A Phase III Multicenter, Randomized, Open Label Study of APR-246 in Combination With Azacitidine Versus Azacitidine Alone for the Treatment of (Tumor Protein) TP53 Mutant Myelodysplastic Syndromes
Phase: PHASE3
Conditions: MDS
Sponsor: Aprea Therapeutics

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A Phase III Multicenter, Randomized, Open Label Study of APR-246 in Combination 
with Azacitidine Versus Azacitidine Alone for the Treatment of TP53 Mutant 
Myelodysplastic Syndromes 
 
 
Protocol No.:  
A18-15331 
IND No.: 
139738 
Principal Investigator: 
David Sallman, MD 
H. Lee Moffitt Cancer Center & Research Institute 
12902 Magnolia Drive 
Tampa, FL  33612  
Telephone: 813-745-1867 
Email: david.sallman@moffitt.org 
 
Sponsor: 
Aprea Therapeutics AB 
Nobels väg 3 
SE-171 65 Solna 
Sweden 
Telephone: +46 (0)8 50884504 
Medical Monitor/CRO: 
Theradex Oncology  
   
4365 Route 1 South, Suite 101 
Princeton, NJ  08540 
Telephone: 609-799-7580 
Version and Date: 
Version 4.0 / 20JUN2019 
Replaces Version: 
3.0 / 08MAY2019 
 
 
 
 
CONFIDENTIAL 
 
This document contains strictly confidential information and cannot be disclosed or used, 
unless authorized in writing by Theradex Oncology and Aprea Therapeutics AB. 

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1. 
I have carefully read this protocol entitled "A Phase III Multicenter, Randomized, 
Open Label Study of APR-246 in Combination with Azacitidine Versus Azacitidine 
Alone for the Treatment of TP53 Mutant Myelodysplastic Syndromes" and agree that 
it contains all the necessary information required to conduct the study.  I agree to 
conduct this study as outlined in the protocol. 
 
2. 
I understand that this study will not be initiated without approval of the appropriate 
Institutional Review Committee/Independent Ethics Committee (IRB/IEC), and that 
all administrative requirements of the governing body of the Institution will be 
complied with fully. 
 
3. 
Informed written consent will be obtained from all participating patients in 
accordance with institutional guidelines, FDA requirements as specified in Title 21 
CFR, Part 50, the European Union Directive 2001/20/EC and its associated Detailed 
Guidances, European Union GCP Directive 2005/28/EC, the ICH Guideline for Good 
Clinical Practice, Section 4.8, and the terms of the Declaration of Helsinki (2013). 
 
4. 
I will enroll patients who meet the protocol criteria for entry. 
 
5. 
I understand that my signature on each completed Case Report Form (CRF) indicates 
that I have carefully reviewed the complete set of CRFs and accept full responsibility 
for the contents thereof. 
 
6. 
I understand that the information presented in this study protocol is confidential, 
and I hereby assure that no information based on the conduct of the study will be 
released without prior consent from the Sponsor unless this requirement is 
superseded by the Food and Drug Administration, a Competent Authority of the 
European Union or another Regulatory Authority. 
Investigator: 
Name:        
____________________________  
Telephone:  
____________________________ 
 
Address:     
____________________________ 
 
         
     
____________________________ 
 
Signature:   
____________________________  
Date:        
____________________________ 
 
 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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TABLE OF CONTENTS 
 
        Page No. 
 
 ............................................................................................. 2 
TABLE OF CONTENTS .......................................................................................................... 3 
CLINICAL STUDY SYNOPSIS ................................................................................................ 7 
LIST OF ABBREVIATIONS ................................................................................................... 15 
1.0 
GENERAL INFORMATION .................................................................................... 18 
1.1 Protocol Number and Title of the Study .................................................................. 18 
1.2 Sponsor ......................................................................................................................... 18 
1.3 Monitor/CRO ................................................................................................................ 18 
1.4 Signature Authorization .............................................................................................. 18 
1.5 Investigators and Institutions .................................................................................... 18 
2.0 
BACKGROUND INFORMATION ........................................................................... 19 
2.1 MDS................................................................................................................................ 19 
2.2 TP53 Mutated MDS ...................................................................................................... 20 
2.3 The Investigational Product ....................................................................................... 22 
2.4 Azacitidine ..................................................................................................................... 22 
2.5 APR-246 Preclinical Studies ........................................................................................ 23 
2.5.1 Pharmacology and Mode of Action .............................................................. 23 
2.5.2 Safety Pharmacology ...................................................................................... 24 
2.5.3 Pharmacokinetics and Metabolism in Animals .......................................... 25 
2.5.4 Toxicology ........................................................................................................ 25 
2.6 APR-246 Clinical Studies ............................................................................................. 27 
2.6.1 Phase Ib/II MDS (Moffitt) Trial ....................................................................... 28 
2.6.2 Ongoing Phase I/II in TP53 Mutated Advanced Ovarian Cancer.............. 28 
2.6.3 Completed Study APR-246-01: First in Human APR-246 in Solid and 
Hematological Malignancies ...................................................................................... 29 
2.6.4 Completed Phase I/Ib Study APR-246-01 (Amendment 6) ........................ 29 
2.6.5 APR-246 CNS Safety Overview ...................................................................... 30 
2.6.6 APR-246 Cardiac Safety Overview ................................................................ 32 
2.7 Dose Rationale for APR-246 in Combination with Azacitidine .............................. 35 
2.7.1 Rationale for Fixed APR-246 Dosing ............................................................. 35 
2.8 Potential Risks and Benefits ....................................................................................... 36 
2.8.1 Potential Risks ................................................................................................. 36 
2.8.2 Potential Benefits ............................................................................................ 37 
2.9 Characteristics of a Well-Conducted Trial ................................................................ 37 
2.10 Patient Population ....................................................................................................... 37 
3.0 
TRIAL OBJECTIVES AND PURPOSE ...................................................................... 38 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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3.1 Primary Objectives ...................................................................................................... 38 
3.2 Secondary Objectives .................................................................................................. 38 
3.3 Exploratory Objectives ................................................................................................ 38 
4.0 
TRIAL DESIGN ....................................................................................................... 39 
4.1 Overview of Trial Design ............................................................................................. 39 
4.2 End of Study ................................................................................................................. 39 
4.3 Minimizing Bias ............................................................................................................ 39 
4.4 Drug Products .............................................................................................................. 40 
4.4.1 APR-246 ............................................................................................................ 40 
4.4.2 Azacitidine ........................................................................................................ 40 
4.5 Duration of Therapy .................................................................................................... 40 
4.6 Trial Discontinuation ................................................................................................... 40 
4.7 Post-Treatment/Long-Term Follow-up ..................................................................... 41 
4.8 Investigational Drug Procurement/Drug Accountability/Disposition of Clinical Trial 
Supplies .................................................................................................................................. 41 
4.9 Registration and Randomization ............................................................................... 41 
5.0 
SELECTION AND WITHDRAWAL OF SUBJECTS ................................................... 43 
5.1 Inclusion Criteria .......................................................................................................... 43 
5.2 Exclusion Criteria ......................................................................................................... 44 
5.3 Inclusion of Women, Minorities and Children ......................................................... 44 
5.4 Withdrawal Criteria...................................................................................................... 45 
5.4.1 Withdrawn Subjects ........................................................................................ 45 
5.5 Noncompliance ............................................................................................................ 45 
6.0 
TREATMENT OF SUBJECTS ................................................................................... 46 
6.1 Drug Preparation and Administration ...................................................................... 46 
6.1.1 Experimental Arm (APR-246 + Azacitidine) ................................................. 46 
6.1.2 Control Arm (Azacitidine Only) ...................................................................... 47 
6.2 Criteria for Treatment, Retreatment and Dose Modifications .............................. 47 
6.2.1 APR-246 ............................................................................................................ 47 
6.2.2 Management of CNS Adverse Events .......................................................... 53 
6.2.3 Management of Nausea and Vomiting ........................................................ 54 
6.2.4 Management of Infusion Reactions ............................................................. 55 
6.2.5 Azacitidine Dose Adjustments ...................................................................... 55 
6.3 Concomitant Treatment ............................................................................................. 55 
6.4 Monitoring Subject Compliance ................................................................................ 56 
7.0 
STUDY EVALUATIONS .......................................................................................... 57 
7.1 Schedule of Study Evaluations ................................................................................... 57 
7.2 Pre-Study Assessments (All Patients)........................................................................ 60 
7.2.1 Screening (All patients) .................................................................................. 60 
7.2.2 Randomization ................................................................................................ 61 
7.3 Experimental Arm (APR-246 + Azacitidine) .............................................................. 61 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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7.3.1 Cycle 1............................................................................................................... 61 
7.3.2 Cycle 2 Day 1 ± 3 Day (same as Cycle 1 Day 29) ......................................... 62 
7.3.3 Cycle 3 Day 1 ±3 Day (same as Cycle 2 Day 29) and Onwards (Cycle 4+)64 
7.3.4 End of Odd Numbered Cycles Up to Month 12 .......................................... 65 
7.3.5 End of Even Numbered Cycles Up to and Including Month 12 ................ 65 
7.3.6 After Month 12 ................................................................................................ 65 
7.4 Control Arm (azacitidine) ............................................................................................ 65 
7.4.1 Each Cycle Day 1 ±3 Days (same as Day 29 of previous cycle) through Day 
10 
66 
7.4.2 Perform Weekly ............................................................................................... 66 
7.4.3 End of Odd Numbered Cycles Up to Month 12 .......................................... 66 
7.4.4 End of Even Numbered Cycles Up to and Including Month 12 ................ 66 
7.4.5 After Month 12 ................................................................................................ 67 
7.5 End of Treatment Visit (All Patients) ......................................................................... 67 
7.6 Long-Term Follow-Up .................................................................................................. 67 
8.0 
STUDY ASSESSMENTS .......................................................................................... 69 
8.1 Safety Assessments ..................................................................................................... 69 
8.1.1 Safety Analysis ................................................................................................. 69 
8.1.2 Reporting of Adverse Events ......................................................................... 69 
8.1.3 Independent Data Monitoring Committee (IDMC) .................................... 72 
8.2 Efficacy Assessments .................................................................................................. 73 
8.2.1 Duration of Response .................................................................................... 73 
8.2.2 Overall Survival ............................................................................................... 73 
8.2.3 Stem Cell Transplant ...................................................................................... 73 
8.3 Pharmacokinetics ........................................................................................................ 74 
8.4 ECG in Experimental Arm: ECG for APR-246 ............................................................ 75 
8.5 TP53 Testing ................................................................................................................. 75 
9.0 
STATISTICS ............................................................................................................ 76 
9.1 Sample Size ................................................................................................................... 76 
9.2 Analysis Populations ................................................................................................... 76 
9.3 Statistical Methods ...................................................................................................... 76 
9.3.1 Efficacy Analyses ............................................................................................. 76 
9.3.2 Exploratory Analyses ...................................................................................... 77 
9.3.3 Safety Analysis ................................................................................................. 77 
9.3.4 Pharmacokinetic Analysis .............................................................................. 78 
10.0 
QUALITY CONTROL AND QUALITY ASSURANCE PROCEDURES ....................... 79 
10.1 Monitoring of the Study and Regulatory Compliance ............................................ 79 
10.2 Curricula Vitae and Financial Disclosure of Investigators...................................... 79 
10.3 Protocol Modifications ................................................................................................ 79 
10.4 Publication Policy ......................................................................................................... 79 
11.0 
ETHICAL CONSIDERATIONS ................................................................................ 80 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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11.1 Informed Consent........................................................................................................ 80 
11.2 Institutional Review Board/Independent Ethics Committee (IRB/IEC) ................. 80 
11.3 Patient Privacy .............................................................................................................. 80 
12.0 
DATA HANDLING AND RECORD KEEPING ......................................................... 81 
12.1 Data to be Entered Directly in the CRF ..................................................................... 81 
12.2 Recording of Data ........................................................................................................ 81 
12.3 Study Records .............................................................................................................. 81 
13.0 
REFERENCES ......................................................................................................... 82 
APPENDIX I  ECOG PERFORMANCE STATUS .................................................................. 86 
APPENDIX II  PROPOSED MODIFIED INTERNATIONAL WORKING GROUP RESPONSE 
CRITERIA FOR ALTERING NATURAL HISTORY OF MDS .................................................. 87 
APPENDIX III  NEW YORK HEART ASSOCIATION (NYHA) CLASSIFICATION ................ 91 
APPENDIX IV  COCKCROFT GAULT EQUATION............................................................. 92 
 
List of Tables 
Table 1. Outcomes of Patients with AML and MDS Treated with HMA in Four Studies, 
According to TP53 Mutation Status ................................................................................................ 21 
Table 2. Overview of Clinical Studies with APR-246. ................................................................... 27 
Table 3. CNS Related Adverse Events in Clinical Studies (Number of Patients) ..................... 31 
Table 4. ECG Requirements in Experimental Arm ....................................................................... 48 
Table 5. APR-246 Dose Levels ......................................................................................................... 49 
Table 6. Recommendations for APR-246 Dose Modifications and Criteria for Treatment 
Interruption and Re-Initiation with Treatment-Related Adverse Events .................................. 51 
Table 7. Medications for Managements of Nausea and Vomiting ............................................ 55 
Table 8. Schedule of Study Evaluations (also described in Sections 7.2 through 7.5) ........... 57 
Table 9. Sparse PK Blood Sampling Time Points for APR-246 (first 3 cycles) and azacitidine 
(first cycle only) ................................................................................................................................. 74 
Table 10. ECG Requirements in Experimental Arm ..................................................................... 75 
 
List of Figures 
Figure 1. Historical Overall Survival for TP53 
Frontline Azacitidine (Source: Moffitt Cancer Center Database). .............................................. 22 
Figure 2. Structure of APR-246 ....................................................................................................... 22 
Figure 3. Concentration-response analysis for change in QTcF from baseline vs. APR-246 
concentration. ................................................................................................................................... 34 
Figure 4. Drug Administration Schema for Experimental Arm: APR-246 and Azacitidine ..... 46 
Figure 5. Drug Administration Schema for Control Arm: Azacitidine Only .............................. 47 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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CLINICAL STUDY SYNOPSIS 
Title 
A Phase III Multicenter, Randomized, Open Label Study of APR-246 in Combination 
with Azacitidine Versus Azacitidine Alone for the Treatment of TP53 Mutant 
Myelodysplastic Syndromes 
Sponsor 
Aprea Therapeutics AB 
Monitor/CRO 
Theradex Oncology 
Lead 
Investigator 
David Sallman, MD 
H. Lee Moffitt Cancer Center & Research Institute 
Number of 
Study Centers 
Multicenter  
 
Clinical Phase 
III 
Investigational 
Agent 
APR-246 
Study Design 
This study will be a multi-center, open-label, randomized, controlled Phase III trial 
to compare the efficacy of APR-246 in combination with azacitidine versus 
azacitidine alone for the treatment of TP53 mutant myelodysplastic syndromes.  
 
Patients will be randomized (1:1) to one of two treatment arms and stratified by age 
(< 
 65): 
1) Experimental arm: APR-246 + azacitidine; or 
2) Control arm: Azacitidine 
 
The Intent-to-Treat (ITT) population will be the primary analysis population for 
efficacy. All patients who are randomized on study will be considered eligible for 
the ITT population and will be used for demographics, baseline characteristics 
summaries. 
 
Patients may continue treatment as long as toxicity remains acceptable, 
progression has not occurred and the patient has not withdrawn consent. 
Response and progressive disease will be assessed based on the Guidelines for 
Implementation of International Working Group (IWG) response criteria after every 
two treatment cycles the first year, then every three cycles. Patients may remain on 
protocol therapy after relapse or progression if they are continuing to derive clinical 
benefit in the opinion of the Investigator. 
 
Investigators may choose to transition patients towards a stem cell transplantation 
(SCT) as appropriate after a response by the experimental or control treatment has 
been achieved. Patients who undergo SCT will be removed from study treatment 
and will be followed per the study calendar. 
Study 
Objectives 
Primary Objective: 
1. To compare the complete response rate, defined as the proportion of 
patients who achieve complete remission (CR), and duration of CR with 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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APR-246 + azacitidine treatment vs. azacitidine only. 
Secondary Objectives: To measure the following with APR-246 + azacitidine 
treatment vs. azacitidine alone: 
1. Overall response rate (ORR) 
2. Duration of response (DOR) 
3. Rate and time to acute myeloid leukemia (AML) transformation 
4. Overall survival (OS)  
5. Relapse-free survival (RFS) 
6. Transition rate to hematopoietic stem cell transplant (HSCT) 
7. Safety profile 
8. Rate of red blood cell (RBC) and/or platelet transfusion independence (TI)
for 56 days (8 weeks) 
9. Pharmacokinetics of APR-246 and azacitidine  
Exploratory Objectives: 
1. Determine if biomarkers predictive for response to therapy can be derived 
from baseline molecular analyses of bone marrow or blood samples 
2. Determine the depth of remission by IHC, PCR, and other techniques in 
serial bone marrow or blood samples 
3. Investigate potential resistance mechanisms by molecular analysis of bone 
marrow or blood samples at disease progression    
VAF 
Study 
Endpoints 
Primary Endpoint: CR per the modified IWG (Cheson et al, 2006)1 and time between 
achieving CR and relapse of disease. 
Secondary Endpoints: 
1. ORR is the proportion of patients achieving hematological improvement 
(HI), partial remission (PR), CR, marrow CR by the IWG 2006 criteria 
2. Response duration 
3. AML transformation according to World Health Organization (WHO) criteria 
4. OS 
5. RFS 
6. Proportion of patients who transition to HSCT 
7. Safety endpoints can relate to adverse events, serious adverse events, dose 
adjustments or dose holds, lab parameter values, vital signs, ECGs 
8. Patients who achieve RBC and/or platelet TI during the 56-day (8 week) 
period after randomization 
9. Pharmacokinetic endpoints: Cmax (maximum concentration), AUC (area 
under the curve), Vd and clearance (CL) of APR-246 and azacitidine 
Exploratory Endpoints: 
1. Baseline molecular analyses may include, but are not limited to: TP53 VAF 
by NGS, p53 immunohistochemistry, mutations in other genes by NGS, RNA 
expression 
2. Investigations of depth of remission may include, but are not limited to: PCR
and p53 immunohistochemistry 
3. Molecular analyses at disease progression may include, but are not limited 
to: TP53 VAF by NGS, p53 immunohistochemistry, mutations in other genes 
by NGS, RNA expression  

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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Eligibility 
Criteria 
Inclusion Criteria: 
1. Patient has signed the Informed Consent (ICF) and is able to comply with 
protocol requirements 
2. Documented diagnosis of MDS, according to WHO classification (<20%
blasts), that meets IPSS-R classification of intermediate, high, or very 
high-risk disease  
3. Patient has adequate organ function as defined by the following laboratory 
values: 
a) Creatinine clearance > 30 mL/min (by Cockcroft-Gault method; see
Appendix IV) 
b) Total serum bilirubin < 1.5 × ULN unless due to 
 Syndrome, 
underlying disease of MDS, hemolysis or considered an effect of regular 
blood transfusions 
c) Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) < 2.5 
× ULN, unless due to underlying disease of MDS 
4. 
 (ICF)  
5. Having at least one TP53 mutation which is not benign or likely benign 
6. Eastern Cooperative Oncology Group (ECOG) performance status score of 0, 
1, or 2  
7. Females of childbearing potential: negative pre-treatment urine or serum 
pregnancy test 
8. Females of childbearing potential and males with female partners of 
childbearing potential must be willing to use an effective form of 
contraception such as latex condom, hormonal birth control, intrauterine 
device or double barrier method during chemotherapy treatment and for at 
least six months thereafter 
 
Exclusion Criteria: 
1. Patient has a known history of HIV or active hepatitis B or active hepatitis C 
infection (testing not mandatory). 
2. Patient has any of the following cardiac abnormalities (as determined by 
treating MD): 
a) Myocardial infarction within six months prior to registration, 
b) New York Heart Association Class III or IV heart failure (see Appendix III) or 
known left ventricular ejection fraction (LVEF) < 40%, as assessed by 
echocardiogram or MUGA scan; 
c) A history of familial long QT syndrome, 
d) Symptomatic 
atrial 
or 
ventricular 
arrhythmias 
not 
controlled 
by 
medications, 
e) 
470 
correction (QTcF = QT/RR0.33). Note: Patients with QTcF 
470 msec and with 
bundle branch block and/or pacemaker rhythm may be enrolled after 
approval by Medical Monitor. 
3. Concomitant malignancies or previous malignancies with less than a 1-year 
disease free interval at the time of signing consent. Patients with 
adequately resected basal or squamous cell carcinoma of the skin, or 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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adequately resected carcinoma in situ (e.g. cervix) may enroll irrespective of 
the time of diagnosis. 
4. Prior exposure to azacitidine, decitabine or investigational hypomethylating 
agent or induction chemotherapy for MDS or AML. Note: intensive 
chemotherapy for any other prior cancer is not exclusionary. 
5. Use of cytotoxic chemotherapeutic agents, or experimental agents (agents 
that are not commercially available) for the treatment of MDS within 14 
days of the first day of study drug treatment. 
6. Concurrent use of erythroid stimulating agents, G-CSF, or GM-CSF within 14 
days of the first day of study drug treatment.  
7. History of allogeneic stem cell transplantation 
8. Pregnancy: Pregnant women are excluded from this study because APR-246 
has not been studied in pregnant patients. Because there is an unknown 
but potential risk for adverse events in nursing infants secondary to 
treatment of the mother with APR-246, breastfeeding should be 
discontinued if the mother is treated with APR-246.  
9. Active uncontrolled infection. 
Treatment 
plan 
Treatment will be administered on an outpatient basis. No investigational or 
commercial agents or therapies other than those described below may be 
administered with the intent to treat the patient's disease.  
Patients will be randomized (1:1) to 1 of 2 arms and stratified by age (<65 versus 
: 
1) Experimental: APR-246 + azacitidine; or 
2) Control: azacitidine only 
Treatment Schedule for Experimental Arm: APR-246 + Azacitidine  
 
 
APR-246 will be administered as a 6-hour intravenous (IV) infusion daily on days 1-4 
of each 28-day cycle. APR-246 fixed dose is 4.5 g. One dose level reduction to 4.0 g 
is permitted. A second dose reduction could be permitted following discussion with 
the Sponsor and Medical Monitor. 
Azacitidine will be given at the standard dose of 75 mg/m2 over 7 consecutive days
(Days 4-10) as a subcutaneous injection or IV infusion, every 28 days. 
Control arm: Azacitidine (75 mg/m2) only, on Days 4-10, as a subcutaneous injection 
or IV infusion, every 28 days.  
Dose delay / 
modifications 
Dose delays/modifications are permitted per protocol. A single missed dose may be 
compensated by adding an additional dosing day for azacitidine, so that the patient 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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receives the total 7 days of treatment per cycle (see Section 6.2.1).  
Duration of 
Treatment 
The projected Phase III duration is 30 36 months. Patients may continue treatment 
to the end of the trial while deriving clinical benefit, unless unacceptable toxicity, 
progression, death or patient withdrawal requires discontinuation. Patients may 
remain on protocol therapy after relapse or progression if they are continuing to 
derive clinical benefit in the opinion of the Investigator. 
Duration of 
Follow-Up  
 
Assuming there is no withdrawal of consent, patients who stop study treatment 
(APR-246 or azacitidine) for any reason (e.g. toxicity, transition to SCT, PD) will 
continue long term follow-up: 
1. Patients who discontinue study treatment to receive SCT: 
a.  Collect post SCT response assessments, transformation to AML and 
survival every month until relapse or death, whichever occurs first.  
b. After PD, collect data for survival and transformation to AML every 6 
months until death. 
2. Responders (CR, PR, mCR with HI, mCR without HI, HI) who discontinue study 
treatment for other reasons than progressive disease or SCT: 
a. Collect response assessments, transformation to AML and survival 
every month until relapse or death, whichever occurs first. 
b. After relapse/progression, continue collecting data for survival and 
transformation to AML every 6 months until death. 
3. Non-Responders: patients who discontinue study treatment due to progressive 
disease:  
a. Collect data for survival and transformation to AML every 6 months 
until death. 
If a patient is removed from the study treatment due to unacceptable adverse 
events, the event(s) will be followed until resolution or stabilization. 
Criteria for Removal from Study 
Study drug treatment can continue for patients receiving clinical benefit, unless: 
study is terminated.  
1. Patient Completion 
A patient will be considered to have completed the study if the patient meets at 
least 1 of the following criteria: 
 
The patient has progressive disease. 
 
