A Phase 1b/2 Open-Label, Dose Escalation & Expansion Study of Orally Administered Viracta (VRx)-3996 & Valganciclovir in Subjects With Epstein-Barr Virus-Associated Lymphoid Malignancies
Phase: PHASE1
Conditions: Epstein-Barr Virus-Associated Lymphoma, Lymphoproliferative Disorders
Sponsor: Viracta Therapeutics, Inc.

This document contains confidential information of Viracta Therapeutics, Inc. 
Do not copy or distribute without written permission from the Sponsor. 
TITLE PAGE 
 
CLINICAL STUDY PROTOCOL 
A Phase 1b/2 Open-Label, Dose Escalation and Expansion Study of 
Orally Administered VRx-3996 and Valganciclovir in Subjects with 
Epstein-Barr Virus-Associated Lymphoid Malignancies 
 
Protocol Number: 
VT3996-201 
Sponsor: 
Viracta Therapeutics, Inc. 
Sponsor Contact: 
Lisa Rojkjaer, MD 
Medical Monitor: 
John Gutheil, MD 
Study Drugs: 
Nanatinostat (VRx-3996) and Valganciclovir 
IND Number: 
132679 
Version: 
Amendment 5.0 
Date: 
07 January 2021 
 
 

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TABLE OF CONTENTS 
 
 
TITLE PAGE ...................................................................................................................................1 
ABBREVIATIONS .........................................................................................................................6 
SPONSOR’S PROTOCOL APPROVAL SIGNATURE PAGE ...................................................10 
INVESTIGATOR’S SIGNATURE PAGE ....................................................................................11 
PROTOCOL SYNOPSIS...............................................................................................................12 
1. BACKGROUND .....................................................................................................................14 
1.1. 
EBV and Cancer ..........................................................................................................14 
1.2. 
EBV-Associated Lymphomas ......................................................................................14 
1.3. 
Use of Antivirals in EBV-Associated Lymphomas .....................................................15 
1.4. 
Human Herpesviruses ..................................................................................................15 
1.5. 
Rationale for the Combination of HDAC Inhibitors and Antivirals for the 
Treatment of EBV-Associated Lymphomas ................................................................16 
1.6. 
HDAC Enzymes...........................................................................................................17 
1.7. 
HDAC Inhibitors ..........................................................................................................17 
1.8. 
VRx-3996 (nanatinostat) ..............................................................................................18 
1.9. 
Valganciclovir ..............................................................................................................20 
1.10. Rationale for Starting Dose ..........................................................................................20 
1.11. Rationale for Study ......................................................................................................20 
1.12. Potential Risks and Benefits ........................................................................................21 
1.12.1. Potential Risks .................................................................................................21 
1.12.2. Potential Benefits .............................................................................................21 
2. OBJECTIVES ..........................................................................................................................21 
2.1. 
Primary Objective ........................................................................................................21 
2.2. 
Secondary Objectives ...................................................................................................22 
2.3. 
Exploratory Objectives ................................................................................................22 
3. STUDY DESIGN.....................................................................................................................22 
3.1. 
Phase 1b (Dose Escalation) ..........................................................................................23 
3.1.1. Cohort Size.......................................................................................................23 
3.1.2. Cohort Enrollment ...........................................................................................23 
3.1.3. Cohort Doses and Regimens ............................................................................23 
3.1.4. Dose Escalation Procedure ..............................................................................24 
3.1.5. Dose Limiting Toxicity ....................................................................................24 
3.1.6. Continued Study Drugs Following DLT ..........................................................25 
3.1.7. Maximum Tolerated Dose ...............................................................................25 
3.1.8. Dose Increases for Individual Patients .............................................................25 
3.1.9. Replacement of Patients during Phase 1b Portion of Study ............................26 
3.2. 
Phase 2 (Dose Expansion) ...........................................................................................26 
3.2.1. Phase 2 Sample Size ........................................................................................26 
3.2.2. Phase 2 Dose ....................................................................................................26 
3.2.3. Assessment of Toxicity During Phase 2 Dose Expansion ...............................26 
3.2.4. Phase 2 Study Drug(s) Administration Schedule .............................................27 
3.3. 
Tablet Cohort ...............................................................................................................27 
3.4. 
Continuation of VRx-3996/Valganciclovir ..................................................................28 
3.5. 
Dose Adjustments/Modifications/Delays ....................................................................28 
3.6. 
Central Pathology Review ...........................................................................................28 

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3.7. 
Laboratory Procedures .................................................................................................28 
3.8. 
Central Radiology Review ...........................................................................................29 
3.9. 
Central ECG Review ....................................................................................................29 
3.10. Safety Review Committee (SRC) ................................................................................29 
3.11. Concomitant Medications, Treatments, and Procedures ..............................................29 
3.11.1. Cytochrome P450 Substrates ...........................................................................30 
3.11.2. Transporter Substrates and Inhibitors ..............................................................30 
3.12. Prophylactic Medications, Treatments, and Procedures ..............................................30 
3.13. Rescue Medications, Treatments, and Procedures .......................................................31 
3.14. Prohibited Cancer Treatments......................................................................................31 
3.15. Discontinuation of VRx-3996/Valganciclovir .............................................................31 
3.16. Restarting Study Drugs at Relapse ..............................................................................32 
3.17. Removal of Patients from Study Follow-Up ...............................................................32 
3.18. Replacement of Patients During Phase 2 Portion of Study ..........................................32 
3.19. Handling of Patient Withdrawal or Termination .........................................................32 
3.20. Premature Termination or Suspension of Study ..........................................................32 
4. STUDY ELIGIBILITY ............................................................................................................33 
4.1. 
Inclusion Criteria .........................................................................................................33 
4.2. 
Exclusion Criteria ........................................................................................................34 
5. INVESTIGATIONAL PRODUCTS .......................................................................................35 
5.1. 
VRx-3996 Drug Substance ..........................................................................................35 
5.1.1. Acquisition .......................................................................................................36 
5.1.2. Dosage Form ....................................................................................................36 
5.1.3. Composition .....................................................................................................36 
5.1.4. Product Packaging ...........................................................................................37 
5.1.5. Product Storage and Stability...........................................................................37 
5.1.6. Dosing and Administration ..............................................................................37 
5.1.7. Dietary Requirements ......................................................................................37 
5.1.8. Dose Adjustments/Modifications/Delays ........................................................38 
5.2. 
Valganciclovir ..............................................................................................................39 
5.2.1. Acquisition .......................................................................................................39 
5.2.2. Product Storage and Stability...........................................................................39 
5.2.3. Dosing and Administration ..............................................................................39 
5.2.4. Dietary Requirements ......................................................................................40 
5.2.5. Dose Adjustments/Modifications/Delays ........................................................40 
5.2.6. Drug Interactions .............................................................................................40 
5.3. 
Missed Doses ...............................................................................................................41 
5.4. 
Vomited Doses .............................................................................................................41 
5.5. 
Assessment of Study Drug Compliance ......................................................................41 
5.6. 
Study Drug Accountability ..........................................................................................41 
6. STUDY PROCEDURES AND SCHEDULE ..........................................................................41 
6.1. 
Informed Consent.........................................................................................................41 
6.2. 
Patient Registration ......................................................................................................41 
6.3. 
Study Specific Procedures ...........................................................................................41 
6.3.1. End of Treatment Visit.....................................................................................42 
6.3.2. Safety Follow-Up Visit ....................................................................................42 

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6.3.3. Survival and Follow-up Assessment ................................................................42 
6.3.4. Unscheduled Visit ............................................................................................42 
6.4. 
Clinical Laboratory Evaluations ..................................................................................42 
6.4.1. Pharmacokinetics .............................................................................................42 
6.4.2. Exploratory Biomarkers ...................................................................................44 
7. SCHEDULE OF EVENTS ......................................................................................................44 
8. STUDY COMPLETION .........................................................................................................47 
8.1. 
Early Study Termination ..............................................................................................47 
8.2. 
Patient Discontinuation ................................................................................................47 
8.3. 
Lost to Follow-Up ........................................................................................................47 
9. ASSESSMENT OF SAFETY ..................................................................................................47 
9.1. 
Specification of Safety Parameters ..............................................................................47 
9.1.1. Adverse Event (AE) Definition .......................................................................47 
9.1.2. Abnormal Laboratory Tests .............................................................................48 
9.1.3. Definition of Serious Adverse Events (SAE) ..................................................48 
9.2. 
Classification of an Adverse Event ..............................................................................48 
9.2.1. Severity of Event ..............................................................................................48 
9.2.2. Relationship to Study Drugs ............................................................................48 
9.2.3. Expectedness ....................................................................................................49 
9.3. 
Time Period for AE Reporting .....................................................................................49 
10. ASSESSMENT OF EFFICACY..............................................................................................49 
11. REPORTING PROCEDURES ................................................................................................49 
11.1. Serious Adverse Event Reporting ................................................................................49 
11.2. Reporting of Pregnancy ...............................................................................................50 
11.3. Overdose ......................................................................................................................50 
12. STATISTICAL CONSIDERATIONS.....................................................................................50 
12.1. Analysis Datasets .........................................................................................................50 
12.2. Description of Statistical Methods ...............................................................................50 
12.3. Analysis of the Primary Endpoints ..............................................................................51 
12.3.1. Safety Profile ...................................................................................................51 
12.3.2. Recommended Phase 2 Dose ...........................................................................51 
12.4. Analysis of the Secondary Endpoints ..........................................................................52 
12.4.1. Pharmacokinetics (PK) ....................................................................................52 
12.4.2. Time to Response, PFS, and OS ......................................................................52 
12.5. Analysis of Exploratory Endpoints ..............................................................................53 
12.6. Baseline Descriptive Statistics .....................................................................................53 
13. CLINICAL MONITORING ....................................................................................................53 
14. SOURCE DOCUMENTS AND ACCESS TO SOURCE DATA/DOCUMENTS .................53 
15. QUALITY ASSURANCE AND QUALITY CONTROL .......................................................53 
16. ETHICS/PROTECTION OF HUMAN PATIENTS ...............................................................53 
16.1. Ethical Standard ...........................................................................................................53 
16.2. Institutional Review Board ..........................................................................................54 
16.3. Patient and Data Confidentiality ..................................................................................54 
16.4. Research Use of Stored Human Samples, Specimens or Data ....................................54 
16.5. Future Use of Stored Specimens ..................................................................................54 
17. DATA HANDLING AND RECORD KEEPING ...................................................................55 

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17.1. Data Collection Responsibilities ..................................................................................55 
17.2. Study Records Retention ..............................................................................................55 
17.3. Publication and Data Sharing Policy ...........................................................................55 
18. COVID-19 PANDEMIC ..........................................................................................................55 
18.1. Introduction ..................................................................................................................55 
18.2. Protocol Modifications.................................................................................................56 
19. LITERATURE REFERENCES ...............................................................................................57 
APPENDIX ....................................................................................................................................59 
 
LIST OF TABLES 
Table 1: 
Human Herpesviruses ................................................................................................ 16 
Table 2: 
HDAC Enzymes16 ..................................................................................................... 17 
Table 3: 
Selected HDAC Inhibitors in Clinical Use or Development* ................................... 18 
Table 4: 
PK Parameters of VRx-3996 ..................................................................................... 19 
Table 5: 
Phase 1b Cohort Doses .............................................................................................. 24 
Table 6: 
Early Stopping Boundaries for Toxicity ................................................................... 27 
Table 7:  
Patient Stratification by Risk (adapted from Coiffier 2008)24 .................................. 30 
Table 8:  
Recommended Rasburicase Dosing (adapted from Coiffier 2008)24 ........................ 31 
Table 9: 
Drug Substance Properties ........................................................................................ 36 
Table 10: 
Quantitative Composition of VRx-3996 Capsules .................................................... 36 
Table 11: 
Quantitative Composition of Film-Coated, Immediate-Release VRx-3996 Tablets 
 
(5 and 10 mg Strengths) ............................................................................................ 37 
Table 12: 
Requirements for Dose Hold Secondary to Non-Hematologic Toxicity .................. 38 
Table 13: 
Valganciclovir Dose Adjustments for Adult Renal Impairment ............................... 39 
Table 14: 
Pharmacokinetic Sampling and ECG Schedule for Valganciclovir and VRx-3996  43 
Table 15: 
Schedule of Events .................................................................................................... 44 
Table 16: 
Conversions for ECOG and Karnofsky Grades30 ...................................................... 59 
Table 17: 
Established and Other Potentially Significant Drug Interactions with Ganciclovir* 60 
Table 18a:  Examples of Sensitive Substrates of CYP3A ............................................................ 61 
Table 18b:  Examples of Strong Inhibitors of P-gp and BCRP Transporters ............................... 61 
LIST OF FIGURES 
Figure 1: 
Structural Formula and Key Features of VRx-3996 ................................................. 35 
 

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ABBREVIATIONS 
Abbreviation 
Description 
Ab 
antibody 
AE 
adverse event 
AIDS 
acquired immunodeficiency syndrome 
ALL 
acute lymphoblastic leukemia 
ALT 
alanine aminotransferase 
ANC 
absolute neutrophil count 
AST 
asparagine aminotransferase 
AUC 
area under the curve 
AUC0-∞  
area under the concentration-time curve from administration to infinity 
AUC0-t 
area under the concentration-time curve from administration to time t 
BID 
twice daily 
CBC 
complete blood count 
CFR 
Code of Federal Regulations 
CHR-3996 
former name for VRx-3996 
CI 
confidence interval 
CL/F 
apparent clearance  
CLL 
chronic lymphocytic leukemia  
Cmax 
maximum concentration 
CMV 
cytomegalovirus 
CNS 
central nervous system 
CR 
complete response 
CT 
computed tomography 
CTCAE 
Common Terminology Criteria for Adverse Events 
CTL 
cytotoxic T-lymphocyte 
CV 
coefficient of variation 
CV% 
percent coefficient of variation 
DLBCL 
diffuse large B-cell lymphoma 
DLT 
dose-limiting toxicity 
DNA 
deoxyribonucleic acid 
DoR 
duration of response 
EBER 
Epstein-Barr Virus-encoding region 

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Abbreviation 
Description 
EBV 
Epstein-Barr Virus 
EC 
Ethics Committee 
ECG 
electrocardiogram 
ECOG 
Eastern Cooperative Oncology Group 
eCRF 
electronic case report forms 
eGFR 
estimated glomerular filtration rate 
ET 
End of Treatment 
FDA 
Food and Drug Administration 
FISH 
fluorescence in situ hybridization 
GCP 
Good Clinical Practice 
GvHD 
graft versus host disease 
HCT 
hematocrit 
HDAC 
histone deacetylase 
HGB 
hemoglobin 
HHV 
human herpesvirus 
HIV 
human immunodeficiency virus 
HL 
Hodgkin’s lymphoma 
HLA 
human leukocyte antigen 
HSV 
herpes simplex virus 
ICF 
informed consent form 
ICH 
International Council for Harmonisation 
ICMJE 
International Committee of Medical Journal Editors 
INR 
international normalized ratio 
IP 
investigational product 
IRB 
Institutional Review Board 
IV 
intravenous 
KPS 
Karnofsky Performance Status 
LDH 
lactate dehydrogenase 
MCH 
mean corpuscular hemoglobin 
MCV 
mean corpuscular volume 
MDRD 
Modification of Diet in Renal Disease 
MedDRA 
Medical Dictionary for Regulatory Activities 

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Abbreviation 
Description 
MMF 
mycophenolate mofetil 
MRI 
magnetic resonance imaging 
MTD 
maximum tolerated dose 
NCI 
National Cancer Institute  
NHL 
non-Hodgkin’s lymphoma 
NK 
natural killer 
ORR 
overall response rate 
OS 
overall survival 
PBMC 
peripheral blood mononuclear cell 
PCR 
polymerase chain reaction 
PET 
positron emission tomography 
PFS 
progression-free survival 
PK 
pharmacokinetics 
PLT 
platelet 
PO 
by mouth 
PR 
partial response 
PS 
performance status 
PT 
prothrombin time 
PTLD 
post-transplant lymphoproliferative disease 
PTT 
partial thromboplastin time 
QD 
once daily 
qPCR 
quantitative polymerase chain reaction 
QTcF 
corrected QT interval using Fridericia’s method 
RBC 
red blood cell 
RNA 
ribonucleic acid 
RP2D 
recommended Phase 2 dose 
SAE 
serious adverse event 
SAHA 
suberoylanilide hydroxamic acid 
SD 
stable disease 
SGOT 
serum glutamic oxaloacetic transaminase 
SGPT 
serum glutamic-pyruvic transaminase 
SOP 
Standard Operating Procedure 

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Abbreviation 
Description 
SRC 
Safety Review Committee 
t½ 
terminal elimination half-life 
TK 
thymidine kinase 
TLS 
tumor lysis syndrome 
Tmax 
time to maximum concentration 
TTR 
time to response 
ULN 
upper limit of normal 
UPS 
United Parcel Service 
US 
United States 
Vz/F 
apparent volume of distribution 
WBC 
white blood cell 
WHO 
World Health Organization 
 
 

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INVESTIGATOR’S SIGNATURE PAGE 
By signing below, the Investigator agrees to adhere to the protocol as written and agrees that any 
changes to the protocol must be approved by Viracta Therapeutics, Inc. before seeking approval 
from the Institutional Review Board (IRB). 
The study will be conducted in accordance with the current International Council for 
Harmonisation (ICH) Guidelines, the Guidelines for Good Clinical Practice (GCP), the 
Declaration of Helsinki, and local ethical and regulatory requirements. 
The information contained in this protocol is proprietary and provided to me in confidence, 
and may not be disclosed to any other party, in any form, without prior authorization from 
Viracta Therapeutics, except to the extent necessary for the conduct of the study at this study 
site. 
__________________________________________________  
Investigator - Signature 
Date 
__________________________________________________  
Investigator - Printed name 
__________________________________________________  
Institution 
__________________________________________________  
Address 

