervals thereafter; until injection 
number 9 (or last dose otherwise) and EOS. Afterwards data will be 
obtained on a monthly basis for a total of 6 months. 
Statistical analysis: 
No formal statistical analysis will be performed, however, statistical 
derivation of all data will be derived by dose cohort and displayed for 
inspection. 

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For the dose-escalation phase of the study, cohorts of 3 or 6 patients will be 
screened, registered and treated at each dose level. The actual sample size 
may vary depending on the incidence of DLT during Cycle 1 at a given dose 
level. Once the MTD/RP2D is determined, additional patients may be 
accrued to provide for 6 patients in the MTD cohort. Approximately, 
18 patients will be screened, registered and treated in the trial.  
The primary safety analysis will assess MTD and AEs, clinical laboratory 
tests, and tolerability, based on the combined evaluation of immunogenicity 
and incidence of DLTs in each patient. 
Study duration: 
The duration of the study for each patient will include an up to 8-week 
screening phase, 21-day study treatment cycles for 9 cycles and 6 months of 
follow up including monthly PSAs and an end of study visit (28 days post 
last dose of study treatment).  
Patients may continue to receive single repeated doses of SNS-301 at their 
original dose level (or at the MTD when it is determined) every 21 days for 
a total of 9 doses or until the observance of PSA doubling < 90 days or 
unacceptable toxicity (either for that patient or in their dose cohort). Patients 
who have received more than 9 injections due to the timing of the amendment 
limiting therapy to 6 months (9 doses), will be stopped at their last dose 
received and be followed for 6 months as with other patients. Patients with 
evidence of progression and declining HAAH immune parameters during 
this 6-month follow up period will have the option of immediately resuming 
therapy on study protocol. 

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1.1 TIME AND EVENTS SCHEDULES 
Table 1: Time and Events Schedule 
Assessment 
Screen 
(D-56+7e 
to D0) 
Cycle 1 
Assessments 
Cycle 2-3 
Additional 
Treatments 
Follow-
up/End of 
study 
 
D1 
D8 
± 2 
D15± 
2 
D22 
± 3 
D43 
± 3 
Every 21 ± 
3 day 
Every 28 ± 3 
days after 
final 
treatment for 
6 Months 
Signed Informed Consent 
X 
 
 
 
 
 
 
 
HAAH assessmenta 
X 
 
 
 
 
 
 
 
Demographics 
X 
 
 
 
 
 
 
 
Medical/Oncology 
History 
X 
 
 
 
 
 
 
 
Tumor Burden 
Evaluationd 
X 
 
 
 
 
 
 
 
Baseline Signs and 
Symptoms 
X 
 
 
 
 
 
 
 
Physical Examination 
X 
 
 
 
 
 
 
X 
Symptom-Directed 
Physical Examination 
 
X 
X 
X 
X 
X 
X 
 
Vital Signs 
X 
X 
X 
X 
X 
X 
X 
X 
ECOG Performance Score 
X 
X 
X 
X 
X 
X 
X 
X 
ECG 
X 
X 
 
 
X 
X 
X 
X 
PSA 
X 
X 
 
 
X 
X 
X 
X 
Hematologyb 
X 
X 
X 
X 
X 
X 
X 
 
Chemistryb 
X 
X 
X 
X 
X 
X 
X 
 
Coagulation, CH50b 
X 
X 
X 
X 
X 
X 
X 
 
Study Treatment 
administration 
 
X 
 
 
X 
X 
X 
 
Physician Administration 
Site Assessment 
 
X 
X 
 
X 
X 
X 
 
Immunologic Blood 
Collectionc 
 
X 
 
 
X 
X 
X 
X 
Cohort enrollment 
evaluation 
 
 
 
 
X 
 
 
 
Concomitant Medications 
Collection 
 
X 
X 
X 
X 
X 
X 
X 
Adverse Events 
Assessmentsf 
 
X 
X 
X 
X 
X 
X 
X 
Abbreviations: ECG: electrocardiogram; ECOG: Eastern Cooperative Oncology Group; PSA: prostate-specific antigen 
 
a  HAAH assessment: following informed consent, archived prostate tumor tissue and patient serum will be tested for the 
expression of HAAH. Only patients who test positive for HAAH expression in archived tumor tissue (if available) or 
fresh serum may be continued in the study.  HAAH assessments are not subject to the 56-day screening window and 
are valid for 6 months.  Patients who are negative for HAAH may be followed for 6 months and if PSA rises over that 
period time, they can enroll in the study provided that tissue or fresh serum is positive for HAAH 
b  Biochemical testing (chemistry, complete blood count, coagulation, and total complement CH50,) to be obtained within 
14 days prior to study drug administration if screening period is between 3 and 8 weeks. PSA levels are also to be 
evaluated at screening and within 14 days prior to study drug administration if screening period is between 3 and 8 
weeks. 
c  Immunologic blood collection: to be taken pre-dose on the day of study drug administration (Day 1) and every 21 days 
thereafter. Following the 9th dose (or last dose otherwise), PSA levels and other assessments will be followed on a 
monthly basis for 6 months. Patients with evidence of progression and declining HAAH immune parameters will have 
the option of resuming therapy on the study protocol. 

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d  Baseline radiological tumor burden evaluation consists of a baseline pelvic MRI or CT scan in addition to bone scan. 
These studies will need to be performed within 56 days (+ 7 days) prior to the start of the study. 
e  Patients that have a delay in screening beyond 56-days may be re-screened for randomization.  
f  Adverse events that occur post patient receiving study drug.  Should Adverse event occur prior to patient receiving 
study drug they will be captured as Medical History. 

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2.  TERMS, ACRONYMS, ABBREVIATIONS  
Term 
Definition 
7-ADD 
7-amino actinomycin D 
ADL 
Activities of daily living 
AE 
Adverse event 
ALT 
Alanine aminotransferase 
AP 
Alkaline phosphatase 
APC 
Antigen-presenting cells 
ASR 
Administration site reaction 
AST 
Aspartate aminotransferase 
°C 
Celsius 
CBC 
Complete blood count 
CFR 
Code of Federal Regulations 
CFSE 
Carboxyfluorescein succinimidyl ester 
CH-50 
Total complement activity 
CpG 
5’-c-phosphate-G-3’(a DNA sequence) 
CTL 
Cytotoxic CD8+ T-lymphocytes 
DLT 
Dose-limiting toxicity 
DNA 
Deoxyribonucleic acid 
ECG 
Electrocardiogram 
ECOG 
Eastern Cooperative Oncology Group  
eCRF 
Electronic case report form 
EDC 
Electronic data capture 
ELISA 
Enzyme-linked immunosorbent assay 
EOS 
End of study 
FDA 
Food and Drug Administration (U.S.) 
GMT 
Geometric mean titer 
gpD 
 Head DNA stabilization protein of Bacteriophase lambda 
HAAH 
Human aspartyl-asparaginyl-β-hydroxylase 
hMTS 
3M® hollow microstructured transdermal system 
ICF 
Informed consent form 
IgG 
Immunoglobulin G 
IND 
Investigational New Drug 
IRB 
Institutional review board 
irRC 
Immune-related response criteria 
kDa 
Kilodalton 
LVEF 
Left ventricular ejection fraction 

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Term 
Definition 
MACS 
Magnetic activated cell sorting 
MHC 
Major histocompatibility complex 
mL 
Milliliters 
M0 
Non-metastatic cancer 
M1 
Metastatic cancer 
MTD 
Maximum tolerable dose 
NCI-CTCAE 
V4.03 
National Cancer Institute Common Terminology Criteria for 
Adverse Events V 4.03 
PBMC 
Peripheral blood monocytes 
SNS-301 
HAAH bacteriophage lambda constructs: HAAH-1λ 
PSA 
Prostate-specific antigen 
RP 
Radical prostatectomy 
RP2D 
Recommended phase 2 dose 
SAE 
Serious adverse event 
WOCBP 
Women of child-bearing potential 

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3. INTRODUCTION 
3.1  Primary Disease and Study Treatment Information 
Human aspartyl-asparaginyl-β-hydroxylase (HAAH), also known as aspartate-β-hydroxylase, 
is an ~86 kDa type 2 transmembrane protein that belongs to the α-ketoglutarate-dependent 
dioxygenase family [1]. It is a highly conserved enzyme, which catalyzes the hydroxylation 
of aspartyl and asparaginyl residues in epidermal growth factor-like domains of proteins 
including Notch and homologs [2]. HAAH was initially identified in a novel screen to identify 
cell surface proteins up-regulated in liver cancer. It has subsequently been detected in a diverse 
array of solid and blood cancers, including: liver, bile duct, brain, breast, colon, prostate, 
ovary, pancreas, and lung cancers as well as leukemia. HAAH is not found in significant 
quantities in normal tissue or in proliferative disorders.   
Over-expression of HAAH has been demonstrated to be sufficient to induce cellular 
transformation, increase cellular proliferation and cellular motility and suppression of HAAH 
expression (small interfering ribonucleic acid) or neutralized activity (monoclonal antibodies) 
returns cancer cells to a normal phenotype. In cancer cells, it has been shown to be translocated 
to the cellular surface where it is not normally located. Because HAAH is an embryonic 
antigen, and as such presents self-antigen tolerance, it is relatively difficult to elicit a robust 
immune response against it. Thus, we posited that effective priming of antigen-presenting 
cells (APC) by HAAH antigen is an essential step to overcome tolerance. Indeed, in vitro 
activation of dendritic cells with HAAH, prior to re-administration to patients has shown 
promising results for liver cancer therapy [3]. Unfortunately, this process is cumbersome, 
expensive, time consuming and impractical for mass scale immunotherapy.   
Bacteriophage display is a simple, inexpensive and practical way of achieving favorable 
presentation of peptides to the immune system. The phage contains deoxyribonucleic acid 
(DNA) fragments that present the phage CpG motifs, which are known to stimulate the innate 
immune response and activate the major histocompatibility class (MHC) class II pathway in 
APC. Previous findings have revealed that recombinant bacteriophage can prime strong CD8+ 
T-lymphocyte (CTL) responses both in vitro and in vivo against epitopes displayed in multiple 
copies on their surface [4], activate T-helper cells [5] and elicit the production of specific 
antibodies [6, 7] all normally without adjuvant. Thus we have selected bacteriophage as a 
platform for eliciting anti-HAAH immune responses. Bacteriophage are ubiquitous and 
essentially innocuous to humans, however, as an added safety mechanism, they may be 
neutralized rendering them non-infective to host bacteria while retaining their 
immunostimulant properties. Once neutralized, the bacteriophage effectively becomes a 
nanoparticle, for enhanced delivery of protein fragments to APC.   
We have designed a bacteriophage lambda system to display HAAH peptides fused at the 
C-terminus of the head protein gpD of phage lambda. The phage carry 200-300 copies of the 
gpD protein on their head and thus display many copies of an approximately 25 kDa molecular 
weight fragment of HAAH on their surface. The drug substance is one of these HAAH 
bacteriophage lambda constructs: HAAH-1λ (SNS-301). 
 
