A Phase 3, Interventional, Randomized, Multicenter, Open-Label Study of Ripretinib vs Sunitinib in Patients With Advanced Gastrointestinal Stromal Tumor (GIST) After Treatment With Imatinib
Phase: PHASE3
Conditions: Gastrointestinal Stromal Tumors
Sponsor: Deciphera Pharmaceuticals, LLC

Trial ID: 2618-03-002 INTRIGUE 
Document:  Protocol 
Official Title: A Phase 3, Interventional, Randomized, Multicenter, Open--label Study of DCC-2618 vs 
Sunitinib in Patients with Advanced Gastrointestinal Stromal Tumors after Treatment with Imatinib 
ClinicalTrial.gov NCT Number: NCT03673501 
 
Approval Date: 23 Oct 2020 
 
 

Clinical Study Protocol DCC-2618-03-002, Amendment 6 
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INVESTIGATOR STATEMENT 
I understand that all documentation provided to me by Deciphera Pharmaceuticals, LLC or 
its designated representative(s) concerning this study that has not been published previously 
will be kept in the strictest confidence. This documentation includes the study protocol, 
Investigator brochure, case report forms, and other scientific data. 
This study will not commence without the prior written approval of a properly constituted 
Institutional Review Board/Independent Ethics Committee/Research Ethics Board. No 
changes will be made to the study protocol without the prior written approval of Deciphera 
Pharmaceuticals, Inc. and the Institutional Review Board, except where necessary to 
eliminate an immediate hazard to the patient. 
I have read, understood, and agree to abide by all the conditions and instructions contained 
in this protocol. 
 
 
Investigator Name 
 
Investigator Signature 
 
Date 
 
 
 
 
 
 
Name of Investigational Site 

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CLINICAL STUDY SYNOPSIS 
Protocol Title: 
A Phase 3, Interventional, Randomized, Multicenter, Open-Label Study of 
DCC-2618 vs Sunitinib in Patients with Advanced Gastrointestinal Stromal 
Tumors after Treatment with Imatinib (intrigue) 
Protocol Number: 
DCC-2618-03-002 
Study Phase: 
3 
Study Centers: 
Approximately 125 centers globally 
Number of Patients 
Planned: 
426 patients  
(213 randomized to DCC-2618 and 213 randomized to sunitinib) 
Objectives: 
Primary Objectives: 
• To assess the efficacy (progression-free survival [PFS]) of DCC-2618 
by independent radiologic review in patients with advanced 
gastrointestinal stromal tumors (GIST) who have previously 
received first-line therapy with imatinib 
Key Secondary Objectives: 
• To assess objective response rate (ORR) by independent radiologic 
review using modified RECIST (mRECIST) criteria 
• To assess Overall Survival (OS) 
Other Secondary Objectives: 
• To assess the quality-of-life (QOL) during treatment as measured by: 
o EORTC QLQ-C30 
o Dermatology Life Quality Index (DLQI) 
o GP5 question from the FACT-G (burden of side-effects) 
• To assess Time to Tumor Progression (TTP) by independent 
radiologic review 
• To assess efficacy parameters, including disease control rate (DCR), 
PFS based on Investigator assessment, and efficacy based on Choi 
criteria by independent radiologic review 
• To assess the PK/PD relationship of DCC-2618 
• To compare the safety profile of DCC-2618 to the safety profile of 
sunitinib 
Exploratory Objectives: 
• To assess the QOL during treatment as measured by: 
o Memory and concentration items from the PRO-CTCAE 
library 
o EQ-5D-5L 