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PROTOCOL SYNOPSIS 
Title A Phase 1b/2 Open-Label, Dose Escalation and Expansion Study of 
Orally Administered VRx-3996 and Valganciclovir in Subjects 
with Epstein-Barr Virus-Associated Lymphoid Malignancies 
Sponsor Study No. VT3996-201  
Phase 1b/2 
Sponsor Viracta Therapeutics, Inc. 
Study Drug VRx-3996 (nanatinostat) and Valganciclovir 
Study Population Relapsed/refractory, pathologically confirmed Epstein-Barr 
virus-positive (EBV+) lymphoid malignancy or lymphoproliferative 
disease regardless of histologic subtype. 
Primary Objectives  • Determine the safety and tolerability 
of VRx-3996/valganciclovir 
• Determine a recommended Phase 2 dose (RP2D) 
of VRx-3996/valganciclovir 
• Assess activity based on overall response rate (ORR) 
Secondary Objectives • Evaluate pharmacokinetic (PK) parameters of varying doses of 
VRx-3996 in capsule and in tablet form 
• Evaluate PK parameters of varying doses of valganciclovir 
• Evaluate time to response (TTR) 
• Evaluate duration of response (DoR) 
• Determine progression-free survival (PFS) and overall survival 
(OS) 
Exploratory Objectives • Evaluate changes in viral loads (cytomegalovirus, EBV) by 
quantitative polymerase chain reaction (qPCR) with treatment, 
where applicable 
• Evaluate EBV latency/lytic profile 
• Evaluate changes in histone acetylation in peripheral blood 
mononuclear cells (PBMCs) 
• Evaluate immunophenotype and immune function in PBMCs 
Treatment Regimen VRx-3996 by mouth (PO) once daily (QD) or twice daily (BID) 
Valganciclovir PO QD or BID 

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Study Design An open-label, 2-part, Phase 1b/2 study to define a RP2D 
of VRx-3996 in combination with valganciclovir (Phase 1b) 
designed to evaluate the efficacy of this combination in 
relapsed/refractory EBV+ lymphomas (Phase 2). Phase 1b 
(dose escalation) will follow a modified oncology 3+3 design. 
Phase 2 (dose expansion) will evaluate the RP2D in patients with 
EBV+ lymphomas or lymphoproliferative disease using capsule 
and tablet forms of VRx-3996. 
All patients (Phase 1b and 2) will be assessed for response using 
imaging modalities appropriate for their specific lymphomas. 
Number of Patients Phase 1b: 25 
Phase 2: 30 patients. An additional cohort of 10 patients will be 
enrolled after the 30 phase 2 patients are enrolled. These 
10 patients will meet the same inclusion/exclusion criteria of the 
Phase 2 cohort, but will receive VRx-3996 in the tablet formulation 
instead of capsules. 
Number of Sites ~30 
Key Inclusion Criteria 
(see Section 4.1 for 
complete list of criteria) 
• Age 18+ years 
• Relapsed/refractory, pathologically confirmed EBV+ lymphoid 
malignancy or lymphoproliferative disease regardless of 
histologic subtype 
• Absence of available therapy with reasonable likelihood of cure 
or significant clinical benefit 
Key Exclusion Criteria 
(see Section 4.2 for 
complete list of criteria) 
• Known primary central nervous system (CNS) lymphoma 
• CNS metastases or leptomeningeal disease unless appropriately 
treated and neurologically stable for at least 4 weeks 
• Active, uncontrolled bacterial, viral, or fungal infection(s) 
requiring systemic therapy 
• Refractory graft versus host disease (GvHD) not responding 
to treatment (e.g., steroid refractory and not responding to 
second-line agents) 
• Positive hepatitis B core antibody or surface antigen unless 
quantitative DNA PCR is negative and patient will be receiving 
prophylaxis for reactivation 
• Positive hepatitis C virus on RNA PCR (if serology is positive) 
• Known history of human immunodeficiency virus (HIV) 
infection 
 
 

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1. 
BACKGROUND 
1.1. 
EBV and Cancer 
Epstein-Barr virus (EBV), a member of the γ-herpesvirus family, was the first virus directly 
implicated in the development of a human tumor,1 and is formally classified as a carcinogenic 
agent by the World Health Organization (WHO). Primary infection with EBV typically occurs in 
childhood and is generally asymptomatic; however, infection later in life may manifest as 
infectious mononucleosis.2 Once infected, individuals remain life-long carriers of the virus, with 
>90% of the world’s population asymptomatically infected with EBV. 
Latent infection and intermittent reactivation are 2 important characteristics of the EBV 
lifecycle. The maintenance of latent EBV infection requires the expression of a small subset of 
genes, and specific expression patterns (Types I–III) of these genes are associated with specific 
EBV-driven malignancies.3 EBV has been shown to infect B-cells, T/natural killer (NK)-cells, 
and epithelial cells, though its greatest predilection is for B-cells.3,4 EBV has been associated 
with a wide spectrum of human malignancies, though B-cell lymphomas are the most common 
and include Hodgkin’s lymphoma (HL), Burkitt’s lymphoma, post-transplant 
lymphoproliferative diseases (PTLDs), lymphomatoid granulomatosis, senile EBV-associated 
B-cell lymphoproliferative disorders, and many acquired immune deficiency syndrome 
(AIDS)-associated B-cell lymphomas.3 
1.2. 
EBV-Associated Lymphomas 
EBV-associated lymphomas are a heterogeneous group of malignancies that harbor latent EBV 
within the tumor. Within a specific histologic subtype of lymphoma, the frequency of EBV 
positivity may vary considerably. Diffuse large B-cell lymphoma (DLBCL) is rarely EBV+, 
whereas 30% of HLs within North America are EBV+ and endemic Burkitt’s lymphomas are 
almost always EBV+.5 
The risk for developing an EBV-associated lymphoma is higher in the setting of 
immunodeficiency, as is present in patients with human immunodeficiency virus (HIV), 
congenital immunodeficiencies, post-transplant immunosuppression, or chronic active EBV 
infection. 
EBV-associated lymphomas express a limited number of viral genes, with latency expression 
patterns associated with specific lymphoma subtypes.2 The limited expression of EBV genes 
may allow for persistence of the viral DNA in cells by restricting the visibility of the virus to the 
immune system. Supportive of this concept is the observation that lymphomas in patients with 
impaired immune function are more likely to express a greater number of viral genes. 
EBV-associated lymphomas in patients who are immunosuppressed may respond to therapies 
that improve immune function such as reduced immunosuppression (e.g., transplant patients) 
or adoptive immunotherapy.5 In contrast, EBV-associated lymphomas that arise in patients who 
are immunocompetent generally express fewer viral genes, and as a result are less prone to 
immune attack. 
While outcomes vary based on the specific EBV-associated malignancy, given the tumors 
associated with EBV (e.g., HL, Burkitt’s lymphoma, DLBCL, lymphomatoid granulomatosis, 
primary DLBCL of the central nervous system (CNS), and a number of T-cell based 
malignancies), effective regimens are only available for a subset of affected patients. 

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The presence of EBV in lymphomas is a poor prognostic indicator. Across a series of patients 
with DLBCL, those who were EBV+ generally presented more aggressive disease, had lower 
response rates to first-line therapy, and poorer progression-free and overall survival (OS) times.6 
In a meta-analysis evaluating survival outcomes across several lymphoma types (HL, DLBCL, 
T/NK-cell lymphoma, peripheral T-cell lymphoma), EBV+ disease was associated with 
significantly worse OS times.7 
1.3. 
Use of Antivirals in EBV-Associated Lymphomas 
Several antiviral compounds have been tested in the clinic against EBV-associated lymphomas, 
and in general, reproducible activity has been difficult to document.2 Antivirals that require the 
presence of functional viral thymidine kinase (TK) or viral protein kinase, such as the synthetic 
nucleosides ganciclovir, famciclovir, acyclovir, valaciclovir (a prodrug of acyclovir), 
and valganciclovir (a prodrug of ganciclovir) are less effective at eliminating EBV in chronically 
infected hosts because the virus can persist in a latent state of infection and lytic-phase proteins, 
including viral kinases, are required to convert these drugs to active antivirals.2 Foscarnet 
and cidofovir are active against viral DNA polymerase and are not dependent on expression of 
the viral kinases. As such, these antivirals have shown some activity against EBV-associated 
tumors both as single agents and in combination with the anti-CD20 monoclonal antibody 
rituximab. 
1.4. 
Human Herpesviruses 
There are 9 distinct herpesviruses known to cause disease in humans. These viruses are further 
subdivided into 3 subfamilies as outlined in Table 1. 
Among the herpesviruses, only members of the γ family (namely EBV and Kaposi's associated 
human herpesvirus (HHV-8) have been associated with the development of malignancies. 
As outlined under Section 1.2 and in Table 1, EBV-associated malignancies are typically of 
lymphoid nature (e.g., Burkitt’s lymphoma, PTLD, and others). Similarly, primary effusion 
lymphoma and Kaposi's sarcoma are known to be driven by HHV-8. 
The initial lytic infection caused by EBV and HHV-8 is generally cleared within a few weeks via 
a robust cytotoxic T-lymphocyte (CTL) response in immunocompetent individuals. However, 
a few infected cells survive and the virus down-regulates lytic genes and enters latency, which 
persists for the life of the infected host. However, viral reactivation can periodically occur during 
immunodeficiency states that may be associated, in some patients, with the development of 
malignancy. Immunodeficiency can be related to HIV infection, a known risk factor for the 
development of EBV and/or HHV-8 related malignancy3,5(Table 1). 
Post-transplant immunosuppression is yet another setting permissive for the development 
of EBV and/or HHV-8 related PTLD. Keys to the development of cancer are the type of 
immunosuppressant used, the total drug exposure (dosage and duration of dosing), and type 
of organ transplant, as well as genetic and pathogenic causes.8 
The immunosuppressive agents typically used in these settings include corticosteroids, 
calcineurin inhibitors (e.g., cyclosporine and tacrolimus), the antithymocyte globulins, 
and others.8,9 Post-transplant immunosuppression is also known to cause the reactivation of 
α herpesviruses (herpes simplex virus [HSV]-1 and -2, and Varicella Zoster Virus) and β 
herpesviruses (cytomegalovirus [CMV] and HHV-6).9 

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Because of this close interplay between the oncogenic viruses (namely EBV and HHV-8), 
immunodeficiency states (HIV or drug-induced) and reactivation of non-various human 
herpesviruses (Table 1), of non-γ human herpesviruses, both α and β, and the diseases that 
such -γ human herpesviruses can cause in this patient population, a close monitoring of viral 
reactivation for all herpesviruses with circulating quantitative polymerase chain reaction (qPCR) 
tests is clearly needed.  
Table 1: 
Human Herpesviruses 
Virus 
Family 
Primary Target 
Primary pathophysiology 
Latency site 
HSV-1 
α 
Mucoepithelial 
Oral and/or genital herpes 
Neuron 
HSV-2 
α 
Mucoepithelial 
Oral and/or genital herpes 
Neuron 
Varicella 
zoster  
α 
Mucoepithelial 
Chickenpox and shingles 
Neuron 
CMV 
β 
Monocytes, 
lymphocytes, 
epithelial cells 
Infectious mononucleosis-like syndrome, 
retinitis 
Monocyte, 
lymphocyte 
HHV-6A 
and 6B 
β 
T cells 
Sixth disease (roseola infantum or exanthem 
subitum) 
T cells 
HHV-7 
β 
T cells 
drug-induced hypersensitivity, encephalopathy, 
hemiconvulsion-hemiplegia-epilepsy 
syndrome, hepatitis infection, postinfectious 
myeloradiculoneuropathy, pityriasis rosea, and 
the reactivation of HHV-4, leading to 
"mononucleosis-like illness" 
T cells 
EBV 
γ 
B cells, 
epithelial cells 
Infectious mononucleosis, Burkitt's 
lymphoma, CNS lymphoma in AIDS patients, 
post-transplant lymphoproliferative 
syndrome (PTLD), nasopharyngeal carcinoma, 
HIV-associated hairy leukoplakia 
B cell 
Kaposi's- 
associated 
herpesvirus 
(HHV-8) 
γ 
Lymphocytes, 
other cells 
Kaposi's sarcoma, primary effusion lymphoma, 
some types of multicentric Castleman's disease 
B cell 
*Source https://en.wikipedia.org/wiki/Herpesviridae on 28-Aug 2017 
1.5. 
Rationale for the Combination of HDAC Inhibitors and Antivirals for the 
Treatment of EBV-Associated Lymphomas 
Induction of EBV TK within EBV+ lymphomas is predicted to result in sensitization of these 
tumor cells to antiviral agents such as ganciclovir.10 This approach is predicted to have high 
tumor specificity based on targeting of EBV-containing cells. Support for this approach was first 
demonstrated in a patient with an EBV-associated immunoblastic lymphoma in a donor lung 
4 months following transplantation.11 Based on work demonstrating that butyrate congeners 
could induce EBV lytic phase genes, including viral TK,12,13 a cell line derived from the patient’s 
tumor was exposed to arginine butyrate resulting in induction of EBV TK transcription. 
The combination of arginine butyrate and ganciclovir resulted in inhibition of cell proliferation 
and cell death.11 Arginine butyrate was added to the patient’s existing treatment with ganciclovir 
with no apparent increase in toxicity. Though the patient succumbed to a systemic aspergillus 

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infection that had preceded the administration of arginine butyrate therapy, pathologic 
examination of the tumor demonstrated substantial necrosis compared to pre-therapy histology. 
A definitive causal relationship could not be established based on prior treatment with 
chemotherapy. 
Several histone deacetylase (HDAC) inhibitors in addition to arginine butyrate can induce 
expression of EBV lytic phase genes in vitro, leading to the sensitization of EBV+ lymphoma 
cells to nucleoside antivirals.10,11 These HDAC inhibitors include the short-chain fatty 
acids sodium butyrate and valproic acid, the hydroxamic acids oxamflatin, panobinostat, 
and belinostat, the benzamide entinostat, the cyclic tetrapeptide apcidin, and the macrocyclic 
depsipeptide largazole. In addition, the investigational compound VRx-3996, a hydroxamic acid, 
has also been shown to induce EBV lytic phase genes expression, including TK, in vitro. 
Ongoing studies are evaluating the ability of VRx-3996 to sensitize EBV+ lymphoma cells to 
ganciclovir in vivo. 
Evidence from clinical studies supporting the use of an HDAC inhibitor to sensitize EBV+ tumor 
cells to nucleoside antivirals was demonstrated in a Phase 1/2 study of arginine butyrate 
combined with ganciclovir in 15 patients with EBV+ tumors previously treated with 
chemotherapy and/or radiation.14 Arginine butyrate was administered by continuous intravenous 
(IV) infusion daily on an escalating dose schedule within each patient for 21 days of a 28-day 
treatment course, combined with a fixed dose of daily ganciclovir continuously. Eleven patients 
received at least 28 days of arginine butyrate and ganciclovir, and all 15 patients were evaluable 
for response. Significant antitumor activity was seen in 10 patients, with 4 complete responses 
(CRs) and 6 partial responses (PRs). Three of the patients demonstrating complete clinical 
responses died shortly after completing therapy due to comorbid conditions and complications 
of tumor lysis. On pathological examination, there was complete disappearance of tumor in 
2 patients, and the third had significant necrosis of the residual tumor. 
1.6. 
HDAC Enzymes 
Currently, 18 HDAC enzymes have been identified in mammalian cells, varying in function, 
localization, and substrates as illustrated in Table 2.15,16 Class III enzymes appear relevant to 
certain human diseases but are not implicated in cancer. 
Table 2: 
HDAC Enzymes16 
Class 
HDAC Enzymes 
Zn2+ Dependent 
Localization 
Expression 
I 
1, 2, 3, 8 
Yes 
Nucleus 
Ubiquitous 
IIa 
4, 5, 7, 9 
Yes 
Nucleus and Cytoplasm 
Tissue specific 
IIb 
6, 10 
Yes 
Cytoplasm 
Tissue specific 
III 
Sirtuins 1-7 
No 
Variable 
Variable 
IV 
11 
Yes 
Nucleus and cytoplasm 
Ubiquitous 
1.7. 
HDAC Inhibitors 
Epigenetic modulation of gene expression is an essential biological process, with chromatin 
structure and gene transcription tightly regulated by the acetylation state of histones within the 
nucleosome.15,16 The degree of histone acetylation is a balance between the actions of histone 
acetyltransferases and HDACs. In general, acetylation of histones is associated with induction 