 

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3.2  Previous Non-Clinical Experience 
Nonclinical studies have focused on the immunogenicity and efficacy of the HAAH 
Nanoparticle Vaccine in rodent models. Nonclinical toxicology studies have been completed 
and are described below. 
The nonclinical data generated to date include: 
• 
Demonstration of immunogenicity in mice and rats 
• 
Demonstration of dose response to both amount of vaccine and number of doses 
• 
Demonstration of both humoral and cellular immunity 
• 
Demonstration of enhanced immunogenicity for intradermal compared to 
intramuscular immunization 
• 
Efficacy data in three rodent tumor models, including solid tumors and metastases 
o Inhibition of solid tumor growth and metastases with the mouse hepatocellular 
carcinoma cell line, BNLT3 
o Inhibition of solid tumor growth, lung metastases and mortality with the mouse 
breast cancer cell line, 4T1 
o Inhibition of metastases with the rat prostate cancer cell line, MLLB-2 
The data listed above have been generated in three laboratories, which provide corroboration 
of the nonclinical observations in multiple environments and with multiple technical staff. It 
is important to note that there has been no local reactogenicity or adverse events (AEs) 
associated with the administration of multiple doses of the HAAH Nanoparticle Vaccine in 
mice and rats. These vaccines are immunogenic, show efficacy in three tumor model systems 
and are safe in the doses given to rodents. In total, the data strongly support the potential utility 
of the HAAH-1λ vaccine for the immunotherapy of cancer. 
It is anticipated that the HAAH Nanoparticle Vaccine will also prove to be safe in humans.  
Bacteriophages are ubiquitous in our environment. All humans are constantly exposed to large 
numbers of bacteriophage with no apparent harm. The relatively low dose and dose frequency 
of a vaccine as compared to other cancer drugs, both chemical and biological, also predict that 
these materials should be quite safe in human subjects.   
Panacea has conducted a repeated dose study in rats that assessed the toxicity of the SNS-301 
(previously named PAN-301-1) HAAH nanoparticle vaccine when administered 
intradermally at the same three dose levels (2 x 1010, 1 x 1011 and 3 x 1011 particles) and same 
dose schedule (3 doses given at 21 day intervals) as proposed for this human study, followed 
by 2 week and 4-week recovery periods.  These dose levels were chosen based on 
demonstrated immunogenicity and efficacy in the animal models described above. The 
conclusions of the study were that treatment with SNS-301 at doses up to 3 x 1011 particles 
had no effect on mortality, physical examinations, cage-side observations, dermal Draize 
observations, body weights or body weight changes, food consumption, body temperature, 
ophthalmologic observations, gross pathology, absolute and relative organ weights, 
hematology or clinical chemistry.  A slightly prolonged but non-adverse PT time in males 
given > 1 x 1011 particles and females given 3 x 1011 particles persisted through the first 
recovery period (2 weeks post-3rd injection).  The prolonged PT time resolved in males by the 
second recovery period (4 weeks post-3rd injection) but remained minimally prolonged in 
females given 3 x 1011 particles.  Test article-related microscopic findings were present in the 
injection site in animals given > 1 x 1011 particles and consisted of mild or moderate 
mononuclear or mixed inflammatory cell infiltrates in the dermis and/or subcutis.  These 
findings were considered non-adverse and resolved during recovery.  Additionally, the SNS-
301 vaccine demonstrated a significant antibody response that was dependent on both the dose 
level and number of doses administered.  

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These toxicology results demonstrate safety of the SNS-301 HAAH nanoparticle vaccine and 
support the planned multiple dose Phase 1 study of the HAAH Nanoparticle Vaccine in 
humans described in this protocol. 
3.3 Current Clinical Experience 
Review of Current Clinical Data with SNS-301 
Exposure 
A total of 12 patients have been treated with at least 5 doses of SNS-301.  All 12  of these 
patients are subjects in the current IND protocol..  Seven patients in the current study have 
already received 9 or more injections and will continue to receive treatment until the current 
amendment limiting dosing to 9 doses becomes effective. The listing of patient identifiers, 
primary cancer data, and exposure data are provided in Table 2. 
Table 2: Patients Treated with SNS-301 
Patient ID 
IND Study 
(Y/N) 
Primary Cancer 
Date of 
First Dose 
Dose 
Administered 
Number of 
Doses 
001-001 
Yes 
Prostate 
1/5/17 
2.0 x 1010 
1.0 x 1011 
3.0 x 1011 
11 
5 
6 
004-001 
Yes 
Prostate 
4/19/17 
2.0 x 1010 
1.0 x 1011 
3.0 x 1011 
7 
5 
7 
004-002 
Yes 
Prostate 
5/23/17 
2.0 x 1010 
1.0 x 1011 
3.0 x 1011 
5 
5 
7 
004-004 
Yes 
Prostate 
6/20/17 
1.0 x 1011 
3.0 x 1011 
9 
7 
004-003 
Yes 
Prostate 
7/18/17 
1.0 x 1011 
3.0 x 1011 
7 
2 
003-002 
Yes 
Prostate 
7/25/17 
1.0 x 1011 
3.0 x 1011 
6 
5 
001-003 
Yes 
Prostate 
8/21/17 
3.0 x 1011 
12 
003-006 
Yes 
Prostate 
11/13/17 
3.0 x 1011 
8 
004-006 
Yes 
Prostate 
11/20/17 
3.0 x 1011 
8 
004-007 
Yes 
Prostate 
11/29/17 
3.0 x 1011 
8 
001-004 
Yes 
Prostate 
12/20/17 
3.0 x 1011 
7 
003-007 
Yes 
Prostate 
1/29/18 
3.0 x 1011 
5 
 
 
 

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Local Tolerability 
Local tolerability of the drug administration is being evaluated after each dose at 1 hour, 7 
days and after each new injection.  The assessment of injection site reactions includes the 
evaluation of injection site pain, tenderness, erythema, erythema wheal measurement, 
swelling, and swelling wheal measurement. A total of 142 doses of SNS-301 have been 
administered to these 12 patients. In all cases, there have been no reports of a local injection 
site reaction immediately (1hr) following the first injection, at day 7 post injection, or 
following the second and subsequent injections.  
Biochemical Safety 
In the IND study patients, biochemistry, hematology, and PT/PTT/INR are measured pre-dose, 
at Day 8, Day 15, and Day 22 just prior to the second dose of study drug on an ongoing basis 
for each cycle of study drug. Patients treated compassionately have blood testing performed 
per the standard of investigator care. There have been no clinically significant changes in any 
analyte measured in the IND-treated patients over the course of the study. Further, there have 
been no reports of any laboratory abnormalities in patients receiving compassionate use SNS-
301. 
CH50 Complement 
Total complement (CH50) has been determined pre-treatment for each new dose, at Day 8, 
Day 15, and Day 22 prior to the next dose. There were no clinically relevant changes in CH50 
acutely (Day 8) or chronically every 22 days following multiple administrations of study drug.  
Clinical Safety 
There have been no serious adverse events reported in any of the 12 patients exposed to SNS-
301.  Three patients have experienced a total of 5 adverse events deemed to be possibly related 
to study drug as outlined in Table 3. All AEs are ≤ Grade 3.   
Table 3: Adverse Events 
Patient Number 
Adverse Event 
Date 
Dose 
001-001 
Migratory Arthralgia 
9/4/17 
1.0 x 1011 
001-001 
Migratory Arthralgia 
11/20/17 
1.0 x 1011 
001-001 
Migratory Arthralgia 
12/11/17 
1.0 x 1011 
001-004 
Erythema 
12/22/17 
3.0 x 1011 
003-002 
Shortness of breath 
12/06/17 
1.0 x 1011 
 
Dose Limiting Toxicities 
There have been no dose-limiting toxicities reported in the IND treated patients and no drug 
related events of any grade in the compassionate use treated patients. 
Progression 
To date, none of the SNS-301 treated patients have experienced disease progression. Table 4 
lists the patients and their current progression free interval. 
 