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4. Patients must have progressed on imatinib or have documented 
intolerance to imatinib. Imatinib treatment must have been 
discontinued 10 days prior to the first dose of study drug. All prior 
imatinib treatment will count as one line of therapy (e.g. adjuvant 
imatinib and dose escalation of imatinib). 
5. Eastern Cooperative Oncology Group (ECOG) PS of ≤ 2 at screening. 
6. Female patients of childbearing potential must have a negative serum 
beta-human chorionic gonadotrophin (β-hCG) pregnancy test at 
screening and negative pregnancy test at Cycle 1 Day 1 prior to the 
first dose of study drug. 
7. Patients of reproductive potential must agree to follow contraception 
requirements outlined in Section 6.11.9.  
8. Patients must have at least 1 measurable lesion according to mRECIST 
Version 1.1 (non-nodal lesions must be ≥ 1.0 cm in the long axis or 
≥ double the slice thickness in the long axis) within 21 days prior to 
the first dose of study drug. 
9. Adequate organ function and bone marrow reserve as indicated by the 
following central laboratory assessments performed at screening: 
a. Absolute Neutrophil Count (ANC) ≥ 1000/µL 
b. Hemoglobin ≥ 8 g/dL 
c. Platelet count ≥ 75,000/µL 
d. Total bilirubin ≤ 1.5 x the upper limit of normal (ULN) 
e. Aspartate transaminase (AST) and alanine transaminase (ALT) 
≤ 3 x ULN (≤ 5x ULN in the presence of hepatic metastases) 
f. Creatinine clearance ≥ 50 ml/min based on Cockcroft Gault 
estimation  
g. Prothrombin time (PT), international normalized ratio (INR) and 
partial thromboplastin time (PTT) ≤ 1.5 x ULN. Patients on a 
stable regimen of anticoagulant therapy for at least one month 
prior to the first dose of study drug may have PT/INR 
measurements > 1.5 x ULN if, in the opinion of the Investigator, 
the patient is suitable for the study. An adequate rationale must 
be provided to the Sponsor prior to randomization. 
10. Resolution of all toxicities from prior therapy to ≤ Grade 1 (or patient 
baseline) within 1 week prior to the first dose of study drug (excluding 
alopecia and ≤ Grade 3 clinically asymptomatic lipase, amylase, and 
creatine phosphokinase (CPK) laboratory abnormalities). 
11. The patient is capable of understanding and complying with the 
protocol and the patient has signed the informed consent document. 
Signed informed consent form (ICF) must be obtained before any 
study-specific procedures are performed and the patient must agree to 
not participate in any other interventional clinical trial while on 

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treatment in this clinical trial. Participation in a noninterventional 
study (including observational studies) is permitted. 
Exclusion Criteria 
Patients meeting any of the following criteria will be excluded from the 
study: 
1. Treatment with any other line of therapy in addition to imatinib for 
advanced GIST. Imatinib-containing combination therapy in the 
first-line setting is not allowed.  
2. Patients with a prior or concurrent malignancy whose natural 
history or treatment have the potential to interfere with the safety or 
efficacy assessment of this clinical trial are not eligible. For 
example, patients receiving adjuvant cancer treatment are not 
eligible if those medications are potentially active against GIST or 
excluded per protocol. 
NOTE: Patients with a history of breast cancer, requiring continued 
hormonal treatment (e.g. anti-estrogen or an aromatase inhibitor) 
may continue treatment. Patients with a history of prostate cancer, 
requiring continued support with luteinizing hormone-releasing 
hormone (LHRH) agonists, with or without androgens, may 
continue treatment. 
NOTE: Patients may not be part of an ongoing or have prior 
participation in an investigational drug study within 30 days of 
screening.  
3. Patient has known active central nervous system metastases. 
4. New York Heart Association class II-IV heart disease, myocardial 
infarction within 6 months of cycle 1 day 1, active ischemia or any 
other uncontrolled cardiac condition such as angina pectoris, 
clinically significant cardiac arrhythmia requiring therapy, 
uncontrolled hypertension or congestive heart failure. 
5. Left ventricular ejection fraction (LVEF) < 50% at screening. 
6. Arterial thrombotic or embolic events such as cerebrovascular 
accident (including ischemic attacks) or hemoptysis within 
6 months before the first dose of study drug. 
7. Venous thrombotic events (e.g. deep vein thrombosis) or 
pulmonary arterial events (e.g. pulmonary embolism) within 
1 month before the first dose of study drug. Patients on stable 
anticoagulation therapy for at least one month are eligible. 
8. 12-lead electrocardiogram (ECG) demonstrating QT interval 
corrected (QTc) by Fridericia's formula > 450 ms in males or 
> 470 ms in females at screening or history of long QT syndrome. 
9. Use of strong or moderate inhibitors or inducers of cytochrome 
P450 (CYP) 3A4, including certain herbal medications (e.g. St. 
John’s Wort) within 14 days or 5 x the half-life (whichever is 
longer) prior to the first dose of study drug, and consumption of 
grapefruit or grapefruit juice within 14 days prior to the first dose 