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of gene transcription and deacetylation with decreases in gene transcription. However, HDAC 
inhibition can also have effects on many processes independent of chromatin structure. In tumor 
cells, the most commonly reported effects of HDAC inhibitors relate to induction of apoptosis, 
though they have also been shown to interfere with cell growth and differentiation and inhibit 
angiogenesis. In addition, HDAC inhibitors have been shown to modulate immune responses 
which, in turn, affect many diverse cellular functions. 
To date, at least 15 HDAC inhibitors have been tested in preclinical and clinical studies. These 
HDAC inhibitors are broadly classified into 4 main groups based on their structure as illustrated 
in Table 3. The common mechanism of action of these drugs is to bind a critical Zn2+ ion 
required for catalytic function of the HDAC enzyme. 
Four HDAC inhibitors are currently approved by the United States (US) Food and Drug 
Administration (FDA) for oncology indications. These are: 
• Vorinostat (2006) for the treatment of cutaneous T-cell lymphoma, 
• Romidepsin (2009) for the treatment of cutaneous T-cell lymphoma, 
• Belinostat (2014) for the treatment of peripheral T-cell lymphoma, and 
• Panobinostat (2015) for the treatment of multiple myeloma. 
Common side effects seen with HDAC inhibitors include thrombocytopenia, neutropenia, 
anemia, fatigue, and diarrhea. While HDAC inhibitors have displayed antitumor activity as 
single agents, data suggest that the HDAC inhibitors may have a greater role as part of 
combination regimens.16,17 
Table 3: 
Selected HDAC Inhibitors in Clinical Use or Development* 
Class 
Class members 
HDAC Class Specificity 
Hydroxamic acid 
VRx-3996 (CHR-3996) 
Vorinostat (SAHA, Zolinza®) 
Belinostat (PXD101, Beleodaq®) 
Panobinostat (LBH589, Farydak®) 
I 
I, II, IV 
I, II, IV 
I, II, IV 
Cyclic peptides/ depsipeptides 
Romidepsin (Istodax®) 
I 
Benzamide 
Entinostat (SNDX-275/MS-275) 
Mocetinostat (MGCD0103) 
I 
I 
Short-chain fatty acids 
Valproic acid 
Butyrate 
I, IIa 
I, IIa 
*Adapted from Lane et al.16 
1.8. 
VRx-3996 (nanatinostat) 
VRx-3996 (formerly CHR-3996) is a selective HDAC Class I inhibitor with activity against 
HDAC1, HDAC2, and HDAC3. In both tumor cell lines and tumor xenograft models, VRx-3996 
inhibited growth across a wide spectrum of human tumor types and demonstrated synergistic 
activity in combination with agents such as erlotinib, decitabine, and tosedostat.18 
A Phase 1 study of VRx-3996 as a single-agent was performed in 39 patients with refractory 
solid tumors.19 The study included 26 men and 13 women with a mean age of 56 years 
(range 24–77). Most patients had an Eastern Cooperative Oncology Group (ECOG) performance 

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status (PS) of 0 or 1 (1 patient was PS 2). All patients had received prior treatment with a median 
number of prior systemic chemotherapy regimens of 2 (range 0–7). 
VRx-3996 was administered once daily (QD) orally at doses ranging from 5 to 160 mg on 
a 28-day cycle. The median number of completed cycles was 2 (range 1-18), with 12 patients 
receiving 3 or more cycles. 
Dose-limiting toxicities (DLTs) were thrombocytopenia (160 mg), fatigue (80 and 120 mg), 
elevations in serum creatinine (80 and 120 mg), and atrial fibrillation (40 mg). The maximum 
tolerated dose (MTD) for QD continuous dosing of VRx-3996 was established as 80 mg. 
Most adverse events (AEs) were low grade (Grade 1 or 2), though Grade 3 or 4 events were seen 
in 27 patients. The most prevalent AEs were fatigue and nausea. Incidences of nausea, 
thrombocytopenia, and increased creatinine appeared to be dose related, while fatigue appeared 
unassociated with dose. 
Of the 39 patients receiving at least 1 dose of VRx-3996, 1 patient (2.5%) in the 160 mg dose 
group had a PR and continued study treatment for 12 months. An additional 9 patients (23%) had 
stable disease (SD). 
The pharmacokinetics (PK) of VRx-3996 demonstrated rapid absorption with a median time to 
maximum concentration (Tmax) of 1 hour (range 1–4 hours). The maximum concentration (Cmax) 
achieved ranged from 18.5 ng/mL at 5 mg to 774.3 ng/mL at 160 mg. The median terminal 
elimination half-life (t½) for was 1.8 hours (range 1.1–7.8 hours). 
Exposure to VRx-3996 (area under the curve [AUC]) was broadly proportional over the dose 
range tested. At 40 mg daily, plasma concentrations exceeded 10 ng/mL for approximately 
8 hours, a concentration associated with antitumor efficacy in preclinical models. There was no 
apparent accumulation between Day 1 and 28. The use of proton pump inhibitors did not appear 
to reduce absorption. 
Table 4: 
PK Parameters of VRx-3996 
Dose 
(mg/day) 
5 
10 
20 
40 
80 
120 
160 
Number of 
patients 
3 
4 
3 
10 
10 
4 
5 
Mean Cmax 
ng/mL 
(CV%) 
18 
(121) 
34 
(91) 
54 
(68) 
259 
(100) 
359 
(167) 
340 
(114) 
774 (74) 
Median 
Tmax h 
(range) 
4 (2–
4) 
1 
(0.3–
4) 
4 
(0.3–
4) 
1 
(0.3–
4) 
1 
(0.3–
4) 
1 (1–
2) 
1 (0.3–4) 
Mean 
AUC0-∞ 
ng×h/mL 
(CV) 
* 
111 
(57) 
93# 
630 
(74) 
1214 
(138) 
888 
(103) 
1985 (66) 
Abbreviations: AUC0-∞ = area under the concentration-time curve from administration to infinity; Cmax = maximum 
concentration; Tmax = time to maximum concentration. 
* No reliable estimate of terminal elimination rate constant for this cohort. 
# Only one reliable observation. 

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The pharmacodynamic effect of VRx-3996 was evaluated by acetylation of histone H3 in 
peripheral blood mononuclear cells (PBMCs). Samples were collected on Days 1 and 28 of the 
first course of therapy, and values normalized to pretreatment levels. Increased histone 
acetylation was apparent 4 hours after drug administration and returned towards baseline by 
24 hours. Increases in histone acetylation were first seen at 20 mg per day and appeared to 
plateau at 40 mg per day. 
1.9. 
Valganciclovir 
Valganciclovir (VALCYTE®), an oral prodrug of ganciclovir, is approved for treatment 
of CMV retinitis in patients with AIDS and prevention of CMV disease in high-risk transplant 
patients. Outside of its approved indications, valganciclovir has been shown to be effective in 
mitigating EBV viral load in EBV+ pediatric liver transplant patients at risk for development 
of post-transplant proliferative disorder.20 Recommended adult dosing for treatment of CMV 
retinitis is 900 mg orally twice daily (BID) for 21 days followed by a maintenance dose of 
900 mg once a day. 
Oral valganciclovir is well absorbed (~60%) and converted to ganciclovir by first-pass intestinal 
or hepatic metabolism with peak plasma concentrations achieved in 1 to 3 hours. The major 
elimination pathway is renal excretion of ganciclovir through glomerular filtration and active 
tubular secretion. Dosage reductions, based on creatinine clearance, are recommended for 
patients with renal impairment. The antiviral activity of valganciclovir is based on the generation 
of ganciclovir-triphosphate, which is a competitive substrate for the CMV DNA polymerase. 
Significant AEs include hematologic toxicity and acute renal failure. Hematologic toxicity may 
result in leukopenia, neutropenia, anemia, and thrombocytopenia. The VALCYTE® package 
insert includes guidance regarding pre-treatment hematologic assessment and complete blood 
count (CBC) monitoring. Elderly patients, patients receiving nephrotoxic drugs and inadequately 
hydrated patients are at higher risk for renal failure. Other common AEs include gastrointestinal 
manifestations, such as diarrhea, nausea, and vomiting. 
1.10. Rationale for Starting Dose 
The dose for valganciclovir will follow the approved dose as described in the label or a modified 
dose based on agreement between the Investigator and the Medical Monitor to manage known 
valganciclovir-associated AEs. The safety profile for this dose of valganciclovir is well defined 
and appears acceptable as part of a treatment regimen for patients with relapsed/refractory 
lymphoma. 
The starting dose for VRx-3996 (20 mg per day) is 25% of the MTD determined in a prior 
clinical study of VRx-3996 and 50% of the recommended Phase 2 dose (RP2D) from the same 
study. While overlapping toxicities exist (e.g., renal dysfunction and thrombocytopenia), the 
reduced dose of VRx-3996 and close monitoring of patients during the study should provide for 
acceptable safety. 
1.11. Rationale for Study 
VRx-3996 in combination with valganciclovir appears appropriate for evaluation in humans 
based on the following: 

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• EBV-associated lymphomas are often aggressive malignancies that respond poorly to 
conventional treatments 
• VRx-3996 has been administered previously to patients with advanced solid tumors 
and demonstrated acceptable safety but limited anti-tumor activity 
• Valganciclovir is an approved antiviral medication with a well understood safety profile 
at its approved dose and schedule (i.e., 900 mg PO BID) 
• Clinical proof of concept exists for the combination of an HDAC inhibitor (i.e., arginine 
butyrate) and an EBV antiviral (i.e., ganciclovir) in patients with EBV+ lymphomas that 
demonstrated promising antitumor activity with an acceptable safety profile 
• VRx-3996 combined with valganciclovir should demonstrate at least equivalent activity 
and safety compared to arginine butyrate and ganciclovir at the proposed starting doses 
for this study 
1.12. Potential Risks and Benefits 
1.12.1. Potential Risks 
Both VRx-3996 and valganciclovir exhibit overlapping toxicities (i.e., thrombocytopenia 
and renal dysfunction) that may be increased in rate or severity with this combination. 
In addition, in prior clinical studies other toxicities reported for one or both agents include 
fatigue, atrial fibrillation, nausea/vomiting, anemia, leukopenia, and neutropenia. 
While not all have been reported for VRx-3996, toxicities reported for other HDAC inhibitors 
include, thrombocytopenia, neutropenia, anemia, fatigue and diarrhea.21 
As with any new combination, toxicities, which have not been seen with either agent alone 
or with combinations of similar agents, may become manifest. Similar combinations (arginine 
butyrate combined with ganciclovir)14 have resulted in rapid tumor destruction and loss of tissue 
integrity resulting in death. 
1.12.2. Potential Benefits 
VRx-3996 combined with valganciclovir may benefit patients by reducing lymphoma volume 
and/or slowing lymphoma growth. Patients who experience a CR following administration 
of VRx-3996 and valganciclovir could experience substantial benefit. In patients with symptoms 
related to the presence of lymphoma, VRx-3996 and valganciclovir may result in a reduction 
of symptoms. 
2. 
OBJECTIVES 
2.1. 
Primary Objective 
• Determine the safety and tolerability of VRx-3996/valganciclovir 
• Determine a RP2D of VRx-3996/valganciclovir 
• Assess activity based on overall response rate (ORR) 

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2.2. 
Secondary Objectives 
• Evaluate PK parameters of varying doses of VRx-3996 in capsule form and in tablet form 
(at RP2D only for tablet form) 
• Evaluate PK parameters of varying doses of valganciclovir 
• Evaluate time to response (TTR) 
• Evaluate duration of response (DoR) 
• Determine progression-free survival (PFS) and overall survival (OS) 
2.3. 
Exploratory Objectives 
• Evaluate changes in viral loads (CMV, EBV) by qPCR with treatment, where applicable 
• Evaluate EBV latency/lytic profile 
• Evaluate changes in histone acetylation in PBMCs 
• Evaluate immunophenotype and immune function in PBMCs 
3. 
STUDY DESIGN 
This is an open-label, 2-part (Phase 1b = dose escalation, Phase 2 = dose expansion) Phase 1b/2 
study of VRx-3996 and valganciclovir. The Phase 1b portion of the study will evaluate safety 
and define a recommended Phase 2 dose (RP2D) using a modified 3+3 design for oncology 
studies in patients with EBV+ lymphomas. The Phase 2 portion of the study will evaluate the 
RP2D in 30 patients with EBV-associated lymphomas or lymphoproliferative disease, using a 
Simon’s 2-stage design to allow for early stopping for futility. The study defines a cycle length 
as 28 days. Valganciclovir will be administered at no higher than the approved dose of 900 mg 
PO BID. 
During the Phase 1b portion of the study, dosing will be based on assigned cohort. During the 
Phase 2 expansion portion, patients will receive the RP2D of VRx-3996 defined previously in 
the Phase 1b portion of the study. In both phases, patients will continue to receive VRx-3996/ 
valganciclovir if they may still have clinical benefit in the opinion of the Investigator, and in the 
absence of unacceptable toxicity.  
Safety assessments will make use of all available data including using vital signs, physical 
exams, electrocardiograms (ECGs), PS assessments, and clinical laboratory parameters. 
Response assessments will be performed using imaging modalities appropriate for the patients’ 
specific lymphoma (e.g., positron emission tomography [PET]-computed tomography (CT), 
CT scans, magnetic resonance imaging [MRI]) based on the Recommendations for Initial 
Evaluation, Staging, and Response Assessment of Hodgkin and Non-Hodgkin Lymphoma: 
the Lugano Classification.22 
Patients considered at risk for tumor lysis syndrome will receive prophylactic medications 
and interventions. 

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3.1. 
Phase 1b (Dose Escalation) 
3.1.1. Cohort Size 
Cohort size during the Phase 1b portion of the study will be up to 7 patients using a conventional 
modified 3+3 design for dose escalation studies in oncology. The first cycle (28 days) is defined 
as the DLT assessment period. At each dose level, 3 or 4 patients will initially be enrolled 
and followed through the DLT assessment period. If 1 patient in the initial 3 or 4 patients 
experiences a DLT, the cohort will be expanded to 6 or 7 total patients. 
3.1.2. Cohort Enrollment 
Enrollment will begin with the Phase 1b portion of the study at the starting cohort as indicated in 
Table 5. 
In the interest of safety, the patient enrollment rate will be limited to no more than 1 patient 
per week in the starting cohort. The enrollment rate in subsequent cohorts will not be limited. 
A patient who experiences clinical benefit while on study treatment, and then experiences 
progressive disease while not receiving VRx-3996/valganciclovir, may have study drugs 
restarted if the following conditions are met: 
• Restarting study drugs is considered in the patient’s best interest by the Investigator, 
• The patient has not developed any contraindications to either study drug, 
• The Investigator has discussed restarting study drugs with the study Medical Monitor 
who agrees that restarting of study drugs is appropriate, and 
• The study has not been closed by the Sponsor. 
The patient should restart study drugs at the RP2D if this dose is tolerated. 
3.1.3. Cohort Doses and Regimens 
During the Phase 1b portion of the study, the doses of VRx-3996 and valganciclovir will follow 
those outlined in Table 5. On Cycle 1 Day 1, in an effort to ensure that patients tolerate oral 
valganciclovir prior to receiving VRx-3996, valganciclovir will be taken first, followed by 
VRx-3996 approximately 1 hour later. For all subsequent administrations, the sequence of 
VRx-3996 and valganciclovir can be dictated by patient convenience (e.g., both drugs may be 
taken together if tolerated by the patient). With the implementation of Protocol Amendment 4.0, 
VRx-3996 and valganciclovir are taken together at all timepoints, including Cycle 1 Day 1. 
The Safety Review Committee (SRC) (Section 3.10) will have the option of defining additional 
cohorts and doses either below, above, or intermediate to the doses listed in Table 5 as needed 
based on data generated from prior cohorts. The SRC may also define additional cohorts based 
on alternative dosing schedules (e.g., QD versus BID). 