 

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Table 4: : Progression Free Intervals 
Patient ID 
IND 
Study 
(Y/N) 
Primary 
Cancer 
Date of First 
Dose 
Progressive 
Disease (Y/N) 
Current 
Progression Free 
Interval 
(months) 
001-001 
Yes 
Prostate 
1/5/17 
No 
> 15 
004-001 
Yes 
Prostate 
4/19/17 
No 
> 11 
004-002 
Yes 
Prostate 
5/23/17 
No 
> 11 
004-004 
Yes 
Prostate 
6/20/17 
No 
>10 
004-003 
Yes 
Prostate 
7/18/17 
No 
>9 
003-002 
Yes 
Prostate 
7/25/17 
No 
>9 
001-003 
Yes 
Prostate 
8/21/17 
No 
>8 
003-006 
Yes 
Prostate 
11/13/17 
No 
>5 
004-006 
Yes 
Prostate 
11/20/17 
No 
>5 
004-007 
Yes 
Prostate 
11/29/17 
No 
>5 
001-004 
Yes 
Prostate 
12/20/17 
No 
>4 
003-007 
Yes 
Prostate 
1/29/18 
No 
>3 
Conclusion 
While still early in the study, these data taken together suggest that SNS-301 is well tolerated, 
does not result in local injection site reactivity, and does not appear to result in dose limiting 
toxicities or metabolic complication.  
3.4 Study Rationale 
Oncology trials frequently employ dose-escalation using a 3+3 schema; it is considered 
standard practice for determining the MTD of a particular study treatment in humans. The 
starting dose for such studies is usually calculated from the results of toxicology studies, which 
are often not performed in humans [8]. In this study, the starting dose and the subsequent dose 
escalations were determined from the results of a repeated dose toxicology study conducted in 
rats that evaluated the same 3 intradermal doses and dose frequency for the SNS-301 as 
proposed here. Only minimal toxicologic effects were observed in the animals at the higher 
two dose levels and these were resolved through the 2- and 4-week recovery periods (see 
Section 3.2). 
The selection rationale for the specific dose levels proposed for this study is based on the in 
vivo results of this range of doses in mice and rats that have shown both immunogenicity and 
efficacy of the SNS-301 vaccine.  The vaccine has demonstrated immunogenicity in rats by 
IgG antibody response to recombinant HAAH and to the recombinant bacteriophage HAAH-
1λ drug substance at each dose level, 2 x 1010, 1 x 1011 and 3 x 1011 particles.  This antibody 
response is both dose level-dependent and dose number-dependent.  In mice, dose levels of 
approximately 2 x 1010 to 3 x 1011 particles have also demonstrated immunogenicity in a 
similar dose level- and dose number-response manner in multiple studies.  Furthermore, SNS-
301 vaccine doses up to 3 x 1011 particles have demonstrated inhibition of solid tumor growth 
and metastases in in vivo mouse tumor models with the mouse hepatocellular carcinoma cell 
line, BNLT3, and with the mouse breast cancer cell line, 4T1 and have demonstrated inhibition 
of metastases in a rat tumor model with the rat prostate cancer cell line, MLLB-2. 
The dose-escalation phase will be conducted in patients with biochemically relapsed prostate 
cancer because this is a cancer that generally takes a long time to develop. Further, archived 
patient tumor tissue will be tested for the HAAH epitope before enrollment into the study; 
patients who do not test positive for the HAAH epitope in archived tissue or fresh serum 

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sample will not be entered into the treatment phase as they are not deemed suitable candidates 
for the HAAH vaccine.  The 21-day treatment phase will allow the patient sufficient time to 
recover from any adverse effects of the vaccine before the next dose. It is anticipated that the 
SNS-301 will lead to the development of active anti-HAAH immunity with consistent 
polyclonal anti-HAAH antibody titers in addition to development of anti-HAAH T-cells. This 
is further supported by our current data from patients treated up to now. Based on this, a 
decision has been made to limit the total number of injections to 9, which accounts for 
6 months of treatment with an additional 6 months of follow up, with monthly measurement 
of PSA levels and anti-HAAH immunity parameters. Patients who, at the time of this 
amendment, have received more than 9 injections, will cease treatment at the time of their last 
injection when this amendment goes into effect and will also be followed for 6 months, as will 
patients whose disease progression leads to treatment stoppage before 1 year. Patients with 
evidence of progression and declining HAAH immune parameters have the option of resuming 
therapy on the study protocol in the 6 month follow up period. All patients are eligible for 
enrollment in the expanded access protocol after study closure.  
4. Study Objectives and Endpoints 
4.1 Study Objectives 
4.1.1 Primary   
• 
To determine the maximum tolerated dose (MTD) of SNS-301 based on the incidence 
of dose-limiting toxicities (DLT) and the maximum administered dose of SNS-301, 
when administered every 21 days in patients with biochemically relapsed prostate 
cancer 
4.1.2 Secondary 
• 
To assess the overall safety of SNS-301 
 
 

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4.2 Study Endpoints 
4.2.1 Primary 
• 
To determine the MTD 
• 
Determine the recommended Phase 2 dose (RP2D) if different than the MTD 
• 
Determine the DLTs associated with SNS-301 
4.2.2 Secondary 
• 
Incidence of administration site reactions 
• 
Biochemical safety and tolerability 
• 
Geometric mean titers of anti-HAAH antibodies by dose 
• 
Antigen-specific CTL responses by dose 
• 
Production of B cell and T cell response of interest  
4.2.3 Clinical secondary endpoints  
• 
Change in the prostate-specific antigen (PSA) velocity  
• 
Reduction in the PSA doubling time from pre-baseline  
4.2.4 Pharmacodynamic secondary endpoints 
• 
Duration of antigen-specific anti-HAAH antibody titers 
• 
Changes in the amplitude or duration of the production of anti-HAAH antibodies 
• 
Correlation of anti-HAAH titers and serum HAAH levels 
 
 

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5. INVESTIGATIONAL PLAN 
This is a Phase I, open-label, study of SNS-301, an HAAH-directed nanoparticle vaccine, 
given intradermally in cohorts of patients with biochemically relapse prostate cancer, using a 
fixed dose-escalation schema every 21 days to establish the MTD.  
5.1 Overall Study Design and Plan Description  
Figure 1: Dose-escalation study design (3+3 schema) 
 
 
 
Following informed consent and screening, archived prostate tumor tissue and patient serum 
will be tested for the expression of HAAH. Patients who test positive for HAAH expression 
in either archived tumor tissue or fresh serum may be continued in the study. Baseline 
biochemical testing (chemistry, complete blood count [CBC], coagulation panel, CH50, and 
PSA) will be obtained prior to study treatment administration.  
Treatment will consist of single repeated doses of SNS-301 administered every 21 days. A 
traditional 3+3 dose-escalation schema will be used to determine the MTD of SNS-301 for 
the first 2 doses and a modified dose-escalation schema with 6 patients per dose level for the 
remaining dose. Planned doses of SNS-301 are 2.0 x 1010, 1.0 x 1011 and 3.0 x 1011 particles 
per administration diluted to 1 mL and administered intradermally. Additional patients will be 
enrolled at the highest dose level until at least 6 patients can be evaluated even if no DLTs are 
observed at the dose. Planned treatment may continue for two additional doses of SNS-301 
administered every 21 days.  Serum and whole blood samples will be obtained on the day of 
study treatment administration (Day 1) and 21 days thereafter. In patients who continue to 
receive study treatment, biochemical and immunologic testing will continue every 21 days. 
The MTD will be determined over the first 21-day interval following a single dose of SNS-
301 in 3 consecutive dose cohorts. The MTD will be considered the dose level lower than that 

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dose which produces ≥ 2 DLTs in 3 or 6 patients. A DLT will be considered a protocol-
specified drug-related grade 3-4 (National Cancer Institute Common Terminology Criteria for 
Adverse Events [NCI-CTCAE] V 4.03) adverse experience) (Section 5.4.5.1). The RP2D will 
be the highest dose administered if no MTD is observed.  
Dose cohorts will be enrolled sequentially.  
An evaluation period of at least 21-days for the first patient (sentinel patient) in a new cohort 
is required to evaluate tolerability before adding additional patients to the cohort. If 
safety/tolerability is adequate, then the remaining patients will be dosed in the cohort.  A 
second evaluation will occur for the last patient of each cohort of at least 21-days to evaluate 
safety/tolerability before dose escalation to the next cohort will occur.  Enrollment will be 
held if an administration site reaction (ASR) of grade 3 or greater (NCI-CTCAE V4.03) is 
observed until the event resolves.  In the event enrollment is held for an ASR, the Sponsor, 
Medical Monitor and PI will evaluate the outcome of the ASR and must agree to continued 
enrollment.  
Dose-escalation will proceed once all patients in a cohort (unless the MTD is observed) have 
completed a 21-day safety evaluation following the first dose of study treatment in the cohort.  
Planned treatment may continue for an additional 2 extra doses of SNS-301 administered 
every 21 days.  Additional patients will be enrolled at the highest dose level until at least 6 
patients can be evaluated even if no DLTs are observed at the dose  In patients who tolerate 
SNS-301, additional treatment may be continued with single doses of SNS-301 at their current 
dose level, to maintain geometric mean titer (GMT) of HAAH antibodies to no less than 4 
times the baseline value for at least six months (9 injections). Treatment will be terminated 
with the 9th injection or will otherwise be terminated at any time upon the observance of PSA 
doubling < 90 days or occurrence of unacceptable toxicity as determined by the Investigator 
(either for that patient or in their dose cohort). After termination, patients will be followed for 
an additional 6 months with monthly PSA levels and imaging studies as needed. 
Once the MTD/RP2D is determined, patients receiving ongoing treatment may be escalated 
to that dose for subsequent treatments and receive a maximum of 9 injections. Patients who 
have received more than 9 injections due to the timing of the amendment limiting therapy to 
6 months (9 doses), will be stopped at their last dose received and be followed for 6 months 
as with other patients. These subjects will continue to be followed for safety and biochemical 
PSA monitoring on a monthly basis for 6 months and are eligible to resume SNS-301 in case 
of increases in PSA doubling to < 90 days or other evidence of disease progression and decline 
in immunological parameters. 
Pharmacodynamic:  
Exploratory pharmacodynamic (PD) analysis will be performed using dose, vaccine-specific 
antibody response (geometric mean titer), antigen-specific T and B cell indices, and the 
relative expression of HAAH in each patient’s tumor. The PD will be balanced and optimized 
to the degree of antigen-specific immune response and minimized for the production of 
regulatory immune processes. 
Other Safety:  
Safety endpoints will be evaluated by the incidence and severity of administration site 
reactions, changes in biochemical safety measures, general incidence and types of AEs, 
serious adverse events (SAEs), and other overt toxicities. 