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of study drug. Please refer to the Indiana University Department of 
Medicine website (http://medicine.iupui.edu/clinpharm/ddis/main-
table/) for guidance on medications that inhibit/induce CYP3A4 
enzymes.  See Section 5.12.3.2. 
10. Use of known substrates or inhibitors of BCRP transporters within 
14 days or 5 x the half-life (whichever is longer) prior to the first 
dose of study drug. Please refer to the US Food and Drug 
Administration’s (FDA) website for inhibitors and substrates 
(https://www.fda.gov/Drugs/DevelopmentApprovalProcess/Develo
pmentResources/DrugInteractionsLabeling/ucm093664.htm).  See 
Section 5.12.3.2 
11. Major surgeries (e.g. abdominal laparotomy) within 4 weeks of the 
first dose of study drug. All major surgical wounds must be healed 
and free of infection or dehiscence before the first dose of study 
drug.  
12. Any other clinically significant comorbidities, such as uncontrolled 
pulmonary disease, active infection, or any other condition, which 
in the judgment of the Investigator, could compromise compliance 
with the protocol, interfere with interpretation of the study results, 
or predispose the patient to safety risks. 
13. Known human immunodeficiency virus or hepatitis C infection 
only if the patient is taking medications that are excluded per 
protocol (Section 5.12.3.2), active hepatitis B, or active hepatitis C 
infection. 
14. If female, the patient is pregnant or lactating. 
15. Known allergy or hypersensitivity to any component of the study 
drug. Patients with history of Stevens-Johnson syndrome on a prior 
tyrosine kinase inhibitor (TKI) are excluded.  
16. Gastrointestinal abnormalities including, but not limited to:  
a. inability to take oral medication 
b. malabsorption syndromes  
c. requirement for intravenous (IV) alimentation 
17. Any active bleeding excluding hemorrhoidal or gum bleeding. 
Study Drug: 
DCC-2618 or sunitinib 
Formulation: 
DCC-2618 tablets or sunitinib capsules 
Dose: 
DCC-2618: 150 mg QD continuous dosing for 6 week (42 days) cycles.  
Sunitinib:  50 mg QD in 6 week (42 days) cycles with 4 weeks continuous 
dosing followed by 2 week break. Dose modifications are allowed per 
approved package insert or institutional guidelines. Pharmacokinetic (PK)-
guided dosing is not allowed. Every effort should be made to continue 
patients on the starting sunitinib dose regimen throughout the first cycle, 
unless toxicity mandates dose modification.  