The patient died during the study. 
 
The patient experienced a treatment related AE that led to withdrawal from 
the study. 
 
The patient starts new treatment for their underlying disease (MDS). 
2. Patient Withdrawal from Study Treatment: 
If the patient is permanently withdrawn from study treatment, but does not 
withdraw consent to be followed on study, the investigator must make every effort 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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to have the patient complete all withdrawal assessments at the time of withdrawal, 
and complete all scheduled follow-up visits. 
3. Patient Withdrawal from Study: 
A patient may voluntarily withdraw from study treatment or withdraw consent from 
the study at any time. The investigator may also, at his or her discretion, 
discontinue a patient from participating in the study at any time. The investigator 
and/or designated staff will record the date and the reason for patient withdrawal 
from the study. 
Study treatment must be discontinued if: 
-   Evidence of disease progression according to IWG 2006 criteria.  
-   A patient becomes pregnant. 
-   A patient is significantly non-compliant with the requirements of the protocol. 
-   A patient has an adverse experience that would, in the I
 
judgment, make continued participation in the study an unacceptable risk. 
-   A patient withdraws consent. 
-   A patient receives HSCT. 
Follow-Up on 
study 
See Schedule of Study Evaluations. 
Statistics 
This study will be a multi-center, open-label, randomized, controlled Phase III trial 
to compare the efficacy of APR-246 in combination with azacitidine versus 
azacitidine alone for the treatment of TP53 mutant MDS.  
Analysis Populations 
 
Intent-to-treat (ITT): All patients who are randomized on study will be considered 
eligible for the ITT population and will be used for demographics, baseline 
characteristics summaries. The ITT population will be the primary analysis 
population for efficacy. 
Efficacy evaluable (EE): All patients who complete at least one treatment cycle of 
APR-246 and azacitidine and who have at least one post-treatment clinical response 
assessment. Patients who fail to complete one treatment cycle will also be 
considered EE if they show clear evidence of clinically significant disease 
progression. The EE population will be the secondary analysis population for 
efficacy. 
Safety population: Patients will be evaluable for safety if they receive at least one 
dose of APR-246 or azacitidine. The safety population will be used to summarize 
exposure and safety parameters. 
Pharmacokinetics (PK): Patients will be evaluable for pharmacokinetics if at least 
one sample for PK evaluation has been obtained. 
Determination of Sample Size 
This trial assumes a sample size of 154 patients with 77 patients randomized in a 
1:1 ratio to one of the two treatment arms (APR-246 + azacitidine treatment versus 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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azacitidine treatment alone). If the true CR rate is 50% for the treatment arm and 
25% for the control arm, the trial will have 90% power to detect a statistically 
significant effect in favor of the APR-246 treatment combination at a 2-sided alpha 
= 0.05 significance level. 
Efficacy Analyses 
Primary endpoint CR will be summarized for all randomized patients (ITT) as the 
proportion of patients (%) with CR. CR will be compared between arms using a 
Cochran-Mantel-Haenszel (CMH) test stratified by age (< 65 years versus 
 65 
years).  In addition to presenting the CR rate and associated exact 95% confidence 
intervals (CI) for each treatment arm, the treatment effect will be described using 
the CMH estimate of the common odds ratio together with its associated 95% CI. 
Duration of response (DOR) is defined as the time from the date when criteria for 
response are met to the date of progressive disease or death due to any cause, 
whichever occurs first. Patients alive with no progressive disease will have their 
DOR censored at the date of the last clinical assessment. The duration of CR will be 
summarized in each treatment arm by providing the median DOR together with 
associated 95% (CI), using Kaplan-Meier methodology.  
Overall response will be summarized in number (%) of patients in each category of 
responses (CR, PR, mCR with HI, mCR without HI, HI). ORR will be analyzed by using 
the similar method as primary endpoint CR. DOR, as defined above, will also be 
evaluated in regard to ORR. Time to AML is calculated from first day of study 
treatment to first onset of AML. Kaplan-Meier methodology will be utilized. Rate of 
AML transformation will be analyzed by using the similar method as primary 
endpoint CR. 
Survival data are collected at treatment and follow-up periods. Patients will be 
followed until death. Overall survival (OS) is defined as the number of days from the 
date of randomization to the date of death. Kaplan-Meier methodology will be 
utilized. 
Relapse-free survival (RFS) is defined as the time from the date of randomization to 
disease relapse or death from MDS, whichever occurs first. If neither event occurs, 
RFS will be censored at the date of the last clinical assessment. Kaplan-Meier 
methodology will be utilized. 
Time to AML, OS and RFS will be analyzed using the similar methods as DOR. 
Transition rate to HSCT will be analyzed using the similar methods as primary 
endpoint CR. 
 
Safety Analyses 
Safety data including adverse events, vital signs, laboratory data, ECG, physical 
exam will be tabulated for the safety population. Adverse events will be tabulated 
by body system, preferred term, severity, and relationship to treatments. The 
tabulation of laboratory parameters will include the normal ranges for each 
parameter.  Each value will be classified as falling above, below, or within the 
normal range. Laboratory parameters will also be tabulated by maximum NCI-

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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CTCAE v5.0 severity grade. 
Pharmacokinetic Analysis 
In Experimental Arm, sparse PK sampling for APR-246 will be done at all sites in 
cycles 1-3, on Days 1, 2 and 4.  
In both Arms, azacitidine PK will be performed at selected sites in cycle 1, on Day 4. 
The pharmacokinetics of APR-246 and azacitidine will be summarized using
descriptive statistics. 
For APR-246, a population PK model will be used to estimate individual Cmax, AUC
and CL for each patient. APR-246 AUC and Cmax will then be tested for association 
with signs of efficacy and safety. If an observable trend exists, a PK/PD model will 
be developed to evaluate the exposure-response relationship between APR-246
plasma exposure and outcome measures. Demographic and clinical data (ethnicity, 
current age, body weight, sex, disease status, etc.) will be utilized to assess 
interpatient variability in the PK and PK/PD relationships. 
For azacitidine non-compartmental methods will be used to derive PK parameters 
(Cmax, Tmax, AUC, V and CL). 
 
 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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LIST OF ABBREVIATIONS 
ALP 
Alkaline Phosphatase 
ALT
Alanine Aminotransferase
AML 
 
Acute Myeloid Leukemia 
ANC 
Absolute Neutrophil Count 
AST 
Aspartate Aminotransferase 
AUC 
Area Under the Curve 
CBC 
Complete Blood Count 
CL
Clearance
CI 
Confidence Interval 
CLL 
Chronic Lymphocytic Leukemia 
Cmax 
Maximum Concentration 
CMH 
Cochran-Mantel-Haenszel 
CMML 
Chronic Myelomonocytic Leukemia 
CNS
Central Nervous System
CR 
Complete Remission 
CRF 
Case Report Form 
CRO 
Contract Research Organization 
CTCAE 
Common Terminology Criteria for Adverse Events 
DAR 
Drug Accountability Record 
ddPCR 
Digital Droplet Polymerase Chain Reaction 
DILI 
Drug-Induced Liver Injury 
DL 
Dose Level 
DLT 
Dose-Limiting Toxicity 
DNA 
Deoxyribonucleic Acid 
DNMT 
DNA Methyltransferase 
DOR 
Duration of Response 
ECG 
Electrocardiogram 
ECOG 
Eastern Cooperative Oncology Group 
EE 
Efficacy Evaluable 
Emax 
Maximal Effect 
EOI 
End of Infusion 
ESA 
Erythropoietic Stimulating Agent 
EU 
European Union 
FAB 
French American British Classification System 
GCP 
Good Clinical Practices 
G-CSF 
Granulocyte-Colony Stimulating Factor 
GLP 
Good Laboratory Practices 
GM-CSF 
Granulocyte Macrophage-Colony Stimulating Factor 
GMP 
Good Manufacturing Practices 
hERG 
Human Ether-a-Go-Go Gene 
HFD 
Highest Feasible Dose 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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Hgb 
 
Hemoglobin 
HGSOC 
High Grade Serous Ovarian Cancer 
HMA 
Hypomethylating Agent 
HI 
Hematologic Improvement 
HIV
Human Immunodeficiency Virus
HPLC 
High Performance Liquid Chromatography 
HR 
Hazard Ratio 
HSCT 
Hematopoietic Stem Cell Transplant 
IB 
Investigator's Brochure 
IEC/IRB 
Independent Ethics Committee/Institutional Review Board 
ICF
Informed Consent Form
IM 
Intramuscular 
IMP 
Investigational Medicinal Product 
IPSS/IPSS-R 
International Prognostic Scoring System/ Revised IPSS 
ITT 
Intent-to-Treat 
IV 
Intravenous 
IWG
International Working Group
IWRS 
Interactive Web Response System 
LBM 
Lean Body Mass 
LFT 
Liver Function Test 
LVEF 
Left Ventricular Ejection Fraction 
mCR 
Marrow Complete Remission 
MDS 
Myelodysplastic Syndrome 
MedDRA 
Medical Dictionary for Regulatory Activities 
MM 
Multiple Myeloma 
MQ 
2-Methylene-Quinuclidin-3-One 
MTD 
Maximum Tolerated Dose 
NCI-CTCAE 
National Cancer Institute  Common Terminology Criteria 
for Adverse Events 
NGS 
Next Generation Sequencing 
NHL 
Non-Hodgkin's Lymphoma 
NOAEL 
No Observed Adverse Effect Level 
ORR 
Overall Response Rate 
OS 
Overall Survival 
PD 
Progressive Disease 
PHL 
Potential Hy's Law 
PI 
Principal Investigator 
PK 
Pharmacokinetics 
PLD 
Pegylated Liposomal Doxorubicin 
PR 
Partial Remission 
RA 
Refractory Anemia 
RAEB 
Refractory Anemia with Excess Blasts 
RAEB-T 
Refractory Anemia with Excess Blasts in Transformation 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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RBC 
Red Blood Cell 
RFS 
Relapse-Free Survival 
ROS 
Reactive Oxygen Species 
SAE 
Serious Adverse Event 
SC
Subcutaneous
SCT 
Stem Cell Transplant 
TEAE 
Treatment Emergent Adverse Event 
TI 
Transfusion Independence 
TID 
Three Times a Day (Ter in Die) 
Tmax 
Time of Maximum Concentration 
TrxR1
Thioredoxin Reductase
ULN 
Upper Limit Normal 
US 
United States 
VAF 
Variant Allele Frequency 
Vd 
Volume of Distribution 
WHO 
World Health Organization 
 
 
 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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1.0  GENERAL INFORMATION 
1.1 
Protocol Number and Title of the Study 
Protocol Number:  A18-15331 
A Phase III Multicenter, Randomized, Open Label Study of APR-246 in Combination with 
Azacitidine Versus Azacitidine Alone for the Treatment of TP53 Mutant Myelodysplastic 
Syndromes 
 
1.2 
Sponsor 
Aprea Therapeutics AB 
Nobels väg 3 
SE-171 65 Solna 
Sweden 
Telephone: +46 (0)8 50884504 
 
1.3 
Monitor/CRO 
Theradex Oncology 
4365 Route 1 South, Suite 101 
Princeton, New Jersey 08540 
Telephone: (609) 799-7580 
 
1.4 
Signature Authorization 
Theradex Oncology will act as the Sponsor Representative. 
 
1.5 
Investigators and Institutions 
Principal Investigator: 
David Sallman, MD 
H. Lee Moffitt Cancer Center & Research Institute 
12902 Magnolia Drive 
Tampa, FL  33612  
Telephone: 813-745-1867 
Email address: david.sallman@moffitt.org  
 
This study will be performed at multiple institutions.   
 
 
 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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2.0 BACKGROUND INFORMATION 
2.1 
MDS    
Myelodysplastic syndrome (MDS) represents a group of clonal hematopoietic stem cell 
disorders predominating in the elderly, characterized by ineffective hematopoiesis leading 
to blood cytopenias. In 2015, the estimated incidence of MDS in the US was 4 cases per 
100,000 persons/year2. This syndrome shows variable clinical courses, from indolent to life-
threatening conditions related to severe cytopenia or progression to acute myeloid 
leukemia (AML). Progression to AML, a diagnosis with very dismal prognosis, occurs in 
approximately 10% and 70% of lower- and higher-risk patients, respectively. MDS 
development is associated with accumulation of cytogenetic changes and/or gene 
mutations. At advanced stages widespread gene hypermethylation is seen, and 
hypomethylating agents (HMAs) azacitidine or decitabine are the cornerstone treatment.  
The overall prognosis is largely based on factors such as the marrow blast percentage, 
number and extent of cytopenias and cytogenetic abnormalities, which are grouped in a 
recently revised International Prognostic Scoring System (IPSS/IPSS-R)3. Although the 
to IPSS high or intermediate-
ermediate-
1)4, and this separation is often the base for treatment recommendations. 
Current treatment options for patients with higher risk MDS include chemotherapy, HMAs, 
and allogeneic hematopoietic stem cell transplantation (allo-HSCT, which is the only 
potentially curative treatment, but limited by morbidity in the patient population)5. The 
following agents have been approved for the treatment of MDS by the US Food and Drug 
Administration: 
 
Azacitidine: May 2004, for both low- and high-risk patients with all sub-types of MDS, 
including refractory anemia with excess blasts in transformation (RAEB-T; now 
defined as AML with 20-30% blasts) 
 
Lenalidomide: December 2005, or transfusion-dependent MDS patients with 
isolated del(5q) and with a low or intermediate-1 risk IPSS score 
 
Decitabine: May 2006, same indication as azacitidine 
AML-like intensive chemotherapy has limited indication in higher risk MDS patients. In 
particular, patients with unfavorable karyotype show few complete remissions/responses 
(CRs) and shorter CR duration6. Low-dose cytarabine was found to be significantly inferior 
to azacitidine (in terms of response and survival) in a randomized Phase III study7, 
especially in patients with unfavorable cytogenetics. However, low-dose cytarabine may still 
be a treatment option in higher risk MDS patients with normal karyotype8 who are not 
candidates for any intensive chemotherapy or allo-SCT, in particular when administration 
of azacitidine or decitabine is not possible4. Recent analyses also support the prognostic 
and predictive value of TP53 mutations in MDS patients treated with HMAs (Section 2.2). 
 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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2.2 
TP53 Mutated MDS 
The advent of next generation sequencing (NGS) has provided a rapid and efficient 
platform for genome studies that has revolutionized the diagnostic, prognostic, and 
therapeutic realms of myeloid malignancies9. Current NGS myeloid panels incorporate 
20-50 genes and can identify mutations in the vast majority of patients10,11. In MDS, 
mutations of ASXL1, ETV6, EZH2, RUNX1 and TP53 were found to be independently 
associated with decreased survival12. Of these, recent investigations have suggested that 
the mutational status of TP53 is the most important negative prognostic factor in MDS 
patients. To date, the only disease modifying agents in MDS include lenalidomide in 
patients with isolated deletion of 5q (del(5q)) and azacitidine (a DNA methyltransferase 
(DNMT) inhibitor/HMA) in MDS patients with higher risk disease (i.e., intermediate 2/high 
risk by IPSS and high/very-high by IPSS-R). Lenalidomide was approved based on the 
MDS-003 trial with 67% of del (5q) patients achieving transfusion independence and 45% of 
patients with complete cytogenetic response13. However, primary resistance to 
lenalidomide has been directly linked to TP53 mutation which occurs in 20% of patients14. 
Whereas partial cytogenetic responses occur in up to 73% of patients, TP53 mutated del(5q) 
patients only have cytogenetic responses in 0-11% of cases15,16,17. For higher risk MDS 
patients, azacitidine represents the standard of care based on the AZA-001 trial that 
demonstrated a survival advantage for azacitidine when compared with induction 
chemotherapy, low dose cytarabine, or best supportive care (24.5 months versus 
15 months, p<0.0001)18. A recent study in MDS showed strong association of TP53 mutation 
with poor outcome in azacitidine treated patients19. In addition, Bejar and colleagues 
recently confirmed decreased OS in TP53 mutated MDS patients treated with HMA without 
effect on response rates20. Lastly, mutations of TP53 strongly predict for lack of benefit to 
allogeneic bone marrow transplantation, which represents the only curative option for 
patients with MDS21. This study highlights the prognostic importance of TP53 mutations as 
patients with complex karyotype without TP53 mutation had similar survival to patients 
with normal karyotype.   
As shown in Table 1, a range of ORR and CR rates within recent years, specifically among 
TP53 mutant MDS/AML patients treated with HMA, has been reported. Bally and colleagues 
reported 22% CR (Takahashi reported as high as 34% but that combined CR among 
different regimens). Sallman et al. (Moffitt Cancer Center) performed an internal analysis 
(see below) and reported 19% CR. Therefore, a conservative historical rate on the usage of 
standard azacitidine regimen would be approximately 20%.   

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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Table 1. Outcomes of Patients with AML and MDS Treated with HMA in Four Studies, 
According to TP53 Mutation Status 
Study 
No. 
of pa-
tients
Patients 
with 
Muta-
ted TP53
Overall Response 
Complete Response 
Overall Survival 
Mutated 
TP53 
Wild-
Type 
TP53 
P 
Value 
Mutated 
TP53 
Wild-
Type 
TP53 
P 
Value 
Mutated 
TP53 
Wild-
Type 
TP53 
P 
Value 
Bally et 
al.  
62  
(44 
MDS) 
23 (37) 
10 (43) 
20 (51) 
0.60 
5 (22) 
15 (38) 
0.26 
Median of 
12.4 mo 
Median 
of 23.7 
mo 
< 
0.001 
Bejar et 
al.  
213 
MDS 
39 (18) 
20 (51) 
80 (46) 
NS 
NA 
NA 
NA 
Hazard 
ratio for 
death, 
2.01 (95% 
CI, 1.29-
3.14) 
 
0.002 
Takahashi 
et al.  
168 
MDS 
38 (23) 
15 (39) 
41 (32) 
0.13 
13 (34) 
35 (27) 
0.38 
Median of 
9.4 mo 
Median 
of 20.7 
mo 
< 
0.001 
Jung et al. 
107 
MDS 
13 (12) 
10 (77) 
47 (50) 
0.88 
NA 
NA 
NA 
31% at 2 
yr. 
67% at 2 
yr. 
0.003 
 
In the study by Bally et al., the regimen for all the patients was 75 mg of azacitidine per square meter of body-surface area per day for 7 days. 
The median duration of response was 7 months among patients with mutated TP53 and 8 months among those with wild-type TP53 (P=0.38).  
In the study by Bejar A al., 42 patients (20%) received azacitidine, 144 (68%) received decitabine, and 27 (13%) received decitabine plus another 
medication.  
In the study by Takahashi A et al., 38 patients (23%) received azacitidine at a dose of 75 mg per square meter per day for 5 to 7 days, 40 (24%) 
received 20 mg of decitabine per square meter per day for 5 days, 79 (47%) received azacitidine or decitabine plus another medication, and 11 
(7%) received 60 mg of guadecitabine per square meter per day for 5 days. The median duration of response was 5.7 months among patients 
with mutated TP53 and 28.5 months among those with wild-type TP53 (P=0.003).  
¶ In the study by Jung et al., 66 patients (62%) received azacitidine and 41 (38%) received decitabine.  
Source: N Engl J Med 2017; 376:796-798 22 
 
Sallman et al. performed an internal analysis of molecularly profiled patients at Moffitt 
Cancer Center and also identified that the clonal burden, or variant allele frequency (VAF), 
had significant impact on clinical phenotype and more importantly further stratified 
prognosis over binary mutational analysis alone and/or clinical prognostic models23. 
Specifically, MDS patients with a TP53 VAF > 40% had a median overall survival (OS) of 124 
days versus an OS that was not reached in patients with VAF < 20% (hazard ratio (HR), 3.52; 
P = 0.01) with validation in an independent cohort (HR, 4.94, P = 0.01). Overall, TP53 mutant 
MDS and AML patients have a median OS ranging from 5-9 months with 8 months 
representing the best estimate when restricting to MDS and oligoblastic AML (20-30% 
blasts) (Figure 1) 20,23.24;25,26.  