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5.2 Selection of Study Population 
5.2.1 Inclusion Criteria 
1. Signed and dated written Ethics Committee approved informed consent 
2. Men aged 21 to 85 years with a histologic diagnosis of prostate cancer with a 
biochemical relapse following definitive local therapy (RP or radiation therapy) 
3. Patients are not eligible or are unwilling to receive additional definitive therapy 
following relapse (either RP or radiation therapy)  
4. No prior cytotoxic chemotherapy for the current cancer 
5. Normal electrocardiogram (ECG) or ECG with no clinically significant findings as 
determined by the Principal Investigator 
6. Presence of biochemically relapsed prostate cancer defined as either: 1) PSA > 2 
ng/mL 1 year following initial definitive treatment for prostate cancer: or, 2) PSA 
doubling time (greater than 0.2 ng/mL) < 12 months; or, 3) PSA velocity > 2 
ng/mL/year at any time following radical prostatectomy or radiation therapy.  
7. Positive expression of HAAH in either archived tumor tissue (if available) or fresh 
serum 
8. No clinical or radiologic evidence of distant metastatic disease as measured by pelvic 
MRI or CT scan in addition to bone scan. These studies will need to be performed 
within 56 (+ 7 days) days prior to the start of the study. 
9. No history of immunosuppressive disease 
10. No evidence of active autoimmune disease. Active autoimmune disease is defined as 
any disease process that has specifically needed administration of immune 
suppressive and or cytoreductive therapy currently or within the last 1 year. 
11. Able and willing to comply with all study procedures 
5.2.2 Exclusion Criteria 
1. PSA doubling time of < 3 months 
2. Participation in a clinical trial within 30 days prior to enrollment 
3. Prior major surgery or radiation therapy within 4 weeks of enrollment 
4. Any illness or condition that in the opinion of the Investigator may affect the safety 
of the patient or the evaluation of any study endpoint 
5. Screening blood counts of the following:  
Hematopoietic:  
Absolute neutrophil count < 1500/μL,  
Platelets < 100,000/μL,  
Hemoglobin < 9 g/dL; 
Liver/Metabolic:  
Alanine aminotransferase (ALT) and aspartate transaminase (AST) > 2.5 × ULN 
range,  
Total bilirubin > 2 × ULN,  
Albumin < 2.8 g/dL; 
Renal:  
Creatinine clearance < 50 mL/min as predicted by the Cockcroft-Gault formula 
6. Subjects whose partners are WOCBP must use an adequate method of birth control 
while on study drug and at least for 3 weeks after discontinuation of study drug 

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7. Current or anticipated concomitant immunosuppressive therapy (excluding non-
systemic inhaled, topical skin and/or eye drop-containing corticosteroids) 
8. Any concurrent condition requiring the continued use of systemic steroids (see 
above) or the use of immunosuppressive agents including methotrexate. All other 
systemic corticosteroids must be discontinued at least 4 weeks prior to first study 
treatment 
9. Receipt of any blood product within 1 month of enrollment 
10. Receipt of any vaccine within 4 weeks of enrollment 
11. Active drug or alcohol use or dependence that, in the opinion of the Investigator, 
would interfere with adherence to study requirements 
12. Been imprisoned or compulsorily detained (involuntarily incarcerated) for treatment 
of either a psychiatric or physical (i.e. infectious disease) illness 
13. Patients who have a history of coagulopathies, thrombosis or who are receiving active 
anticoagulation for any condition, such as but not limited to, artificial heart valves, atrial 
fibrillation, etc.  
14. Any other conditions judged by the Investigator that would limit the evaluation of a 
subject 
5.2.3 Removal of Patients from Treatment or Assessment 
The patients may withdraw from treatment with study product if they decide to do so, at any 
time and irrespective of the reason, or this may be the Investigator’s decision to protect the 
safety of the patient. All efforts should be made to document the reason for discontinuation 
and this should be documented in the electronic case report form (eCRF). 
Other criteria for possible discontinuation are: 
• 
PSADT < 90 days 
• 
Unacceptable toxicity as judged by the Principal Investigator 
Adverse events which are dose-limiting toxicities  
Patient is lost to follow-up 
Patients will be followed up according to the study procedures as specified in this protocol up 
to the scheduled date of study completion, or up to recovery or stabilization of a followed-up 
AE, or the initiation of post study treatment, whichever comes last. 
If possible, and after the permanent discontinuation of treatment, the patients will be assessed 
using the procedure normally planned for the ‘end of study’. 
The patients may withdraw from the study follow-up schedule, before study completion if 
they decide to do so, at any time and irrespective of the reason, or this may be the 
Investigator’s decision: 
Patients who are lost to follow-up: 
The Investigator should make every effort to re-contact the patient, to identify the reason 
why he/she failed to attend the visit, and to determine his/her health status, including 
at least his/her vital status. Attempts to contact such patients must be documented in 
the patient’s records (e.g. times and dates of attempted telephone contact, receipt for 
sending a registered letter).  
Patients who did not complete the study and for whom no endpoint data are available will 
be considered as lost to follow-up. 

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The statistical analysis plan will specify how these patients lost to follow-up for their 
primary endpoints will be considered. 
5.2.4 Enrollment Holds 
Enrollment will be held if the subject experiences a grade 3 or greater ASR as determined by 
the Investigator. The subject must be withdrawn from the study if they experience a grade 3 
ASR. Enrollment can be re-started after agreement between the Principal Investigator, 
Medical Monitor, and the Sponsor. 
Study enrollment will be halted in the event of a death of a subject while on the study or within 
a 30-day period follow study drug exposure regardless of drug relationship. In the event the 
enrollment is halted, a clinical review of the subject case will be made by the Principal 
Investigator, Medical Monitor, and the Sponsor to assess the safety of the medicinal product. 
If the review concludes there is no association of the death with the study drug, restarting 
enrollment may proceed. 
5.3 Study Treatment 
5.3.1 Treatments Administered 
Subjects will be administered intradermally the SNS-301 doses of 2.0 x 1010and 1.0 x 1011 
particles per administration according to the 3+3 dose-escalation schema described herein and 
for the 3.0 x 1011 particles per administration dose additional patients will be enrolled until at 
least 6 patients can be evaluated even if no DLTs are observed at the dose. Planned treatment 
may continue of additional doses of SNS-301 administered every 21 days.  
5.3.2 Identity of the Study Treatment 
5.3.2.1 Study Treatment Details 
The HAAH Nanoparticle Vaccine drug substance is a recombinant bacteriophage lambda 
construct that is engineered to display a fusion protein of phage gpD and a portion of the 
HAAH protein sequence. The HAAH-1λ (SNS-301) construct contains 199 amino acids from 
the N-terminal region (amino acids 113 – 311) of the molecule. 
The drug substance is characterized by testing that includes appearance, pH, and identity by 
dot blot using HAAH-specific monoclonal antibody, impurities (bioburden, endotoxin, host 
cell protein), determination of size distribution by particle analysis, quantitation by particle 
analysis, protein determination and potency by antigen enzyme-linked immunosorbent assay 
(ELISA). 
5.3.2.2 Study Treatment Administration 
The vaccine will be delivered intra-dermally by a single-use 3M® hollow microstructured 
transdermal system (hMTS) device. 
5.3.2.3 Handling and Storage of Study Treatment 
5.3.2.3.1 Packaging and labeling 
The study treatment, SNS-301, will be packaged by the Sponsor, and supplied in an open-label 
basis. 
The supplies will be labeled as follows: 
• 
Sponsor’s name and address 