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Route of 
Administration: 
Oral 
Study Endpoints: 
Primary Endpoint: 
• 
PFS of DCC-2618 based on independent radiologic review using 
mRECIST criteria: 
mRECIST criteria includes: 
• 
No lymph nodes chosen as target lesions; enlarged lymph nodes 
followed as non-target lesions;  
• 
No bone lesions chosen as target lesions;   
• 
Positron emission tomography (PET) not acceptable for 
radiological evaluation; 
• 
A progressively growing new tumor nodule within a pre-existing 
tumor mass must meet the following criteria to be considered as 
unequivocal evidence of progression according to the modification 
of RECIST Version 1.1: (a) the lesion is at least 2 cm in size and 
definitively a new active GIST lesion (e.g. enhancing with contrast 
or other criteria to rule out artefact); or (b) the lesion has to be 
expanding on at least 2 sequential imaging studies. 
Key Secondary Endpoints: 
Efficacy: 
• 
ORR (confirmed complete response [CR] + confirmed partial 
response [PR]) based on independent radiologic review using 
mRECIST criteria 
• 
OS 
The primary and secondary endpoints will be analyzed for both the KIT 
Exon 11 (Exon 11 ITT) and the All Patients (AP ITT) population. 
Other Secondary Endpoints: 
• 
QOL as measured by using EORTC QLQ-C30, DLQI, and the GP5 
questions from FACT-G 
• 
TTP based on independent radiologic review 
• 
Disease control rate (DCR; CR + PR + stable disease [SD]) at 6, 9, 
and 12 months, based on independent radiologic review 
• 
PFS based on Investigator assessment 
• 
Efficacy using Choi criteria based on independent radiologic 
review 
Safety: 
• 
Treatment-emergent adverse events (TEAEs), adverse events of 
special interest (AESIs), serious adverse events (SAEs), dose 
reduction or discontinuation of study drug due to toxicity; and 
changes from baseline in ECOG PS, vital signs, ECGs, LVEF, 
dermatologic examinations, and clinical laboratory parameters. 

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Pharmacokinetics (PK): 
• 
Correlation of PK exposure with efficacy/safety 
• 
Population-based PK parameters 
Exploratory Endpoints: 
• 
QOL as measured by EQ-5D-5L, and the memory and 
concentration items from the PRO-CTCAE library 
• 
PFS2: PFS on next line of therapy based on local assessments 
• 
Subgroup analyses for efficacy and other endpoints may be 
explored as data becomes available 
o Biomarkers and Pharmacodynamics (PDs): 
 Determine the potential innate and acquired resistance 
mechanisms to DCC-2618 in GIST.  
 Assess KIT/PDGFRA mutations and mutant allele 
frequency at baseline and the treatment effect of DCC-2618 
on KIT/PDGFRA mutant allele frequency.  
o Evaluate the association of anti-tumor activity/safety of 
DCC-2618 with the following:  
 baseline KIT/PDFGRA mutation status 
 expression of KIT protein in tumor 
 expression or polymorphic variation in drug metabolic 
and/or drug transporter genes  
• 
Changes over time in healthcare utilization 
Statistical 
Considerations: 
Randomization:  426 patients will be randomized in 1:1 ratio to DCC-2618 
and sunitinib treatment arms. KIT/PDGFRA WT GIST (wild-type KIT and 
wild-type PDGFRA regardless of the mutational status of any other gene) 
will be limited to a maximum of up to 10% of the total patient population. 
Randomization into treatment groups will be stratified by:  
• 
Mutational status: KIT exon 9 mutation; KIT exon 11 mutation; 
KIT/PDGFRA WT; or other KIT (absence of exon 9 or 
11)/PDGFRA mutations  
Note: if a patient has a KIT exon 11 mutation, along with 
mutation(s) 1) in KIT exon 9 and/or PDGFRA, the patient will be 
randomized as having a KIT exon 11 mutation, unless the mutation 
allele frequency (MAF) data is available then the mutation with the 
higher MAF will be used to categorize the patient for the purposes 
of randomization; 2) in KIT other exon, the patient will be 
randomized as having a KIT exon 11 mutation.  
• 
Intolerance to imatinib (Yes or No)  
The KIT Exon 11 Intent-to-Treat (Ex11 ITT) Population is defined as all 
patients who are designated as having a mutation in KIT Exon 11 at the 