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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Figure 1. Historical Overall Survival for TP53 
with Frontline Azacitidine (Source: Moffitt Cancer Center Database). 
Median OS of 7.6 Months in MDS/AML patients treated with frontline AZA (n=51). 
Together, these data highlight the dismal outcomes of TP53 mutant patients and the dire 
need for the development of novel therapeutic strategies, particularly in this patient 
population. 
 
2.3 
The Investigational Product  
APR-246, 2-hydroxymethyl-2-methoxymethyl-1-azabicyclo [2,2,2] octan-3-one is also called 
PRIMA-1Met in the literature, where PRIMA is an acronym for p53 reactivation and induction 
of massive apoptosis (see IB). 
 
The APR-246 compound has a molecular weight of 199.24 g/mol, is a racemic mixture and 
is isolated as a white powder. The structure of APR-246 can be seen in Figure 2 below.  
 
Figure 2. Structure of APR-246 
 
 
2.4 
Azacitidine 
Azacitidine is a nucleoside metabolic inhibitor indicated by the U.S. FDA for the treatment 
of patients with the following French-American-British (FAB) MDS subtypes: refractory 
anemia (RA) or refractory anemia with ringed sideroblasts (if accompanied by neutropenia 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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or thrombocytopenia or requiring transfusions), refractory anemia with excess blasts 
(RAEB), refractory anemia with excess blasts in transformation (RAEB-T), and chronic 
myelomonocytic leukemia (CMML). The recommended starting dose for the first treatment 
cycle, for all patients regardless of baseline hematology laboratory values, is 75 mg/m2 
subcutaneously or intravenously, daily for 7 days. Patients are to be premedicated for 
nausea and vomiting. Repeat cycles every 28 days. Treatment may be continued as long as 
the patient continues to benefit.   
 
Azacitidine is rapidly absorbed after subcutaneous or IV administration with a Vd of 76 ± 26 
L and a half-life of 41 ± 8 minutes. Cmax is reached after about 30 minutes. Azacitidine and 
its metabolites are known to be substantially excreted by the kidney, and the risk of 
adverse reactions to this drug may be greater in patients with impaired renal function. 
Urinary excretion is the primary route of elimination; the cumulated urinary excretion is 
85% of radioactive dose with less than 1% recovered in feces over 3 days. 
 
Azacitidine undergoes spontaneous hydrolysis in aqueous solution and is deaminated by 
cytidine deamidases, whereas APR-246 is glucuronidated. Although both compounds and 
their degradation products and metabolites are primarily eliminated by urinary excretion 
drug-drug interaction is not likely, but will be investigated as part of the current trial.  
 
2.5 
APR-246 Preclinical Studies 
2.5.1 Pharmacology and Mode of Action 
APR-246 is a novel small molecule anti-cancer compound that reactivates non-functional 
p53 and targets the cellular redox balance, resulting in induction of apoptosis in tumor 
cells. APR-246 is sometimes denoted PRIMA-1Met in the literature. 
 
APR-246 is a chemically synthesized prodrug, which spontaneously decays into the active 
moiety MQ (2-methylene-quinuclidin-3-one) that binds covalently to cysteines in mutant 
p53. Transfer of MQ-modified mutant p53 protein into tumor cells lacking p53 induced 
massive apoptosis, indicating that covalent binding of MQ per se is sufficient to activate 
mutant p53 and induce a p53 dependent biological response. These and other 
experiments directly looking at the conformational state of p53 protein have confirmed 
that binding of MQ pushes unfolded mutant or wild type p53 towards a functional wild type 
conformation.  
 
M
Two 
other cellular targets that have been identified are thioredoxin reductase 1 (TrxR1) and 
glutathione. TrxR1 was identified as a target of MQ, potentially contributing to the anti-
cancer effect. MQ converts this enzyme from a reductase to an oxidase that can produce 
reactive oxygen species (ROS). Inhibition of TrxR1 has also been shown to cause 
endoplasmic reticulum stress, which is one observed effect of APR-246 treatment. Further 

Aprea Therapeutics AB  
Protocol Number A18-15331 
Phase III Randomized Trial of APR-246 and Azacitidine Versus 
Azacitidine Alone in TP53-mutated MDS
 
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in vitro experiments have shown that MQ also readily reacts with glutathione, a central 
molecule in the cellular redox system. Thus, APR-246 via MQ has effects that lead to 
, including depletion of 
glutathione. The enhanced oxidative stress in tumor cells pushes the redox system to the 
limit of its capacity, compared with normal cells, making the redox system an Achilles' heel 
of tumor cells, which may be utilized to selectively kill tumor cells. 
 
APR-246 has been investigated for potency and efficacy in various in vitro, ex vivo, and in 
vivo cancer models, both as single substance and in combination with different 
conventional chemotherapeutics. In many of these models APR-246 has shown good 
potency and efficacy and unique pharmacological profile in comparison with conventional 
chemotherapeutic drugs. The effect of combination treatment with APR-246 and 
azacitidine in MDS cells has been investigated in preclinical models. A synergistic effect was 
shown with an MDS cell line carrying a TP53 mutation. In a colony growth assay with 
primary MDS cells there was a significantly larger effect of combination treatment than 
azacitidine alone, particularly in TP53-mutated patients. In a xenograft model, treatment 
resulted in a significant inhibition of tumor growth.  
 
In conclusion, the preclinical results show that in addition to its own apoptotic effect, 
APR-246 acts synergistically with DNA damaging agents and other established anti-cancer 
compounds. This is accordance with the proposed mechanism of action of APR-246, 
activating mutant p53 and increasing the oxidative stress of tumor cells. 
 
2.5.2 Safety Pharmacology 
APR-246 has been investigated for core safety pharmacology endpoints in mice and dogs. 
The compound induced clinical signs indicating adverse reactions on the central nervous 
system (CNS) and the respiratory function, after bolus injection to mice or as short-term 
infusion in dogs. These effects were observed in direct connection with the dosing and 
were transient, with a rapid and full recovery after the end of the infusion or after the 
interruption of a non-tolerated dose at a stage of moderate CNS clinical signs. Irwin and 
rotarod tests in mice indicate that the CNS toxicity is due to the active moiety MQ and not 
to any of the two enantiomers of the prodrug APR-246.   
 
The severity of clinical signs correlated with the plasma levels. Independently of dose, 
infusion rate or infusion time the plasma threshold for inducing CNS adverse reactions was 
at least 100 µg/mL. The infusion rate of 100 mg/kg/h induced no signs related to CNS or 
respiratory function at 200 mg/kg in two independent studies in dogs. Daily infusion for 9 h 
in 3 cycles of 7 days at the rate of 100 mg/kg/h giving a total daily dose of 900 mg/kg/day 
induced no significant adverse reactions related to CNS or respiratory function. There were 
no cardiovascular effects at any dose level in a telemetric study and the human ether-a-go-
go gene (hERG) study was negative up to 100 µM. At the no observed effect level of 200 
mg/kg given as a 30-minute infusion in the cardiovascular study the peak plasma 

Aprea Therapeutics AB  
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Azacitidine Alone in TP53-mutated MDS
 
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concentration was 154 and 130 µg/mL in male and female dogs, respectively. 
 
It was concluded that CNS and respiratory effects induced by APR-246 were concentration 
dependent. No significant toxicity was observed when infusion was prolonged up to 10 h at 
the rate of 100 mg/kg/h (1000 mg/kg/day) reaching plasma concentrations around 120 
µg/mL.   
 
2.5.3 Pharmacokinetics and Metabolism in Animals 
APR-246 is a prodrug which yields the thiol-reactive compound MQ, forming reversible 
covalent bonds. This combination of reactivity and reversibility makes MQ difficult to study 
in biological systems, while the prodrug APR-246 is readily studied. The data demonstrate 
that APR-246 has a low protein binding across species. The terminal plasma half-life was 
about 3 h in mice and 2 to 5 h in dogs. A whole-body quantitative autoradiography study in 
rat using carbon-14 labeled APR-246 showed that the radioactivity was rapidly distributed 
into the whole body and was excreted both into the gastrointestinal tract and urine.  
 
In plasma samples collected from mice, the main APR-246 related molecules were parent 
compound, the two glucuronidated APR-246 enantiomers M3 and M4, and demethylated 
APR-246 (M1). The drug-drug interaction with paracetamol (acetaminophen) has been 
studied, suggesting that preadministration of APR-246 leads to a slight shift in the amount 
of glucuronidated paracetamol metabolites, but also enhance hepatic levels of glutathione 
which is liver protective. Therefore, clinically relevant drug-drug interaction between 
APR-246 and paracetamol appears unlikely. APR-246 is not metabolized by cytochrome 
p450 enzymes. 
 
2.5.4 Toxicology 
APR-246 has been investigated for toxicology in agreement with existing regulatory 
guidelines for clinical trials in patients with malignancies, and the systemic exposure has 
been investigated using a validated bioanalytical method. All pivotal studies were 
conducted in compliance with GLP guidelines. Single dose toxicity, the 4-week repeat dose 
toxicity and 3-month toxicity studies have been investigated after IV treatment, which is the 
clinical route. The treatment was given as a bolus injection in mouse and as bolus injection, 
30-minute infusion or 2-hour, 3-hour, 4.5-hour and 9-hour infusion in dog. In addition, a 
GLP study in dogs designed specifically to investigate the relationship between plasma 
concentrations and adverse CNS effects has been performed. 
 
The studies demonstrated that APR-246 induced transient clinical signs of adverse 
reactions involving CNS and respiratory functions during or immediately after the 
treatments, clearly indicating a direct relationship with plasma concentration. All 
treatment-related deaths occurred early after treatment in connection with severe clinical 
signs of adverse reactions. Treatment-related deaths occurred from 250 mg/kg/day in mice 

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after slow bolus injection, and at 200 mg/kg/day in dogs, when APR-246 was given as a 30-
minute infusion. Hence, the death of 2 dogs in one study was at an infusion rate of 400 
mg/kg/h.  
 
Whereas 200 mg/kg/day given daily as a 30-minute infusion was not tolerated in dog, no 
similar signs were observed after prolongation of the infusion time to 2 h at 200 mg/kg/day 
(hence 100 mg/kg/h), which was defined as the no observed adverse effect level (NOAEL) in 
dog. The maximum tolerated dose (MTD) in the mouse was 150 mg/kg/day, when APR-246 
was given as a slow bolus injection. Toxicokinetic parameters demonstrated dose-
proportionality with no significant gender differences. The systemic exposure declined 
approximately 2-fold between day 1 and day 28 in mice, which might explain the decline in 
clinical signs with time during the progress of the repeat dose study in mouse. No clear 
time-dependency of effects was observed in the dog in the 4-week study. 
 
Large exposures were achieved in the pivotal 3-month GLP toxicity study, showing that an 
infusion rate of 100 mg/kg/h was well tolerated when given 9 hours per day (900 
mg/kg/day) for 7 days with 21 days recovery in 3 cycles. The clinical signs observed were 
mild and laboratory changes were mild and of doubtful treatment-relationship. The dose of 
900 mg/kg/day given as a 9-hour infusion at the rate of 100 mg/kg/h was defined as the 
NOAEL. In the non-GLP pre-study, no significant signs were observed at this infusion rate 
given daily for 5 days over 10 hours (hence 1000 mg/kg/day). 
 
The data clearly demonstrate that APR-246 induces CNS toxicity in a dose- and rate-
dependent manner. The severity of clinical signs was found to be directly correlated to the 
plasma concentration. With an infusion rate of 400 mg/kg/h during 40 minutes, plasma 
levels around 400 µg/mL were reached without mortality. Based on this carefully 
monitored additional dog study, the CNS toxicity window, from detected mild signs to 
severe signs, was found to be approximately 140 to 400 µg/mL. Independently of dose, 
infusion rate or infusion time the plasma threshold for inducing CNS adverse reactions was 
at least 100 µg/mL. The CNS effects showed reversibility, for example after interruption of 
infusion after 40 minutes at the non-tolerated rate of 400 mg/kg/h, all animals recovered 
and had normal movements from 30 minutes after the infusion, whereas slight tremor and 
hypoactivity lasted longer with full recovery after 3 h. 
 
APR-246 induced no treatment-related changes in laboratory parameters in either the 
mouse or the dog, and there were no findings at ophthalmoscopic examinations or ECG 
investigations. Neither were there any treatment-related gross or histopathological findings 
indicating systemic target organ toxicity observed in any study.  
 
APR-246 was mutagenic in the Ames test. No mutagenicity was observed in the S. 
typhimurium strains, but a dose-related increase of revertant colonies was observed at all 
concentrations in E. coli. Due to its low molar extinction coefficient in methanol, APR-246 is 
not classified as phototoxic. 

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It can be concluded that APR-246 induced clinical signs of adverse reactions when the 
compound was given at high dose levels as bolus injection or short-term infusion. The 
NOAEL of APR-246 in the 4-week repeat dose toxicity study in dogs given as a 2-hour 
infusion was 200 mg/kg/day. The mean systemic exposure at this dose level was 
63.7 g/mL (Cmax) and 129 g·h/mL (AUC). The mean plasma concentration at the NOAEL of 
200 mg/kg in the follow-up dog study was 114 g/mL (Cmax). With prolonged infusion time 
at the infusion rate of 100 mg/kg/h, APR-246 was well tolerated at much higher daily dose 
concentrations given over 7-days in cycles. No significant toxicity and no target organ 
toxicity were observed at 900 mg/kg/day in the cyclic study. The mean Cmax varied between 
61 to 196 µg/mL (males) and 65 to 190 µg/mL (females) during the study. The mean AUC on 
day 1 of the 3rd cycle was 1510 µg·h/mL (males) and was 797 µg·h/mL (females). 
 
2.6 
APR-246 Clinical Studies 
Table 2. Overview of Clinical Studies with APR-246. 
NCT number 
Study ID 
Indication 
Treatment/ 
Combination 
Status 
NCT00900614 
APR-246-01 
hematologic 
malignancies, prostate 
carcinoma 
APR-246  
Completed 
(Lehmann et al. 
2012)27 
NCT00900614 
APR-246-01 
Amendment 6 
hematologic 
malignancies  
APR-246 
Completed  
(Deneberg et al. 
2016)28 
NCT03072043 
MCC-18973 
 
NCT03588078 
GFM-APR246 
 
 
TP53 Mutant Myeloid 
Neoplasms (MDS/AML) 
APR-246 with azacitidine 
(Phase Ib also has APR-
246 monotherapy lead-in 
days -14 to -11) 
Phase Ib: 
enrolment 
completed 
 
Phase II: ongoing 
NCT02098343 
APR-407 
(PiSARRO) 
 
TP53-mutated high 
grade serous ovarian 
cancer, sensitive or 
partially sensitive to 
platinum 
Phase Ib: APR-246 with 
carboplatin/PLD 
Phase II: APR-246 with 
carboplatin/PLD vs. 
carboplatin/PLD alone 
Phase Ib: 
completed  
 
Phase II: ongoing 
NCT03268382 
APR-486 
(PiSARRO-R) 
 
TP53-mutated high 
grade serous ovarian 
cancer, platinum 
resistant 
APR-246 with PLD 
Ongoing 
NCT03391050 
APR-633 
BRAF V600 mutant 
melanoma resistant to 
APR-246 with dabrafenib 
Ongoing 

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NCT number 
Study ID 
Indication 
Treatment/ 
Combination 
Status 
(EMERA) 
 
dabrafenib/ trametinib 
NCT02999893 
16/012  
(APROC) 
 
esophageal or gastro-
esophageal junction 
cancers 
APR-246 with cisplatin 
and 5-FU 
Ongoing 
 
2.6.1 Phase Ib/II MDS (Moffitt) Trial 
This is an Investigator-led Phase Ib/II trial (MCC-18973), in which APR-246 (50, 75, and 100 
mg/kg lean body mass (LBM), via 6-hour daily IV infusion × 4 consecutive days) is given in 
combination with azacitidine (75 mg/m2 SC or IV for 7 days, first dose following the final 
APR-246 infusion on Day 4) every 28 days to patients with TP53 mutant myeloid neoplasms 
(MDS/AML). The first cycle also included a lead in phase with APR-246 in monotherapy days 
-14 to -11. 
 
The Phase Ib portion (safety/dose limiting toxicities (DLT) endpoint) has completed 
enrollment (N=12). No DLTs or serious adverse events (SAE) attributable to the study 
treatment have been reported to date. Myelosuppression has been the most common 
drug-related treatment-emergent adverse event (TEAE) reported to date.  
 
The Phase II part of the study completed enrollment in 2019.  Patients received 4.5 g 
(equivalent to 100 mg/kg LBM) APR-246 with azacitidine.  
 
In the Phase Ib portion, 100% of response evaluable patients had CR, mCR, PR or had 
hematological improvement at the 3-month assessment. Response rate and duration 
remains under investigation in the Phase 1b and II portions of the study. In addition, 
exploratory endpoints including p53 immunohistochemistry and TP53 variant allele 
frequency analysis, are planned. 
 
 
2.6.2 Ongoing Phase I/II in TP53 Mutated Advanced Ovarian Cancer 
APR-407 (PiSARRO) is a 2-part study in women with advanced high grade serous ovarian 
cancer (HGSOC) given APR-246 in combination with carboplatin and pegylated liposomal 
doxorubicin (PLD). This is based on the fact that >90% of HGSOC are TP53 mutant and in 
vitro and in vivo data suggesting synergism with platinum agents28. The APR-407 Phase Ib 
portion was completed in the European Union (EU) and the recommended Phase II dose of 
67.5 mg/kg (corresponding to 100 mg/kg LBM) was confirmed as safe to be administered in 
combination with carboplatin/PLD based upon assessment of cumulative safety data from 

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the Phase Ib. The APR-407 Phase II portion has completed accrual in the EU and US and is 
currently in blinded follow up. Final analysis is expected mid2019. 
 
2.6.3 Completed Study APR-246-01: First in Human APR-246 in Solid and Hematological 
Malignancies 
This first in human study was a multicenter, open label, non-comparative, Phase I/II dose 
escalating study of APR-246 infusions in patients with refractory hematological 
malignancies or prostate cancer (APR-246-01)27. The study assessed the safety, tolerability, 
pharmacokinetics and pharmacodynamics of multiple escalating doses of APR-246. An 
extension of this clinical trial has been conducted with the main objective to evaluate safety 
at an optimal dose in a more homogenous patient population (see below). The patients 
received APR-246 on 4 consecutive days as a 2-hour daily IV infusion. Dosing was 
conducted with three patients at each dose level. The first dose level was 2 mg/kg and was 
followed by 3, 10, 30, 60 and 90 mg/kg. The treatment phase was followed by a 17 days 
follow-up phase to reveal any late adverse effects. The highest feasible dose (HFD) was 
defined as the dose expected to result in maximal plasma concentration (Cmax) close to but 
not exceeding 110 
L in any single patient without showing signs of DLT, or the dose 
level below the dose where DLT occurred, whichever came first. In total 22 patients, 4 (18.2 
%) female and 18 (81.8 %) male with an average age of 67.0 years were enrolled into the 
study. The indications for the 22 included patients were AML (7 patients), prostate 
carcinoma (7 patients), non-Hodgkin´s lymphoma (NHL) (4 patients), chronic lymphocytic 
leukemia (CLL) (3 patients) and multiple myeloma (MM) (1 patient). Eighteen (18) patients 
completed the study, i.e., completed the day 21 visit and 4 patients were prematurely 
discontinued.   
 
In regards to activity, the apoptosis pattern in patients with hematological malignancies 
showed cell cycle changes compatible with cell cycle arrest in all patients with non T-cell 
malignancy33. Also, other apoptosis markers were affected such as increased staining for 
Annexin-V, up regulation of BAX (Bcl-2 associated X protein), NOXA and PUMA expression 
and up regulation of DcR2 (decoy receptor 2, a marker considered to be associated with 
senescence). The one responding patient in the initial Phase I clinical trial was the only TP53 
mutant AML patient. Specifically, this patient had a reduction of blast cell count from 46% 
to 26% and showed activation of p53 targets supporting in vivo activity.  
 