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Table 5: 
Phase 1b Cohort Doses 
Cohort Number 
Dose VRx-3996** 
Dose valganciclovir** 
1 
10 mg BID (20 mg daily dose) 
900 mg BID 
2a 
5 mg BID (10 mg daily dose) 
450 mg BID 
2b 
10 mg QD (10 mg daily dose) 
450 mg BID 
2c 
10 mg QD (10 mg daily dose) 
900 mg QD 
3 
20 mg QD (20 mg daily dose) # 
900 mg QD 
Abbreviations: BID = bis in die (twice daily; PO = per os (oral); QD = quaque die (once daily); SRC = Safety Review 
Committee 
** The Schedule used (e.g., QD, BID) for either VRx-3996 or valganciclovir may be modified by the SRC as required to 
accommodate different dosage strengths and patient convenience. However, when the schedule is adjusted, the total daily 
dose will remain unchanged. 
#  In Cohort 3, VRx-3996 will be administered PO QD for 4 days on and 3 days off in a 7-day regimen. The dosing holiday is 
not considered a dosing hold; if a dose is held for any length of time beyond the 3-day dosing holiday (e.g., dosing does not 
resume on Cycle 1 Day 8), those subsequent days will constitute a dose hold. Please refer to Section 3.5 Dose 
Adjustments/Modifications/Delays. If the next dose of VRx-3996 following a dosing holiday (e.g., Cycle 1 Day 8) does not 
coincide with a scheduled visit, the patient should take the next scheduled dose at home. 
3.1.4. Dose Escalation Procedure 
Dose escalation during the Phase 1b portion of the study will follow commonly accepted criteria 
used in a modified 3+3 Phase 1 study design. 
Dose levels of VRx-3996 and valganciclovir in sequential cohorts will be defined prior to the 
start of each cohort. If the MTD is exceeded, de-escalation may occur to a lower dose level. Each 
cohort will initially consist of 3 to 4 patients (See Section 3.1.1).  
If none of the first 3 or 4 patients in a cohort demonstrates a DLT during the first cycle (28 days), 
then the cohort will be declared safe and the next higher cohort will be opened for enrollment.  
If 1 of the first 3 or 4 patients in a cohort demonstrates a DLT during the first cycle (28 days), 
then an additional 2 or 3 patients will be enrolled to that cohort for a total of 6 patients.  
If 1 out of 6 patients in an expanded cohort demonstrates a DLT during the first cycle (28 days), 
then the cohort will be declared safe and the next cohort will be opened for enrollment.  
If 2 or more patients in an expanded cohort demonstrate a DLT, that cohort will be declared to 
exceed the MTD. 
The MTD (if reached) will be defined as the highest dose level at which no more than 1 of 
6 patients demonstrates a DLT. 
If the MTD is exceeded, then the next lowest dose cohort, or an intermediate dose level 
(as determined by the SRC) will be expanded to at least 6 patients. 
3.1.5. Dose Limiting Toxicity 
Grading of DLTs will be according to the National Cancer Institute Common Terminology 
Criteria for Adverse Events (NCI CTCAE) version 5. 
To be considered a DLT, an AE must meet all of the following criteria: 

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• Occurs during the first cycle (28 days) of study drug administration in Phase 1b only 
• Is not incontrovertibly related to underlying disease 
In addition, to be considered a DLT, the AE will meet at least one of the criteria listed below: 
• Grade 4 anemia unexplained by underlying disease 
• Grade 4 febrile neutropenia 
• Grade 4 neutropenia lasting >5 days 
• Any other Grade 4 hematologic toxicity of any duration 
• Grade 4 or higher tumor lysis syndrome 
• Grade 3 or higher thrombocytopenia (with or without bleeding) 
• Any requirement for platelet transfusion 
• Grade 3 or higher non-hematologic toxicity despite adequate supportive care 
• Results in a dose hold of >7 consecutive days 
Adverse events may be excluded from the definition of DLT if they meet the following criterion: 
• AEs that persist <72 hours and are able to be managed with supportive care 
The SRC (Section 3.10) will have the option of declaring other toxicities, not listed above, as 
DLTs if necessary to ensure patient safety. 
3.1.6. Continued Study Drugs Following DLT 
In the Phase 1b portion of the study, patients experiencing a DLT will not receive additional 
study drugs unless all the following conditions are met: 
• The DLT has returned to at least Grade 2 or clinically insignificant from baseline 
• The DLT is not expected, in the opinion of the Investigator, Medical Monitor 
and Sponsor representative, to recur based on an intervention such as prophylactic use of 
appropriate treatment (e.g., prophylactic anti-emetics), or dose reduction from the prior 
dose 
• Continued administration of study drugs is considered to be in the patient’s best interest 
based on the opinion of the Investigator and the study Sponsor 
3.1.7. Maximum Tolerated Dose 
While this study is not designed to define a MTD for this combination of study drugs, in the 
event that a DLT is observed, the MTD of VRx-3996 with valganciclovir will be defined as the 
highest dose administered during Cycle 1 of Phase 1b at which no more than 33% (i.e., ≤1 of 6 
or 7 patients) experiences a DLT. 
3.1.8. Dose Increases for Individual Patients 
In an effort to afford patients the greatest likelihood of benefit from study participation, if judged 
to be in the best interest of the patient by the Investigator, Medical Monitor, and Sponsor 
representative, patients may receive an escalated dose of VRx-3996 in subsequent cycles. This 
escalated dose will generally follow the dose levels previously explored in the study and may not 
exceed the highest dose shown to be safe (i.e., the highest dose that has been demonstrated not to 
exceed the MTD based on evaluation of at least 3 patients at that level). In addition, no patient 

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may undergo a dose escalation until having completed at least 2 cycles at their initial assigned 
dose. 
3.1.9. Replacement of Patients during Phase 1b Portion of Study 
Patients who are unable to complete the DLT assessment period for reasons other than study 
drug related toxicity may be replaced if needed to achieve at least 3 patients evaluable for DLTs. 
The final decision on replacement will rest with the SRC. 
In the event that a cohort is filled with 4 patients, and if 1 of the 4 patients is considered not 
evaluable for safety or for reasons other than study drug related toxicity, this 4th patient will not 
be replaced, and a decision will be made by the SRC on the safety of the current cohort based on 
the remaining 3 patients. 
3.2. 
Phase 2 (Dose Expansion) 
3.2.1. Phase 2 Sample Size 
The Phase 2 portion of the study will accrue 30 patients. Any patients in screening at the time 
that the 30th patient is enrolled will be permitted to enroll, should they be eligible. This sample 
size is based on a Simon’s 2-stage design where the Phase 2 portion of the study may be stopped 
if none of the first 10 treated patients have a response. The hypothesized response rate of a poor 
drug is 5%, while the hypothesized response rate of a good drug would be at least 20%. Using a 
1-sided alpha of 0.05 and power of 80%, if at least 1 of the first 10 patients has a response, the 
Simon’s design recommends accruing up to at least 29 total subjects to test the null hypothesis. 
The probability of stopping early is 59.9% with a type I error rate of 0.0468 
(http://cancer.unc.edu/biostatistics/program/ivanova/SimonsTwoStageDesign.aspx). 
3.2.2. Phase 2 Dose 
The dose and schedule of VRx-3996 and valganciclovir used during the Phase 2 portion of the 
study will be the RP2D for VRx-3996 and valganciclovir as determined by the SRC at the 
conclusion of the Phase 1b portion of the study. 
Based on accumulating efficacy and safety data, the SRC may elect to declare a RP2D prior to 
defining an MTD or prior to exploring all cohorts listed in Table 5. 
The RP2D may be modified later during the Phase 2 portion of the study by the SRC (see 
Section 3.2.3 and Section 3.10) if information arises suggesting that the initial RP2D was not 
appropriate. In the event that the RP2D is adjusted mid-study, all subsequent patients entering 
the study will receive study drugs at the adjusted RP2D. Patients currently on study at the time 
of a dose modification may continue with their current dose at the discretion of the Investigator. 
3.2.3. Assessment of Toxicity During Phase 2 Dose Expansion 
Sequential boundaries will be used to monitor the DLT rate during the dose expansion phase of 
the study.29 If an excessive number of DLTs are seen, the SRC will have the option of either 
halting study accrual or reducing the RP2D to reduce the level of toxicity. The boundaries at 
which the study is halted or the RP2D is reduced are listed in Table 6. This is a Pocock-type 

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boundary that yields at most a 5% probability of crossing the boundary when the rate of DLT is 
equal to the acceptable rate of 30%. 
Table 6: 
Early Stopping Boundaries for Toxicity 
 # Patients 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
Boundary 
- 
- 
- 
4 
5 
5 
6 
6 
7 
7 
8 
8 
9 
9 
9 
 # Patients 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
Boundary 
10 
10 
11 
11 
12 
12 
12 
13 
13 
14 
14 
14 
15 
15 
15 
 
3.2.4. Phase 2 Study Drug(s) Administration Schedule 
 
 
 
In the Phase 2 portion of the study VRx-3996 will be administered 20 mg PO QD for 4 days 
on and 3 days off in a 7-day regimen. Valganciclovir will be administered 900 mg PO QD. 
VRx-3996 and valganciclovir will be taken at the same time for all visits. 
The administration schedule used for VRx-3996 and/or valganciclovir may be modified as 
appropriate by the SRC during the course of the study. Changes to the schedule will be enacted 
with minimal or no change in the total daily dose. 
If employed during the study, the following schedule definitions will be used: 
• QD – Once each day at approximately the same time 
• Q12 hours – Twice each day at between a 10 to 14-hour interval 
• BID – Twice each day at between 8- and 12-hour intervals (preferably at 12-hour 
intervals when possible) 
The SRC may define and employ other schedules as appropriate based on data accumulated 
during the course of the study. 
3.3. 
Tablet Cohort  
Once the Phase 2 arm has completed enrollment, approximately 10 patients will be enrolled into 
a cohort to receive VRx-3996 tablets instead of capsules. Approximately 10 patients will be 
needed to provide an assessment of systemic exposures to VRx-3996. The dose and schedule of 
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(VRx-3996 20 mg PO QD for 4 days on and 3 days off in a 7-day regimen with valganciclovir 
900 mg PO QD starting at C1D1). VRx-3996 and valganciclovir will be taken at the same time 
for all visits.   
The intent of these evaluations will be important to the clinical development program for 
assessing comparability of exposures to VRx-3996 administered as a tablet presentation, for 
comparison to delivery of the oral capsule product. The tablet form of VRx-3996 allows for a 
reduction from four 5 mg capsules to two 10 mg VRx-3996 tablets per dose on a daily basis and 
is expected to be less of a burden for patients. 
With exceptions as described in the protocol, patients will follow the protocol/assessments as 
detailed for the Phase 2 expansion cohort patients. 
3.4. 
Continuation of VRx-3996/Valganciclovir 
Patients may continue to receive VRx-3996/valganciclovir provided the following criteria are 
met: 
• Patient does not demonstrate progressive disease (in the absence of clinical deterioration, 
patients may continue on study drug until a repeat scan confirms progression)   
• Patient has not experienced unacceptable toxicity that cannot be resolved with supportive 
treatment, a dose reduction, or interruption 
• The Investigator considers additional VRx-3996/valganciclovir to be in the best interest 
of the patient 
3.5. 
Dose Adjustments/Modifications/Delays 
Details on dose adjustments, modifications, and delays are outlined in Section 5.1.8 
and Section 5.2.5.  
Patients who have had a dose hold should continue to follow all assessments called for in the 
Schedule of Events (i.e., if a patient undergoes a dose interruption, this will not delay conduct 
of any study procedures). 
3.6. 
Central Pathology Review 
A central review of pathology may be performed on available (archived or fresh) tumor samples 
taken from patients. This will include any historical diagnostic samples and samples available at 
the time of study entry in addition to samples taken per standard of care during study 
participation and samples taken at the time of relapse. Archived samples will be used to further 
characterize the tumor. Presence of EBV for eligibility will be determined by either a local 
or central pathology lab. Patients enrolled on the basis of a local result will have repeat testing at 
a central laboratory. The process for submitting archived tissue and procedures for central 
pathology review will be covered in a separate Study Manual. 
3.7. 
Laboratory Procedures 
Sites may elect to use either central or local laboratory tests for purposes of eligibility, safety, 
and other study required tests. The central laboratory kits should be utilized for the 
protocol-specified exploratory tests.  

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Any local labs collected for eligibility, or required by the study protocol, or to make treatment 
decisions will be entered into the electronic case report forms (eCRF). 
The process for submitting central laboratory samples will be covered in the Laboratory Manual. 
3.8. 
Central Radiology Review 
Central review of patient scans (CT, MRI, PET-CT) will be performed by the Sponsor. 
A de-identified digital copy of each scan accompanied by the local radiology report will be 
generated by the site and sent to the Sponsor for review. The specific scan format and method 
of transfer will be arranged with each site. The review performed centrally may include 
an assessment based on both the Lugano23 and RECIL23 criteria. 
3.9. 
Central ECG Review 
Central review of patient ECGs will be performed by the Sponsor. A de-identified copy of each 
scan will sent to the Sponsor for review. The specific format and method of transfer will be 
arranged with each site. The Sponsor may elect to review all ECGs or a subset. 
3.10. Safety Review Committee (SRC) 
An SRC will govern the conduct of the study. The SRC will consist of the following individuals 
appointed by the Sponsor: 
• Study Investigators 
• The Study Medical Monitor 
• A Sponsor representative 
Responsibilities of the SRC will include: 
• Reviewing study safety data throughout conduct of the study 
• Confirming or modifying the specific dose escalations between cohorts 
• Defining intermediate dose levels as appropriate 
• Declaring the MTD (if reached) 
• Determining the RP2D 
• Providing guidance on treatment-related issues raised by an Investigator 
The SRC will meet at the end of each cohort during the Phase 1b portion and approximately 
quarterly during the Phase 2 portion, or as needed based on the rate of enrollment. 
A Core SRC consisting of 2 investigators and 1 clinical expert appointed by the Sponsor will 
assess the toxicity during Phase 2 dose expansion (Section 3.2.3). 
3.11. Concomitant Medications, Treatments, and Procedures 
Drug-interaction studies with VRx-3996 have not been conducted. During their participation on 
this study, patients may continue to use concomitant mediations, treatments, and procedures 
previously prescribed to treat non-cancer related conditions provided that, in the Investigator’s 
judgment, they will not interfere with the study outcomes. Concomitant medications will be 
documented until 28 days following the last dose of study drug, or until a new anti-cancer 
therapy is started if sooner than 28 days. 

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3.11.1. Cytochrome P450 Substrates 
A study with recombinant human cytochrome P450 isoforms (CYP450) suggests that VRx-3996 
is a direct inhibitor of CYP3A4 isoform. In vitro studies indicated that VRx-3996 is not 
metabolized by or induces the activity of CYP3A4. A potential for drug interactions between 
VRx-3996 and drugs that are substrates of CYP3A4 is low but cannot be ruled out (see 
Table 18a in the Appendix). Please refer to the Investigator Brochure for detailed description. 
3.11.2. Transporter Substrates and Inhibitors 
Transporter studies indicate VRx-3996 is likely a substrate of MDR1 and BCRP transporters, 
but not an inhibitor of these transporters. Therefore, the protocol should limit or restrict strong 
MDR1/P-gp and BCRP inhibitors relevant to the patient population when administered with 
VRx-3996 (see Table 18b in the Appendix). 
The effect of gastric pH on study drug absorption is not known. Unless necessary for patient 
care, proton pump inhibitors and H2 antagonists should be avoided, and antacids should not be 
given in the 2 hours prior to or within 4 hours post VRx-3996 administration. 
3.12. Prophylactic Medications, Treatments, and Procedures 
With the exception of prophylactic medications intended to reduce the risk of Tumor Lysis 
Syndrome (TLS) in patients at risk for TLS, the use of prophylactic medications intended to 
reduce toxicity associated with VRx-3996/valganciclovir will not initially be allowed. 
The SRC may elect to institute the use of prophylactic medications (e.g., for prevention of 
nausea and vomiting secondary to study drugs) during the study. The specific medications used 
will be in keeping with generally accepted standards of care and the institutional guidelines of 
the participating sites. 
Prophylaxis for Tumor Lysis Syndrome (TLS) 
Patients considered to be at risk for TLS based on specific characteristics (e.g., specific 
diagnosis, renal insufficiency, bulky disease, elevated lactate dehydrogenase [LDH]) should 
receive TLS prophylaxis.24 
The determination of a patient’s risk for TLS can be estimated based on Table 7. 
Table 7:  
Patient Stratification by Risk (adapted from Coiffier 2008)24 
Type of Cancer 
High risk 
Intermediate risk 
Low risk 
NHL 
Burkitt’s, lymphoblastic, 
B-ALL 
DLBCL 
Indolent NHL 
ALL 
WBC ≥100,000 
WBC 50,000–100,000 
WBC ≤50,000 
CLL 
 
WBC 10,000–100,000 
WBC ≤10,000 
Abbreviations: ALL = acute lymphoblastic leukemia; B-ALL = Burkitt’s acute lymphoblastic leukemia; CLL = chronic 
lymphocytic leukemia; DLBCL = diffuse large B-cell lymphoma; NHL = non-Hodgkin’s lymphoma. 
 

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Patients considered at high risk for TLS should be managed in the inpatient setting with 
increased laboratory monitoring during the first 48 hours. Patients should receive rasburicase 
based on the recommended dosing outlined in Table 8. 
Table 8:  
Recommended Rasburicase Dosing (adapted from Coiffier 2008)24 
Risk profile 
Baseline uric acid 
Dose 
(mg/kg)* 
Duration 
mg/dL 
mmol/L 
High 
>7.5 
>450 
0.20 
Based on plasma uric acid levels 
Intermediate 
<7.5 
<450 
0.15 
Based on plasma uric acid levels 
Low 
<7.5 
<450 
0.10 
Clinical judgement 
* Sites may choose to follow institutional standards for dosing rasburicase if they differ from those outlined in Table 8. 
 
Patients should also receive hydration with fluid intake maintained at approximately 1 to 2 times 
maintenance, with a urine output of 80 to 100 mL/m2/hour.24 
3.13. Rescue Medications, Treatments, and Procedures 
The Investigator will determine the appropriateness and use of any medications, treatments, 
or procedures required to adequately treat study-related toxicities or complications 
(e.g., treatment of drug-induced nausea or vomiting, treatment of myelosuppression or anemia). 
Any rescue medication, treatments, or procedures will be consistent with accepted medical 
practice and institutional guidelines. 
3.14. Prohibited Cancer Treatments 
The following medications/therapies intended to treat the patients’ underlying cancer are 
prohibited during the study 
• Other investigational agents 
• Other cancer therapies other than those which the patient has received for at least 
6 months and which the Investigator, Medical Monitor, and Sponsor representative agree 
are unlikely to interfere with the study objectives (e.g., hormonal therapy for prostate 
cancer) 
3.15. Discontinuation of VRx-3996/Valganciclovir 
VRx-3996/valganciclovir may be discontinued in the event of any of the following: 
• Clinically significant progressive disease (sites may elect to allow patients to continue 
study drug administration and confirm progressive disease with a follow-up evaluation to 
rule out pseudoprogression as outlined in the RECIL criteria)23 
• Unacceptable AE(s) considered secondary to VRx-3996/valganciclovir despite 
appropriate therapy 
• Withdrawal of consent for study drug administration by the patient (patient may agree to 
continue to be followed for safety and survival) 
• Noncompliance by the patient at the discretion of the Investigator and Medical Monitor 
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• Termination of study by the Sponsor 
If the patient withdraws consent for treatment, it is important to continue to collect follow-up 
data, if possible. The Investigator must discuss this option with the patient. 
3.16. Restarting Study Drugs at Relapse 
Patients who experienced clinical benefit while on study treatment, and then experience 
progressive disease while not receiving VRx-3996/valganciclovir, may have study drugs 
restarted if the following conditions are met: 
• Restarting study drugs is considered in the patient’s best interest by the Investigator 
• The patient has not developed any contraindications to either study drug 
• The Investigator has discussed restarting study drugs with the study Medical Monitor 
who agrees that restarting of study drugs is appropriate 
• The study has not been closed by the Sponsor 
Patients will generally restart study drugs at the RP2D; however, the dose and schedule may be 
altered if considered in the best interest of the patient by the Investigator, Medical Monitor, 
and Sponsor representative. 
3.17. Removal of Patients from Study Follow-Up 
No additional follow-up of a patient will occur in the event of any of the following: 
• Request by the patient to no longer be followed (e.g., withdrawal of consent for 
follow-up) 
• Patient is lost to follow-up 
• Termination of study by Sponsor 
3.18. Replacement of Patients During Phase 2 Portion of Study 
Patients who are unable to complete at least 1 disease assessment to evaluate efficacy during the 
Phase 2 portion of the study may be replaced. 
3.19. Handling of Patient Withdrawal or Termination 
Data generated from patients prior to withdrawal from the study will be maintained and utilized 
in the final study analysis. No data generated from patients after their withdrawal from the study 
will be collected. 
3.20. Premature Termination or Suspension of Study 
In the event that the Sponsor elects to terminate or suspend this study prior to completion, the 
Sponsor will discuss the feasibility of continued administration of VRx-3996/valganciclovir with 
each participating Investigator for those patients that appear to be benefitting from 
VRx-3996/valganciclovir. 
The Sponsor will also cooperate with participating sites in terms of collecting outstanding study 
data sufficiently to allow for the generation of a study manuscript. 