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• 
Study number 
• 
Content of the vial 
• 
Dosing instructions 
• 
Batch Number 
• 
"Caution: New Drug--Limited by Federal (or United States) law to investigational 
use." 
5.3.2.3.2 Storage 
The study drug product is stored at 2 – 8 °C. Temperature excursions to <25°C for less than 
24 hours are acceptable. 
5.3.2.4 Handling/Responsibilities 
The study Treatment administrator must store and administer the study treatment according to 
the instructions provided by the Sponsor. 
All study treatments shall be dispensed in accordance with the Investigator's prescription and 
it is the Investigator's responsibility to ensure that an accurate record of study treatment issued 
and returned is maintained. 
Any quality issue noticed with the receipt or use of a study treatment (deficiency in condition, 
appearance, pertaining documentation, labeling, expiry date, etc.) should be promptly notified 
to the Sponsor, who will initiate a complaint procedure. 
Under no circumstances will the Investigator supply study treatment to a third party, allow the 
study treatment to be used other than as directed by this Clinical Trial Protocol, or dispose of 
study treatment in any other manner. 
5.3.2.5 Study Investigational Treatment Management and Disposal 
All unused study treatments should be discarded at the investigational site and a destruction 
certificate obtained. The study treatment Administrator will submit the copy of Product 
Accountability Log to the Sponsor. 
A potential defect in the quality of the study treatment may be subject to initiation by the 
Sponsor of a recall procedure. In this case, the Investigator will be responsible for promptly 
addressing any request made by the Sponsor, in order to recall study treatment and eliminate 
potential hazards. 
5.3.3 Method of Assigning Patients to Study Groups 
This is an open-label dose-escalation study; no randomization will occur. 
All patients who sign the informed consent form (ICF) will be assigned a patient study 
number. Patient eligibility must be verified by the Investigator. If a patient fails to meet an 
eligibility criterion during the screening period, then the Investigator will complete a screening 
failure form in the e-CRF. 
The study treatment will be administered only to patients included in this study following the 
procedures set out in this clinical study protocol. Details of the exact time of administration 
of medication (day/month/year, hour:minute) and the labeling on SNS-301 vials will also be 
documented in the e-CRF.  
Patient withdrawn from the study retain the same patient number. New patients must always 
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5.3.4 Selection of Doses for the Study 
This is an open-label study. Sequential cohorts will be enrolled in the order they present. In 
the dose-escalation cohorts, 3 or 6 patients will be treated with successively higher doses of 
SNS-301: 2.0 x 1010, 1.0 x 1011 and 3.0 x 1011 particles every 21 days.  
5.3.5 Selection and Timing of Dose for Each Patient 
The MTD will be determined over the first 21-day interval following a single dose of SNS-
301 in 3 dose cohorts. The MTD will be considered the dose level lower than that dose which 
produces ≥ 2 DLT. 
Dose-escalation will proceed when once all patients in a cohort (unless the MTD is observed) 
have completed a 21-day safety evaluation following the first dose of study treatment in the 
cohort. Multiple patients can be in screening phase simultaneously, but the first eligible patient 
able to be treated will be assigned the next treatment slot that is available for study. 
More specifically, the first patient of each dose level will be enrolled and assessed for DLTs 
during cycle 1. Subsequent patients in a cohort can be enrolled after a 21-day review for 
tolerability by the Medical Monitor, Sponsor and Investigator(s) has been completed in the 
first patient.  
After evaluation of the safety data of 3 patients in cycle 1 of the 2.0 x 1010 particles per 
administration dose, if none of the first 3 patients experiences a DLT, then dose-escalation to 
the next level (1.0 x 1011 particles per administration) can occur. When one patient shows a 
DLT, an additional 3 patients will be enrolled at the same dose level. If no more than 1 out of 
6 patients experiences a DLT, patient enrollment to the next dose level can start.  
Patients who withdraw from the study during cycle 1 (Day 1 – Day 22 pre-dose) for reasons 
other than safety or toxicity will be replaced.  
Subsequent dose-escalation will be conducted in the same manner. 
If the MTD is not achieved at the dose level of 3.0 x 1011 particles per administration, further 
dose-escalation will not be conducted. Additional patients will be enrolled at the highest dose 
level until at least 6 patients can be evaluated even if no DLTs are observed at the dose. 
Although the dose-escalation process is guided by the safety evaluation during cycle 1, the 
global safety profile of SNS-301 at each dose level will be considered and discussed with the 
Investigator before increasing doses. 
Planned treatment may continue for additional doses of SNS-301, administered every 21 days.   
In patients who tolerate SNS-301, additional treatment may be continued with single doses of 
SNS-301 at their current dose level every 21 days, to maintain geometric mean titer (GMT) 
of HAAH antibodies to no less than 4 times the baseline value for at least six months (9 
injections). 
Treatment will be terminated with the 9th injection or will otherwise be terminated at any time 
upon the observance of PSA doubling < 90 days or occurrence of unacceptable toxicity. After 
termination, patients will be followed for an additional 6 months with monthly PSA levels and 
imaging studies as needed. 
Once the MTD/RP2D is determined, patients receiving ongoing treatment may be escalated 
to that dose for subsequent treatments and receive a maximum of 9 injections. Patients who 
have received more than 9 injections due to the timing of the amendment limiting therapy to 
6 months (9 doses), will be stopped at their last dose received and be followed for 6 months 
as with other patients. These subjects will continue to be followed for safety and biochemical 
PSA monitoring on a monthly basis for 6 months and are eligible to resume SNS-301 in case 

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of increases in PSA doubling to < 90 days or other evidence of disease progression and decline 
in immunological parameters. 
5.3.5.1 Dose-limiting toxicities 
Any of the following, if judged to be associated with SNS-301 (i.e., possibly-, probably-, or 
definitely related to), will be considered a DLT which are based on the NCI-CTCAE V4.03 
criteria: 
1) Grade 4 non-hematological toxicities (excluding alopecia) of any duration 
2) Grade 3 non-hematologic (non-laboratory) toxicity lasting > 3 days despite optimal 
supportive care  
3) Any Grade 3 or Grade 4 non-hematologic laboratory value if: a). Medical 
intervention is required to treat the subject; b), the abnormality leads to 
hospitalization; c). The abnormality persists for >1 week.  
4) Grade 4 hematologic toxicity, other than those specified in criteria 5 and 6 below, 
lasting > 7 days 
5) Grade 3 or Grade 4 febrile neutropenia of any duration 
6) Grade 3 thrombocytopenia in combination with a grade 3 or greater blood and 
lymphatic system disorder 
7) Grade 3 AST or ALT that is associated with a grade 2 rise in bilirubin 
5.3.5.2 Dose delay or reduction 
In case of non-DLT AE (grade 2 NCI-CTCAE V4.03 drug related AE), the dosing interval of 
3 weeks can be extended to up 42 days to allow the recovery from a related toxicity and the 
patient will resume at the same dose. If the patient experiences the same toxicity requiring a 
dose-delay at the subsequent cycle, the patient should be discontinued. 
No sentinel safety assessment will be made; however, enrollment will be controlled so that a 
21-day observation period is completed on the first subject in each cohort before any further 
enrollment is performed. Additionally, enrollment will be held if an ASR of grade 3 or greater 
is observed until the event resolves. In the event enrollment is held for an ASR, the Sponsor 
and PI will evaluate the outcome of the ASR and must agree to continued enrollment. 
5.4 Blinding 
This was an open-label study, so there will be no blinding of study personnel. 
5.4.1 Prior and Concomitant Treatment 
All treatments being taken by the patients at entry to the study or at any time during the study 
in addition to the study treatment are regarded as concomitant treatments and must be 
documented in the appropriate screen of the e-CRF. 
5.4.1.1 Allowed concomitant treatments 
The following concomitant treatments are permitted during this study: 
• 
Supportive treatment will be given as medically indicated. 
• 
Prophylactic antiemetic premedication including corticosteroids and 
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5.4.1.2 Prohibited Medications or Treatments During Study 
Medications such as those listed below are not permitted in the course of the trial: 
• 
Concurrent treatment with other investigational drugs 
• 
Concurrent treatment with any other anticancer therapy including radiotherapy 
5.4.2 Study Treatment Accountability and Compliance Procedures 
Administration of the study treatment will be supervised by the Investigator or 
sub-Investigator. The study treatment should not be destroyed until the site is contacted by the 
Sponsor to provide disposition details. The person responsible for drug dispensing is required 
to maintain adequate records of the study treatment. These records (e.g., product 
accountability log) include the date the study treatment is received from the Sponsor and 
administered to the patient. 
The person responsible for study treatment administration to the patient will record precisely 
the date and the time of the study treatment administration.  
5.5 Safety and Efficacy Variables and Study Assessments  
Flow charts for the study assessments are provided in Table 1. 
5.5.1 Pre-study Assessments 
5.5.1.1 HAAH expression of archived tissue 
After patient consent is given, archived tumor tissue (if available) and serum will be tested for 
the expression of HAAH. Patients who test positive may be enrolled into the study. 
5.5.1.2 HAAH expression in serum  
After patient consent is given, patient serum will be tested for the expression of HAAH 
(Section 7.5.3.2). Patients who test positive will be enrolled into the study. 
5.5.2 Study visits and assessments 
The following evaluations will be performed. All procedure dates defined are based on the 
duration (days) from the initial dose of study medication. 
5.5.2.1 Screening period (Day -56 (+ 7 days) to Day 0) 
Following patient informed consent, archived prostate tumor tissue and patient serum will be 
tested for the expression of HAAH. Only patients who test positive for HAAH expression in 
archived tumor tissue (if available) or fresh serum may be continued in the study.  If tumor 
tissue or fresh serum is initially negative for HAAH, the patient can be re-screened for the 
study if PSA level have increased over the next 6 months, patient is willing to participate on 
study in the future, and HAAH expression is now positive in serum or tumor tissue (on retest).  
If archived tumor tissue is negative on initial testing, the same tumor tissue will not be re-
tested. 
Assessments at Screening: 
• 
Informed consent administered 
• 
HAAH expression in archived tumor tissue (if available) and/or fresh serum 
• 
Medical/oncology history, demographics 
• 
Baseline signs and symptoms  
• 
Physical examination, vital signs, ECG 

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• 
Eastern Cooperative Oncology Group (ECOG) performance score 
• 
Prostate-specific antigen (PSA) assessment: if the screening period is between 3 and 
8 weeks prior to first dose, the PSA must be re-tested within 14 days prior to first dose 
• 
Clinical laboratory tests, chemistry, hematology, coagulation, CH50 if the screening 
period is between 3 and 8 weeks prior to first dose, the labs noted must be re-tested 
within 14 days prior to first dose 
• 
Pelvic MRI or CT scan in addition to bone scan. 
5.5.2.2 Dose-escalation Treatment: Day 1 
• 
Immunologic blood collection – pre-dose on day of drug administration (eg Day 1) 
and 21 days thereafter. 
• 
Medical/oncology history review 
• 
Symptom-directed physical examination 
• 
Prostate-specific antigen (PSA) assessment  
• 
Vital signs, ECG  
• 
ECOG score 
• 
Baseline biochemical testing (chemistry, CBC, coagulation, CH50,) prior to study 
drug administration 
• 
Study treatment administration 
• 
Physician administration site assessment (post administration) 
• 
Adverse events and concomitant medications 
5.5.2.3 Dose-escalation Treatment: Day 8 ± 2 days 
• 
Symptom-directed physical examination 
• 
Vital signs 
• 
ECOG score 
• 
Biochemical testing: chemistry, hematology, coagulation, CH50 
• 
Physician administration site assessment 
• 
Adverse events, concomitant medications 
5.5.2.4 Dose-escalation Treatment: Day 15 ± 2 days 
• 
Symptom-directed physical examination 
• 
Vital signs 
• 
ECOG score 
• 
Clinical laboratory tests, chemistry, hematology, coagulation, CH50 
• 
Adverse events, concomitant medications 
5.5.2.5 Study Visits: Day 22, Day 43 ± 3 days 
• 
Immunologic blood collection – pre-dose on day of drug administration on Day 22, 
43, and every 21 days thereafter if continuing treatment 
• 
Symptom-directed physical examination 
• 
Vital signs and ECG  
• 
Eastern Cooperative Oncology Group (ECOG) performance score 
• 
Prostate-specific antigen (PSA) assessment  
• 
Biochemical testing: chemistry, hematology, coagulation, CH50 
• 
Evaluation of subject to allow continued dose escalation 
• 
Study treatment administration 
• 
Physician administration site assessment (post-administration) 
• 
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5.5.2.6 Additional treatment: Every additional 21 days ± 3 days if indicated 
A maximum of 9 drug administrations will be administered on this study for all patients, 
except in the case of progression on study and or in the case of patients who had been on study 
for more than 6 months at the time of this amendment. Patients with evidence of progression 
and declining HAAH immune parameters within 6 months of stopping therapy have the option 
of resuming therapy on the study protocol. 
• 
Immunologic blood collection – pre-dose on day of drug administration every 21 days 
thereafter if continuing treatment.  
• 
Symptom-directed physical examination 
• 
Vital signs and ECG  
• 
Eastern Cooperative Oncology Group (ECOG) performance score 
• 
Prostate-specific antigen (PSA) assessment  
• 
Biochemical testing: chemistry, hematology, coagulation, CH50 
• 
Study treatment administration  
• 
Physician administration site assessment (post-administration) 
• 
Adverse events and concomitant medications 
5.5.2.7 Follow up and End of Study (EOS): 28 days ± 3 days after last treatment for a total 
of 6 months 
• 
Complete physical examination 
• 
Vital signs 
• 
Eastern Cooperative Oncology Group (ECOG) performance score 
• 
ECG 
• 
Prostate-specific antigen (PSA) assessment  
• 
Clinical laboratory tests, chemistry, hematology, coagulation, CH50 (only on first 
follow up) 
• 
Immunologic blood collection  
• 
Adverse events and concomitant medications 
5.5.3 Safety Measurements 
5.5.3.1 Clinical Laboratory Assessments 
Hematological toxicities will be assessed in term of hemoglobin value, white blood cell, 
neutrophil, platelet and, lymphocyte count according to NCI-CTCAE V4.03 AE grading. 
Laboratory abnormalities (grade 1 and greater that are listed in the NCI-CTCAE V4.03) 
should be recorded on the AE page regardless of their causality. Test analytes are provided in 
the table below. 
 