2.6.4 Completed Phase I/Ib Study APR-246-01 (Amendment 6) 
This was a multi-center, open label, non-comparative, Phase I, dose de-escalating study of 
APR-246 infusions in patients with refractory hematologic malignancies. In this study 
(Amendment No. 6) a longer infusion time was applied resulting in an increased exposure 
of APR-24628. In Amendment No. 6, the objective was to increase the knowledge of the 
optimal way to administer APR-246 and study the safety and tolerability as well as the 
pharmacokinetic (PK) profile of APR-246. Ten patients with AML or CLL were planned for 

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enrolment. The treatment schedule was 4 consecutive days with APR-246 with the modified 
dosing regimen of a start boosting infusion of 50 mg/kg during 45 min, followed by an 
85 mg/kg infusion for 5.15 hours. If toxicity was shown, the dose was to be decreased to 
Dose level 2 (45 mg/kg for 45 min [infusion rate 60 mg/kg/h], followed by 60 mg/kg 
[infusion rate 10 mg/kg/h] for 5.15 hours), on the discretion of the investigator and/or the 
Study Board. Out of the 2 AML patients with TP53 mutation, both had a blast reduction, one 
constituting a response according to the response criterion28. On the lower dose of 
67.5mg/kg, there were no DLTs or SAEs. Overall in this study there were 6/10 patients 
treated at 67.5 mg/kg or higher with no or only mild side effects supporting the 67.5mg/kg 
dose as the HFD and recommended for further development. 
 
PK was studied at selected time points during the treatment and the data showed that no 
accumulation of APR-246 was observed after four daily doses or after 3 cycles. Plasma 
clearance and volume of distribution were comparable between Day 1 and Day 4, 
suggesting time-independent kinetics. The PK parameters obtained in this study, were also 
in line with the previous single dose study (2-90 mg/kg, 2 h infusion) and linear kinetics 
could be concluded for APR-246 up to 135 mg/kg. Several patients tolerated the mid-dose, 
105 mg/kg treatment, where the Cmax was in the range of 45-85 µg/mL with an exposure up 
to 860 µg*h/mL (AUC0-24h), whereas one patient withdrew having the highest exposure 
(1060 µg*h/mL) in the whole study. In the patients, plasma concentrations consistently 
above those associated with effects in both ex vivo and in vivo pre-clinical models have been 
achieved. Four patients showed signs of response and 2 of them were responders 
according to the definition in the protocol. A response was observed in 4 of the 5 patients 
carrying mutant TP53. The effect of APR-246 on tumor burden and apoptosis markers 
indicates beneficial effects.   
 
2.6.5 APR-246 CNS Safety Overview 
CNS adverse events have been observed following APR-246 treatment in the clinical 
studies. These symptoms typically have an onset during or in direct connection with the 
drug infusion and include nausea/vomiting, dizziness/vertigo, psychiatric disorders and 
motor disturbances. They are fully reversible and usually mild and non-serious. However, 
cases with severe intensity have occurred, including events defined as a dose-limiting 
toxicity.  
 
To describe the observed clinical scope of these effects, potentially CNS events that have 
been reported in the following clinical studies are tabulated below: 
 
APR-246-01 (N=22) 
 
APR-246-01-Amd6 (N=10) 
 
APR-407 phase 1b (N=35) 
 
 

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Table 3 is an overview of all reported AEs without differentiation on severity or temporal 
relation to drug administration. Two columns are shown for study APR-407, one with drug-
related events only and one with all AEs reported in at least 10% of patients. The table 
shows the number of patients who reported at least one event (not number of events); a 
patient could report several events. The number of SAEs and DLTs in each category is given 
in parentheses. To capture potential CNS effects, all AEs in the following Medical Dictionary 
for Drug Regulatory Activities (MedDRA) System Organ classes are listed: 
 
Nervous system 
 
Ear and labyrinth 
 
Psychiatric 
 
General (not all shown, see below) 
 
Table 3. CNS Related Adverse Events in Clinical Studies (Number of Patients)  
 
APR-246-01 
All AEs  
APR-246-01 
Amd 6  
All AEs  
APR-407 Phase 
Ib 
Related AEs 
only  
APR-407 Phase 
Ib 
All AEs 
 
Administration 
2 h infusion 
6 h infusion 
6 h infusion 
6 h infusion 
Co-treatment 
 
 
+carboplatin/PLD
+carboplatin/PLD
Dosing regimen 
one 4-day 
course 
one 4-day 
course 
six 4-day courses 
in 28-day cycles 
six 4-day courses 
in 28-day cycles 
 
N=22 
N=10 
N=35 
N=35 
Ear and labyrinth 
Vertigo 
2 
2 
1 
 
Nervous system 
Dizziness 
4 
[1 SAE] [1 DLT] 
5 
22 
[1 SAE] 
24 
[1 SAE] 
Balance disorder 
1 
 
 
 
Ageusia 
1 
 
 
 
Dysgeusia 
1 
 
9 
12 
Headache 
3 [1 DLT] 
2 
9 
16 
Lethargy 
 
1 
 
 
Ataxia 
 
1 
 
 
Dyskinesia 
 
1 
[1 SAE] 
2 
 
Somnolence 
[1 DLT] 
2 
2 
 
Muscle 
contractions  
1 
[1 SAE] 
 
 
 
Sensory 
disturbance 
1 
[1 DLT] 
 
 
 

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APR-246-01 
All AEs  
APR-246-01 
Amd 6  
All AEs  
APR-407 Phase 
Ib 
Related AEs 
only  
APR-407 Phase 
Ib 
All AEs 
 
Dysarthria 
[1 DLT] 
 
 
 
Disturbance in 
attention 
 
 
1 
 
Hyperesthesia 
 
 
1 
 
Neuropathy 
peripheral 
 
 
1 
4 
Restless legs 
syndrome 
1
Tremor 
 
3 
5 
5 
Cerebral 
hemorrhage 
1 
[1 SAE] 
 
 
 
Psychiatric 
Confusional 
state 
2 
[1 SAE] [1 DLT] 
1 
1 
 
Dysphemia 
[1 DLT] 
 
 
 
Hallucination  
[1 DLT] 
 
 
 
Bradyphrenia 
 
 
1 
 
Disorientation 
 
1 
 
 
General 
Fatigue 
5 
4 
22 
29 
Gait disturbance 
 
 
1 
 
 
Nausea and vomiting may also be triggered from the CNS, but are not listed in this 
overview. From the category General disorders and administration site conditions, only 
fatigue and gait disturbance are listed, being potentially CNS-related. Other AEs reported in 
this category were pyrexia, edema, mucosal inflammation, malaise, death and disease 
progression. 
 
2.6.6 APR-246 Cardiac Safety Overview 
ECG data using Holter recordings have been collected in studies APR-407 and APR-486 
during the first cycle of treatment and were analyzed combined by a central ECG 
laboratory29. Recordings were performed during 24 hours on the first and fourth day of 
APR-246 infusion. On day 4 combination chemotherapy (carboplatin and PLD) in study 
APR-407 and PLD in study APR-486 was also administered simultaneously as the APR-246. 
Doses of APR-246 ranged from 35 mg/kg to 67.5 mg/kg in study APR-407 and was fixed at 
4.5 g in study APR-486. The ECG analysis set consisted of a total of 47 patients, 35 from 
study APR-407 and 12 from study APR-486.   

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For each infusion ECG measurements were performed at 5.75, 6.25, 7, 8, 9 and 24 h after 
start of the 6-hour APR-246 infusion. Evaluations were performed for heart rate and the RR, 
PR, QRS, QT, QTcB and QTcF intervals. Samples for APR-246 plasma concentrations were 
taken at the same time points for concentration-response analyses.  
 
Data were analyzed using two methods. For each predefined time point the change from 
baseline was calculated for each parameter expressed as mean change with a 90% CI by 
dose group (central tendency analysis). A concentration-response evaluation for changes in 
QTcF was furthermore performed.  
 
No marked effects on PR interval and QRS duration were noted. For heart rate no 
consistent changes were observed and no relationship to the APR-246 concentrations.   
 
The central tendency analysis indicated that administration of APR-246 caused a dose-
dependent increase in QTcF. At the highest dose tested in study APR-407 (67.5 mg/kg) and 
in study APR-486 (fixed dose of 4.5 g which corresponds to a dose of 64.3 mg/kg for an 
average person of 70 kg), the maximum mean increase from baseline was 22.4 and 20.1 
ms, respectively.  
 
The concentration-response analysis demonstrated a nonlinear relationship between 
APR-246 concentration and change in QTcF from baseline, as shown in Figure 3. An Emax 
model was found to best describe the data. 
 

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Figure 3. Concentration-response analysis for change in QTcF from baseline vs. APR-246 
concentration.  
Data for different dose cohorts combined. Mean change in QTcF with 90% CI shown at geometric 
mean Cmax at the maximum dose by study.  
 
At the geometric mean Cmax (68,915 ng/mL in study APR-407, 60,542 ng/mL in study 
APR-486) the estimated mean increase in QTcF is 14.1 ms (90% CI: 11.7, 16.4) at a dose of 
67.5 mg/kg in study APR-407, and 13.5 ms (90% CI: 11.2, 15.8) at a dose of 4.5 g in study 
APR-486. 
 
No patient had a value for QTcF > 500 ms or an increase from baseline exceeding 50 msec. 
 
The upper limit of the 90% CI for QTcF increase in the concentration-response analysis did 
not exceed 20 ms at Cmax for the maximum doses in either study. Increases below this limit 
are generally considered acceptable for oncology compounds.   
 
In the clinical studies with APR-246 there have been no reports of torsade de pointes 
arrhythmias, other clinically significant ventricular arrhythmias or sudden death. It is 
concluded that surveillance may be warranted when administering APR-246 to patients 
who start new concomitant medications that are known to cause QTc prolongation, and 
that magnesium and potassium levels should be monitored. In the current protocol, 

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patients with a QTc
 470 msec at baseline are excluded, unless due to bundle branch 
block and/or pacemaker and with approval of the medical monitor.  All patients who 
receive APR-246 are subject to monitoring of pre- and post-dose ECG on days 1 through 4 
of the first treatment cycle, and pre-dose ECG on day 1 of each subsequent cycle (see 
Section 6.2.1). The change in pre- and post-dose QTcF will be specifically analyzed to 
increase knowledge in this matter.  
 
2.7 
Dose Rationale for APR-246 in Combination with Azacitidine  
The effect of APR-246 has been investigated in combination with several cytotoxic and 
chemotherapeutic agents, including azacitidine. The confirmed MTD monotherapy APR-246 
dose, 67.5 mg/kg, equivalent to 100 mg/kg LBM or 4.5 g fixed dose, is currently being used 
in combination with azacitidine (75 mg/m2) in two clinical trials. Based on the responses 
seen to date, combined with the low toxicity profile in patients, 4.5 g APR-246 is considered 
a safe and appropriate dose.   
 
2.7.1 Rationale for Fixed APR-246 Dosing 
APR-246 was given as mg/kg body weight in APR-246-01 study as well as in the Phase Ib 
part of the APR-407 study (PiSARRO). After the population PK evaluation based on partial 
data showed that LBM was a slightly stronger influence than weight on the PK of APR-246 
the 67.5 mg/kg dose of APR-246 was converted and recalculated to 100 mg/kg LBM (37 
mg/kg as loading dose for 45 minutes followed by 63 mg/kg as maintenance dose for 5 
hours and 15 minutes) for the Phase II part of APR-407 (PiSARRO).  
 
Subsequently, a more thorough evaluation of the effect of body size-based vs fixed dosing 
was conducted using the updated population PK model and it was found that the effect of 
weight or LBM on the PK of APR-246 are weak28. It is therefore justified to apply fixed 
dosing of APR-246 as it will remove the risk for miscalculations of the dose and thereby 
contribute to the safe use of the product. 
 
Simulations were performed and the fixed dose regimen of 4500 mg was selected (details 
to be found in the I
Brochure).  Using a fixed dose of 4500 mg (split as 1500 mg 
for the first 45 min and 3000 mg for the subsequent 5 h and 15 min) gives estimated an 
average AUC of 571 mg·h/L in women, with 90% of female patients in the range of 311-910 
mg·h/L and an average AUC of 358 mg·h/L in men, with 90% of male patients in the range 
of 219-543 mg·h/L. The average simulated Cmax value in women treated at this fixed dose is 
57.5 mg/L (90% of female patients within 29.6-92.4 mg/L) and the average simulated Cmax 
value in men treated at this fixed dose is 34.9 mg/L (90% of male patients within 18.6-58 
mg/L). 
 

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2.8 
Potential Risks and Benefits 
2.8.1 Potential Risks 
Potential risks identified with APR-246 include transient CNS-related adverse events, bone 
marrow suppression, QTc prolongation, glucuronidation of acetaminophen.   
 
CNS adverse events: 
Non-clinical data have shown APR-246 induced CNS adverse effects at high concentration 
levels in mice and dogs. The effects were transient and occurred during or in direct 
connection with dosing (related to high Cmax). They are fully reversible, usually mild and 
non-severe, and may be managed by supportive medication (see Section 6.2.2) and/or dose 
reductions. However, cases with severe intensity have occurred, including events defined 
as a dose-limiting toxicity. Please consult with the Medical Monitor if you are unfamiliar 
with these events.  
 
Bone marrow suppression: 
No hematological toxicity was detected in nonclinical and clinical studies nor when APR/246 
has been dosed alone, but when combined with carboplatin and pegylated liposomal 
doxorubicin in the study in HGSOC performed under IND 124841, there have been events 
of agranulocytosis (×1), anemia (×3), febrile neutropenia (×6), leucopenia (×1) and 
thrombocytopenia (×8). To date there have been no clinical or non-clinical data to support 
or rule out a contribution from APR-246 to chemotherapy induced bone marrow 
suppression. 
 
QT Prolongation: 
Analysis of clinical ECG has indicated that administration of APR-246 causes a 
dose-dependent increase in QTcF. The upper limit of the 90% CI for QTcF increase in the 
concentration-response analysis did not exceed 20 ms at Cmax for the maximum doses. 
Increases below this limit are generally considered acceptable for oncology compounds. 
Due to the effect of APR-246 on the QTc interval, specific exclusion criteria related to 
cardiac safety in the clinical studies is implemented. 
 
Glucuronidation of Acetaminophen: 
Based on co-administration studies in mice, it cannot be excluded that APR-246 may have a 
negative influence on the glucuronidation of acetaminophen, and therefore potentially 
potentiating hepatotoxicity after an over-dose of acetaminophen. No hepatotoxicity caused 
by acetaminophen has been identified in the ongoing clinical studies.  
 
The Investigator's Brochure (IB) may be updated during the course of this study with 
additional risks and benefits. Please see the current IB for further details about the 
potential risks and benefits associated with this study. 
 

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2.8.2 Potential Benefits 
Based on the nonclinical safety profile, the emerging clinical safety profile in over 
300 patients, the early evidence of activity in TP53 mutated MDS patients, as well as the 
limited life expectancy and lack of effective treatments for these patients, the benefit/risk 
assessment supports the use of APR-246 for this trial. 
 
2.9 
Characteristics of a Well-Conducted Trial 
The following characteristics of an adequate and well-conducted trial will be implemented: 
 
1. 
The Investigators will be well qualified by scientific training and experience. 
 
2. 
Detailed Case Report Forms (CRFs) will be completed for every patient. 
 
3. 
Requirements for institutional ethics review as set forth by the appropriate 
Institutional Review Board/Independent Ethics Committee (IRB/IEC), Title 21 Code of 
Federal Regulations (CFR) Part 56, the European Union Directive 2001/20/EC and its 
associated Detailed Guidances, European Union GCP Directive 2005/28/EC, the ICH 
Guideline for Good Clinical Practice, Sections 3 and 4, and the terms of the 
Declaration of Helsinki (2013), will be followed. 
 
4. 
Requirements for informed consent in accordance with institutional guidelines, FDA 
requirements as specified in Title 21 CFR, Part 50, the European Union Directive 
2001/20/EC and its associated Detailed Guidances, European Union GCP Directive 
2005/28/EC, the ICH Guideline for Good Clinical Practice, Section 4.8, and the terms 
of the Declaration of Helsinki (2013), will be followed. 
 
5. 
Safety data will be recorded and evaluated. 
 
6. 
(Theradex Oncology) to ensure data accuracy. 
 
7. 
Drug accountability will be strictly maintained. 
 
8. 
This trial will be conducted according to Good Clinical Practice (GCP), the protocol 
and applicable regulatory requirements. 
 
2.10 Patient Population 
This study will enroll patients with documented diagnosis of MDS, according to WHO 
classification, and documented TP53 mutation that meets IPSS-R classification of 
intermediate, high, or very high-risk disease, who also meet the eligibility requirements of 
this protocol. 
 

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3.0  TRIAL OBJECTIVES AND PURPOSE 
3.1 
Primary Objectives 
1. To compare the complete response rate, defined as the proportion of patients who 
achieve CR, and duration of CR with APR-246 + azacitidine treatment vs. azacitidine 
only. 
 
3.2 
Secondary Objectives 
To measure the following with APR-246 + azacitidine treatment vs. azacitidine alone: 
1. Overall response rate (ORR) 
2. DOR 
3. Rate and time AML transformation 
4. Overall survival (OS)  
5. Relapse-free survival (RFS) 
6. Transition rate to hematopoietic stem cell transplant (HSCT) 
7. Safety profile 
8. Rate of red blood cell (RBC) and/or platelet transfusion independence (TI) for 56 
days (8 weeks) 
9. Pharmacokinetics of APR-246 and azacitidine  
 
3.3 
Exploratory Objectives 
1. Determine if biomarkers predictive for response to therapy can be derived from 
baseline molecular analyses of bone marrow or blood samples 
2. Determine the depth of remission by IHC, PCR, and other techniques in serial bone 
marrow or blood samples 
3. Investigate potential resistance mechanisms by molecular analysis of bone marrow 
or blood samples at disease progression  
 
 

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4.0 TRIAL DESIGN 
4.1 
Overview of Trial Design 
This will be a Phase III, multicenter, randomized study to compare the rate of CR and 
duration of CR, in patients with TP53-mutated MDS who will receive APR-246 and 
azacitidine or azacitidine alone. 
 
Treatment will be administered on an outpatient basis. No investigational or commercial 
agents or therapies other than those described below may be administered with the intent 
to treat the patient's disease.  
 
Patients will be randomized (1:1) to one of two arms, stratified by age (< 65 years versus 
 65): 
1. Experimental arm: APR-246 + azacitidine; or 
2. Control arm: Azacitidine 
 
The ITT population will be the primary analysis population for efficacy. All patients who are 
randomized on study will be considered eligible for the ITT population and will be used for 
demographics, baseline characteristics summaries. 
 
Patients may continue treatment to the end of the trial as long as toxicity remains 
acceptable, progression has not occurred and the patient has not withdrawn consent.  
Response and progressive disease will be assessed based on the Guidelines for 
Implementation of International Working Group (IWG) response criteria (see Appendix II) 
after every two treatment cycles the first year, then every three cycles. 
 
Investigators may choose to transition patients towards a stem cell transplantation (SCT) as 
appropriate after a response (CR, PR, mCR with HI, mCR without HI, HI) by the experimental 
or control treatment has been achieved. Patients who undergo SCT will be removed from 
study treatment and will be followed per the study calendar. 
 
 
4.2 
End of Study 
The end of the study is defined as the date of the last visit of the last patient participating in 
the trial.  Long-
. 
 
4.3 
Minimizing Bias 
All eligible patients entering the clinical trial will be randomized to either the experimental 
or the control treatment arms at a 1:1 ratio and using the following stratification factors to 
ensure a balance of patients: by age (< 65 years and  65 years). 
 
 

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4.4 
Drug Products 
4.4.1 APR-246 
Chemical Name: 2-hydroxymethyl-2-methoxymethyl-1-azabicyclo [2,2,2] octan-3-one)  
 
Storage, preparation and stability: The IMP (investigational medicinal product) should be 
stored at 2-8 C (35.6-46.4 F).  The IMP is formulated as a concentrate for solution for IV 
infusion, to be diluted with sterile 0.9% NaCl solution prior to administration.   
 
The solution for infusion should be prepared with the prescribed dosage for each patient in 
accordance with the protocol and separate technical instruction. After preparation of the 
ready to use solution for infusion the pH of the solution will range from slightly above 4 up 
to approximately 4.8, depending on dosage. The infusion will be slightly hypertonic, with an 
osmolarity of maximum 413 mOsm/L. The infusion to the patient should be finalized within 
24 h from the time of preparation. 
 
4.4.2 Azacitidine 
Chemical Name:  4-amino-1- -D-ribofuranosyl-s-triazin-2(1H)-one 
 
Formulation, preparation, storage and stability: Please see commercial package insert 
approved by regulatory agencies 30,31 
 
Route of Administration: Subcutaneous injection preferred*; or intravenous infusion.  
Azacitidine is administered SC or IV for 7 consecutive days (Days 4-10).  
* SC preferred but will allow for IV at the I
should be maintained over the 7-day treatment period (whichever route is used on Day 4, 
the other days should follow the same route of administration). 
 
4.5 
Duration of Therapy 
The projected Phase III duration is 30 36 months. Patients may continue treatment to the 
end of the trial while deriving clinical benefit, unless unacceptable toxicity, progression, 
death or patient withdrawal requires discontinuation. Patients may remain on protocol 
therapy after relapse or progression if they are continuing to derive clinical benefit in the 
opinion of the Investigator. 
 
4.6 
Trial Discontinuation  
For reasonable cause, the Sponsor may terminate this study prematurely. Written 
notification of the termination is required. Conditions that may warrant termination 
include, but are not limited to: 
 

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 The discovery of an unexpected, significant, or unacceptable risk to the patients 
enrolled in the study. 
 
Failure of the Investigators to enter patients at an acceptable rate. 
 
Insufficient adherence to protocol requirements (non-compliance). 
 
Lack of evaluable and/or complete data. 
 
Decision to modify the developmental plan of the drug. 
 
A decision on the part of the Sponsor to suspend or discontinue development of the 
drug. 
 
4.7 
Post-Treatment/Long-Term Follow-up  
After discontinuation from study treatment, every effort will be made to conduct a post-
treatment follow-up visit within 28 days after the last dose of the study drug.  All patients 
should be followed until death. Patients who discontinue any study treatment will be 
contacted by the study staff for survival status, and/or response assessments, transition to 
AML, until death as described in Section 7.6. 
 