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In the interest of avoiding the administration of VRx-3996 to more patients than is reasonable in 
the dose expansion phase of the study, this study will utilize a Simon's 2-stage design.25 See 
Section 3.2.1 for sample size details and stopping rules of the Simon’s 2-stage design. 
4. 
STUDY ELIGIBILITY 
4.1. 
Inclusion Criteria 
1. Signed, informed consent 
2. Age 18 or more years 
3. ECOG PS26 of 0 to 2 or Karnofsky Performance scale (KPS) ≥60% 
4. Failed any available standard therapy with a reasonable likelihood of clinical benefit 
(e.g., anti-CD20 monoclonal antibody, withdrawal of immunosuppression, cytotoxic 
chemotherapy) 
5. Relapsed/refractory, pathologically confirmed EBV+ lymphoid malignancy 
or lymphoproliferative disease regardless of histologic subtype 
6. EBV+ as determined by institution’s usual testing method or by the Sponsor’s central 
laboratory on a specimen that is representative of the current disease (e.g., for patients who 
have relapsed the biopsy specimen should have been taken post-relapse). For questions on 
the suitability of particular specimens, please consult the Medical Monitor 
7. Absence of available therapy with reasonable likelihood of cure or significant clinical benefit 
8. Evaluable [Phase 1b only] or measurable [Phase 1b and Phase 2] disease based on 
Recommendations for Initial Evaluation, Staging, and Response Assessment of Hodgkin 
and Non-Hodgkin Lymphoma: The Lugano Classification22 
9. If previously treated: 
a. Treatment-related toxicity resolved to at least Grade 1 (alopecia excepted), or 
b. Treatment-related toxicity resolved to at least Grade 2 with prior approval of the Medical 
Monitor, or 
c. Treatment related toxicity resolved to at least the levels outlined in inclusion criterion 
#10, without transfusion support. 
10. Adequate laboratory parameters including: 
a. Absolute neutrophil count (ANC) ≥1000/mm3 
b. Platelet (PLT) count ≥50,000/mm3 
c. Hemoglobin ≥8.0 g/dL 
d. Asparagine aminotransferase (AST)/serum glutamine oxaloacetic transaminase (SGOT), 
alanine aminotransferase (ALT)/serum glutamic-pyruvic transaminase (SGPT) 
≤3.0 × upper limit of normal (ULN) (≤5 × ULN if known liver involvement) 
e. Total bilirubin ≤2.0 × ULN unless considered due to Gilbert’s syndrome in which case, 
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f. Estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.732 m2 by Modification 
of Diet in Renal Disease (MDRD) equation 
g. Prothrombin time (PT) ≤1.5 × ULN 
h. International normalized ratio (INR) ≤1.5 × ULN 
i. Serum potassium and magnesium should be within normal limits for institution 
or treatment to correct out of range values should be instituted 
11. Willingness to participate in collection of all required laboratory testing as defined in the 
protocol 
12. Females must be surgically sterile, postmenopausal, or agree to use adequate contraception 
(adequate as determined by the judgement of the Investigator) throughout the study and for 
a period of 6 months after last dose of VRx-3996 
13. Males must be surgically sterile or must agree to use of effective contraception throughout 
the study and for a period of 3 months after last dose of VRx-3996 
4.2. 
Exclusion Criteria 
1. Fewer than 14 days from prior anti-lymphoma therapy (chemotherapy, irradiation, biological, 
or investigational therapy), or fewer than 7 days from prior therapies if approved by the 
Medical Monitor. Corticosteroid treatment at doses of ≤20 mg/day of prednisone or its 
equivalent, granulocyte colony-stimulating factor (G-CSF) or granulocyte-macrophage 
colony-stimulating factor (GM-CSF) are permitted up to 2 weeks prior to start of study 
treatment. 
2. Fewer than 28 days from receipt of prior HDAC inhibitor 
3. Fewer than 60 days from prior hematopoietic stem cell transplantation or solid organ 
transplantation  
4. Known primary CNS lymphoma 
5. CNS metastases or leptomeningeal disease unless appropriately treated and neurologically 
stable for at least 4 weeks 
6. Other known active cancer(s) likely to require treatment in the next year that would impact 
the assessment of any study endpoints 
7. Refractory graft versus host disease (GvHD) not responding to treatment (e.g., steroid 
refractory and not responding to second-line agents) 
8. Active, uncontrolled bacterial, viral, or fungal infection(s) requiring systemic therapy 
9. Pregnant or currently breastfeeding 
10. Positive hepatitis B core antibody or surface antigen unless quantitative DNA PCR is 
negative and patient will be receiving prophylaxis for reactivation 
11. Positive hepatitis C viral RNA (if serology is positive for infection) 
12. History of allergic reactions attributed to compounds of similar chemical or biologic 
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13. Psychiatric illness/social situations that would interfere with compliance with study 
requirements 
14. Clinically significant cardiovascular abnormalities such as uncontrolled hypertension, 
congestive heart failure (New York Heart Association classification ≥ II), unstable angina, 
poorly controlled arrhythmias, or myocardial infarction within 6 months of study entry. 
Congenital long QT syndrome or corrected QT interval using Fridericia’s method (QTcF) 
interval of ≥470 msec, average of triplicate readings at screening. 
15. Other severe acute or chronic medical or psychiatric conditions or laboratory abnormalities 
that would impart, in the judgement of the Investigator, Medical Monitor, and/or Sponsor 
representative, excess risk associated with study participation or would interfere with study 
outcome assessments 
16. Known involvement of critical structures by lymphoma that is considered highly likely to 
result in serious outcome in the event of rapid tumor destruction 
17. Known history of HHV-6 chromosomal integration (ciHHV-6) 
18. Known history of HIV infection 
5. 
INVESTIGATIONAL PRODUCTS 
5.1. 
VRx-3996 Drug Substance 
VRx-3996 is a hydroxamic acid-based HDAC inhibitor.18 As is typical of this class, the structure 
of VRx-3996 has 3 main components: a hydroxamic acid that coordinates with the Zn2+ ion in 
the active pocket of the enzyme, a spacer (azabicyclo pyrimidine) that fills out the narrow 
channel of the binding site, and a hydrophobic head group, amino methyl(fluoroquinoline), that 
interacts with the rim surrounding the pocket of the active site. 
Figure 1: 
Structural Formula and Key Features of VRx-3996 
 
 
Specific characteristics of VRx-3996 are outlined in Table 9. 

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Table 9: 
Drug Substance Properties 
Molecular formula 
C20H19FN6O2 
Molecular weight 
394.40 
Physical description 
Off-white to pale orange solid 
LogP 
1.60 (neutral); -1.0 (cationic) 
5.1.1. Acquisition 
VRx-3996 will be provided by the Sponsor to each clinical site. Instructions for requesting 
and receiving VRx-3996 will be included in the Study Manual. 
5.1.2. Dosage Form 
VRx-3996 drug product is currently supplied as 5 mg strength capsules. In addition to active 
ingredient nanatinostat, inactive excipients consist of silicified microcrystalline cellulose 
and sodium stearyl fumarate, which are dry-filled into size 2, white to off-white, opaque, hard 
gelatin capsules for oral administration. 
Viracta intends to introduce film-coated immediate-release (IR) tablets of 5 mg and 10 mg 
strengths in this study, replacing the capsule product. The tablets are dose proportional, 
consisting of the active VRx-3996, and inactive excipients (i.e., mannitol, microcrystalline 
cellulose, croscarmellose sodium, and sodium stearyl fumarate). The tablets are film coated with 
non-functional Opadry II white. The comparability between the tablets and capsules has been 
established via in vitro dissolution studies and in vivo dog pharmacokinetic studies and no dose 
adjustment is needed. 
All of the inactive ingredients in the drug product meet compendial requirements of the United 
States Pharmacopeia and/or National Formulary. 
5.1.3. Composition 
The quantitative compositions for 5 mg VRx-3996 capsules are presented in Table 10. 
Table 10: 
Quantitative Composition of VRx-3996 Capsules 
Components 
5 mg 
Amount per Capsule (mg) 
Weight (%) 
VRx-3996 
5.01 
2.5 
Silicified microcrystalline cellulose 
194.0 
97.0 
Sodium stearyl fumarate 
1.0 
0.50 
Total (Blend) 
200.0 
100.00 
Capsule Size 
61.02 
--- 
Total (filled capsule) 
261.0 
--- 
1 Exact amount is corrected for drug substance assay (free base on the anhydrous, solvent free basis) 
2 Average capsule weights as provided by manufacturer 
 

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The quantitative compositions for the dose proportional 5 mg and 10 mg VRx-3996 tablets are 
presented in Table 11. 
Table 11: 
Quantitative Composition of Film-Coated, Immediate-Release VRx-3996 
Tablets (5 and 10 mg Strengths) 
Component 
Function 
% w/w 
5 mg strength 
(mg/tablet) 
10 mg strength 
(mg/tablet) 
VRx-3996 
Drug substance 
5.0 
5 
10 
Mannitol 
Filler 
25.0 
25 
50 
Microcrystalline cellulose 
Filler 
65.5 
65.5 
131 
Croscarmellose sodium 
Disintegrant 
4.0 
4.0 
8.0 
Sodium stearyl fumarate 
Lubricant 
0.5 
0.5 
1.0 
Total (core) 
100 
100 
200 
Opadry II coating powder 
Film coating   
3.0 
3.0 
6.0 
Purified water* 
Film coating 
- 
- 
- 
Total 
103 
206 
* Used to make the coating solution and removed during processing 
5.1.4. Product Packaging 
VRx-3996 Capsules, 5 mg, are packaged in 30-count high-density polyethylene bottles, sealed 
and closed with child-resistant caps. 
VRx-3996 film-coated Tablets, 10 mg and 5 mg, are packaged in 45-count high-density 
polyethylene bottles, sealed and closed with child-resistant caps. 
5.1.5. Product Storage and Stability 
VRx-3996 should be stored at controlled room temperature 20–25ºC (68–77ºF), with excursions 
permitted to 15–30ºC (59–86ºF) in a secure location. Once the bottle seal is broken, bottles 
should be stored tightly capped. 
5.1.6. Dosing and Administration 
VRx-3996 will be administered in the Phase 1b portion of the study at a dose and schedule 
determined by the assigned cohort. 
In the Phase 2 portion of the study, patients will receive VRx-3996 at the RP2D and schedule 
determined in the Phase 1b portion of the study. 
5.1.7. Dietary Requirements 
There are no special dietary restrictions or requirements associated with VRx-3996; however, 
valganciclovir absorption is affected by food and should be taken with food (see Section 5.2.4 
for additional clarification). 

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5.1.8. Dose Adjustments/Modifications/Delays 
Given the expectation that both study drugs are required for activity, both agents will be held 
and restarted in parallel unless toxicity is clearly associated with VRx-3996 and there is clinical 
justification to continue dosing with valganciclovir alone. For non-hematologic toxicity requiring 
dose modification see Table 12.  
Table 12: 
Requirements for Dose Hold Secondary to Non-Hematologic Toxicity 
Toxicity (CTCAE) 
Requirement for Dose Hold 
Grade 1 or 2 
No dose hold required 
Grade 3+ 
Hold subsequent dosing until toxicity has resolved to at 
least Grade 1 or baseline 
 
In the event that any of the following hematologic AEs are observed on study, the dose of 
VRx-3996 and valganciclovir will be held: 
• ANC <500 cells/µL 
• PLT count <35,000/µL 
• Hemoglobin (HGB) is <8 g/dL 
If a hold is implemented for study drug-related toxicity, patients may restart study drugs only if 
the following conditions are met or if agreed with the Medical Monitor: 
• The AE has resolved to at least Grade 1 or baseline for non-hematologic AEs 
and Grade ≤2 hematologic toxicity related to study drug 
• The AE is not expected to recur in the opinion of the Investigator with subsequent study 
drug administration based on an intervention such as prophylactic use of appropriate 
treatment (e.g., prophylactic anti-emetics), or a reduction in the dose of one or both of the 
study drugs 
• Continued administration of study drugs is considered to be in the patient’s best interest 
based on the opinion of the study Investigator 
Patients should be followed up approximately twice weekly for resolution of the toxicity. Study 
days will continue to accrue during dose holds and other scheduled procedures as per Table 15 
should not be delayed. If the dose is held for more than 14 days, the Investigator should consult 
with the Medical Monitor before dosing resumes. 
If a patient has multiple dose interruptions for study drug toxicity or has had to interrupt for more 
than 14 days, a dose reduction should be considered. Dose reduction for VRx-3996 will be in 
10 mg increments and for valganciclovir from 900 mg to 450 mg. Re-escalation of study drug 
dose may only be performed after approval by Medical Monitor. 
There are additional criteria for modification of the valganciclovir dose based on renal function 
as outlined in Section 5.2.3. 

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5.2. 
Valganciclovir 
5.2.1. Acquisition 
Valganciclovir tablets will be provided to the clinical sites from commercial sources by the 
Sponsor. Instructions for requesting and receiving valganciclovir will be included in the 
Pharmacy Manual. 
5.2.2. Product Storage and Stability 
Valganciclovir should be stored at controlled room temperature 20–25ºC (68–77ºF), with 
excursions permitted to 15–30ºC (59–86ºF) in a secure location. 
5.2.3. Dosing and Administration 
In the Phase 1b portion of the study, the starting dose of valganciclovir is listed in Table 5. 
If a patient is on valganciclovir prior to study entry, the dose of valganciclovir should be 
increased to the dose and schedule listed for their assigned cohort in Table 5. Patients who have 
previously shown intolerance to a given dose of valganciclovir, should start at their highest 
tolerable dose of valganciclovir or their assigned dose (whichever is lower) following discussion 
with the Medical Monitor. For those patients with evidence of renal impairment at study entry, 
the starting dose of valganciclovir should be discussed with the Medical Monitor but should be 
no higher than the doses listed in Table 13. 
In the Phase 2 portion of the study, the starting dose and schedule of valganciclovir (i.e., RP2D) 
will be determined by the SRC at the conclusion of the Phase 1b portion of the study. If a patient 
is on valganciclovir prior to study entry, the dose of valganciclovir should be increased to the 
RP2D. Patients who have previously shown intolerance to a given dose of valganciclovir, should 
start at their highest tolerable dose of valganciclovir or the RP2D (whichever is lower) following 
discussion with the Medical Monitor. For those patients with evidence of renal impairment at 
study entry, the starting dose of valganciclovir should be discussed with the Medical Monitor but 
should be no higher than the dose listed in Table 13. 
In either phase of the study, patients who develop an elevated creatinine while on study should 
have their dose of valganciclovir reduced to no higher than the doses listed in Table 13. For 
patients already receiving a dose of valganciclovir lower than that recommended in Table 13, 
the Investigator should discuss the amount of dose reduction with the Medical Monitor. 
Table 13: 
Valganciclovir Dose Adjustments for Adult Renal Impairment 
Creatinine clearance (mL/min) 
Valganciclovir dose 
≥60 
900 mg once daily 
40–59 
450 mg once daily 
25–39 
450 mg every 2 days 
10–24 
450 mg twice weekly 
<10 (on hemodialysis) 
Not recommended (discuss with Medical Monitor) 
 