 
 
 
 
 
 
 

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Hematology 
Serum chemistry 
Full and differential blood count 
Hematocrit (Hct) 
Hemoglobin (Hgb) 
Platelet count 
Red blood cell (RBC) count  
White blood cell (WBC) count with differential 
 
Albumin 
Alanine aminotransferase (ALT) 
Aspartate aminotransferase (AST) 
Alkaline phosphatase (ALP) 
Blood Urea Nitrogen (BUN) or Urea 
Carbon dioxide (CO2) 
Creatinine 
Electrolytes (Na, K, Cl, Ca, P) 
Glucose (either fasting or non-fasting) 
Lactate dehydrogenase (LDH)  
Total bilirubin 
Direct bilirubin 
Total cholesterol 
Triglycerides 
 
Coagulation, CH50 
PSA 
Prothrombin time (PT)/INR  
Activated partial thromboplastin time 
(PTT) 
PSA 
5.5.3.2 Immunological blood collection 
Antigen-specific anti-HAAH antibody titers  
Anti-HAAH antibody titers from serum samples are determined by ELISA.  Patient sera are 
serially diluted and incubated in microplate wells coated with recombinant HAAH antigen.  
The plates are then incubated with anti-human immunoglobin G (IgG)-peroxidase conjugate, 
followed by color development to detect the amount of patient IgG bound to the HAAH 
antigen.  The data are expressed as the reciprocal of the end-point titer. 
Antigen-specific CTL responses  
Cytotoxic T-cells (CTLs) and APC will be isolated from patient peripheral blood monocytes 
(PBMCs) by magnetic activated cell sorting (MACS) on the basis of specific cell surface 
markers. APCs will be loaded with antigen (HAAH) for 3 hours and labeled with a fluorescent 
dye, carboxyfluorescein succinimidyl ester (CFSE), and incubated with CTLs at varying 
effector to target cell ratios. Cell-mediated cytotoxicity is determined by antigen-specific 
release of dye. 
Cytotoxic T-Lymphocyte Killing Assay 
Quantitation of specific cell lysis by patient-derived CD8+ T-cells will be determined using a 
flow cytometric assay employing two fluorochromes, 5- (and 6-) carboxyfluorescein diacetate 
succinimydyl ester (CFSE) and 7-amino actinomycin D (7-AAD). CFSE is pre-loaded into 
target cells where upon internalization it is covalently linked to intracellular amine groups and 
thus does not leach from cells into the media nor is it transferred to adjacent cells. As such, 
CFSE can be used as a marker to differentiate between effector and target cells in the final 
assay. 7-AAD is a membrane impermeable dye that when added subsequent to the period of 
cell lysis can only be incorporated only into dead cells (whose membranes have been 
compromised) and thus can be used to differentiate between live and dead cells.  

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Target Cells: Patient derived antigen presenting cells (APCs) will be isolated from peripheral 
blood mononuclear cells (PBMCs) using magnetic assisted cell separation (MACS) 
technology (Miltenyi Biotec). APCs may be loaded with antigen (HAAH) for 12-16 hrs. prior 
to use in the CTL assay. Immediately prior to assay, target cells will be loaded with CFSE.  
Effector Cells: CD8+ T-cells will be isolated from peripheral blood mononuclear cells 
(PBMCs) using magnetic assisted cell separation (MACS) technology (Miltenyi Biotec). 
Lysis: Effector and target cells will be co-incubated at varying effector to target cell ratios at 
37⁰C for 4 hours. Target cells are held constant at ~25,000 cells per well of a 96 well plate 
while effector cells will be varied from a ratio of 1:1 with target cells up to 25:1. After 
incubation, cells are labeled with 7-AAD to differentiate between live and dead cells. Cells 
are subsequently analyzed by flow cytometry four staining populations are counted: those that 
stain with both CFSE and 7-AAD, those that stain with CFSE but not 7-AAD, those that stain 
with 7-AAD but not CFSE and those that do not stain with either fluorophore. Percent specific 
lysis is determined by taking the ratio CFSE/7-AAD labeled cells to total CFSE labeled cells. 
The ratio of non-CFSE labeled cells vs. CFSE labeled cells is an indicator of the true effector 
to target cell ratio. 
Measurement of B cell and T cell response  
B cells will be isolated from patient PBMCs by magnetic activated cell sorting (MACS) on 
the basis of specific cell surface markers. After several days of growth in culture, medium will 
be tested for antigen-specific anti-HAAH antibody titers as above. 
CD4+ T-cells responses will be determined by isolating CD4+ T-cells and APC from patient 
PBMCs by magnetic activated cell sorting (MACS) on the basis of specific cell surface 
markers. APCs will be loaded with or without antigen (HAAH) for 3 hours and coincubated 
with CD4+ T-cells overnight. Antigen-specific T-cell activation will be determined by flow 
cytometric measurement of CD154 and interferon γ. 
Measurement of CD4, CD8, CD19 cell populations 
CD4+, CD8+ and CD19+ cell populations as a percentage of total PBMCs will be determined 
by flow cytometry. 
5.5.3.3 Administration site reaction 
The area around the administration site will be assessed by the physician for adverse reactions 
at least 30 minutes post study drug administration. The Investigator will grade any ASRs 
according to the NCI-CTCAE V4.03 (excluding the actual expected micro-injection 
punctures).  
Patients will be required to report any change in the administration site and return to the clinic 
for evaluation by the Investigator. 
5.5.3.4 ECOG performance score 
The health, activity and well-being of the patient was measured by the ECOG performance 
status and was assessed on a scale of 0 to 5 with 0 being fully active and 5 being dead. Full 
details are described in Appendix A. 
5.5.3.5 Adverse Events (AE) 
Adverse event means any untoward medical occurrence associated with the use of a drug in 
humans, whether or not considered drug related and occurs after the patient is given the first 
dose of study drug.  Any AE that occurs prior to the first dose is part of the medical history.  

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At least 30 minutes post dose, the Investigator should evaluate the site of drug administration 
and query the patient in a general manner regarding the presence of any untoward effects. 
Laboratory abnormalities (grade 1 and greater that are listed in the NCI-CTCAE V4.03) 
should be recorded on the AE page regardless of their causality. Worsening of a pre-existing 
condition is also considered an AE as is the discovery of an abnormal finding during physical 
exam that was not included in the medical history. 
Patients will be encouraged to spontaneously report any AE.  Study personnel will ask 
open-ended questions to obtain information about AEs at every visit.  Date and time of onset 
and resolution (if applicable) of the AE will be documented. 
Causality 
Events will be considered treatment related if classified by the Investigator as possible, 
probable, or definitely associated with the use of the drug.  Association of events to the study 
treatment will be made using the following definitions: 
 
Term 
Definition 
Definitely Not 
The event is definitely not associated with study treatment. 
Probably Not 
The temporal association, patient history, or clinical condition is such that 
the study treatment is not likely to have had an association with the 
observed event. 
Possible 
The event: a) follows a reasonable temporal association with the study 
treatment administration, but b) could have been produced by the patient’s 
clinical condition or other therapy. 
Probable 
The event: a) follows a reasonable temporal association with the study 
treatment, b) abates upon discontinuation of study treatment, and c) cannot 
be reasonably explained by the patient’s clinical condition or other therapy. 
Definite 
The event: a) follows a reasonable temporal association with the study 
treatment, b) abates upon discontinuation of study treatment, c) cannot be 
reasonably explained by the patient’s clinical condition or other therapy, 
and d) reappears on re-exposure to the study treatment. 
 
Severity 
Signs and symptoms will be graded by the Investigator using the NCI-CTCAE V4.03 graded 
1-5. Grade refers to the severity of the AE. For events not described in the NCI CTCAE, the 
Investigator will assign grades as 1= mild, 2=moderate, 3=severe, 4=life-threatening, and 
5=fatal based on this general guideline: 
Grade 1: Mild; asymptomatic or mild 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 of hospitalization indicated; disabling; limiting self-care ADL**.  
Grade 4: Life-threatening consequences; urgent intervention indicated.  