4.8 
Investigational Drug Procurement/Drug Accountability/Disposition of Clinical Trial 
Supplies 
APR-246 should be requested by the Principal Investigator (or his/her authorized 
designees) at each participating institution. Instructions for ordering APR-246 will be 
provided in the Pharmacy Binder APR-246 may not be used outside the scope of this 
protocol, nor can it be transferred or licensed to any party not participating in the clinical 
study. Investigators may delegate the responsibility for drug ordering, storage, 
accountability, and preparation to their designees. Drug accountability records will be 
maintained for all clinical trial supplies. All drug received, dispensed, and returned by the 
patients must be recorded on a Drug Accountability Record (DAR).   
 
All empty and partially used vials and clinical trial supplies will be destroyed in accordance 
detailed documentation of the number and identification of vials which are destroyed, and 
copies of these documents will be provided to the Sponsor. Disposition of all unused boxes 
of study drug will be carried out according to instructions provided by the Sponsor at the 
end of the study after drug accountability is performed by the Theradex Oncology monitor.  
 
4.9 
Registration and Randomization 
Prior to registration and any study-specific evaluations being performed, all patients must 
have given written informed consent for the study and must have completed the pre-study 
evaluations (see Section 7.2).  Patients must meet all of the eligibility requirements listed in 
Section 7.5. There will be no eligibility waivers granted for this study. Patients will be 
registered and randomized on the study by using the Theradex Oncology Interactive Web 

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Response System (IWRS) automated patient registration system (see the Study Operations 
Binder for specific instructions). 
 
Sites will be asked to provide patient specific inclusion and exclusion criteria 
documentation for medical review (prior to randomization), including redacted NGS and 
bone marrow exam reports. 
 
 
 
 

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5.0   SELECTION AND WITHDRAWAL OF SUBJECTS 
Patients considered for enrollment on this study must have a diagnosis of MDS based on 
the WHO classification, documented TP53 mutation, and meets IPSS-R classification of 
intermediate, high, or very high-risk disease.  The patients must meet all inclusion and no 
exclusion criteria.  Investigators must be listed on the FDA 1572 form in order to be 
authorized to obtain information consent.  No study-specific procedures can be performed 
until the patient has signed an ICF that has been approved by the IRB or IEC.  Procedures 
that are performed prior to patients signing ICFs can be used to satisfy protocol 
requirements if these procedures are p
underlying disease or other illnesses.   
 
The study will enroll patients with TP53 mutations that are not benign or likely benign, as 
determined by local Next Generation Sequencing (NGS) and a study-specific variant 
interpretation algorithm. The TP53 variant interpretation will be verified centrally prior to 
inclusion.  Central NGS testing including TP53 will subsequently be conducted on all 
patients after enrollment. If there is discordance between local and central testing patients 
will be allowed to remain on study. 
 
5.1 
Inclusion Criteria 
Patients must fulfill all of the following criteria; there will be no eligibility waivers granted: 
 
1. Patient has signed the Informed Consent (ICF) and is able to comply with protocol 
requirements. 
2. Documented diagnosis of MDS, according to World Health Organization (WHO) 
classification (< 20% blasts), that meets IPSS-R classification of intermediate, high, or 
very high-risk disease.  
3. Patient has adequate organ function as defined by the following laboratory values: 
a) Creatinine clearance > 30 mL/min (by Cockcroft-Gault method; see Appendix IV)  
b) Total serum bilirubin < 1.5 × ULN, unless due to 
e, underlying 
disease of MDS, hemolysis or considered an effect of regular blood transfusions 
c) Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) < 2.5 × 
ULN, unless due to underlying disease of MDS  
4. 
the informed consent form 
5. Having at least one TP53 mutation which is not benign or likely benign 
6. An Eastern Cooperative Oncology Group (ECOG) performance status score of 0, 1, or 
2 (Appendix I).  
7. Females of childbearing potential, negative pre-treatment urine or serum pregnancy 
test. 
8. Females of childbearing potential and males with female partners of childbearing 
potential must be willing to use an effective form of contraception such as latex 
condom, hormonal birth control, intrauterine device or double barrier method 

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during chemotherapy treatment and for at least six months thereafter. 
 
5.2 
Exclusion Criteria 
Patients are to be excluded from the study if they meet any of the following criteria: 
1. Patient has a known history of HIV or active hepatitis B or active hepatitis C infection 
(testing not mandatory) 
2. Patient has any of the following cardiac abnormalities (as determined by treating MD): 
a. Myocardial infarction within six months prior to registration, 
b. New York Heart Association Class III or IV heart failure (Appendix III) or known 
left ventricular ejection fraction (LVEF) < 40%, as assessed by echocardiogram or 
MUGA scan; 
c. A history of familial long QT syndrome; 
d. Symptomatic atrial or ventricular arrhythmias not controlled by medications 
e. 
470 
correction (QTcF = QT/RR0.33). Note: Patients with QTcF 
470 msec and with 
bundle branch block and/or pacemaker rhythm may be enrolled after approval 
by Medical Monitor; 
3. Concomitant malignancies or previous malignancies with less than a 1-year disease free 
interval at the time of signing consent. Patients with adequately resected basal or 
squamous cell carcinoma of the skin, or adequately resected carcinoma in situ (e.g. 
cervix) may enroll irrespective of the time of diagnosis 
Prior exposure to azacitidine, decitabine or investigational hypomethylating agent, or 
induction chemotherapy for MDS or AML. Note: intensive chemotherapy for any other 
prior cancer is not exclusionary. 
4. Use of cytotoxic chemotherapeutic agents, or experimental agents (agents that are not 
commercially available) for the treatment of MDS within 14 days of the first day of study 
drug treatment  
5. Concurrent use of erythroid stimulating agents, G-CSF, or GM-CSF within 14 days of the 
first day of study drug treatment.  
6. History of allogeneic stem cell transplantation  
7. Pregnancy: Pregnant women are excluded from this study because APR-246 has not 
been studied in pregnant patients. Because there is an unknown but potential risk for 
adverse events in nursing infants secondary to treatment of the mother with APR-246, 
breastfeeding should be discontinued if the mother is treated with APR-246. 
8. Active uncontrolled infection. 
 
5.3 
Inclusion of Women, Minorities and Children 
This study is open to both male and female patients of all ethnicities. This study excludes 
patients aged < 18 years. 
 

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5.4 
Withdrawal Criteria 
Protocol therapy will be discontinued at any time if any of the following situations occur: 
 
1. Clinically significant progressive disease  
2. 
nt, precludes further 
therapy. 
3. Patient refusal 
4. A pattern of noncompliance with study medication or protocol-required evaluations 
and follow-up visits 
5. Intercurrent illness: a condition, injury, or disease unrelated to cancer in the opinion of 
the investigator, that renders continuing treatment unsafe or regular follow-up 
impossible 
6. At the discretion of the Investigator that it is in the best interest of the patient to 
withdraw 
7. Pregnancy 
8. Study termination by the sponsor 
 
5.4.1 Withdrawn Subjects  
When a patient is removed from the study, the Investigator will clearly document the 
reason in the medical record and complete the appropriate CRF page describing the reason 
for discontinuation.  In addition, every effort should be made to complete the appropriate 
assessments listed in Section 7.5.   
 
5.5 
Noncompliance 
All instances of noncompliance and all resulting protocol deviations will be entered in the 
CRF and/or documented in monitoring reports.  
 
 
 

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6.0 TREATMENT OF SUBJECTS 
6.1 
Drug Preparation and Administration 
At the pharmacies, the IMP vials are to be stored at 2-8ºC (35.6-46.4 F). At the pharmacies 
and at the study centers, the prepared APR-246 study product (diluted in sodium chloride 
solution) is to be stored at not more than 25ºC. The infusion should be completed within 24 
hours from the time of preparation (see Pharmacy Binder).  
 
APR-246 treatment (Experimental Arm only) will be administered on Days 1-4, and 
azacitidine on Days 4-10 (Figure 4). Treatment may be administered on an outpatient basis. 
No investigational or commercial agents or therapies other than those described below 
may be administered with the intent to treat the patient's disease.  
 
Patients will be randomized (1:1) to 1 of 2 arms, Experimental or Control arm. 
 
6.1.1 Experimental Arm (APR-246 + Azacitidine) 
APR-246 will be administered as a 6-hour intravenous infusion daily on days 1 4 of each 
28-day cycle. APR-246 fixed dose is 4.5 g.  APR-246 is administered in a 2-step infusion: 
Step 1: Loading dose of 1.5 g for the first 45 minutes (± 2 min) 
Step 2: Maintenance dose of 3 g over 5 hours 15 minutes (± 30 min) 
Detailed instructions on vial concentration, preparation and dispensing can be found in the 
Pharmacy Binder. The infusion timing, including start/stop times and the time of rate 
change, must be recorded. 
 
Azacitidine will be given at the standard dose of 75 mg/m2 SC or IV over 7 consecutive days, 
Days 4-10. On Day 4 azacitidine is administered immediately after the APR-246 infusion. SC 
method is preferred but IV is allowed at the Investigator s discretion. However, the same 
route should be maintained over the 7-day treatment period (whichever route is used on 
Day 4, the other days should follow the same route of administration). Detailed instructions 
on preparation and administration can be found in the Pharmacy Binder, current package 
insert, and in Section 6.1.2, below. 
 
 
Figure 4. Drug Administration Schema for Experimental Arm: APR-246 and Azacitidine 
 

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6.1.2 Control Arm (Azacitidine Only) 
Azacitidine will be given at the standard dose of 75 mg/m2 SC or IV over 7 consecutive days, 
Days 4-10, every 28 days. SC method is preferred but IV is allowed at the Investigator s 
discretion. However, the same route should be maintained over the 7-day treatment period 
(whichever route is used on Day 4, the other days should follow the same route of 
administration). 
 
Detailed instructions on preparation and administration can be found in the Pharmacy 
Binder, and current package insert. 
 
Control Arm: Azacitidine only 
 
 
Figure 5. Drug Administration Schema for Control Arm: Azacitidine Only 
 
6.2 
Criteria for Treatment, Retreatment and Dose Modifications 
6.2.1 APR-246 
This section outlines the requirements for proceeding with treatment with APR-246, and 
the protocol rules for APR-246 dose modification due to toxicity.  
 
The 

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Table 4 describes the routine ECG requirements from screening through Cycle 4 for 
patients in Experimental Arm: 

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Table 4. ECG Requirements in Experimental Arm 
Time Point 
ECG, n 
Timing 
Baseline/Screening 
Triplicate 
 Within 28 days of Cycle 1 Day 1 
Cycle 1, Days 1-4 
Triplicate 
Pre-dose; Post dose (6 hrs. after start of infusion; ± 30 min) 
Cycles 2+, Day 1 
Triplicate 
Pre-dose 
 
At screening (baseline), 12-lead ECGs should be collected in triplicate to confirm QT interval 
does not exceed 470 msec. QT interval must be calculated from a mean of all three ECG 
0.33). 
 
During Cycle 1 ECG should be collected in triplicate prior to infusion of APR-246 and at the 
end of infusion of APR-246 (6 hours after start of infusion, ± 30 min) on Days 1 - 4. QTcF 
must be calculated from a mean of all three ECG readings to confirm it does not exceed 
470 msec.  
 
If a pre-
0.33). Serum concentrations of 
electrolytes should be monitored and corrected, if necessary. Additionally, concomitant 
medication should be reviewed and adjusted, if necessary. ECG may be repeated at any 
time, including the same day. APR-246 may only be administered when QTcF has returned 
to < 470 msec. If APR-246 is given on the same day, procedures outlined in the Schedule of 
Study Evaluations (Table 8) must be followed. If APR-246 cannot be administered on the 
same day, that dose must be omitted from the cycle. 
 
If there is a significant change in QTcF, defined as either: a) increase > 60 msec from 
baseline (or pre-
1 msec, i.e. consistent with 
NCI CTCAE Grade 3 QTc prolongation, QTc prolongation must be confirmed by a manual 
0.33). If confirmed, 
the therapy should be interrupted until a cause (electrolyte disorders or an effect of a 
concomitant medication) has been identified and addressed, and QTcF has returned to < 
470 msec. If all other causes for clinically significant QT interval prolongation are excluded, 
APR-246 must be permanently discontinued. 
 
During subsequent cycles ECG should be collected in triplicate prior to infusion of APR-246 
on Day 1 of each cycle. QTcF must be calculated from a mean of all three ECG readings to 
confirm it does not exceed 449 msec. If pre-dose QTcF is 450-469 msec, APR-246 may be 
administered, and additional triplicate ECG should be performed at the end of infusion (6 
hours after start of infusion, ± 30 min). If post-dose ECG shows a significant change in QTcF, 
defined as either: a) increase > 60 msec from baseline (or pre-dose), or b) increase to an 
1 msec, i.e. consistent with NCI CTCAE Grade 3 QTc prolongation, QTc 
correction (QTcF = QT/RR0.33). If confirmed, the therapy should be interrupted until a cause 

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(electrolyte disorders or an effect of a concomitant medication) has been identified and 
addressed, and QTcF has returned to < 470 msec. If all other causes for clinically significant 
QT interval prolongation are excluded, APR-246 must be permanently discontinued. If QTcF 
is unchanged or there is no significant change, additional ECG is not required during that 
cycle. 
 
If repeated QTcF measurements show a stable QTcF < 450 msec, or if QTcF remains stable 
within the interval of 450  469 msec with no significant change at the end of infusion 
during several cycles of treatment, reducing the number of ECGs performed in the study 
may be discussed with the Medical Monitor. 
 
If a patient starts treatment with another medication known to prolong QT interval at any 
time during the study therapy, an additional pre- and post-dose (6 hours after start of 
infusion, ± 30 min) ECG should be performed on the next treatment day. For patients who 
do not tolerate the protocol-specified dosing schedule, one dose level reduction is 
permitted (Table 5) in order to allow the patient to continue the study treatment. A second 
dose reduction could be permitted following discussion with the Sponsor and Medical 
Monitor. 
 
Table 5. APR-246 Dose Levels 
Dose 
Modification 
APR-246 Dose 
Starting Dose 
Level (DL) 
APR-246 4.5 g/day 
1.5 g (for first 45 minutes) + 3.0 g (for 5 hours 15 minutes) 
One dose level 
reduction (DL-1) 
APR-246 4.0 g/day  
1.33 g (for first 45 minutes) + 2.67 g (for 5 hours 15 minutes) 
Second dose level 
reduction (DL-2)* 
APR-246 3.5 g/day 
1.16 g (for first 45 minutes) + 2.34 g (for 5 hours 15 minutes) 
* Discuss with Sponsor and Medical Monitor before implementing second dose level reduction. 
The rationale behind this dose reduction scheme is the steep relation between Cmax and dose, e.g. 
the suggested 11% and 22% reductions in dose result in 19% and 33% lowering of the average Cmax, 
respectively 
 
All dose modifications, interruptions or discontinuations must be based on the worst 
preceding toxicity as graded by the NCI Clinical Toxicity Criteria (NCI-CTCAE version 5). Once 
a dose has been reduced during a treatment cycle, re-escalation during subsequent cycles 
may be permitted following discussion with the Medical Monitor. If the administration of 

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APR-246 is interrupted for reasons other than toxicity, then treatment with APR-246 may be 
resumed at the same dose. The same provision applies if the patient experienced an 
unacceptable toxicity not specifically described in Table 6, provided that this toxicity 
ied.  
 
Following 4 cycles of therapy for responding patients (i.e. CR, PR, HI, mCR with HI, mCR 
without HI) treatment with APR-246 and azacitidine can be delayed for up to 14 days to 
allow for count recovery at Investigator discretion pending discussion with the Sponsor and 
Medical Monitor.  
 
Non-hematologic Grade 4 treatment related adverse events will lead to permanent 
discontinuation, irrespective of recovery time, unless otherwise specified. Exceptions would 
include nausea/vomiting/diarrhea which can be controlled by medications and/or 
asymptomatic electrolyte imbalances which can be corrected. In addition, in most 
instances, patients that experience a prolonged treatment interruption because of an 
adverse event and/or a Grade 3 adverse event will decrease the dose of study drug after 
their recovery (see specific tables for dose adjustment guidelines). 
 
If any drug-related Grade 3 or 4 toxicity that is not clearly related to azacitidine is observed, 
APR-246 dose must be reduced for the next and subsequent cycles. 
 
Patients requiring >2 dose reductions for APR-246 will be permanently discontinued from 
study drug. Patients who permanently discontinue APR-246 or azacitidine should have 
follow-up within 28 days after discontinuation of all study treatment or resolution of the AE 
 Grade 1, whichever occurs first, that includes all study assessments appropriate to 
monitor the event. 
 

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Table 6. Recommendations for APR-246 Dose Modifications and Criteria for Treatment 
Interruption and Re-Initiation with Treatment-Related Adverse Events  
Any changes in dose must be recorded on the Dosage Administration Record CRF. 
 
Renal Toxicities 
 
Parameter 
Worst toxicity   
Dose Modifications for APR-246 
Serum 
Creatinine 
Grade 1 (< 1.5 × baseline) 
Maintain dose level  
Grade 2  
(> 1.5 to 3.0 × baseline)  
 
If first occurrence, then maintain dose level 
If second or more consecutive occurrence, then 
 1 dose 
level 
Grade 3  
(> 3.0  6.0 × baseline)  
 1 dose level 
If not resolved or resolved in > 7 days, evaluate if other 
contributing factors are present. If none, or after 
consideration of best interest of the patient, discontinue 
patient from APR-246.  
If other factors present, consider continuing after 
 1 dose 
level 
Grade 4 (> 6.0 × baseline)  
Permanently discontinue patient from APR-246 
Common Terminology Criteria for Adverse Events (CTCAE) version 5.  
 
Hepatic Toxicities  
 
Parameter 
Worst toxicity  
Dose Modifications for APR-246 
Bilirubin  
Grade 1 (> ULN - 1.5 × ULN) 
Maintain dose level with LFTs  monitored as per 
protocol 
Grade 2 (> 1.5 - 3.0 × ULN) with ALT or 
 
 
If 
maintain dose level 
If second or more consecutive occurrence or if 
resolved in > 7 days, then 
 1 dose level 
Grade 3 (> 3.0 - 10.0 × ULN) with ALT or 
 
then: 
 1 dose level. If no 
subsequent event, consider re-escalation to original 
dose level. 
 1 dose 
level. 
If second or more consecutive occurrence or if not 
resolved or resolved in > 7 days, evaluate if other 
contributing factors are present. If none, or after 
consideration of best interest of the patient, 
discontinue patient from APR-246.  
If other factors present, consider continuing after 
 1 
dose level. 
Grade 4 (> 10.0 × ULN) 
Permanently discontinue patient from APR-246 

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Parameter 
Worst toxicity  
Dose Modifications for APR-246 
AST or ALT 
Grade 1 (> ULN - 3.0 × ULN if baseline 
was normal; 1.5 - 3.0 × baseline if 
baseline was abnormal) 
Maintain dose level with LFTs  monitored per protocol 
Grade 2 (> 3.0 - 5.0 × ULN if baseline 
was normal; >3.0 - 5.0 × baseline if 
baseline was abnormal) in the absence 
of total bilirubin elevation to > 2.0 × 
ULN 
 
if first consecutive occurrence, 
then maintain dose level 
If second or more consecutive occurrence or if  
resolved in > 7 days, then 
 1 dose level 
Grade 3 (> 5.0 - 20.0 × ULN if baseline 
was normal; > 5.0  20.0 x baseline if 
baseline was abnormal) in the absence 
of total bilirubin elevation to > 2.0 × 
ULN 
Omit dose until 
 
if first consecutive occurrence, 
then maintain dose level. 
If second or more consecutive occurrence or if not 
resolved or resolved in > 7 days, evaluate if other 
contributing factors are present. If none, or after 
consideration of best interest of the patient, 
discontinue patient from APR-246. If other factors 
present consider continuing after 
 1 dose level 
Grade 4 (> 20.0 × ULN if baseline was 
normal; > 20.0 × baseline if baseline 
was abnormal) 
Permanently discontinue patient from APR-246 
-induced liver injury, 
DILI, and is defined as AS
other than the suspected drug, can be found to explain the combination of increases, eg, elevated ALP indicating 
cholestasis, viral hepatitis, or another drug. 
Common Terminology Criteria for Adverse Events (CTCAE) version 5.  
 
LFTs include albumin, ALT, AST, total bilirubin (fractionated if total bilirubin > 2.0 × ULN), alkaline phosphatase. 
 
 
Hematological Toxicities  
 
Parameter 
Worst toxicity  
Dose Modifications for APR-246 
Febrile neutropenia 
ANC < 0.5 × 109/L, temperature of 
than 1hour 
Omit dose until 
, then 
 1 
dose level 
Thrombocytopenia 
Grade 4 (PLT < 25 × 109/L)  and 
major bleeding event 
Permanently discontinue patient from APR-246 
Only applicable for patients with normal baseline absolute neutrophil count (ANC) and platelets. For patients with 
low (abnormal) baseline ANC and/or platelets that do not return to baseline (pre-cycle) after a clinically significant 
decrease following treatment, please contact the Medical Monitor. 
Common Terminology Criteria for Adverse Events (CTCAE) version 5. 
 