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In patients who are unable to tolerate oral dosing of valganciclovir, the Investigator will have the 
option of administering ganciclovir IV at 5 mg/kg IV BID. In patients who are receiving a dose 
of valganciclovir less than 900 mg PO BID, the dose of ganciclovir will be reduced accordingly 
using the ratio of 900 mg valganciclovir to 5 mg/kg ganciclovir. 
The SRC may elect to adjust the starting dose or schedule of valganciclovir as appropriate during 
the conduct of the study. 
5.2.4. Dietary Requirements 
Valganciclovir absorption is affected by food. Therefore, patients should be instructed to take 
both valganciclovir and VRx-3996 with food. 
In an effort to standardize food intake for the PK assessments, patients will be asked to consume 
one can of Ensure® or equivalent prior to the dose of study drugs on days with pre- and post-dose 
PK assessments as outlined in Section 6.4.1. Note that valganciclovir and VRx-3996 should be 
taken at the same time, including on Cycle 1 Day 1. An Ensure equivalent is defined as any 
liquid nutrition that is at least 8 ounces in size containing at least 8 grams of protein and at least 
6 grams of fat. Alternatively, patients may consume a light breakfast in place of consuming 
an Ensure equivalent. 
Patients are free to determine what food to take prior to all subsequent study drug 
administrations. On study visit days requiring PK trough levels, patients should be instructed to 
bring food to consume prior to dosing in order to avoid taking study drugs on an empty stomach 
and reduce disruption in their dosing schedule. 
5.2.5. Dose Adjustments/Modifications/Delays 
Dose adjustments for valganciclovir will be made in concert with adjustments to VRx-3996. 
See Section 5.1.8 for specific details. 
For patients with renal impairment, dose adjustments for valganciclovir will be made in 
accordance with valganciclovir prescribing guidelines as outlined in Table 13. 
5.2.6. Drug Interactions 
The drug-drug interactions for valganciclovir are those seen with ganciclovir. Drug-drug 
interaction studies with ganciclovir were conducted in patients with normal renal function. 
Therefore, with concomitant administration of valganciclovir and other renally excreted drugs, 
patients with impaired renal function may have increased concentrations of ganciclovir 
and/or the co-administered drug. Such patients should be closely monitored for toxicity of 
ganciclovir and the co-administered drug. Established and other potentially significant drug 
interactions conducted with ganciclovir are listed in Table 17 in the Appendix. 
In patients that are receiving a concomitant medication considered to pose a significant drug 
interaction with valganciclovir, additional monitoring should be conducted as outlined in 
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5.3. 
Missed Doses 
If a scheduled dose of VRx-3996 or valganciclovir is missed, the patient should take the missed 
dose(s) as soon as possible during the same day, but within 8 hours of the missed dose. If more 
than 8 hours or an entire day has passed, the normal dosing schedule will be resumed the 
following day without a change in the daily dose or schedule. 
5.4. 
Vomited Doses 
If a scheduled dose of VRx-3996 or valganciclovir is vomited, the patient should contact the site 
for consideration of anti-nausea medication and dosing should resume with the next scheduled 
dose. No replacement dose should be given. 
5.5. 
Assessment of Study Drug Compliance 
Patient compliance with study drugs will be assessed during study participation. The specific 
method used to assess study drug compliance may include paper diaries or an automated 
phone-based system to collect study drugs capsule/tablet counts. Details on the specific method 
used will be included in the Study Manual. 
5.6. 
Study Drug Accountability 
The Investigator or their representative will account for all study drugs supplied by the Sponsor. 
The Investigator shall maintain adequate records of the disposition of study drug, including 
dates, quantity, and use by patients. Upon completion of the study, all remaining study drugs will 
be accounted for and returned to the Sponsor via a traceable method (UPS, FedEx, Marken, etc.) 
or disposed following the institution’s Standard Operating Procedures (SOPs), if instructed by 
the Sponsor. 
6. 
STUDY PROCEDURES AND SCHEDULE 
6.1. 
Informed Consent 
Written informed consent (ICF) in a language fully comprehensible to the prospective patient 
will be obtained from each patient prior to performing any study-related procedures. A copy 
of the signed ICF will be provided to the patient. The study site will retain all original versions 
of signed ICFs. 
6.2. 
Patient Registration 
Clinical sites will submit Patient Registration materials through an electronic system for Medical 
Monitor approval prior to the initial administration of study drugs. Details on the specific 
electronic system and procedures will be included in the Study and Pharmacy Manuals. 
Administration of study drugs should begin within 14 days of approval by the Sponsor 
(or designee). 
6.3. 
Study Specific Procedures 
Study procedures will follow those outlined in the Schedule of Events in Table 15. 

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6.3.1. End of Treatment Visit 
The End of Treatment (ET) Visit is the visit at which the decision is made to discontinue 
administration of VRx-3996. 
If the decision is made to discontinue administration of VRx-3996 outside of a scheduled visit, 
an attempt will be made to have the patient return for an ET visit. 
6.3.2. Safety Follow-Up Visit 
Safety will be assessed at the Safety Follow-Up Visit, approximately 28 days following the final 
administration of VRx-3996/valganciclovir. 
6.3.3. Survival and Follow-up Assessment 
Survival and follow-up assessment will be conducted at least every 3 months for assessment 
of additional therapy, response status, and survival following the safety follow-up assessment. 
This assessment may be conducted by review of the patient records or by patient contact 
(e.g., telephone, email). Patients who are unable to be contacted following at least 3 attempts 
(one of which is contact by registered mail) will be considered lost to follow-up. 
6.3.4. Unscheduled Visit 
Unscheduled visits will be recorded in the database. The specific tests and evaluations performed 
during an unscheduled visit will be determined by the Investigator. 
6.4. 
Clinical Laboratory Evaluations 
Clinical laboratory evaluations will follow those outlined in the Schedule of Events in Table 15. 
Clinical laboratory evaluations will be performed using a central laboratory or a local laboratory. 
In addition, the clinical sites will provide archived or fresh tissue samples at baseline and in the 
event of a relapse, if diagnostic biopsies are performed. 
6.4.1. Pharmacokinetics 
Phase 1b/2 and Tablet Cohorts 
A PK assessment of both VRx-3996 and valganciclovir will be performed following the first 
administration of VRx-3996/valganciclovir in all patients. The scheduled timepoints are shown 
in Table 14. 

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Table 14: 
Pharmacokinetic Sampling and ECG Schedule for Valganciclovir 
and VRx-3996  
Time 
Administration 
PK Sampling and ECG Schedule 
Cycle 1 & 2, Day 1 
 
Plasma 
ECG 
Urine (Cycle 1 
only) 
Pre-dose*** 
Meal supplement* 
X 
X (triplicate) 
Void 
0 hour 
Valganciclovir and VRx-3996 
 
 
N/A 
0.5 hour (±15 min) 
 
X 
X (triplicate) 
0–3 hr collection 
1 hour (±15 min) 
 
X 
X (triplicate) 
2 hour (±15 min) 
 
X 
X (triplicate) 
4 hour (±15 min) 
 
X 
X (triplicate) 
3–8 hr collection 
6 hour (±15 min) 
 
X 
X (triplicate) 
8 hour (±30 min) 
 
X 
 
Cycle 1 Day 2** 
 
 
 
 
Pre-dose*** 
Meal supplement* 
X 
X (triplicate) 
N/A 
0 hour 
Valganciclovir and VRx-3996 
 
 
N/A 
2 hour (±15 min) 
 
X 
X (triplicate) 
N/A 
Cycle 1 & 2, Day 
15** 
 
 
 
 
Pre-dose*** 
Meal supplement* 
X 
X (triplicate) 
N/A 
0 hour 
Valganciclovir and VRx-3996 
 
 
N/A 
2 hour (±15 min) 
 
X 
X (triplicate) 
N/A 
* 
Ensure or equivalent should be consumed prior to dosing. Alternatively, patients may consume a light breakfast in place of 
consuming an Ensure or equivalent. 
** 
Patients should be reminded not to take their dose at home prior to coming into the clinic on these days. Study visits with 
PK assessments should occur on days that the patient will take both study drugs, VRx-3996 and valganciclovir. 
*** Pre-dose ECG should be conducted prior to meal supplement. If possible, patients should not consume additional food 
between dose and last ECG timepoint. If 6 hr fasting time for ECGs is not feasible for patients, a high protein, low carb 
snack immediately following an ECG to maximize the time between food and the next ECG. 
 
At selected sites, urine will be collected for levels of VRx-3996 and its metabolites Cycle 1 
Day 1. Patients will be instructed to void urine prior to administration of study drug, then all 
urine will be collected between 0 and 3 hours, and 3 and 8 hours. Detailed instructions are 
included in the Study Manual. 
Pharmacokinetic analysis will be performed at a central laboratory designated by the Sponsor. 
Instructions on the collection, processing, and shipment of patient PK samples for these assays 
will be provided in the Laboratory Manual. 
If available, back-up PK aliquots may be used for future assessment of VRx-3996 metabolites 
(if identified). 

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6.4.2. Exploratory Biomarkers 
Exploratory biomarkers will be evaluated in this study as indicated in Table 15. Archived blood, 
PBMCs, plasma, and/or tissue samples may be used for assessment of other exploratory 
biomarkers (if identified). 
Details on the collection procedure and timing for each exploratory biomarker will be provided 
in the Study Manual. 
7. 
SCHEDULE OF EVENTS 
The study procedures for the Phase 1b and Phase 2 portions of the study will follow those 
outlined in Table 15. 
Table 15: 
Schedule of Events 
Cycle 
SR 
1 
2 
3+ 
ET 
ST 
SV 
Cycle Day 
 
1 
2 
8 
15 
22 
1 
15 
1 
15 
 
 
 
Assessment 
 
 
 
 
 
 
 
 
 
 
 
 
 
Informed consent 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Medical history 
(includes donor data) 
X 
 
 
 
 
 
 
 
 
 
 
 
 
EBER/histology sample  
X 
 
 
 
 
 
[X] 
 
[X] 
 
[X] 
 
 
Height 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Physical examination 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Symptom-directed exam 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Vital signs 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Performance status 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Adverse events 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Concomitant medications 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Urinalysis 
X 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Hematology  
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Chemistry 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Coagulation 
X 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Serum pregnancy test 
X  
 
 
 
 
 
 
 
 
 
 
 
 
Urine pregnancy test 
 
X 
 
 
 
 
X 
 
X 
 
 
 
 
12-lead ECG 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Head CT/MRI 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Disease assessment 
X 
 
 
 
 
 
 
 
X 
 
X 
 
 
PK sample(s)  
 
X 
X 
 
X 
 
X 
X 
 
 
 
 
 
Urine PK sample collection 
 
X 
 
 
 
 
 
 
 
 
 
 
 
Hepatitis B antigen/antibodies 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Hepatitis B DNA PCR 
X  
 
 
 
 
 
 
 
 
 
 
 
 
Hepatitis C antibodies 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Hepatitis C qPCR 
X 
 
 
 
 
 
 
 
 
 
 
 
 

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Cycle 
SR 
1 
2 
3+ 
ET 
ST 
SV 
HLA testing 
 
X 
 
 
 
 
 
 
 
 
 
 
 
Exploratory Biomarkers 
 
 
 
 
 
 
 
 
 
 
 
 
 
  -Histone H3 acetylation 
 
X 
X 
X 
 
 
X 
 
 
 
 
 
 
  -Immune profile  
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
 
  -EBV and CMV qPCR 
 
X 
X 
X 
X 
X 
X 
 
X 
 
 
 
 
VRx-3996/valganciclovir 
distribution  
 
X 
 
 
 
 
X 
 
X 
 
 
 
 
VRx-3996/valganciclovir 
return 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
VRx-3996/valganciclovir 
compliance assessment 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Survival and follow-up 
assessment and disease status 
 
 
 
 
 
 
 
 
 
 
 
 
X 
Study assessments may be performed ±3 days of the recommended date (however the DLT assessment period should 
include a full 28 days). Study visits with PK assessments should occur on days that the patient will take both study 
drugs, VRx-3996 and valganciclovir. End of Treatment (ET) Visit assessments (if needed) will be the same as for the 
Safety Follow-Up Visit. Safety Follow-Up Visit will be performed 28 ±7 days after last dose. 
SR – Screening (within 21 days of Cycle 1 Day 1) 
ET – End of Treatment 
ST – Safety follow-up 
SV – Survival follow-up contact (performed at least every 3 months after safety follow-up assessment) 
X – Required 
[X] – Biopsy tissue samples taken per standard of care during study participation and samples taken at the time 
of relapse should be submitted to the central pathology lab for review. 
Informed consent – Informed consent may be performed at any time prior to the start of screening procedures. 
EBER/histology Sample – Histology sample, indicative of current disease, to be sent to central pathology lab at the 
time of screening. Central pathology review/results not required for enrollment. Pathology review will include 
detection of EBV gene products. 
Medical history – Record all cancer-related history over the patient’s lifetime and collect non-cancer related 
history for the 2 years prior to study entry. For transplant recipients (except auto-SCT), collect the following 
historical information on donors:  HIV1, HIV2, hepatitis B surface Ag, hepatitis B surface Ab, hepatitis B core 
Ab, hepatitis C Ab, HSV-1 Ab, HSV-2 Ab, CMV Ab IgG, CMV Ab IgM, EBV IgG-VCA (viral capsid antigen). 
Vital signs – Performed just prior to first dose of valganciclovir and VRx-3996, and in concert with (but prior to) 
PK draws on Cycle 1 Day 1. On other indicated visit days, perform vital signs once (prior to study drugs 
dosing if administered in clinic). Vital signs include weight (in pounds), heart rate, respiratory rate, blood 
pressure, temperature, and oxygen saturation by pulse oximeter. Note that weight only needs to be recorded 
once daily. 
Performance status – Either ECOG or KPS (See Table 16 in the Appendix for conversion table). 
Concomitant medications – Recorded from 28 days prior to Cycle 1 Day 1 to 28 days after last dose of study drugs, 
except for concomitant medications related to cancer treatment, for which lifetime history prior to entering the 
study will be recorded.  
Urinalysis – [Urine] Color, appearance, glucose, bilirubin, ketone, specific gravity, blood, pH, protein, 
urobilinogen, nitrite, leukocyte esterase, RBC, WBC, epithelial cells. 
Hematology - [Blood] Complete blood count with differential to include WBC, RBC, HGB, HCT, platelets, MCV, 
MCH and differential. 
Chemistry - [Blood] Sodium, potassium, chloride, bicarbonate, blood urea nitrogen, creatinine, glucose, calcium, 
phosphate, magnesium, AST, ALT, total bilirubin, alkaline phosphatase, total protein, albumin, uric acid, 
and LDH. 

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Coagulation – [Blood] PT, PTT, and INR. 
Serum pregnancy test – Only required for females of child-bearing potential. 
Urine pregnancy test – Only required for females of child-bearing potential at the beginning of every cycle. 
12-lead ECG – Careful skin preparation should be done to assure high quality ECGs and all ECGs should be 
collected on the same ECG machines. ECGs should be performed in as calm an environment as possible 
and not immediately following stressful procedures (i.e., biopsies, etc.) and distractions should be minimized, 
such as talking, TV, etc. Prior to each ECG, the patient should lie in a supine position in a calm environment 
for at least 5 minutes. When performed in triplicate, the ECGs should be performed ~1 minute apart. ECGs 
should be conducted prior to and as close to PK blood draws when timepoints coincide, followed by vital 
signs, when all 3 assessments are scheduled for the same time (in order: ECG, vital signs, then blood draw). 
ECGs should be performed in triplicate at the following times: 
• 
Screening 
• 
Cycle 1 Day 1 pre-dose, and post-dose at 0.5 hr, 1 hr, 2 hr, 4 hr, and 6 hr 
• 
 Cycle 1 Day 2 pre-dose and post-dose at 2 hr 
• 
Cycle 1 Day 15 pre-dose and post-dose at 2 hr 
• 
Cycle 2 Day 1 pre-dose and post dose at 0.5 hr, 1 hr, 2 hr, 4 hr, and 6 hr 
• 
Cycle 2 Day 15 pre-dose and post dose at 2 hr 
Average corrected QT interval using Fridericia’s method (QTcF) to be calculated to confirm eligibility.  
At times not listed above, single ECGs should be performed. When performed on days that include PK draws, 
a single ECG should be performed as close as possible to each PK draw. For days when there are no 
scheduled PK draws, the ECG can be performed at any time during the clinic visit, irrespective of the time of 
study drug dosing. On study days requiring a single ECG, if ECG indicates an increased QTcF interval 
(i.e., >450 msec), 2 additional ECGs should be performed at least 2 minutes apart. 
Head CT/MRI – Performed to rule out occult CNS disease prior to study entry. 
Disease assessment – Performed at least every 2 cycles with initial assessment after Cycle 2 (may be adjusted based 
on Investigator discretion following discussion with Medical Monitor). Disease assessment performed using 
a modality appropriate for the patient’s tumor (e.g., PET-CT scan, CT scans, MRI). Use a consistent modality 
for the same patient throughout the study. May include assessment of bone marrow (e.g., aspirate, biopsy) with 
cytogenetics and/or fluorescence in situ hybridization (FISH) as indicated. Disease assessment data including 
actual scan data and radiology reports will be submitted to the Sponsor as it becomes available for evaluation 
by a central radiologist reader. Investigator assessment of clinical response will be documented in the source 
and in Electronic Data Capture. When available, tumor tissue collected during the study should be provided to 
the central pathology lab. 
PK sample(s) – [Blood] Collected for both valganciclovir and VRx-3996. Timepoints per Section 6.4.1. Collection 
procedure outlined in the Study Manual for all sites. Study visits with PK assessments should occur on days 
that the patient will take both study drugs, VRx-3996 and valganciclovir.  
Urine PK collections – At selected sites only urine will be collected for levels of VRx-3996 and its metabolites on 
Cycle 1 Day 1. Patients will be instructed to void urine prior to administration of study drug, then all urine 
will be collected as described in Table 14 depending on the patient Cohort. Detailed instructions are included 
in the Study Manual. 
Hepatitis B antigen/antibodies – [Blood] Includes surface antigen, core antibody, and surface antibody. Collection 
procedure outlined in the Study Manual. 
Hepatitis B DNA PCR – [Blood] Collected on patients with positive hepatitis B core Ab or surface Ag. 
Hepatitis C antibodies – [Blood] Collection procedure outlined in Study Manual. Any patient positive for hepatitis 
C Ab will be evaluated for hepatitis C circulating virus by qPCR. 
Hepatitis C qPCR – [Blood] Required only for patients with evidence of hepatitis C based on serology. 
Human leukocyte antigen (HLA) testing – [Blood] Determination of HLA class I and II. Collection procedure 
outlined in the Study Manual. 