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Grade 5: Death related to AE.  (Grade 5 (Death) may not appropriate for some AEs and 
therefore may not an option.) 
Activities of Daily Living (ADL)  
*Instrumental ADL refer to preparing meals, shopping for groceries or clothes, using the 
telephone, managing money, etc.  
**Self-care ADL refer to bathing, dressing and undressing, feeding self, using the toilet, 
taking medications, and not bedridden.  
5.5.3.6 Serious Adverse Event (SAE) 
A serious adverse event (SAE) is an AE that: 
• 
Is fatal 
• 
Is life-threatening, meaning the patient was, in the view of the Investigator, at 
immediate risk of death from the reaction as it occurred, i.e., it does not include a 
reaction that, had it occurred in a more serious form or progressed, might have caused 
death 
• 
Is a persistent or significant disability or incapacity or substantial disruption of the 
ability to conduct normal life functions 
• 
Requires or prolongs inpatient hospitalization 
• 
Is a congenital anomaly or birth defect 
Other important medical events may be considered SAEs when, based upon appropriate 
medical judgment, they may jeopardize the patient and may require medical or surgical 
intervention to prevent one of the outcomes as listed (# 1-5 above) in this definition. 
All SAEs, including death due to any cause, that occur during this study and until 30 days 
after the last dose of study treatment, whether or not expected and regardless of causality, must 
be reported to the Medical Monitor immediately upon discovery of the event, using an SAE 
Form.  
The Medical Monitor will advise the Investigator regarding the nature of any further 
information or documentation that is required.  The Investigator should provide the following 
documentation at the time of notification if available: 
• 
SAE Form 
• 
AE (CRF) page 
• 
Concomitant and support medication pages 
• 
Relevant diagnostic reports 
• 
Relevant laboratory reports 
• 
Admission notes 
• 
Hospital discharge summary (when available). 
The Sponsor must notify FDA and all participating Investigators (i.e., all Investigators to 
whom the Sponsor is providing drug under its INDs or under any Investigator's IND) in an 
IND safety report of potential serious risks, from clinical trials or any other source, as soon as 
possible, but in no case later than 15 calendar days after the Sponsor determines that the 
information qualifies for reporting under paragraph (c)(1)(i), (c)(1)(ii), (c)(1)(iii), or (c)(1)(iv) 
of 21CFR 312.32. The Sponsor must identify all IND safety reports previously submitted to 

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FDA concerning a similar suspected adverse reaction, and must analyze the significance of 
the suspected adverse reaction in light of previous, similar reports or any other relevant 
information. 
Serious and unexpected suspected adverse reaction  
The Sponsor must report any suspected adverse reaction that is both serious and unexpected. 
The Sponsor must report an adverse event as a suspected adverse reaction only if there is 
evidence to suggest a causal relationship between the drug and the adverse event, such as: 
1. A single occurrence of an event that is uncommon and known to be strongly 
associated with drug exposure (e.g., angioedema, hepatic injury, Stevens-Johnson 
Syndrome); 
2. One or more occurrences of an event that is not commonly associated with drug 
exposure, but is otherwise uncommon in the population exposed to the drug (e.g., 
tendon rupture); 
3. An aggregate analysis of specific events observed in a clinical trial (such as known 
consequences of the underlying disease or condition under investigation or other 
events that commonly occur in the study population independent of drug therapy) that 
indicates those events occur more frequently in the drug treatment group than in a 
concurrent or historical control group. 
Submission of IND safety reports 
The Sponsor must submit each IND safety report in a narrative format or on FDA Form 3500A 
or in an electronic format that FDA can process, review, and archive. FDA will periodically 
issue guidance on how to provide the electronic submission (e.g., method of transmission, 
media, file formats, preparation and organization of files). The Sponsor may submit foreign 
suspected adverse reactions on a Council for International Organizations of Medical Sciences 
(CIOMS) I Form instead of a FDA Form 3500A. Reports of overall findings or pooled 
analyses from published and unpublished in vitro, animal, epidemiological, or clinical studies 
must be submitted in a narrative format. Each notification to FDA must bear prominent 
identification of its contents, i.e., "IND Safety Report," and must be transmitted to the review 
division in the Center for Drug Evaluation and Research or in the Center for Biologics 
Evaluation and Research that has responsibility for review of the IND. Upon request from 
FDA, the Sponsor must submit to FDA any additional data or information that the agency 
deems necessary, as soon as possible, but in no case later than 15 calendar days after receiving 
the request. 
5.5.3.7 Unexpected fatal or life-threatening suspected adverse reaction reports  
The Sponsor must also notify FDA of any unexpected fatal or life-threatening suspected 
adverse reaction as soon as possible but in no case later than 7 calendar days after the Sponsor's 
initial receipt of the information. 
5.5.3.8 Clinical Laboratory Assessments 
Hematological toxicities will be assessed in term of hemoglobin value, white blood cell, 
neutrophil, platelet, and lymphocyte count according to the NCI-CTCAE AE grading. 
Laboratory abnormalities (grade 1 and greater that are listed in the NCI-CTCAE V4.03) 
should be recorded on the AE page regardless of their causality. 

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5.5.4 Efficacy (Clinical) Measurements 
5.5.4.1 PSA assessment 
Rising levels of PSA in serum are associated with prostate cancer [9]. Currently, PSA testing 
of serum is a standard test for indicating further investigation for prostate cancer.   
A cutoff of 4.0 ng/mL has a sensitivity of 67.5-80% for detecting prostate cancer [10]. 
5.5.4.2 Treatment Failure 
Treatment failure will be assessed by the observance of PSA doubling less than 90 days or 
unacceptable toxicity as determined by the Investigator. 
5.6 Data Quality Assurance 
At the study sites, all CRFs will be manually reviewed for completeness by the Sponsor's 
Clinical Research Associates.  Site Staff will enter the required subject data into the provided 
Code of Federal Regulations (CFR) Part 11-compliant electronic data capture (EDC) system.  
Programmed computer edit checks will be run against the database to check for discrepancies 
and plausibility of the data.  All issues resulting from the computer-generated checks will be 
resolved according to the Sponsor's standard data management practices in conjunction with 
the medical monitor, clinical study personnel, and the study Investigators.  
6. Statistical Methods and Determination of Sample Size 
6.1 Statistical and Analytical Plans 
No formal statistical analysis will be performed, however, statistical derivation of all data will 
be derived by dose cohort and displayed for inspection. 
For the dose-escalation phase of the study, cohorts of 3 or 6 patients will be screened, 
registered and treated at each dose level. The actual sample size may vary depending on the 
incidence of DLT during Cycle 1 at a given dose level. Once the MTD/RP2D is determined, 
additional patients may be accrued to provide for 6 patients in the MTD cohort. 
Approximately, 18 patients will be screened, registered and treated in the trial.  
The primary safety analysis will assess MTD and AEs, clinical laboratory tests, and 
tolerability, based on the combined evaluation of immunogenicity and incidence of DLTs in 
each patient. 
6.2 Determination of Sample Size 
Cohorts of 3 or 6 patients will be screened and treated at each dose level. The actual sample 
size may vary depending on the incidence of DLT during the first cycle at a given dose level. 
Approximately 18 patients will be included and treated in the trial. 
7. Ethics 
7.1 Institutional Review Board (IRB) / Ethics Committee 
Before the start of the study, the study protocol, ICF, and/or other appropriate documents will 
be submitted to the IRB, in accordance with local legal requirements.  It is the responsibility 
of the Investigator to ensure that all aspects of the IRB review are conducted in accordance 

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with current local and U.S. regulations.  Sensei and the Investigator must inform each other in 
writing that all ethical and legal requirements have been met before the first patient is enrolled 
at the study site.   
7.2 Ethical Conduct of the Study 
The study will be conducted in accordance with the ethical principles of the current version of 
the Declaration of Helsinki.  The Sponsor and Investigator will comply with their 
responsibilities as defined in 21 CFR 312.50-312.70 and International Conference on 
Harmonization Guidance for Industry: E6 Good Clinical Practice (April 1996). 
7.3 Patient Information and Consent 
The Investigator will obtain informed consent from each patient enrolled in the study, in 
accordance with the U.S. Food and Drug Administration (FDA) regulations 21 CFR 50.20 - 
50.27 and the laws and regulations of the state in which the investigation is being conducted.   
The IRB must approve the ICF to be used by the Investigator.  It is the responsibility of the 
Investigator to ensure that informed consent is obtained from the patient or his/her guardian 
or legal representative before any activity or treatment is undertaken which is not part of 
routine care.  This includes, but is not limited to, the performance of diagnostic, screening, or 
therapeutic procedures and the administration of the first dose of study treatment.  The draft 
version of the ICF will be modified by each site and reviewed and approved in writing by 
Sensei prior to submission to the IRB.  The terms of the consent and when it was obtained 
must also be documented in the patient’s CRF. A second copy of the current ICF will be 
reviewed and signed by the patient to allow for patient re-screening on study if archived tumor 
tissue or fresh serum is initially negative for HAAH.  Over this 6-month interval, PSA levels 
can be obtained and if they have increased appreciably from the original screening visit and 
HAAH is positive in serum or tumor tissue, the patient may be enrolled in the study. The same 
archived tumor tissue will not be retested. 
Should a protocol amendment be made, the subject ICF may be revised to reflect the changes 
of the protocol.  If the ICF is revised, it is the responsibility of the Investigator to ensure that 
an amended ICF is reviewed and approved by the IRB and signed by all subjects subsequently 
entered in the study. 
7.4 Protocol Amendments 
Neither the Investigator nor Sensei will alter this study protocol without obtaining the 
agreement of the other.  Amendments will be made only in exceptional cases once the study 
has started at the discretion of Sensei with the agreement of the Investigator.  Changes must 
be agreed to in writing, and signed, by all parties concerned.  The changes then become part 
of the study protocol.  Any changes in the protocol, even local/site requirements, will be 
written in an amendment.  The IRB must be informed of amendments and, if necessary, 
approval must be sought for ethical aspects.  Approval of amendments must also be obtained 
from the local regulatory authority, if necessary. 
7.5 Confidentiality 
All local legal requirements regarding data protection will be enforced.  All study findings and 
documents will be regarded as confidential.  The Investigator and members of his/her research 
team must not disclose such information without prior written approval from Sensei.  The 
anonymity of participating patients must be maintained.  Throughout documentation and 
evaluation, the patients will be identified on CRFs and other documents submitted to Sensei 