 
 
 

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Other Non-Hematological Toxicities 
 
Parameter 
Worst toxicity  
Dose Modifications for APR-246 
CNS  dizziness,  
dyskinesia and ataxia 
Grade 1 
Maintain dose level 
Grade 2 
If resolved (to  Grade 1) with medical therapy, continue same 
dose level 
If not resolved despite treatment interruption and maximal 
medical therapy, stop infusion and 
 1 dose level for 
subsequent dose 
Grade 3 
Stop infusion and give medical therapy. If resolved (to  Grade 
1) with medical therapy, infusion may continue at the 
 
 
 1 dose level for subsequent dose  
Grade 4 
Permanently discontinue patient from APR-246. 
Infusion Related 
 Reaction 
Grade 1 
Maintain dose level. 
Grade 2 
Maintain dose level; Symptomatic management (e.g., 
antihistamines, corticosteroids, narcotics, IV fluids) 
Grade 3 
If resolved (to 
rade 1) in < 4 hours with treatment 
interruption and medical therapy (e.g., antihistamines, 
corticosteroids, narcotics, IV fluids), continue same dose level 
and rate. 
If not resolved in < 4 hours despite treatment interruption and 
maximal medical therapy, stop infusion and 
 1 dose level for 
subsequent dose 
Grade 4 
Permanently discontinue patient from APR-246. 
Nausea/Vomiting/ 
Diarrhea 
Grade 1  
Maintain dose level  
Grade 2  
If resolved (to 
rade 1), then maintain dose level 
If not resolved despite maximal medical therapy, 
then 
 1 dose level 
Grade 3  
If resolved (to 
rade 1), then maintain dose level 
If not resolved despite maximal medical therapy, then 
 1 
dose level 
Grade 4  
Permanently discontinue patient from APR-246 
Any Other Toxicity 
Grade 3 or 4 
 1 dose level 
Common Terminology Criteria for Adverse Events (CTCAE) version 5. 
 
Treating physicians should use clinical judgment and may consult the Medical Monitor for 
guidance with dose modifications.  
 
 
6.2.2 Management of CNS Adverse Events  
If a patient reports any clinical adverse event of any grade during the administration period 
of APR-246 that could be considered to originate from the CNS (e.g. dizziness, vertigo, 
nausea) then the patient will be given a rescue medication as per the institutional standard 
of care. 
 

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Dose modifications have been successfully used to manage potential CNS effects occurring 
during the infusion. For any clinical adverse event Grade 
3, the infusion should 
 Grade 1 within 2 hours, 
the infusion may be resumed at the same infusion rate. If the same symptoms do occur or 
increase in severity during re-challenge the infusion should be stopped. 
 
If the event lasts longer than 2 hours, then the APR-246 infusion should be discontinued for 
that day, the remaining drug should be discarded, and toxicity should be managed 
according to recommendations in Table 6.  
 
After an adverse event considered as related, a single level dose reduction of APR-246 is 
allowed. 
Dose 
reduction 
is 
recommended 
after 
any 
Grade 
3 
CNS 
AEs.   
 
In prior studies, prochlorperazine 10 mg orally tid (three times daily) has been reported to 
be an effective treatment that may also be used prophylactically. When prochlorperazine is 
used prophylactically, start the day prior to the Day 1 and continue 10 mg tid to day 4 (as 
needed). The US label for prochlorperazine does not list QT prolongation as a known risk 
associated with use of this drug.  
 
Re-escalation after dose reduction due to any APR-246-related toxicity may be permitted 
following discussion with the Medical Monitor. 
 
6.2.3 Management of Nausea and Vomiting  
Patients who experience nausea and vomiting in association with APR-246 infusion will be 
prescribed appropriate rescue treatment and prophylaxis (e.g., anti-nausea or anti-emetics 
medication) as per institutional guidelines. Patients who receive additional drugs that are 
known to cause QT prolongation (Section 6.3) must be monitored for any signs of QT 
prolongation via an ECG before and after the APR-246 infusion. 
 
If QTc > 501 msec is observed in a patient concomitantly treated with another QT 
interval prolonging drug, this drug should be stopped and treatment with APR-246 
may be restarted when QTc < 470 msec (refer to section 6.2.1). 
 
A list of suggested rescue medications is provided below in Table 7. 
 

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Table 7. Medications for Managements of Nausea and Vomiting 
 
Drug 
Dosage 
QT Prolongation1 
Ondansetron 
8 mg PO administered 30 minutes before 
the start of infusion or per label 
Yes 
Dolasetron 
100 mg PO administered within one 
hour before start of infusion or per label 
Yes 
Palonosetron 
0.5 mg PO administered approximately one 
hour prior to the start of infusion or per 
label 
No 
Prochlorperazine 
10 mg PO three times daily.  Continue until 
the end of Day 4 of the cycle. When used 
prophylactically in subsequent cycles, start 
the day prior to Day 1 administration of 
APR-246 
No 
1 Please refer to Section 6.2.1 for details on concurrent administration of medications known to 
cause QTc interval prolongation. 
 
 
6.2.4 Management of Infusion Reactions 
If a patient experiences an infusion reaction during the study, the infusion will be stopped 
and appropriate medical care (e.g., epinephrine, oxygen, H1 and H2 antagonists, and/or 
corticosteroids) will be administered.32 
 
6.2.5 Azacitidine Dose Adjustments 
Azacitidine dose modifications will follow the Prescribing Information30,31 or institutional 
practice, supported by international recommendations. Azacitidine should be administered 
SC or IV over 7 consecutive days, Days 4-10, every 28 days. A single missed dose (for any 
adding an 
additional dosing day for azacitidine (e.g. Day 11) so that the patient receives the total 7 
days of treatment per cycle. If the azacitidine dose interruption is > 2 days, discuss with the 
Medical Monitor. 
 
6.3 
Concomitant Treatment  
If patients experience prolonged myelosuppression they will be placed on infection 
prophylaxis per standard of care. 
 
Patients may not receive any other drug to treat MDS while on study. Patients may 
continue their baseline medication(s) as long as they are not prohibited. Palliative and 
supportive care (e.g., anti-emetics, bisphosphonates) for disease related symptoms will be 
offered to all patients in the study per institutional practices. Adverse events will be treated 

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as clinically indicated. All concomitant medications that are currently in use or that become 
necessary during the study should be recorded. 
 
Hydroxyurea may be administered before study start and up to the time of study 
randomization. At 
tosis 
during the early treatment cycles, hydroxyurea may be administered. The hydroxyurea 
should be discontinued as soon as clinically appropriate.   
 
If the patient develops an acute infusion reaction (  Grade 2), the infusion must be stopped 
Grade 1. Premedication (e.g., dexamethasone) may be 
used after the first cycle. 
 
The prophylactic use of G-CSF is prohibited. Supportive use of G-CSF for treatment of 
cytopenias may be allowed at the discretion of the investigator per institutional practices. 
 
 
6.4 
Monitoring Subject Compliance 
All instances of protocol deviations will be entered into Monitor Express and will be 
reviewed by the Investigator, Sponsor and appropriate Theradex designee.  
 
 
 
 
 
 
 
 
 
 
 

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7.0   STUDY EVALUATIONS 
7.1 
Schedule of Study Evaluations 
Table 8. Schedule of Study Evaluations (also described in Sections 7.2 through 7.5) 
Study Calendar 
Evaluation a 
 
Screening 
 
Cycle 1  
Cycle 2 and Subsequent Cycles 
End of 
Odd 
Cycles 
End of 
Even 
Cycles 
Q3M 
After 
Month 12 
End of 
Treat-
ment o
Long-
Term 
Follow-
Upp
D1 
D2 
D3 
D4 
D5-
10 
D
8 
D15
b 
D22
b 
D1
c 
D2 
D3 
D4 
D5
-10 
D8 
D15
b 
D22b 
Informed consent 
× 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
TP53 confirmation d 
×  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Medical history e 
× 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical examination f 
× 
× 
 
 
 
 
 
 
 
× 
 
 
 
 
 
 
 
 
 
×
Height 
× 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Weight 
× 
× 
 
 
 
 
 
 
 
× 
 
 
 
 
 
 
 
 
 
 
×
Vital signs f 
× 
× 
× 
× 
× 
× 
× 
 
 
× 
× 
× 
× 
× 
× 
 
 
 
 
 
×
ECOG PS 
× 
× 
 
 
 
 
 
 
 
× 
 
 
 
 
 
 
 
 
 
 
×
APR-246 (experimental arm)g 
 
× 
× 
× 
× 
 
 
 
 
× 
× 
× 
× 
 
 
 
 
 
 
 
 
Azacitidine h 
 
 
 
 
× 
× 
× 
 
 
 
 
 
× 
× 
× 
 
 
 
 
 
 
Bone marrow collectioni 
× 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
× 
× 
×
×
Response assessmentr 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
× 
× 
 
Hematology j 
× 
× 
 
 
 
 
× 
× 
× 
×j 
 
 
 
 
× 
× 
× 
 
 
× 
×
×
Blood chemistry k 
× 
× 
 
 
 
 
× 
× 
× 
× 
 
 
 
 
× 
× 
× 
 
 
 
×
Creatinine clearancek 
× 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Pregnancy test l 
× 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
ECG m  
× ×m 
×m 
×m 
×m 
 
 
 
 
× 
 
 
 
 
 
 
 
 
 
 
APR-246 PK sample n 
 
× 
× 
 
× 
 
 
 
 
× 
× 
 
× 
 
 
 
 
 
 
 
 
Azacitidine PK sample n 
 
 
 
 
× 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Survival & transformation to AML 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
×
×
Transfusion log 
 
From 8 weeks prior to randomization to end of treatment/off treatment 
Adverse events 
 
Starting at the time of eligibility confirmation through 30 days after last doseq 
Concomitant medications 
× 
Reviewed throughout study 

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Footnotes to Schedule of Study Evaluations 
 
a. All screening/baseline evaluations will be performed within 28 days prior to the start of APR-246 and azacitidine treatment. In the event that a 
visit or test cannot be scheduled on the exact visit day, a window of ±3 days is allowable. 
b. A window of ±3 days applies to this study visit. 
c. After the first cycle, Day 1 evaluations of subsequent cycles are to be done within 3 days prior to next cycle drug administration. 
d. Confirmation of TP53 status for eligibility will be performed centrally using the local lab report. 
e. Full medical history will be obtained at baseline for safety and eligibility purposes; this will include any issues/clinically significant findings 
from 28 days prior to screening date. 
f. 
Physical exam and vital signs (including blood pressure, heart rate, respiration rate and temperature) will be completed for safety purposes 
and clinically significant items will be recorded as AEs where appropriate. In Experimental Arm, vital signs will be collected prior to APR-246, 
2 hours into infusion and at end of infusion (EOI) (±30 min. at all time points).  Both arms:  if azacitidine is given via IV infusion, vital signs 
will be taken before the infusion (within 0-2 hours) and at EOI (30-60 minutes); if azacitidine is given via SQ injection, vital signs will 
be taken before the injection (within 0-2hours).  In the Control Arm, the physical exam and vital signs are not needed on each day 
prior to the first day of azacitidine administration; vital signs will be assessed on treatment days only. 
g. For Experimental Arm Only, APR-246 is administered IV on days 1-4 of each 28-day cycle. 
h. Azacitidine is administered SC over 7 consecutive days, on Days 4-10 of each 28-day cycle. On Day 4 azacitidine is administered immediately 
after the APR-246 infusion. SC route is preferred but site may give IV at 
. The same route should be maintained 
over the 7-day treatment period (whichever route is used on day 4, the other days should follow the same route of administration).
i. 
Bone marrow aspirate sample and biopsy core is collected at baseline and when bone marrow is sampled for disease assessment. If no 
aspirate is available, then peripheral blood is acceptable. Bone marrow assessment completed within 28 days of signing consent will be 
accepted to fulfill screening requirement, as long as it has been completed following the last MDS treatment (excluding ESAs (erythropoietic 
stimulating agent)). 
j. 
Hematology including hemoglobin, hematocrit, MCV, platelet count, blasts, WBC and WBC differentials weekly. The peripheral blood sample 
collected on Day 1 of each cycle starting at Cycle 2 will be for disease assessment, if bone marrow aspirate is not available (see footnote r). 
For patients with documented CR at disease assessment following Cycle 2, hematology and blood chemistry assessments will be required for 
D1 of each subsequent cycle and more frequently per the discretion of the treating physician. Otherwise performed weekly until CR.

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k. Blood chemistry including sodium, potassium, BUN, glucose, ALT/AST, alkaline phosphatase, total protein, total bilirubin, albumin, creatinine, 
calcium, chloride and magnesium weekly. At screening, the creatinine clearance may be calculated from the serum creatinine. A 24-hour 
For patients with documented CR at disease assessment 
following Cycle 2, hematology and blood chemistry assessments will be required for D1 of each subsequent cycle and more frequently per 
the discretion of the treating physician. Otherwise perform weekly until CR. 
l. 
Pregnancy test; for women of childbearing potential, a negative pregnancy test (urine or serum) must be documented between Screening and 
first day of treatment on study. Must be documented prior to 1st dose of treatment on study. 
m. Standard 12-lead ECGs to be performed in triplicate at baseline/screening, on Days 1 - 4 of Cycle 1 (experimental arm only) and on Days 1 of 
each subsequent cycle (experimental arm only) with patient in a semi-recumbent position. Please consult Table 10 for ECG collection 
schedule.  
n. Please consult section 8.3, Table 9 for PK collection schedule. 
o. Patients discontinuing treatment early should complete their end of treatment visit within approximately 28 days of their last dose of 
investigational product. Physical exam, vital signs, adverse event reporting, CBC (complete blood count), and blood chemistry and BM 
aspirate and biopsy with NGS analysis should be performed if feasible.   
Off Treatment assessment includes best response, date of first response, date of loss of response, reason for discontinuation.  
Off study CRF: vital status, date of death/last contact, transformation to AML and the date of transformation to AML if applicable. 
p. Long-term follow up can be done remotely (e.g. via telephone, via Local Practitioner or via review of medical records).  Assuming there is no 
withdrawal of consent, patients who stop study treatment (APR-246 or azacitidine) for any reason (e.g. toxicity, transition to SCT, PD) will 
continue long-term follow-up (see Section 7.6).  
If a patient is removed from the study due to unacceptable adverse events, the event(s) will be followed until resolution or stabilization of the 
adverse event. 
q. AE description, grade and start date and resolution date should be captured and documented. 
r. 
Response assessment is performed at the end of each cycle (every 4 weeks), based on peripheral blood and bone marrow (at the end of even 
cycles), and peripheral blood alone (at the end of odd cycles).   

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7.2 
Pre-Study Assessments (All Patients) 
Prior to performing any procedures or assessments, the nature of the study and the 
potential risks associated with the trial will be explained to all patient candidates and 
written informed consent will be obtained. Patients who choose to participate will have to 
consent to the biobanking program and will be asked to sign the mandatory section in the 
main study consent form related to biobank samples. Evaluations obtained as part of 
routine medical care and performed during the screening period may be used in place of 
the study specific evaluations. Patients will acknowledge and agree to the possible use of 
this information for the study by giving informed consent.  
 
7.2.1 Screening (All patients) 
All pre-treatment evaluations are to be performed within 28 days of Day 1 unless otherwise 
noted. 
 
Informed Consent  
 
TP53 mutation confirmation  send local report to vendor (see lab manual for 
instructions) 
 
Medical history  must include a thorough assessment and documentation of all 
transfusions received beginning from 8 weeks prior to randomization to end of 
treatment/off treatment; record transfusions on transfusion log.   
 
Physical examination 
 
Height 
 
Weight  
 
ECOG performance status 
 
Creatinine clearance (Cockcroft-Gault method; see Appendix IV) 
 
Vital signs: including blood pressure, heart rate, respiration rate and temperature 
 
Hematology: hemoglobin, hematocrit, MCV, platelet count, blasts, WBC and WBC 
differentials. 
 
Blood chemistry including sodium, potassium, BUN, glucose, ALT/AST, alkaline 
phosphatase, total protein, total bilirubin, albumin, creatinine, calcium, chloride and 
magnesium.  
 
Serum pregnancy test: For patients with reproductive potential. 
 
ECG: Standard 12-lead ECGs to be performed with patient in a semi-recumbent 
position in triplicate. 
 
Concomitant medication 
 
Bone marrow aspirate and biopsy - Bone marrow assessment completed within 28 
days of signing consent will be accepted to fulfill screening requirement as long as it 
has been completed following the last MDS treatment (excluding ESAs). 
 
Baseline bone marrow aspirate and biopsy core for exploratory objectives. If no 
aspirate is available, then peripheral blood is acceptable. 
 
Adverse Events: baseline, at the time of eligibility confirmation. 

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7.2.2 Randomization 
Randomization will occur after screening, once a patient has had their eligibility confirmed, 
has agreed to participate and is ready to start on the study treatment.  
 
Stratified randomization will be based on age group (< 
then assigned to the particular treatment arm from the randomization list for that stratum. 
Randomization will be balanced within each stratum with patients randomly assigned with 
equal probability (1:1 allocation) to one of the two treatment arms (APR-246 + azacitidine or 
azacitidine). Permuted block randomization (random allocation within block) will be used to 
assign patients to treatments within each stratum. 
 
7.3 
Experimental Arm (APR-246 + Azacitidine) 
In the event that a visit or test cannot be scheduled on the exact visit day, a window of ±3 
days is allowable.   
 
7.3.1 Cycle 1 
7.3.1.1 Days 1-10  
Day 1 examinations marked * do not need to be repeated if already performed within 3 
days prior to day 1 cycle 1.   
 
 
Transfusion log: must capture all transfusions beginning from 8 weeks prior to 
randomization to end of treatment/off treatment. 
 
Adverse Events: All adverse events since the last visit should be recorded. Even 
though pre-medicated, patients should be closely monitored. 
 
Concomitant medications. 
 
Physical examination: Day 1* weight, body surface area.  
 
ECOG performance status: Day 1.  
 
Vital signs. Before infusion, 2 hours into each infusion (± 30 min) and at EOI (± 30 
min) 
 
Hematology: Day 1* hemoglobin, hematocrit, MCV, platelet count, blasts, WBC and 
WBC differentials. 
 
Blood chemistry: Day 1* sodium, potassium, BUN, glucose, ALT/AST, alkaline 
phosphatase, total protein, total bilirubin, albumin, creatinine, calcium, chloride and 
magnesium.  
 
ECG: Standard 12-lead ECG to be performed with patient in a semi-recumbent 
position; pre-dose (prior to the PK blood draw before the infusion) and at the end of 
infusion, per Table 10. 
 
Pharmacokinetics for APR-246: on Days 1, 2, 4, per Section 8.3 

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APR-246 administration. 
 
Azacitidine administration. Administered daily for 7 consecutive days starting on 
Day 4 (Days 4 to 10 inclusive).  The same route should be maintained over the 7-day 
treatment period (whichever route is used on Day 4, the other days should follow 
the same method route of administration). On Day 4 azacitidine is given 
immediately after APR-246 infusion. 
 
Pharmacokinetics for azacitidine: Day 4, per Section 8.3 (at selected sites only) 
 
7.3.1.2 Week 2 (Day 8 ± 3 Day)  
 
Adverse events 
 
Concomitant medications 
 
Hematology 
 
Blood chemistry  
 
7.3.1.3 Perform Weekly 
 
Adverse events 
 
Concomitant medications 
 
Hematology weekly 
 
Blood chemistry weekly 
 
7.3.2 Cycle 2 Day 1 ± 3 Day (same as Cycle 1 Day 29) 
Tests should be performed prior to first dose 
Day 1 examinations marked * do not need to be repeated if already performed within 3 
days prior to day 1 of cycle 2.   
 
Adverse Events: All adverse events since the last visit should be recorded. Even 
though pre-medicated, patients should be closely monitored. 
 
Concomitant medications. 
 
Physical examination: Day 1* weight, body surface area. 
 
ECOG performance status: Day 1.  
 
Vital signs.  
 
Hematology: Day 1* hemoglobin, hematocrit, MCV, platelet count, blasts, WBC and 
WBC differentials. 
 
Blood chemistry: Day 1* sodium, potassium, BUN, glucose, ALT/AST, alkaline 
phosphatase, total protein, total bilirubin, albumin, creatinine, calcium, chloride and 
magnesium.  
 
ECGs pre-dose. Standard 12-lead ECGs to be performed in triplicate on Day 1 with 
patient in a semi-recumbent position. Perform prior to the PK blood draw before 
infusion, per Table 10. 
 

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7.3.2.1 Days 1-10 
 
Adverse events: All adverse events since the last visit should be recorded. Even 
though pre-medicated, patients should be closely monitored. 
 
Concomitant medications. 
 
Vital signs. Before infusion, then 2 hours into each infusion (±30 min) and at EOI 
(± 30 min) 
 
APR-246 administration (Days 1  4). 
 
Azacitidine administration. Administered daily for 7 consecutive days starting on 
Day 4 (Days 4 to 10 inclusive). The same route should be maintained over the 7-day 
treatment period (whichever route is used on Day 4, the other days should follow 
the same method route of administration). On Day 4 azacitidine is given 
immediately after APR-246 infusion. 
 
Pharmacokinetics for APR-246: Cycle 2 and 3: Days 1, 2, 4 
 
 
7.3.2.2 Week 2 (Day 8 ± 3 Day) 
 
Adverse events 
 
Concomitant medications 
 
Hematology 
 
Blood chemistry  
 
7.3.2.3 Week 3 (Day 15 ± 3 Day) 
 
Adverse events 
 
Concomitant medications 
 
Hematology 
 
Blood chemistry 
 
7.3.2.4 Week 4 (Day 22 ± 3 Day) (Rest Period) 
 
Adverse events 
 
Concomitant medications 
 
Hematology 
 
Blood chemistry   
 
7.3.2.5 End of Cycle 2 
 
Bone marrow/response assessment 
 
Bone marrow aspirate and biopsy core for exploratory objectives. If no aspirate is 
available, then peripheral blood is acceptable.  
 