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Exploratory biomarkers: 
  -Histone H3 acetylation – [Blood] Evaluates acetylation on PBMCs. Samples collected prior to administration 
of study drugs on Cycle 1 Day 1 (baseline), Cycle 1 Day 2, Cycle 1 Day 8. Collection procedure outlined in the 
Study Manual. 
  -Immune profile – [Blood] Evaluates immunophenotype and immune function in PBMCs. Samples are collected 
prior to administration of study drugs on Cycle 1 Day 1 (baseline), Cycle 1 Day 15, Cycle 2 Day 1, Cycle 3 
Day 1, Cycle 4 Day 1, and ET. Collection procedure outlined in the Study Manual. 
  -EBV and CMV qPCR- [Blood] Collected prior to administration of study drugs on Cycle 1 Day 1 (baseline), 
Cycle 1 Days 2, 8, 15, 22, and Cycles 2–12 Day 1. Collection procedures are outlined in the Study Manual. 
8. 
STUDY COMPLETION 
8.1. 
Early Study Termination 
If the Sponsor elects to terminate the study prematurely, the Sponsor will provide appropriate 
notification to the Investigators, Institutional Review Boards (IRBs), and FDA and other relevant 
regulatory authorities as applicable. The notification will include instructions for handling 
patients still on study drug, data collection procedures, and requirements for study close-down. 
8.2. 
Patient Discontinuation 
Prior to discontinuing a patient, every effort should be made to contact the patient, schedule 
a final study visit, obtain as much follow-up data as possible, and retrieve all study material. 
An attempt will be made to collect survival data whenever possible, unless the patient has 
withdrawn consent for all study-related activities.  
8.3. 
Lost to Follow-Up 
Patients who do not return for scheduled visits and who cannot be contacted, will be considered 
lost to follow-up. Follow-up attempts will be documented in the source documents and the 
applicable sections of the eCRF. 
9. 
ASSESSMENT OF SAFETY 
9.1. 
Specification of Safety Parameters 
9.1.1. Adverse Event (AE) Definition 
An AE is any untoward medical event that occurs to a patient following the start of 
investigational product (IP) administration, whether the event is considered IP-related or not. 
Pre-existing conditions are not considered an AE unless the condition worsens by at least 1 grade 
following the start of IP administration. 
Adverse events will be captured with the first dose of study drugs (on Cycle 1 Day 1) 
and continue until 28 days after the last dose of study drugs or until a new anticancer treatment is 
started. 

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Death considered related to disease progression will not be considered an AE. However, all 
deaths within 28 days of last study drug administration or assessed as related to study drug, must 
be reported on a serious adverse event (SAE) form within 24 hours. 
9.1.2. Abnormal Laboratory Tests 
Laboratory test abnormalities that constitute an adverse event (i.e., are considered to be clinically 
significant, induce clinical signs or symptoms, require concomitant therapy or require changes in 
study treatment) should be recorded in the eCRF. If possible, a diagnosis rather than a symptom 
should be provided (e.g., anemia instead of low hemoglobin). Laboratory abnormalities that meet 
the criteria for AEs should be followed until they return to normal or an explanation for the 
abnormality is determined. When abnormal results are due to toxicity, patients should be 
assessed twice weekly for resolution. 
Laboratory abnormalities that do not meet the definition of an AE should not be reported as 
adverse events. If a dose hold or concomitant medication for the lab abnormality is required, this 
would be considered an AE by definition and must be reported as such.  
9.1.3. Definition of Serious Adverse Events (SAE) 
An SAE is any AE that results in any of the following outcomes: 
• Death 
• A life-threatening experience 
• An inpatient hospitalization or prolongation of an existing hospitalization 
• A persistent or significant disability/incapacity 
• A congenital anomaly/birth defect 
• An event that is not listed above but that requires intervention to prevent one of the 
outcomes listed above also is considered a SAE 
Elective hospitalizations for a pre-existing condition that is unrelated to the indication under 
study and has not worsened since signing the informed consent should not be reported as a SAE. 
Hospitalizations related to disease progression should not be reported as a SAE. 
9.2. 
Classification of an Adverse Event 
9.2.1. Severity of Event 
All AEs will be assessed by the Investigator using NCI CTCAE version 5.0. 
9.2.2. Relationship to Study Drugs 
The Investigator will use his/her best medical judgment to determine the relationship of an AE to 
one or both study drugs. 
The relationship of an AE or SAE to study drugs will be classified using the following 
3 categories: 
• Definitely related 
• Possibly related 

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• Unrelated 
To be classified as “Definitely related”, an AE should occur in a timeframe relative to 
administration of study drugs that suggests a strong causal relationship between study drugs 
and the AE. In addition, there should be no other reasonable explanations for the AE, such as 
underlying disease or other concurrent conditions. 
To be classified as “Unrelated”, an AE should occur in a timeframe relative to administration of 
study drugs that suggests a causal relationship between study drugs and the AE is very unlikely. 
In addition, there should be a reasonable explanation for the AE, such as underlying disease 
or other concurrent condition. 
To be classified as “Possibly related”, an AE should not fall clearly into 1 of the above 2 
categories. This would include, for example, an AE that does not seem to occur in close temporal 
proximity to administration of study drugs, but also has no other reasonable explanation. 
9.2.3. Expectedness 
The Investigator will make an assessment of whether an AE is expected or unexpected. An AE 
will be considered unexpected if the nature, severity, or frequency of the event is not consistent 
with the reference safety information described in the Investigator Brochure for the study drugs. 
Expectedness refers to AEs previously observed, not to what might be anticipated from the 
properties of the study agent or what has been seen with agents of the same class. 
9.3. 
Time Period for AE Reporting 
Adverse Events will be recorded that occur following the first administration of study drugs 
(on Cycle 1 Day 1) up to and including 28 days after the last dose of study drugs or until the start 
of a new anticancer therapy. 
10. 
ASSESSMENT OF EFFICACY 
Response will be assessed locally using a combination of physical exam and imaging 
(e.g., PET-CT scan, CT scan MRI, bone marrow/aspirate) as appropriate for each patient. 
Response assessments will follow the Recommendations for Initial Evaluation, Staging, 
and Response Assessment of Hodgkin and Non-Hodgkin Lymphoma: The Lugano 
Classification.22 
Response assessments may also be conducted centrally using the RECIL criteria.23 
11. 
REPORTING PROCEDURES 
11.1. Serious Adverse Event Reporting 
All SAEs must be reported to the Sponsor within 24 hours of the Investigator becoming aware of 
the SAE. The time period for reporting SAEs will follow that for AEs as outlined in Section 9.3. 
To report a SAE, sites will complete an SAE Report Form and email the report to: 
CTISafety@ctifacts.com 

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or 
Fax to 1-866-366-2329 
The Investigator should discuss with the Medical Monitor any SAEs for which the issue of 
seriousness is unclear or questioned. Contact information for the Medical Monitor is: 
Name: John Gutheil, MD 
Phone: 1-858-248-0639 
Email: jgutheil@sciquus.com 
SAEs must be reported by each site to their appropriate IRB/Ethics Committee (EC) in 
accordance with the timeframes and procedures required by their IRB Policy. 
The Sponsor will report SAEs to the US FDA and any other relevant regulatory authorities. 
11.2. Reporting of Pregnancy 
Pregnancies occurring in study patients will be reported to the Sponsor within 24 hours of 
becoming known to the site. A Pregnancy Report Form provided by the Sponsor will be 
completed. Pregnancies may also be reported to the IRB as per the IRB’s requirements. 
All pregnancies will be followed to term. Every effort will be made to obtain the health status of 
the mother and infant or the fetus (in cases of miscarriage or therapeutic abortion). 
11.3. Overdose 
An overdose is defined as the intake of a study drug in excess of the prescribed daily dose. Since 
both study drugs are in solid form, this would involve taking an additional 5 mg capsule of 
VRx-3996 or an additional 450 mg tablet of valganciclovir over the intended dose. 
All overdoses, whether accidental or intentional, should be reported on an SAE form whether 
or not an AE occurred. If an overdose resulted in an AE, the SAE form should specify the event 
and explain in the narrative that the event was associated with an overdose. 
12. 
STATISTICAL CONSIDERATIONS 
12.1. Analysis Datasets 
This study will identify the following datasets: 
• Intent to treat dataset: All patients who have enrolled in the study 
• Safety dataset: All patients who receive at least 1 dose of VRx-3996.  
• Efficacy dataset: All patients with measurable disease at Screening who have met all 
inclusion criteria and have received at least 1 post-baseline tumor assessment for 
efficacy. 
12.2. Description of Statistical Methods 
Analyses performed for this study will utilize descriptive statistics. For continuous variables, 
the following information will be presented by cohort and study phase: n, mean, standard 
deviation, median, minimum, and maximum. Baseline will be the last observation prior to 
treatment. For categorical variables counts and percentages will be used. 

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The clinical outcomes of primary interest are overall response rate (ORR: complete or partial 
response) and duration of response (DoR). Efficacy will be presented as the percentage 
of patients with CRs, PRs, and SD. ORR will be calculated as CR + PR; disease control rate will 
be calculated as CR + PR + SD. Response criteria will follow the recommendations of Cheson 
et al., 2014.28 The analysis of study data will be based on patient data from both the dose 
escalation (Phase 1b) and dose expansion (Phase 2 and Tablet cohort) parts up to the time when: 
i) all Phase 1b patients have completed at least 12 months of follow-up from their first disease 
response assessment after 2 cycles of therapy or have discontinued from the study, and ii) all 
patients have been followed for DoR for a maximum period of 12 months from the first dose of 
study medication, have died, withdrawn consent, discontinued, or are lost to follow up, 
whichever occurs first. The additional data for any patients continuing to receive study drugs or 
remaining in safety or survival follow-up beyond the final cutoff point will be summarized in a 
final Clinical Study Report.  
The ORR and CR rates will be summarized by cohort and study phase with exact 95% 
confidence Intervals (CIs). 
Duration of response is defined as time from date of first observed complete or partial response 
to the date of disease progression, death due to any cause, or last adequate (radiographic) 
response assessment. The DoR will be estimated for the RP2D dose patients using Kaplan- 
Meier estimates where patients still on treatment after 12 months will be censored. 
12.3. Analysis of the Primary Endpoints 
12.3.1. Safety Profile 
The safety dataset will be used for all the safety summaries. 
The incidence of all AEs will be tabulated by dose received. These AEs will be classified by 
System Organ Class and preferred term using the Medical Dictionary for Regulatory Activities 
(MedDRA). 
For incidence reporting, if a patient reported more than 1 AE that was coded to the same System 
Organ Class or Preferred Term, the patient will be counted only once at the highest observed 
grade for that specific system organ class or preferred term. 
An overview of AEs, which includes patient incidence of AEs, AEs by severity, SAEs, deaths, 
and AEs leading to discontinuation, will be presented. 
A summary of the number DLTs per cohort will be provided. 
Serious adverse events will be listed and summarized in a similar manner to AEs. 
12.3.2. Recommended Phase 2 Dose 
The RP2D will be determined by the SRC after review of all safety and efficacy data available at 
the end of the Phase 1b portion of the study. The RP2D may be no higher than then MTD as 
traditionally determined in oncology studies (e.g., dose at which DLTs are seen in fewer than 
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12.4. Analysis of the Secondary Endpoints 
12.4.1. Pharmacokinetics (PK) 
For all cohorts in Phase 1b and the Tablet cohort of Phase 2, the PK of VRx-3996 
and valganciclovir will be summarized by descriptive statistics. For valganciclovir, PK analysis 
will be conducted on ganciclovir. Pharmacokinetic parameters will be estimated, where 
appropriate, by non-compartmental analysis using statistical computer packages as specified in 
the Statistical Analysis Plan. Graphic evaluation will be used for data analysis where appropriate. 
Pharmacokinetics and fit will be evaluated graphically, and by modeling if sufficient data are 
available. 
Serial blood samples for PK analysis will be collected from all subjects at pre-specified 
timepoints. The following PK parameters of VRx-3996 and ganciclovir may be calculated but 
are not limited to: 
• Area under the concentration-time curve from administration to time t (AUC0-t) 
• Area under the concentration-time curve from administration to infinity (AUC0-∞) 
• Maximum concentration (Cmax) 
• Time to maximum concentration (Tmax) 
• terminal elimination half-life (t½) 
• Apparent volume of distribution (Vz/F) 
• Apparent clearance (CL/F) 
Individual elapsed sampling times will be used in the pharmacokinetic analysis. Cmax and Tmax 
will be obtained directly from the experimental observations. AUC0-t will be calculated using the 
linear trapezoidal rule. 
AUC0-∞ will be calculated according to the following equation: 
𝐴𝐴𝐴𝐴𝐴𝐴0−∞= 𝐴𝐴𝐴𝐴𝐴𝐴0−𝑡𝑡+ ൬𝐶𝐶𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙
𝜆𝜆𝑍𝑍
൰ 
where the Clast is the last quantifiable concentration. 
For the purpose of calculating AUC0-t, when two consecutive plasma concentrations below the 
lower limit of quantification (LLOQ) are encountered after Tmax, all subsequent values will be 
excluded from the analysis. When embedded missing values occur, they will be excluded from 
the analysis. Any quantifiable concentrations at pre-dose will be set to zero.  
12.4.2. Time to Response, PFS, and OS 
• Time to response (TTR): defined as the interval from the start of study drug treatment to 
the first documentation of CR or PR 
• Progression free survival (PFS): defined as the interval from the start of study treatment 
to the first documented date of disease progression or death from any cause, whichever 
occurs first. 
• Overall survival (OS): defined as the time from date of first study drug treatment to date 
of death, for any reason. 
Kaplan Meier statistics will be used to display TTR, PFS and OS. 

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12.5. Analysis of Exploratory Endpoints 
Analysis of all exploratory endpoints will be outlined in subsequent materials provided by the 
Sponsor. 
12.6. Baseline Descriptive Statistics 
The characteristics of all patients entered into the study will be summarized with descriptive 
statistics. 
13. 
CLINICAL MONITORING 
The clinical monitoring plan outlines the nature and frequency of site monitoring. 
14. 
SOURCE DOCUMENTS AND ACCESS TO SOURCE DATA/DOCUMENTS 
Each participating site will develop source documents and maintain appropriate medical 
and research records for this study, in compliance with ICH E6 and regulatory and institutional 
requirements for the protection of confidentiality of patients. Each site will permit authorized 
representatives of the Sponsor and regulatory agencies to examine (and when permitted by 
applicable law, to copy) clinical records for the purposes of quality assurance reviews, audits, 
and evaluation of the study safety, progress, and data validity. 
15. 
QUALITY ASSURANCE AND QUALITY CONTROL  
Quality control procedures will be implemented against data collected centrally. Missing data 
or data anomalies will be communicated to the site(s) for clarification/resolution. 
Applicable procedures will follow written SOPs in compliance with the protocol, GCP, and the 
applicable regulatory requirements. 
The investigational site will provide direct access to all study-related sites, source 
data/documents, and reports for the purpose of monitoring and auditing by the Sponsor, and 
inspection by local and regulatory authorities. 
16. 
ETHICS/PROTECTION OF HUMAN PATIENTS 
16.1. Ethical Standard 
The Investigator will ensure that this study is conducted in full conformity with Regulations for 
the Protection of Human Patients of Research codified in: 
• US Code of Federal Regulations (CFR) applicable to clinical studies: 45 CFR Part 46, 
21 CFR Parts 11, 50, 54, 56, 312 
• ICH E6 
• Declaration of Helsinki (64th WMA General Assembly, Fortaleza, Brazil, October 2013) 
• Applicable local legal and regulatory requirements 

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16.2. Institutional Review Board 
Each participating institution must provide for the review and approval of this protocol and the 
associated informed consent documents on an annual basis and approve any recruitment material 
by an appropriate IRB or EC. 
Protocol amendments require review and approval by the applicable IRB prior to 
implementation. 
Changes to the ICF will be submitted to the appropriate IRB for review and approval. 
At the time of any protocol amendment or change to the informed consent document, 
an assessment will be made regarding the need for re-consenting existing patients. 
16.3. Patient and Data Confidentiality 
The study protocol, documentation, data, and all other information generated will be held in 
strict confidence. No information concerning the study or the data will be released to any 
unauthorized third party without prior written approval of the Sponsor. 
The study patient’s contact information will be securely stored at each clinical site for internal 
use during the study. At the end of the study, all records will continue to be kept in a secure 
location for as long a period as dictated by local IRB and Institutional regulations. 
Study patient research data, which is for purposes of statistical analysis and scientific reporting, 
will be transmitted to and stored by the Sponsor. This will not include the patient’s contact 
or identifying information. Rather, individual patients and their research data will be identified 
by a unique study identification number. The study data entry and study management systems 
used by clinical sites and by the Sponsor will be secured and password protected. At the end 
of the study, all study databases will be de-identified and archived by the Sponsor. 
16.4. Research Use of Stored Human Samples, Specimens or Data 
The Sponsor will be responsible for all stored samples generated during this study. Some 
samples will be stored with specific vendors as appropriate (e.g., PK samples). Samples and data 
will be stored using codes assigned by the clinical data system. Data will be kept in 
password-protected computers. 
16.5. Future Use of Stored Specimens 
Data collected for this study will be analyzed and stored by the Sponsor. After the study is 
completed, the de-identified, archived data will be maintained by the Sponsor and may be made 
available for use by other researchers including those outside of the study. 
With the patient’s approval and as approved by local IRBs, de-identified biological samples will 
be stored by the Sponsor with the same goal as the sharing of data with other researchers, some 
of whom may be outside of this study. 
During the conduct of the study, an individual patient can choose to withdraw consent to have 
biological specimens stored for future research. However, withdrawal of consent with regard to 
biological sample storage will not be possible after the study is completed. 