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by their initials, birth date, and their patient number.  Documents that are not to be submitted 
to Sensei, and that identify the patient (e.g., the signed ICF), must be maintained in confidence 
by the Investigator.  The patients will be told that all study findings will be stored and handled 
in strictest confidence, according to local requirements.  Patients will be informed that 
authorized research Investigators and agents of the FDA, other recognized regulatory 
authorities, and authorized representatives of the Sponsor, Sensei, have the right to inspect 
their medical records. 
8. Investigators and Study Administrative Structure 
This is a Phase 1 trial involving study centers located in the United States. The Investigator(s) 
responsible for the conduct of the study at their site, in compliance with this Protocol, are 
identified on the Signature of Agreement Page (Appendix B).  
8.1 Sponsor Contacts 
All questions regarding the enrollment of patients, regulatory requirements for the conduct of 
the study, safety reporting, or study conduct should be addressed to the Medical Monitor: 
8.2 Data Handling and Recordkeeping 
8.2.1 Electronic Case Report Form (eCRF) 
Electronic case report forms will be provided via a Part 11 compliant database; patients will 
not be identified by name on any study documents.  Each patient shall be identified by the 
patient identifying number that will be assigned by the Sponsor. 
8.2.2 Maintenance of Study Records 
The Investigator must retain a copy of all study documents, including reports to the IRB, 
regulatory authorities, and Sensei in accordance with FDA regulations. 
The Investigator must maintain study documents: 
• 
for a minimum of two years following the date the marketing application (NDA/BLA) 
is approved for the indication for which the drug was investigated; or, 
• 
for a minimum of two years following the release date of the final report, if no 
marketing application is to be filed by Sensei, or if the marketing application is not 
approved for the indication for which the drug was investigated or is discontinued and 
the FDA has been notified; or, 
• 
for a minimum of 15 years after the completion or discontinuation of the study to be 
filed in support of the registration in the European Union. 
If the Investigator relocates, retires for any reason, or withdraws from the study, the study 
records may be transferred to an acceptable designee, such as another Investigator, another 
institution, or to Sensei.  The Investigator must obtain Sensei’s written permission before 
disposing of or transferring any records. 
8.3 Final Report 
Upon terminating the study, the Investigator will submit a final report to the IRB in keeping 
with local IRB regulations.  This report should include any deviations from the protocol, the 
number and types of patients evaluated, the number of patients who discontinued, including 
reasons, results of the study, AEs, and a conclusion summarizing the results. 

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If requested by the Investigator, at the completion of the study and following analysis of the 
data, Sensei will supply a tabulated listing of data and a final clinical statistical report.  A copy 
of the final study report and corrected CRFs, including a receipt to be returned to the Sensei 
Clinical Monitor, will be provided to each Investigator following its release by Sensei. 
8.4 Publication and Use of Study Findings 
By signing the study protocol, the Investigator agrees with the use of results of the study for 
the purposes of national and international registration, publication, and information for 
medical and pharmaceutical professionals.  If necessary, the authorities will be notified of the 
Investigator's name, address, qualifications, and extent of involvement.  Sensei will prepare 
an Integrated Clinical/Statistical Report.  Any publication/presentation of data must include 
the entire study population.  Submission of data for publication/presentation will be 
coordinated and approved by Sensei in collaboration with the Investigator.  Sensei will 
determine authorship of any publication by enrollment in consultation with the principal 
Investigator. 
8.5 Liability and Insurance 
The Sponsor will take out reasonable third-party liability insurance coverage in accordance 
with all local indemnification requirements.  The civil liability of the Investigator, the persons 
instructed by him, the hospital, practice, or institute in which they are employed, and the 
liability of the Sponsor in respect of financial loss due to personal injury and other damage, 
which may arise as a result of the carrying out of this study, are governed by the applicable 
law.  As a precautionary measure, the Investigator, the persons instructed by him and the 
hospital, practice or institute are included in such cover in regards to work done by them in 
carrying out this study to the extent that the claims are not covered by their own professional 
indemnity insurance.  The Sponsor will arrange for patients participating in this study to be 
insured against financial loss due to personal injury caused by the pharmaceutical products 
being tested or by medical steps taken in the course of the study.  Such insurance is taken out 
by the Sponsor in accordance with regulations in the country concerned.  To the extent that 
payments are made under such insurance, the right to claim damages from the Sponsor 
extinguishes. 
 
 

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9. REFERENCE LIST  
1. Jia, S., W.J. VanDusen, R.E. Diehl, N.E. Kohl, R.A. Dixon, K.O. Elliston, A.M. Stern, 
and P.A. Friedman. 1992. cDNA cloning and expression of bovine aspartyl 
(asparaginyl) beta-hydroxylase. The Journal of Biological Chemistry 267:14322-
14327. 
2. Lavaissiere, L., S. Jia, M. Nishiyama, S. de la Monte, A.M. Stern, J.R. Wands, and 
P.A. Friedman. 1996. Overexpression of human aspartyl(asparaginyl)beta-
hydroxylase in hepatocellular carcinoma and cholangiocarcinoma. The Journal of 
Clinical Investigation 98:1313-1323. 
3. Shimoda, M., Y. Tomimaru, K.P. Charpentier, H. Safran, R.I. Carlson, and J. Wands. 
2012. Tumor progression-related transmembrane protein aspartate-beta-hydroxylase 
is a target for immunotherapy of hepatocellular carcinoma. Journal of Hepatology 
56:1129-1135. 
4. De Berardinis, P., R. Sartorius, C. Fanutti, R.N. Perham, G. Del Pozzo and G. 
Guardiola. 2000. Phage display of peptide epitopes from HIV-1 elicits strong cytolytic 
responses in vitro and in vivo. Nature Biotechnology 18(8):873-876. 
5. De Berardinis, P., L. D’Apice, A. Prisco, M.N. Ombra, P. Barba, G. Del Pozzo, S. 
Petukhov, P. Malik, R.N. Perham, and J. Guardiola. 1999. Recognition of HIV-
derived B and T cell epitopes displayed on filamentous phages. Vaccine 17 (11-
12):1434-1441. 
6. Di Marzo Veronesse, F., A.E. Willis, C. Boyer-Thompson, E. Appella and R.N. 
Perham. 1994. Structural Mimicry and Enhanced Immunogenicity of Peptide 
Epitopes Displayed on Filamentous Bacteriophage: The V3 loop of HIV-1 gp120. 
Journal of Molecular Biology 243(2):167-172. 
7. Perham, R.N., T.D. Terry, A.E. Willis, J. Greenwood, F. di Marzo Veronesse and E. 
Appella. 1995. Engineering a peptide epitope display system on filamentous 
bacteriophage. FEMS Microbiology Reviews 17(1-2):25-31. 
8. Guidance for Industry: Estimating the maximum safe starting dose in initial clinical 
trials for therapeutics in adult healthy volunteers. U.S. Department of Health and 
Human Services; Food and Drug Administration Center for Drug Evaluation and 
Research (CDER); July 2005, Pharmacology and Toxicology 
9. Stamey TA, Yang N, Hay AR, et al. Prostate-specific antigen as a serum marker for 
adenocarcinoma of the prostate. N Engl J Med. Oct 8 1987;317(15):909-16 
10. (http://emedicine.medscape.com/article/457394-overview#aw2aab6b8 
11. Wolchok JD, Hoos A, O'Day S, et al. Guidelines for the evaluation of immune therapy 
activity in solid tumors: immune-related response criteria. Clin Cancer Res. 
2009;15(23):7412–7420. 
12. Stephenson, A., Kattan, M.,   Eastham, J., Dotan, Z., Bianco Jr, F., Lilja, H., and 
Scardino, P. 2006. Deﬁning Biochemical Recurrence of Prostate Cancer After Radical 
Prostatectomy: A Proposal for a Standardized Deﬁnition. J Clin Oncol 24:3973-3978. 
 
 

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10. LIST OF APPENDICES 
Appendix 
Title 
A 
Eastern Cooperative Oncology Group Performance Status 
(ECOG) 
B 
Principal Investigator Signature of Agreement Page 
 
 

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APPENDIX A: ECOG PERFORMANCE STATUS 
ECOG PERFORMANCE STATUS* 
GRADE 
ECOG 
0 
Fully active, able to carry on all pre-disease performance without restriction 
1 
Restricted in physically strenuous activity but ambulatory and able to carry out work of 
a light or sedentary nature, e.g., light house work, office work 
2 
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 
Capable of only limited self-care, confined to bed or chair more than 50% of waking 
hours 
4 
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. 
 
 

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APPENDIX B: PRINCIPAL INVESTIGATOR SIGNATURE OF AGREEMENT 
PAGE 
 
INVESTIGATORS AGREEMENT 
This document is a confidential communication of Sensei Biotherapeutics, Inc. (Sensei).  The 
recipient agrees that no unpublished information contained herein will be published or disclosed 
without prior written permission of Sensei.  However, this document may be disclosed to 
appropriate Institutional Review Boards, ethics review committees, or authorized representatives of 
the Investigator or of boards of health under the condition that they are requested to respect the 
confidentiality of the document. 
 
The signature of the Principal Investigator below constitutes his/her agreement to comply with the 
contents of this Protocol. 
 
 
 
 
Principal Investigator’s Name 
 
Principal Investigator’s Title 
 
 
 
 
 
 
Principal Investigator’s Address 
 
 
 
 
 
Principal Investigator’s Signature 
 
Date