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7.3.3 Cycle 3 Day 1 ±3 Day (same as Cycle 2 Day 29) and Onwards (Cycle 4+) 
These tests should be performed prior to first dose 
 
Adverse Events: All adverse events since the last visit should be recorded. Even 
though pre-medicated, patients should be closely monitored. 
 
Concomitant medications. 
 
Physical examination: Day 1* weight, body surface area.  
 
ECOG performance status: Day 1.  
 
Vital signs.  
 
Hematology: Day 1* hemoglobin, hematocrit, MCV, platelet count, blasts, WBC and 
WBC differentials. 
 
Blood chemistry: Day 1* sodium, potassium, BUN, glucose, ALT/AST, alkaline 
phosphatase, total protein, total bilirubin, albumin, creatinine, calcium, chloride and 
magnesium.  
 
ECGs: see Table 10. 
 
7.3.3.1 Days 1-10  
 
Adverse Events: All adverse events since the last visit should be recorded. Even 
though pre-medicated, patients should be closely monitored. 
 
Concomitant medications. 
 
Vital signs. Before infusion, then 2 hours into each infusion (± 30 min) and at EOI (± 
30 min) 
 
APR-246 administration (Days 1  4). 
 
Azacitidine administration. Administered daily for 7 consecutive days starting on 
Day 4 (Days 4 to 10 inclusive). The same route should be maintained over the 7-day 
treatment period (whichever route is used on Day 1, the other days should follow 
the same method route of administration). On Day 4 azacitidine is given 
immediately after APR-246 infusion 
 
ECG: Standard 12-lead ECGs to be performed with patient in semi-recumbent 
position: 
o Day 1 only: Perform prior to the PK blood draw before infusion, per Table 10. 
 
Cycle 3 Only: Pharmacokinetics APR-246 as per Section 8.3 
 
Hematology weekly 
 
Blood chemistries weekly  
 
 
7.3.3.2 Week 2 (Day 8 ± 3 Day) 
 
Adverse events 
 
Concomitant medications 
 
Hematology. For patients with documented CR at disease assessment following 
cycle 2, hematology and blood chemistry assessments will be required for D1 of 
each subsequent cycle and more frequently per the discretion of the treating 

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physician. 
 
Blood chemistry. For patients with documented CR at disease assessment following 
cycle 2, hematology and blood chemistry assessments will be required for D1 of 
each subsequent cycle and more frequently per the discretion of the treating 
physician. 
 
7.3.3.3 Week 3 (Day 15 ± 3 Day) 
 
Adverse events 
 
Concomitant medications 
 
Hematology weekly as needed (see above) 
 
Blood chemistry weekly as needed (see above) 
 
7.3.3.4 Week 4 (Day 22 ± 3 Day) (Rest Period) 
 
Adverse events 
 
Concomitant medications 
 
Hematology weekly as needed (see above) 
 
Blood chemistry weekly as needed (see above) 
 
7.3.4 End of Odd Numbered Cycles Up to Month 12 
 
Response assessment, based on peripheral blood 
 
7.3.5 End of Even Numbered Cycles Up to and Including Month 12 
 
Bone marrow sample for response assessment 
 
Bone marrow aspirate and biopsy core for exploratory objectives. If no aspirate is 
available, then peripheral blood is acceptable. 
 
7.3.6 After Month 12 
Every 3 Month Visits: 
 
Adverse events 
 
Concomitant medications 
 
Bone marrow aspirate and biopsy / response assessment 
 
Bone marrow aspirate and biopsy core for exploratory objectives. If no aspirate is 
available, then peripheral blood is acceptable. 
 
CBCs as needed. 
 
7.4 
Control Arm (azacitidine) 
In the event that a visit or test cannot be scheduled on the exact visit day, a window of ±3 
days is allowable.  After the first cycle, Day 1 of each subsequent cycle is the same as Day 
29 of the previous cycle. 

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7.4.1 Each Cycle Day 1 ±3 Days (same as Day 29 of previous cycle) through Day 10 
Tests should be performed prior to first dose 
Day 1 examinations marked * do not need to be repeated if already performed within 3 
days prior to day 1 cycle 1.  
 
 
Adverse Events: All adverse events since the last visit should be recorded. Even 
though pre-medicated, patients should be closely monitored. 
 
Concomitant medications. 
 
Physical examination: Day 1*. Weight, body surface area. 
 
ECOG performance status: Day 1.  
 
Vital signs. If azacitidine is given IV: before (within 0-2 hours) and EOI (30-60 
minutes). If azacitidine is given SC: before administration (within 0-2 hours). 
 
Hematology: Day 1* hemoglobin, hematocrit, MCV, platelet count, blasts, WBC and 
WBC differentials. 
 
Blood chemistry: Day 1* sodium, potassium, BUN, glucose, ALT/AST, alkaline 
phosphatase, total protein, total bilirubin, albumin, creatinine, calcium, chloride and 
magnesium.  
 
Azacitidine will be administered daily for 7 consecutive days starting on Day 4 (Days 
4 to 10 inclusive). SC preferred but will allow for IV at the discretion of the treating 
physician. If SC (or IV) is used on Day 4, the other days should follow the same 
method of administration. 
 
Pharmacokinetics for azacitidine: Only Cycle 1 Day 4, per Section 8.3. 
 
 
7.4.2 Perform Weekly 
 
Adverse events 
 
Concomitant medications 
 
Hematology 
 
Blood chemistry 
 
7.4.3 End of Odd Numbered Cycles Up to Month 12 
 
Response assessment, based on peripheral blood 
 
 
7.4.4 End of Even Numbered Cycles Up to and Including Month 12 
 
Bone marrow sample for response assessment 
 
Bone marrow aspirate and biopsy core for exploratory objectives. If no aspirate is 
available, then peripheral blood is acceptable. 
 

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7.4.5 After Month 12 
Every 3 Month Visits: 
 
Adverse events 
 
Concomitant medications 
 
Bone marrow aspirate and biopsy / Response assessment 
 
Bone marrow aspirate and biopsy core for exploratory objectives. If no aspirate is 
available, then peripheral blood is acceptable. 
 
CBCs as needed. 
 
7.5 
End of Treatment Visit (All Patients) 
This visit should take place within 28 days of the last dose of APR-246 or azacitidine, if 
treatment is stopped early for any reasons.   
 
 
Physical examination: weight, body surface area.  
 
Vital Signs 
 
Disease Assessment 
 
Bone marrow aspirate and biopsy core for exploratory objectives. If no aspirate is 
available, then peripheral blood is acceptable. 
 
ECOG performance status 
 
Hematology 
 
Blood chemistry 
 
Safety: Adverse events must be collected up to 30 days after the last dose. 
 
7.6 
Long-Term Follow-Up 
This can be done remotely (e.g. via telephone, via General Practitioner or via review of 
medical records).  
 
Assuming there is no withdrawal of consent, patients who stop study treatment (APR-246 
or azacitidine) for any reason (e.g. toxicity, transition to SCT, PD) will continue long-term 
follow-up: 
1. Patients who discontinue study treatment to receive SCT: 
a. Collect post SCT response assessments, transformation to AML and survival 
every month until relapse or death, whichever occurs first.  
b. After PD, collect data for survival and transformation to AML every 6 months 
until death. 
2. Responders (CR, PR, mCR with HI, mCR without HI, HI) who discontinue study treatment 
for other reasons than progressive disease or SCT: 
a. Collect response assessments, transformation to AML and survival monthly until 
relapse or death, whichever occurs first. 

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b. After relapse/progression, continue collecting data for survival and 
transformation to AML every 6 months until death. 
3. Non-Responders: patients who discontinue study treatment due to progressive disease:  
a. Collect data for survival and transformation to AML every 6 months until death. 
 
 

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8.0   STUDY ASSESSMENTS 
8.1 
Safety Assessments 
All randomized patients who received any amount of study medication will be evaluated for 
safety. Adverse events (AEs) are collected during the study, from the time of eligibility 
confirmation, until 30 days after the last dose of study treatment. AEs are graded according 
to NCI CTCAE version 5.0.  Patients will be assessed at baseline and throughout the study 
according to the Schedule of Study Evaluations including AEs, laboratory abnormalities, 
vital signs, physical exam, ECG and performance status. 
 
8.1.1 Safety Analysis 
Safety data including AEs, vital signs, laboratory data, ECG, and physical exam will be 
tabulated for the safety population. Adverse events will be tabulated by body system, 
preferred term, severity, and relationship to treatments. The tabulation of laboratory 
parameters will include the normal ranges for each parameter.  Each value will be classified 
as falling above, below, or within the normal range. Laboratory parameters will also be 
tabulated by maximum NCI-CTCAE severity grade. 
 
8.1.2 Reporting of Adverse Events 
8.1.2.1 Adverse Events 
An adverse event (AE) is any untoward medical occurrence in a patient or clinical 
investigation subject administered a pharmaceutical product that does not necessarily 
have a causal relationship with the treatment.  An adverse event includes abnormal 
laboratory values or test results, even when they do not induce clinical signs or symptoms 
or require therapy. 
 
The adverse event reporting period begins at the time of eligibility confirmation and will 
continue up to 30 days after the last dose of study treatment. 
 
At each evaluation patients should be interviewed in a non-directed manner to elicit 
potential adverse reactions from the patient.  The occurrence of an adverse event will be 
 and/or signs 
and symptoms. 
 
All adverse events (except Grade 1 and 2 laboratory abnormalities that do not require an 
intervention), regardless of causal relationship, are to be recorded in the case report form 
and source documentation.  Adverse events are to be coded according to MedDRA version 
21.1. The Investigator must determine the intensity of any adverse events according to the 
NCI Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0 (see 

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http://ctep.info.nih.gov) and their causal relationship. Those AEs not covered by these 
criteria will be graded as follows:  
 
1. 
Mild: Discomfort noticed, but no disruption of normal daily activity. Prescription 
drug not ordinarily needed for relief of symptom but may be given because of 
personality of patient. 
 
2. 
Moderate: Discomfort sufficient to reduce or affect normal daily activity. Patient is 
able to continue in study; treatment for symptom may be needed. 
 
3. 
Severe: Incapacitating, severe discomfort with inability to work or to perform normal 
daily activity. Severity may cause cessation of treatment with test drug; treatment 
for symptom may be given and/or patient hospitalized. 
 
4. 
Life-Threatening: Symptom(s) place the patient at immediate risk of death from the 
reaction as it occurred; it does not include a reaction that, had it occurred in a more 
serious from, might have caused death. 
 
5.  
Fatal: Event caused the death of the patient.  
 
Adverse events will be followed until resolution or stabilization while the patient remains 
on-study. Once the patient is removed from study, events thought to be related to the 
study medication will be followed until resolution or stabilization, unless, in the 
 
disease, or until the patient starts a new treatment. 
 
Laboratory values are to be graded based on the NCI-CTCAE version 5.0 criteria. 
 
8.1.2.2 Attribution Definitions 
An adverse event is considered to be associated with the use of the Investigational agent if 
the attribution is determined as possible, probable or definite. Attribution of AEs will be 
recorded in the CRF as: 
 
 
Unrelated: The AE is clearly not related to the study treatment. 
 
Unlikely: The AE is doubtfully related to the study treatment. 
 
Possible: The AE may be related to the study treatment. 
 
Probable: The AE is likely related to the study treatment. 
 
Definite: The AE is clearly related to the study treatment. 
 

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8.1.2.3 Definition of an Unexpected Adverse Event 
An unexpected adverse event is defined as any adverse drug experience, the specificity or 
severity of which is not consistent with the current IB; or, if an IB is not required or 
available, the specificity or severity of which is not consistent with the risk information 
described in this protocol or in the regulatory agency study authorization application.   
 
Unexpected, as used in this definition, refers to an adverse drug experience that has not 
been previously observed (e.g., included in the IB) rather than from the perspective of such 
experience not being anticipated from the pharmacological properties of the 
pharmaceutical product. 
 
8.1.2.4 Serious Adverse Event (SAE) 
A serious adverse event is defined as any untoward medical occurrence that at any dose: 
 
1. 
Results in death, 
 
2. 
Is life-threatening (i.e., the patient was at risk of death at the time of the event. It 
does not refer to an event which hypothetically might have caused death if it was 
more severe), 
 
3. 
Requires in-patient hospitalization or prolongation of existing hospitalization 
excluding that for pain management, disease staging/re-staging procedures, or 
catheter placement unless associated with other serious events,  
 
4. 
Results in persistent or significant disability/incapacity, or 
 
5. 
Is a congenital anomaly/birth defect. 
 
Important medical events that may not result in death, be life-threatening, or require 
hospitalization may be considered serious adverse drug events when, based on 
appropriate medical judgment, they may jeopardize the patient or subject and may require 
medical or surgical intervention to prevent one of the outcomes listed above. 
 
8.1.2.5 Pregnancy 
Any pregnancy diagnosed during the study, or that occurs within 30 days after stopping 
study medication, must be reported immediately to the Investigator. Pregnancy, in and of 
itself, is not regarded as an adverse event, unless there is suspicion that study medication 
may have interfered with the effectiveness of a contraceptive medication. If the patient 
becomes pregnant while on-study, the study drug should be immediately discontinued. 
Pregnancy information about a female patient or a female partner of a male patient should 
be reported immediately from the time the Investigator first becomes aware of a 

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pregnancy or its outcome. This will be performed by the Investigator completing a 
Pregnancy Form and forwarding it to Theradex Oncology fax number at (609) 799-1567 or 
sending via email to SafetyDeskUS@Theradex.com.  
 
Any pregnancy complication, spontaneous abortion, elective termination of a pregnancy 
for medical reasons, outcome of stillbirth, congenital anomaly/birth defect, or serious 
adverse event in the mother will be recorded as an SAE and will be reported as described in 
Section 8.1.2.6. 
 
8.1.2.6 Reporting of Serious Adverse Events 
Adverse events classified as serious require expeditious handling and reporting to 
Theradex Oncology to comply with regulatory requirements. 
 
All SAEs, regardless of relationship to the study drug, which occur during the period of 
observation (from the time of eligibility confirmation to 30 days following the date of the 
last dose of study drug administration) must be immediately reported (within 1 business 
day of the initial observation of the event) by email, fax or telephone to the Theradex 
Oncology Safety Desk. Notification by email is preferred. After this period, only those SAEs 
assessed as possibly, probably or definitely related to the study drug should be reported. 
 
SAEs will be reported to: 
Theradex Oncology Safety Desk 
 
 
 
 
Telephone: (609) 799-7580 
 
 
 
 
Fax: (609) 799-1567 
 
 
 
 
Email: SafetyDeskUS@Theradex.com 
 
8.1.2.7 Safety Monitoring Plan  
The medical monitor will be responsible for ongoing safety monitoring for the study per 
the detailed safety plan. This monitoring will include a review of all serious adverse events 
as they are reported by the study site. The medical monitor will also be in contact with site 
monitors and will be available to discuss any issues concerning safety with site staff. Safety 
data will be reviewed periodically by Theradex Medical Monitor and the Sponsor Medical 
Officer. 
 
8.1.3 Independent Data Monitoring Committee (IDMC) 
The Independent Data Monitoring Committee (IDMC) will be formed to, at pre-specified 
data-points, review and evaluate the study progress and safety, and to assess reports on 
cumulated serious adverse events (SAEs). Based on these reviews the IDMC will provide 
recommendations to the sponsor Aprea regarding the scientific and ethical integrity, the 
progress and possible modifications of the study. 
 

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8.2 
Efficacy Assessments 
The primary endpoint is CR per the modified IWG (Cheson et al, 2006; see Appendix II) and 
time between achieving CR and relapse of disease. 
 
8.2.1 Duration of Response 
Duration of response (DOR) is measured from the time of initial response to disease 
relapse/progression or death. 
 
8.2.2 Overall Survival 
Overall survival is defined for all randomized patients, as measured from the date of 
randomization until the date of death. 
 
8.2.3 Stem Cell Transplant  
Patients may go on to receive SCT and this is likely to be a reflection of a positive outcome 
to treatment with the randomized therapies. The primary approach will be to use a 
treatment policy strategy (ICH E9 (R1) addendum)33 where patients who receive SCT will 
continue to be followed for OS and relapse from any response with their date of 
death/relapse used in the analysis. If for any reason a patient receives SCT prior to a 
documented CR they will not be counted as a response. The inverse probability of 
censoring weights (IPCW)34 method will be used adjusting for baseline predictors of 
outcome and time-dependent covariates such as blast, platelet and neutrophil counts. For 
patients who receive SCT, this method effectively replaces their outcome with patients who 
most resemble them and who do not receive SCT, in terms of response treatment and 
baseline attributes.  The IPCW approach is preferred to censoring patients who receive SCT, 
as receipt of SCT is associated with a good response to therapy and would introduce 
informative censoring and underestimate the true DOR. 
 
 
 

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8.3 
Pharmacokinetics  
Experimental arm: Sparse PK sampling for APR-246 will be done at all sites in cycles 1-3, on 
Days 1, 2 and 4.  
For both arms, azacitidine PK will be done at selected sites in cycle 1, on Day 4.  
Due to the instability of both drugs a strict routine for serum preparation and handling 
must be followed, as outlined in the Laboratory manual. 
 
Table 9. Sparse PK Blood Sampling Time Points for APR-246 (first 3 cycles) and 
azacitidine (first cycle only) 
Experimental Arm: PK for APR-246 (Cycles 1  3) at all sites, all patients1 
APR-246 Sample Time Points 
D1 
D2 
D4 
Prior to APR-246 infusion 
× 
× 
× 
At the end of APR-246 infusion 
× 
 
× 
30  60 min after APR-246 infusion 
× 
 
×1 
1 Selected Sites Only: the sampling on Day 4 of the APR-246 infusion is coordinated with azacitidine 
sampling. Please see Laboratory Manual for sites participating in azacitidine PK sample collection: 
Section 1.2.3, Figure 4 (part C), and page 44 (PK Blood Sampling and Collection Form).  
 
Experimental and Control Arms: PK for azacitidine (Cycle 1) 
Azacitidine Sample Time Point 
C1D4 
Prior to azacitidine administration 
× 
At the end of azacitidine administration 
× 
0.25 hour after administration 
× 
0.5 hour after administration 
× 
1 hour after administration 
× 
2 hours after administration 
× 
4 hours after administration 
× 
 
 
 
 
 
 
 
 

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8.4 
ECG in Experimental Arm: ECG for APR-246 
Table 10 describes the routine ECG requirements from screening through cycle 4: 
 
Table 10. ECG Requirements in Experimental Arm 
Time Point 
ECG, number 
Timing 
Baseline/Screening 
Triplicate 
Must be within 28 days of C1D1 
Cycle 1, Days 1-4 
Triplicate 
Pre-dose; Post dose (6 hrs. after start of infusion; ± 30 
min) 
Cycles 2+, Day 1 
Triplicate 
Pre-dose 
 
If repeated QTcF measurements show a stable QTcF < 450 msec, or if QTcF remains stable 
within the interval of 450  469 msec with no significant change at the end of infusion 
during several cycles of treatment, reducing the number of ECGs performed in the study 
may be discussed with the Medical Monitor. 
 
If a patient starts treatment with another medication known to prolong QT interval at any 
time during the study therapy, an additional pre- and post-dose (6 hours after start of 
infusion, ± 30 min) ECG should be performed on the next treatment day. 
 
Please consult Section 6.2.1 for additional requirements for proceeding with treatment 
with APR-246. 
 
8.5 
TP53 Testing 
Patients are enrolled based on central interpretation of local NGS TP53 sequencing results 
confirming at least one TP53 mutation not defined as benign or likely benign (see 
Laboratory Manual).  Next-generation sequencing data report (de-identified, with only the 
 must be sent to the central laboratory for evaluation 
of TP53 data. 
 
 

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9.0  STATISTICS 
9.1 
Sample Size 
This trial will include 154 patients with 77 patients randomized in a 1:1 ratio to each of the 
two treatment arms (APR-246 + azacitidine treatment versus azacitidine treatment alone). 
 
If the true CR rate is 50% for the treatment arm and 25% for the control arm, the trial will 
have 90% power to detect a statistically significant effect in favor of the APR-246 at a 
2-sided alpha = 0.05 significance level. 
 
9.2 
Analysis Populations 
Intent-to-Treat (ITT) population: All patients who are randomized on study will be 
considered eligible for the ITT population and will be used for demographics, baseline 
characteristics summaries. The ITT population will be the primary analysis population for 
efficacy. 
 
Efficacy-Evaluable (EE) population: All patients who complete at least one treatment cycle of 
APR-246 and azacitidine and who have at least one post-treatment clinical response 
assessment. Patients who fail to complete one post-treatment clinical response 
assessment will also be considered EE if they show clear evidence of clinically significant 
disease progression. The EE population will be the secondary analysis population for 
efficacy. 
 
Safety population: Patients will be evaluable for safety if they receive at least one dose of 
APR-246 or azacitidine. The safety population will be used to summarize exposure and 
safety parameters. 
 
Pharmacokinetics: Patients will be evaluable for pharmacokinetics if at least one sample for 
PK evaluation has been obtained. 
 