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17. 
DATA HANDLING AND RECORD KEEPING 
17.1. Data Collection Responsibilities 
The Investigator is responsible for ensuring the accuracy, completeness, legibility, and timeliness 
of the data reported. 
This study will utilize a 21 CFR Part 11-compliant data capture system provided by the Sponsor 
for the purposes of data collection. Specific instructions on the system used for data collection 
will be provided in the Study Manual. Clinical data will be entered directly from the source 
documents. 
17.2. Study Records Retention 
Study documents should be retained for a minimum of 2 years after the last approval of 
a marketing application and until there are no pending or contemplated marketing applications 
in an ICH region or until at least 2 years have elapsed since the formal discontinuation of clinical 
development of the IP. These documents may be retained for a longer period, however, if 
required by local regulations. No records will be destroyed without the written consent of the 
Sponsor. It is the responsibility of the Sponsor to inform the Investigator when these documents 
no longer need to be retained. 
17.3. Publication and Data Sharing Policy 
The Sponsor intends that the data from this study will be presented and published following 
completion of data analysis. This study is registered on clinicaltrials.gov by the Sponsor 
(NCT03397706), and the results will be reported per the International Committee of Medical 
Journal Editors (ICMJE) guidelines for clinical trial reporting 
(http://www.icmje.org/recommendations/). Authorship will be based upon the principles outlined 
in the ICJME guidelines (http://www.icmje.org/recommendations/browse/roles-and-
responsibilities/defining-the-role-of-authors-and-contributors.html). As a broad guideline, to 
ensure representation of centers making substantial contributions to this study, centers enrolling 
at least 2 patients will be invited to suggest an investigator for publication co-authorship. Other 
contributors not meeting authorship criteria will be acknowledged individually should they 
agree. Data derived from the study are the exclusive property of the Sponsor. 
The results of the study may be published or presented by the Investigator(s) following review 
and agreement by the Sponsor. Any publication or presentation of ancillary reports or local site 
outcome data must wait until the primary clinical publication is “in press”. The Sponsor reserves 
the right to withhold the presentation of confidential or proprietary information. 
18. 
COVID-19 PANDEMIC 
18.1. Introduction 
The current pandemic caused by the COVID-19 virus has created, and will continue to cause, 
challenges to health care providers and institutions for the foreseeable future. These challenges 
may interfere with the conduct of clinical studies and may necessitate deviations from the 
approved clinical protocol. Viracta has considered the potential risks and benefits of completing 
this study. The study population comprises patients with a likely fatal outcome and a high unmet 

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medical need, and the Sponsor considers it appropriate to continue the study. However, patients 
must not be placed at an unacceptable risk and the critical scientific value of the study must be 
preserved. This section describes potential modifications to the protocol which will generally be 
considered as acceptable although planned changes must be discussed and agreed with the 
Sponsor. 
The FDA has provided guidance to Industry, Investigators, and IRBs, entitled, “FDA Guidance 
on Conduct of Clinical Trials of Medical Products during the COVID-19 Pandemic.” 
(https://www.fda.gov/regulatory-information/search-fda-guidance-documents/fda-guidance-
conduct-clinical-trials-medical-products-during-covid-19-pandemic) 
18.2. Protocol Modifications 
If, due to the COVID-19 pandemic, the Investigator is unable to follow all protocol procedures 
or considers it against the best interest of the patient to complete all study required visits 
and procedures, the Investigator must develop a plan to ensure patient safety and to be as close as 
possible to compliance with study procedures to preserve the scientific integrity of the study. 
This plan must be reviewed and agreed to by the Sponsor. The patient must be fully informed 
of these changes and information pertaining to how the patient was informed must be recorded in 
source documents. If appropriate, sites may formally document re-consent on an IRB-approved 
consent form or consent addendum to be provided and signed by the patient. 
The following are considered acceptable modifications to the protocol after discussion 
and approval by the Sponsor: 
• The acceptable window around scheduled visits may be adjusted on a patient-by-patient 
basis. 
• For patients in a clinically stable condition after Cycle 1, visits may be reduced to no less 
frequently than once every 2 weeks, and after Cycle 4, to no less frequently than once 
every month. If alternate visit frequencies appear appropriate, the Investigator should 
discuss these with the Medical Monitor and obtain approval. 
• Visits may be conducted virtually by telephone, Google, FaceTime, or another 
appropriate modality. Patient confidentiality must be maintained to the extent possible 
(see https://www.hhs.gov/hipaa/for-professionals/special-topics/emergency-
preparedness/notification-enforcement-discretion-telehealth/index.html). 
• For remote visits, laboratory tests may be conducted at a local facility; standard ranges 
from that laboratory must be appended to the results. Results corresponding to the visit 
must be entered into the eCRF. During these circumstances, it may be feasible to only 
collect safety laboratory tests (chemistry, hematology, and coagulation parameters) 
• The patient should attend the study center at least once every 2 cycles for PET-CT 
assessment of disease status. A PET-CT scan at another center may be acceptable. 
• Study drug required for 2 cycles may be dispensed to the patient. Alternatively, study 
drug may be shipped directly to a patient’s home. 
It is also recommended that any potential new study patient should be screened for COVID-19 
symptoms and asked about travel within the past 21 days or contact with people likely to have 
placed them at risk of infection. If indicated and feasible, potential patients should be tested for 
the virus. Patients who are considered to be at a high risk of COVID-19 virus infection or to have 
confirmed infection, should not be enrolled per exclusion criterion #15. 

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19. 
LITERATURE REFERENCES 
1.  
Epstein M, Achong B, Barr Y. Virus particles in cultured lymphoblasts from Burkitt’s 
lymphoma. Lancet (London, England). 1964;283(7335):702-703. 
2.  
Thompson MP, Kurzrock R, Thompson MP, Kurzrock R. Epstein-Barr virus and cancer. 
Clin Cancer Res. 2004;10(713):803-821. 
3.  
Saha A, Robertson ES. Epstein-Barr virus-associated B-cell lymphomas: Pathogenesis and 
clinical outcomes. Clin Cancer Res. 2011;17(10):3056-3063. 
4.  
Cai Q, Chen K, Young KH. Epstein–Barr virus-positive T/NK-cell lymphoproliferative 
disorders. Exp Mol Med. 2015;47(1):e133. 
5.  
Kanakry JA, Ambinder RF. EBV-related lymphomas: New approaches to treatment. Curr 
Treat Options Oncol. 2013;14(2):224-236. 
6.  
Lu T-X, Liang J-H, Miao Y, et al. Epstein-Barr virus positive diffuse large B-cell 
lymphoma predict poor outcome, regardless of the age. Sci Rep. 2015;5:12168. 
7.  
Ding M, Gao J, Liu X, et al. Clinicopathological characteristics and prognostic analysis of 
epstein-barr virus-positive lymphoma: A meta-analysis. Int J Clin Exp Med. 
2016;9(6):11429-11438. 
8.  
Friedberg JW, Aster JC. Epidemiology, clinical manifestations, and diagnosis of post-
transplant lymphoproliferative disorders. UpToDate. 2017. 
9.  
Anaissie E. Overview of infections following hematopoietic cell transplantation. 
UpToDate. 2012:1-19. 
10.  
Ghosh SK, Perrine SP, Williams RM, Faller D V. Histone deacetylase inhibitors are 
potent inducers of gene expression in latent EBV and sensitize lymphoma cells to 
nucleoside antiviral agents. Blood. 2012;119(4):1008-1017. 
11.  
Mentzer SJ, Fingeroth J, Reilly JJ, Perrine SP, Faller D V. Arginine butyrate-induced 
susceptibility to ganciclovir in an Epstein-Barr-virus-associated lymphoma. Blood Cells 
Mol Dis. 1998;24(2):114-123. 
12.  
Anisimova A, Prachova K, Roubal J, Vonka V. Effects of n-butyrate and phorbol ester 
(TPA) on induction of Epstein-Barr virus antigens and cell differentiation. Arch Virol. 
1984;81(3-4):223-237. 
13.  
Saemundsen A, Kallin B, Klein G. Effect of n-butyrate on cellular and viral DNA 
synthesis in cells latently infected with Epstein-Barr virus. Virology. 1980;107(2):557-
561. 
14.  
Perrine SP, Hermine O, Small T, et al. A phase 1/2 trial of arginine butyrate and 
ganciclovir in patients with Epstein-Barr virus-associated lymphoid malignancies. Blood. 
2007;109(6):2571-2578. 
15.  
Hull EE, Montgomery MR, Leyva KJ. HDAC Inhibitors as epigenetic regulators of the 
immune system: Impacts on cancer therapy and inflammatory diseases. Biomed Res Int. 
2016;2016(8797206):1-15. 
16.  
Lane AA, Chabner BA. Histone deacetylase inhibitors in cancer therapy. J Clin Oncol. 
2009;27(32):5459-5468. 

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17.  
Mottamal M, Zheng S, Huang TL, Wang G. Histone deacetylase inhibitors in clinical 
studies as templates for new anticancer agents. Molecules. 2015;20(3):3898-3941. 
18.  
Moffat D, Patel S, Day F, et al. Discovery of 2-(6-{[(6-Fluoroquinolin-2-
yl)methyl]amino}bicyclo[3.1.0]hex- 3-yl)- N -hydroxypyrimidine-5-carboxamide (CHR-
3996), a class i selective orally active histone deacetylase inhibitor. J Med Chem. 
2010;53(24):8663-8678. 
19.  
Banerji U, Van Doorn L, Papadatos-Pastos D, et al. A phase I pharmacokinetic and 
pharmacodynamic study of CHR-3996, an oral class I selective histone deacetylase 
inhibitor in refractory solid tumors. Clin Cancer Res. 2012;18(9):2687-2694. 
20.  
Venturi C, Bueno J, Gavalda J, et al. Impact of valganciclovir on Epstein-Barr virus 
polymerase chain reaction in pediatric liver transplantation: preliminary report. Transplant 
Proc. 2009;41(3):1038-1040. 
21.  
Gryder BE, Sodji QH, Oyelere AK. Targeted cancer therapy: giving histone deacetylase 
inhibitors all they need to succeed. Futur Med Chem. 2013;4(4):505-524. 
22.  
Cheson BD, Fisher RI, Barrington SF, et al. Recommendations for Initial Evaluation, 
Staging, and Response Assessment of Hodgkin and Non-Hodgkin Lymphoma: The 
Lugano Classification. J Clin Oncol. 2014;32(27):3059-3067. 
23.  
Younes A, Hilden P, Coiffier B, et al. International Working Group consensus response 
evaluation criteria in lymphoma (RECIL 2017). Ann Oncol  Off J Eur Soc Med Oncol. 
2017;28(7):1436-1447. 
24.  
Coiffier B, Altman A, Pui C-H, Younes A, Cairo MS. Guidelines for the Management of 
Pediatric and Adult Tumor Lysis Syndrome: An Evidence-Based Review. J Clin Oncol. 
2008;26(16):2767-2778. 
25.  
Simon R. Optimal two-stage designs for phase II clinical trials. Control Clin Trials. 
1989;10(1):1-10. 
26.  
Glare P. Clinical predictors of survival in advanced cancer. J Support Oncol. 
2005;3(5):331-339. 
27.  
Casper C, Krantz EM, Corey L, et al. Valganciclovir for suppression of human 
herpesvirus-8 replication: a randomized, double-blind, placebo-controlled, crossover trial. 
J Infect Dis. 2008;198(1):23-30. 
28.  
Cheson BD, Pfistner B, Juweid ME, et al. Revised Response Criteria for Malignant 
Lymphoma. J Clin Oncol. 2007;25(5):579-586. 
29.  
Ivanova A, Qaqish BF, Schell MJ. Continuous toxicity monitoring in phase II trials in 
oncology. Biometrics. 2005;61(2):540-545. 
30.  
European Society of Medical Oncology. Performance Scales: Karnofsky & ECOG Scores. 
Oncology//Pro. 2018. 
31.  
VALCYTE® (valganciclovir) Prescribing Information. Genentech, Inc. 06/2017. 

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APPENDIX 
Table 16: 
Conversions for ECOG and Karnofsky Grades30 
Karnofsky Status 
Karnofsky Grade 
ECOG Grade 
ECOG Status 
Normal, no complaints 
100 
0 
Fully active, able to carry on all pre-
disease performance without 
restriction 
Able to carry on normal 
activities. Minor signs or 
symptoms of disease 
90 
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 
Normal activity with effort 
80 
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 
Care for self. Unable to carry 
on normal activity or to do 
active work 
70 
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 
Requires occasional 
assistance, but able to care for 
most of his needs 
60 
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 
Requires considerable 
assistance and frequent 
medical care 
50 
3 
Capable of only limited self-care, 
confined to bed or chair more than 
50% of waking hours 
Disabled. Requires special 
care and assistance 
40 
3 
Capable of only limited self-care, 
confined to bed or chair more than 
50% of waking hours 
Severely disabled. 
Hospitalization indicated 
though death nonimminent 
30 
4 
Completely disabled. Cannot carry 
on any self-care. Totally confined to 
bed or chair 
Very sick. Hospitalization 
necessary. Active supportive 
treatment necessary 
20 
4 
Completely disabled. Cannot carry 
on any self-care. Totally confined to 
bed or chair 
Moribund 
10 
4 
Completely disabled. Cannot carry 
on any self-care. Totally confined to 
bed or chair 
Dead 
0 
5 
Dead 
Abbreviation: ECOG = Eastern Cooperative Oncology Group 

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Table 17: 
Established and Other Potentially Significant Drug Interactions with 
Ganciclovir* 
Concomitant 
Drug 
Change in the Concentration of 
Ganciclovir or Concomitant Drug 
Increased monitoring 
required 
Clinical 
Comment 
Imipenem-
cilastatin 
Unknown 
If required, only administer as 
inpatient with close 
monitoring for seizure activity 
Risk of 
generalized 
seizures 
Cyclosporine or 
amphotericin B 
Unknown 
Monitor serum creatinine at 
least twice weekly for first 
week, followed by monitoring 
every week thereafter 
Risk of renal 
toxicity 
Mycophenolate 
Mofetil (MMF) 
No change in levels of ganciclovir 
or MMF in patients with normal renal 
function 
Monitor serum creatinine 
and CBC at least twice weekly 
for first week, followed by 
monitoring every week 
thereafter 
Risk for 
hematological 
and renal toxicity 
Other drugs 
associated with 
myelosuppression 
or 
nephrotoxicity1 
Unknown 
Monitor serum creatinine 
and CBC at least twice weekly 
for first week, followed by 
monitoring every week 
thereafter 
Risk for 
increased 
hematological 
and renal toxicity 
Didanosine 
No change in ganciclovir 
Increased didanosine 
Serum amylase weekly for 
first month on combination, 
monthly thereafter 
Monitor closely 
for didanosine 
toxicity 
(e.g., pancreatitis) 
Probenecid 
Increased ganciclovir 
Monitor CBC at least twice 
weekly for first week, 
followed by monitoring every 
week thereafter 
May require dose 
reduction of 
valganciclovir 
Abbreviation: CBC = complete blood count 
* Adapted from Prescribing information for valganciclovir (Genentech 2017)31 
1  adriamycin, dapsone, doxorubicin, flucytosine, hydroxyurea, pentamidine, tacrolimus, trimethoprim/sulfamethoxazole, 
vinblastine, vincristine, and zidovudine 

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Version: Amendment 5.0 07 January 2021 
 
Confidential - Viracta Therapeutics, Inc. 
Page 61 of 61 
Table 18a: 
Examples of Sensitive Substrates of CYP3A 
Enzyme 
Therapeutic 
CYP3A 
alfentanil, avanafil, buspirone, conivaptan, darifenacin, darunavir, ebastine, everolimus, ibrutinib, 
lomitapide, lovastatin, midazolam, naloxegol, nisoldipine, saquinavir, simvastatin, sirolimus, 
tacrolimus, tipranavir, triazolam, vardenafil, budesonide, dasatinib, dronedarone, eletriptan, 
eplerenone, felodipine, indinavir, lurasidone, maraviroc, quetiapine, sildenafil, ticagrelor, tolvaptan 
Abbreviation: CYP = cytochrome P450 
 
Table 19b: 
Examples of Strong Inhibitors of P-gp and BCRP Transporters 
Enzyme 
Therapeutic 
P-gp 
amiodarone, carvedilol, clarithromycin, dronedarone, itraconazole, lapatinib, lopinavir and ritonavir, 
propafenone, quinidine, ranolazine, ritonavir, saquinavir and ritonavir, telaprevir, tipranavir and 
ritonavir, verapamil 
BCRP 
curcumin, cyclosporine A, eltrombopag 
Abbreviations: BCRP Breast Cancer Resistance Protein = P-gp = P-glycoprotein