9.3 
Statistical Methods 
9.3.1 Efficacy Analyses 
Primary endpoint CR will be summarized for all randomized patients (ITT) as the proportion 
of patients (%) with CR.  CR will be compared between treatment arms using a Cochran-
Mantel-Haenszel (CMH) test stratified by age (< 65 years versus  65 years). In addition to 
presenting the CR rate and associated exact 95% CI for each treatment arm, the treatment 
effect will be described using the CMH estimate of the common odds ratio together with its 
associated 95% CI. 
Duration of response (DOR) is defined as the time from the date when criteria for 

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response) are met to the date of relapse, progression, or death due to any cause, 
whichever occurs first. Patients alive without relapse or progression will have their DOR 
censored at the date of the last clinical assessment. The duration of CR will be summarized 
in each treatment arm by providing the median DOR together with associated 95% CI, 
using Kaplan-Meier methodology.  
Overall response will be summarized in number (%) of patients in each category of 
responses (CR, PR, mCR with HI, mCR without HI, HI). ORR will be analyzed by using the 
similar method as primary endpoint CR. DOR, as defined above, will also be evaluated in 
regards to ORR. 
Time to AML is calculated from first day of study treatment to first onset of AML. Kaplan-
Meier methodology will be utilized. Rate of AML transformation will be analyzed by using 
the same method as primary endpoint CR. 
Survival data are collected at treatment and follow-up periods.  Patients will be followed 
until death. Overall Survival (OS) is defined as the number of days from the date of 
randomization to the date of death. Kaplan-Meier methodology will be utilized. 
Relapse-free survival (RFS) is defined as the time from the date of randomization to disease 
relapse, progression or death from MDS, whichever occurs first. If neither event occurs, RFS 
will be censored at the date of the last assessment. Kaplan-Meier methodology will be 
utilized. 
Time to AML, OS and RFS will be analyzed using the similar methods as DOR. 
Transition rate to SCT will be analyzed using the similar methods as complete response 
rate. 
Important subgroup analyses will be detailed in the Statistical Analysis Plan.   
 
9.3.2 Exploratory Analyses 
Descriptive statistics/results from the assays (DNA mutation panel, RNA expression profile, 
p53 IHC, TP53 VAF by NGS, PCR) will be written. Not all analyses listed may be performed. 
 
9.3.3 Safety Analysis 
Safety data will be summarized for the safety population. These data will include adverse 
events and laboratory parameters. Adverse event terms will be coded using the MedDRA®, 
version 21.1 or higher. Adverse events will be summarized by body system, preferred term, 
severity, and relationship to treatment. Serious adverse events, deaths, and AEs leading to 
early discontinuation of study drug will be summarized. Laboratory parameters will be 
summarized by maximum NCI-CTCAE v5.0 severity grade and also by change from pre-
treatment to scheduled time points using descriptive statistics. Laboratory parameter 
listings will include the normal ranges for each parameter. Each value will be classified as 
falling above, below, or within the normal range.  

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Data summaries will include only treatment-emergent adverse events (TEAEs), defined as 
events occurring at the start of infusion on Day 1, Cycle 1 up to and including 30 days after 
last dose. 
 
9.3.4 Pharmacokinetic Analysis 
APR-246 concentrations will be determined by a validated high-performance liquid 
chromatography (HPLC) tandem mass spectrometry (LC/MS/MS) method. A population PK 
model will be used to estimate individual Cmax, AUC and CL for each patient. APR-246 AUC 
and Cmax will then be tested for association with signs of efficacy and safety. If an 
observable trend exists, a PK/PD model will be developed to evaluate the exposure-
response relationship between APR-246 plasma exposure and outcome measures. 
Demographic and clinical data (ethnicity, current age, body weight, sex, disease status, etc.) 
will be utilized to assess interpatient variability in the PK and PK/PD relationships. 
 
Azacitidine concentrations will be determined. The PK parameters will be derived using 
non-compartmental methods. Cmax and AUC0-4h will be compared between treatment arms 
on Day 4 (azacitidine with and without APR-246) to determine the impact of APR-246 on 
azacitidine PK. 
 
 
 

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10.0 QUALITY CONTROL AND QUALITY ASSURANCE PROCEDURES 
10.1 Monitoring of the Study and Regulatory Compliance 
The project manager, or designee, will make an initiation site visit to each institution to 
review the protocol and its requirements with the Investigator(s), inspect the drug storage 
area, fully inform the Investigator of his/her responsibilities and the procedures for 
assuring adequate and correct documentation. During the course of the study, the monitor 
will make regular site visits in order to review protocol compliance, examine CRFs and 
individual 
to pertinent regulatory requirements. All CRF entries will be verified with source 
documentation.  The review of medical records will be done in a manner to assure that 
patient confidentiality is maintained. 
 
10.2 Curricula Vitae and Financial Disclosure of Investigators  
All Principal Investigators will be required to provide a current signed and dated curriculum 
vitae, a completed FDA Form 1572 and a financial disclosure statement to Theradex 
Oncology.  All Sub-investigators will be required to provide a current curriculum vitae and a 
financial disclosure statement to Theradex Oncology. 
 
10.3 Protocol Modifications 
No modification of the protocol should be implemented without the prior written approval 
Theradex Oncology). Any such changes 
potential risks, must receive prior approval by the IRB/IEC. The exception to this is where 
modifications are necessary to eliminate an immediate hazard to trial subjects, or when the 
change involves only logistical or administrative aspects of the trial (e.g. change in monitor, 
change in telephone number). Other administrative revisions which may impact the clinical 
portion of a study will be duly reported to the IRB/IEC by the Principal Investigator. 
 
10.4 Publication Policy 
The publication of the results of the study will be subject to the terms and conditions of the 
clinical trial agreement between the Sponsor and Investigators. Sponsor approval is 
required for publication of any data from this trial.  
 
 

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11.0 ETHICAL CONSIDERATIONS 
11.1 Informed Consent 
authorized representative, participating in the study. The form must be signed and dated. 
The ICF will contain all the Essential Elements of Informed Consent set forth in 21 CFR, Part 
50, the European Union Directive 2001/20/EC and its associated Detailed Guidances, 
European Union GCP Directive 2005/28/EC, the ICH Guideline for Good Clinical Practice, 
Section 4.8, and the terms of the Declaration of Helsinki (2008). Copies of the signed 
 
 
In cases incapacitated subjects are to be included, two sets of information sheets might be 
needed according to national regulations. In addition to the information given to the 
capacity to understand.  This information should include, where appropriate, a statement 
even if consent is given by the parent/legal representative. 
 
11.2 Institutional Review Board/Independent Ethics Committee (IRB/IEC) 
The study will not be initiated without approval of the appropriate IRB/IEC and compliance 
with all administrative requirements of the governing body of the institution.  This protocol, 
consent procedures, and any amendments must be approved by the IRB/IEC in compliance 
with current regulations of the FDA and the European Union as applicable and in 
accordance with ICH/GCPs. A letter of approval will be sent to the Sponsor prior to initiation 
of the study and when any subsequent modifications are made. The IRB/IEC will be kept 
informed by the Investigator, Theradex Oncology or the Sponsor, as required by national 
regulations, as to the progress of the study as well as to any serious and unexpected 
adverse events. 
 
11.3 Patient Privacy  
In order to maintain patient confidentiality, all CRFs, study reports and communications 
relating to the study will identify patients by initials and assigned patient numbers; patients 
should not be identified by name.  In accordance with local, national or federal regulations, 
the Investigator will allow the Sponsor or designee personnel access to all pertinent 
medical records in order to verify the data gathered on the CRFs and to audit the data 
collection process.  Regulatory agencies such as the US Food and Drug Administration 
(FDA) may also request access to all study records, including source documentation for 
inspection.  Clinical information will not be released without the written permission of the 
patient as outlined in the patient consent form. 
 

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12.0 DATA HANDLING AND RECORD KEEPING 
12.1 Data to be Entered Directly in the CRF 
The CRF will be the source record for the following data: None 
 
12.2 Recording of Data 
documents for the site, e.g., hospital chart, patient medical records. The Investigator will be 
responsible for the recording of all data on the CRF and for submitting the data to the 
Sponsor or their designee in a timely manner. Should any value be significantly different 
from normal, the Investigator will comment in the appropriate sections provided in the 
CRF.  
 
The Investigator will provide access to his/her original records to permit a representative 
from the Sponsor to verify the proper transcription of data. To facilitate photocopying, 
entries must be recorded legibly in black ink only.  Erroneous entries will be crossed out 
with a single line, so as to remain legible. The correct value will be entered above the error 
and then initialed and dated by the person authorized to make the correction. 
 
12.3 Study Records 
U.S. Federal laws require that an Investigator maintain all study records for the indication 
under investigation for two years following the date a Product Licensing Application is 
approved or, if no application is to be filed or if the application is not approved for such 
indication, until two years after the investigation is discontinued and the FDA is notified. 
 
 
 
 

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13.0 REFERENCES
 
1 Cheson, Bruce D., et al. "Clinical application and proposal for modification of the International 
Working Group (IWG) response criteria in myelodysplasia." Blood 108.2 (2006): 419-425. 
2 National Cancer Institute, Surveillance, Epidemiology, and End Results Program, SEER*Explorer 
Beta Release-Updated April 16, 2018.  Available at:  
https://seer.cancer.gov/explorer/application.php?site=409&data_type=1&graph_type=2&compareBy
=race&chk_sex_1=1&chk_sex_3=3&chk_sex_2=2&chk_race_1=1&chk_age_range_1=1&advopt_precisi
on=1&advopt_display=1&showDataFor=sex_1_and_age_range_1. Accessed May 9, 2018. 
3 Greenberg, P.L., et al. "Revised International Prognostic Scoring System for Myelodysplastic 
Syndromes." Blood, 120 (2012): 2454-2465. 
4 Fenaux, P., et al. on behalf of the ESMO Guidelines Working Group. Myelodysplastic syndromes: 
ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Annals of Oncology, 
Volume 25, Issue suppl_3, 1 September 2014, Pages iii57 iii69. 
5 Soussi, T, and Wiman, K.G. Shaping genetic alterations in human cancer: the p53 mutation 
paradigm. Cancer cell(2007).12:303-312. 
6 Wattel, E., et al. p53 mutations are associated with resistance to chemotherapy and short survival 
in hematologic malignancies. Blood 84(1994):3148-3157. 
7 Ling, Z., McGraw, K.L., Sallman, D.A., & List, A.F. The role of p53 in myelodysplastic syndromes and 
acute myeloid leukemia: molecular aspects and clinical implications. Leuk Lymphoma 58(8):1777-
1790 (Aug 2017). 
8 
Zwierzinq, 
H., 
et 
al. 
Low-dose 
cytosine 
arabinoside 
(LD-AraC) 
vs 
LD-AraC 
plus 
granulocyte/macrophage colony stimulating factor vs LD-AraC plus Interleukin-3 for myelodysplastic 
syndrome patients with a high risk of developing acute leukemia: final results of a randomized 
phase III study (06903) of the EORTC Leukemia Cooperative Group. Leukemia 19:1929 1933 (2005). 
9 Margulies, M., et al. Genome sequencing in microfabricated high-density picolitre reactors. Nature 
437, 376-380 (2005). 
10 Malcovati, L., et al. Diagnosis and treatment of primary myelodysplastic syndromes in adults: 
recommendations from the European LeukemiaNet. Blood 122, 2943-2964 (2013). 
11 Papaemmanuil, E., et al. Clinical and biological implications of driver mutations in myelodysplastic 
syndromes. Blood 122, 3616-3627; quiz 3699 (2013). 
12 Bejar, R., et al. Clinical effect of point mutations in myelodysplastic syndromes. The New England 
journal of medicine 364, 2496-2506 (2011). 
13 List, A., et al. Lenalidomide in the myelodysplastic syndrome with chromosome 5q deletion. The 
New England journal of medicine 355, 1456-1465 (2006). 
14 Kulasekararaj, A.G., et al. TP53 mutations in myelodysplastic syndrome are strongly correlated 
with aberrations of chromosome 5, and correlate with adverse prognosis. British journal of 
haematology 160, 660-672 (2013). 
15 Bally, C., et al. P-006 Prognostic value of TP53 gene mutations in higher-risk MDS treated with 
azacitidine (AZA). Leukemia Research 37, S25. 
16 Mallo, M., et al. Response to lenalidomide in myelodysplastic syndromes with del(5q): influence of 
cytogenetics and mutations. British journal of haematology 162, 74-86 (2013). 
 

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17 Jadersten, M., et al. TP53 mutations in low-risk myelodysplastic syndromes with del(5q) predict 
disease progression. Journal of clinical oncology : official journal of the American Society of Clinical 
Oncology 29, 1971-1979 (2011). 
18 Fenaux, P., et al. Efficacy of azacitidine compared with that of conventional care regimens in the 
treatment of higher-risk myelodysplastic syndromes: a randomised, open-label, phase III study. 
Lancet Oncol 10, 223-232 (2009). 
19 Bally, C., et al. Prognostic value of TP53 gene mutations in myelodysplastic syndromes and acute 
myeloid leukemia treated with azacitidine. Leukemia research 38, 751-755 (2014). 
20 Bejar, R., et al. TET2 mutations predict response to hypomethylating agents in myelodysplastic 
syndrome patients. Blood 124, 2705-2712 (2014). 
21 Bejar, R., et al. Somatic mutations predict poor outcome in patients with myelodysplastic 
syndrome after hematopoietic stem-cell transplantation. Journal of clinical oncology : official journal 
of the American Society of Clinical Oncology 32, 2691-2698 (2014). 
22 Montalban-Bravo, G., Takahashi, K., Garcia-Manero, G. Decitabine in TP53-Mutated AML. NEJM 
376(8): 769-797 (2017). 
23 Sallman, D.A., et al. Impact of TP53 mutation variant allele frequency on phenotype and outcomes 
in myelodysplastic syndromes. Leukemia 30, 666-673 (2016). 
24 Desoutter, J., et al. Molecular prognostic factors in acute myeloid leukemia receiving first-line 
therapy with azacitidine. Leukemia 30, 1416-1418 (2016). 
25 Bejar, R., et al. TP53 Mutation Status Divides MDS Patients with Complex Karyotypes into Distinct 
Prognostic Risk Groups: Analysis of Combined Datasets from the International Working Group for 
MDS-Molecular Prognosis Committee, (2014). 
26 Hou, H.A., et al. TP53 mutations in de novo acute myeloid leukemia patients: longitudinal follow-
ups show the mutation is stable during disease evolution. Blood cancer journal 5, e331 (2015). 
27 Lehmann S., et al. Targeting p53 in vivo: a first-in-human study with p53-targeting compound 
APR-246 in refractory hematologic malignancies and prostate cancer. J Clin Oncol. Oct 10;30(29): 
3633-3639, (2012). 
28 Deneberg S., Cherif H., Lazarevic V., Andersson PO, von Euler M., Juliusson G., Lehman S. An open-
label phase I dose-finding study of APR-246 in hematological malignancies. Blood Cancer J. Jul 
15;6(7):e477, (2016). 
29 Cardiabase. ECG Safety report, Analysis of ECGs from the phase 1b/II study APR-407 and from the 
phase II study APR-486 in patients with ovarian cancer who were treated with APR-246; 2018. Report 
No.: 2 August 2018. 
30 Product insert of Vidaza® (Azacitidine for injection), 2016 (USA). 
31 SmPC of Vidaza® (Azacitidine for injection), 2017 (EU). 
32 Rosello et al. on behalf of the ESMO Guidelines Committee; Management of infusion reactions to 
systemic anticancer therapy: ESMO Clinical Practice Guidelines; Annals of Oncology 28 (Supplement 4): 
iv100 iv118, 2017. http://www.esmo.org/Guidelines/Supportive-and-Palliative-Care/Management-of-
Infusion-Reactions-to-Systemic-Anticancer-Therapy 
33 ICH E9(R1) addendum on estimands and sensitivity analysis in clinical trials to the guideline on 
statistical principles for clinical trials. 
34 Robins, James M., and Dianne M. Finkelstein. "Correcting for noncompliance and dependent 
censoring in an AIDS clinical trial with inverse probability of censoring weighted (IPCW) log rank 
sts." Biometrics 56.3 (2000): 779-788. 
 

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35. Ramos F, Fernandez-Ferrero S, Suarez D, et al. Myelodysplastic syndrome: a search for minimal 
diagnostic criteria. Leuk Res. 1999;23:283-290 
 

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APPENDIX I  ECOG PERFORMANCE STATUS 
 
 
Grade 
 
0 
Fully active, able to carry on all pre-disease performance 
without restriction. 
 
1 
Restricted in physically strenuous activity but ambulatory and 
able to carry out work of a light or sedentary nature, e.g., light 
house work, office work. 
 
2 
Ambulatory and capable of all self-care but unable to carry 
out any work activities.  Up and about more than 50% of 
waking hours. 
 
3 
Capable of only limited self-care, confined to bed or chair 
more than 50% of waking hours. 
 
4 
Completely disabled.  Cannot carry on any self-care.  Totally 
confined to bed or chair. 
 
5 
Dead. 
 
 
 
 

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APPENDIX II 
 
PROPOSED 
MODIFIED 
INTERNATIONAL 
WORKING 
GROUP 
RESPONSE CRITERIA FOR ALTERING NATURAL HISTORY OF MDS 
(from Cheson et al, Blood 2006) 
 
Category 
Definition 
Complete remission (CR) 
normal maturation of all cell lines* 
Persistent dysplasia will be noted  
Peripheral blood   
   Hemoglobin (Hgb) 
 
   
× 109/L 
   
× 109/L   
   Blasts 0% 
Partial remission (PR) 
All 
CR 
criteria 
if 
abnormal 
before 
treatment except: 
 
over pretreatment but still > 5% 
Cellularity and morphology not relevant 
 
 
 
Peripheral blood: if HI responses, they will 
be noted in addition to marrow CR  
Stable disease 
Failure to achieve at least PR< but no 
evidence of progression for > 8 weeks 
Failure 
Death during treatment or disease 
progression characterized by worsening 
of cytopenias, increase in percentage of 
bone marrow blasts, or progression to a 
more advanced MDS FAB subtype than 
pretreatment 
Relapse after CR or PR 
At least 1 of the following: 
   Return to pretreatment bone marrow 
blast percentage 
   
remission/response levels in granulocytes 
or platelets 
   

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g/dL or transfusion dependence 
Cytogenic response 
Complete = Disappearance of the 
chromosomal abnormality without 
appearance of new ones 
 
Partial = at least 50% reduction of the 
chromosomal abnormality 
Disease progression 
For patients with:
  
blasts to > 5% blasts; 
  5-
blasts; 
  10-
blasts; 
  20-
blasts 
 
Any of the following: 
  At least 50% decrement from maximum 
remission/response in granulocytes or 
platelets 
  
 
  Transfusion dependence 
Survival 
Endpoints: 
   Overall: death from any cause 
   Event free failure or death from any 
cause 
   PFS: disease progression or death from 
MDS 
   DFS: time to relapse 
   Cause-specific death: death related to 
MDS 
Deletions to IWG response criteria are not shown. 
To convert hemoglobin from grams per deciliter to grams per liter, multiply grams per deciliter by 
10. 
* Dysplastic changes should consider the normal ranges of dysplastic changes (modification) 35 
 Modification to IWG response criteria. 
 In some circumstances, protocol therapy may require the initiation of further treatment (eg, 
consolidation, maintenance) before the 4-week period. Such patients can be included in the 
response category into which they fit at the time the therapy is started. Transient cytopenias during 
repeated chemotherapy courses should not be considered as interrupting durability of response, as 
long as they recover to the improved counts of the previous course. 
 
 

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Proposed modified IWG response criteria for hematologic improvement  
Hematologic improvement 
Response 
criteria 
(responses must last at 
least 8 weeks)  
Erythroid response (pretreatment, < 11 g/dL) 
 
Relevant reduction of units 
of RBC transfusions by an 
absolute number of at 
least 4 RBC transfusions/8 
weeks compared with the 
pretreatment transfusion 
number in the previous 8 
wk. Only RBC transfusions 
g/dL pretreatment will 
count in the RBD 
transfusion response 
evaluation  
Platelet response (pretreatment, < 100 × 109L) 
× 
109/L for patients starting 
with > 20 × 109/L and by at 
least 100%  
 
Neutrophil response (pretreatment, < 1.0 × 109/L 
At least 100% increase and 
an absolute increase > 0.5 
× 109/L  
Progression or relapse after HI  
At least 1 of the following: 
   At least 50% decrement 
from maximum response 
levels in granulocytes or 
platelets 
   
g/dL 
   Transfusion dependence 
Deletions to the IWG response criteria are not shown. 
To convert hemoglobin levels from grams per deciliter to grams per liter, multiply grams per 
deciliter by 10. 
Hgb indicates hemoglobin; RBC: red blood cell; HI: hematologic improvement. 
*Pretreatment counts averages of at least 2 measurements (not influenced by transfusions) 1 week 
apart (modification). 35 
Modification to IWG response criteria. 

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In the absence of another explanation, such as acute infection, repeated courses of chemotherapy 
(modification), gastrointestinal bleeding, hemolysis, and so forth. It is recommended that the 2 kinds 
of erythroid and platelet responses be reported overall as well as by the individual response pattern. 

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APPENDIX III  NEW YORK HEART ASSOCIATION (NYHA) CLASSIFICATION 
 
NYHA grading 
MET* 
Class I 
No limitations. Ordinary physical activity does not cause 
undue fatigue, dyspnea or palpitations (asymptomatic LV 
dysfunction) 
>7 
Class II 
Slight limitation of physical activity. Ordinary physical 
activity results in fatigue, palpitation, dyspnea or angina 
pectoris (mild CHF). 
5 
Class III 
Marked limitation of physical activity. Less than ordinary 
physical activity leads to symptoms (moderate CHF) 
2  3 
Class IV 
Unable to carry on any physical activity without discomfort. 
Symptoms of CHF present at rest (severe CHF). 
1.6 
 
*MET (metabolic equivalent) is defined as the resting VO2 for a 40-year-old 70kg man. 1 
MET = 3.5mL O2/min/kg body weight. 
 

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APPENDIX IV  COCKCROFT GAULT EQUATION 
 
 
 
 
Males: 
 
 
Creatinine  
CL (mL/min) 
= 
Weight (kg) × (140  Age)___ 
72 × serum creatinine (mg/dL) 
 
 
Females: 
 
 
Creatinine  
CL (mL/min) 
= 
Weight (kg) × (140  Age)        
× 0.85 
72 × serum creatinine (mg/dL)