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time of randomization. Patients in this population will be analyzed 
according to the treatment they were scheduled to receive.  
The All Patients ITT (AP ITT) population is defined as all patients who are 
randomized. Patients in this population will be analyzed according to the 
treatment they were scheduled to receive.  
The primary endpoint PFS and the secondary endpoints will be analyzed in 
both Ex11 ITT and AP ITT populations. The analysis of PFS in AP ITT 
will be stratified by the randomization stratification factors (mutation status 
[KIT exon 9 vs. KIT exon 11 vs. KIT/PDGFRA WT vs. other KIT 
{absence of KIT exon 9 or 11}/PDGFRA] and intolerance to imatinib [yes 
vs. no]). Analysis for PFS in Ex11 ITT will be stratified by intolerance to 
imatinib [yes vs. no].  The p-value will be from a 2-sided stratified 
Log-rank test at 0.05 significance level for evaluation of treatment 
difference. Point estimate of hazard ratio will be obtained from a Cox 
regression model with treatment and the randomization stratification factors 
as fixed factors and the associated 95% CI will be obtained using the Wald 
method. Median progression free survival time (mPFS) with 95% 
confidence interval will also be presented by treatment using KM 
methodology. 
The Safety Population is defined as all patients who are randomized and 
receive at least one dose of study drug.  The Safety population will be used 
for all safety analysis and treatment assignment and will be based on the 
actual initial study treatment received. The safety parameters include AE, 
vital signs, laboratory results, LVEF and ECG results. 
The sample size selection of 426 patients (n=213 DCC-2618, 
n=213 sunitinib) was based on considerations for powering of the primary 
endpoint, secondary endpoints, detection of rare safety events and overall 
exposure to DCC-2618.  
Under the assumptions that mPFS is 9 months for DCC-2618 and 6 months 
for sunitinib, the HR is about 0.667 for the AP PFS (sunitinib vs 
DCC-2618). A total of 262 events will be required to achieve a statistical 
power of 90% to test the hypothesis of no difference between DCC-2618 
and sunitinib in the AP population. Accrual of 426 patients (213 in 
DCC-2618 and 213 in sunitinib) within 21 months is expected to have 
262 PFS events occurred after additional 8 months of follow up. This has 
accounted for 20% of dropout rate (discontinuation without progressive 
disease per IRR or death). 
It is further assumed that the mPFS is 9 months for Ex11 patients in 
DCC-2618 and 5 months for Ex11 patients in sunitinib, the HR is 0.556 for 
the Ex11 PFS. It is planned to perform the final analysis on both Ex11 and 
AP populations at the same time.  The final analysis is planned to occur 
when at least 151 PFS events in Ex11 population and approximately 
262 PFS events in AP population have occurred. The 151 PFS events in 
Ex11 population have at least 95% power to test the hypothesis of no 
difference between DCC-2618 and sunitinib in KIT Ex11 population. 

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Figure 1: 
Study Schema  
 
 
 
 
 
 
 

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7. 
Patients taking anticoagulants will also have a test at Cycle 1 Day 15. Monitoring of coagulation tests must be increased for as long as deemed clinically appropriate following 
a change in anticoagulant dose during the study. 
8. 
Urinalysis testing will be performed by the central laboratory at screening, on Day 1 of Cycles 1, 2, 3 and 4, and the EOT visit and as clinically indicated. If any result is 
abnormal, a microscopic analysis will be performed by the central laboratory.  
9. 
TSH, Total T3 and Total T4 testing will be performed at screening, on Day 1 of Cycle 1, Day 1 of every odd-numbered cycle (i.e. Cycle 3, Cycle 5, Cycle 7 etc.), and the 
EOT visit.  
10. ECOG PS may be performed pre- or post-dose. 
11. Vital sign measurements will be collected after the patient has been at rest (seated or supine position) for at least 5 minutes.   
12. All 12-lead ECGs will be performed after the patient has been at rest (supine or semi-recumbent position) for at least 15 minutes.  The rest period begins after the placement 
of the ECG leads. 
13. An echocardiogram or MUGA will be performed at screening, Cycle 3 Day 1, and Day 1 of every third cycle thereafter (i.e. Cycle 6, 9, 12, etc.), and the EOT visit, unless 
deemed clinically appropriate at other times. The same modality (echocardiogram or MUGA) must be used throughout the study. Echocardiogram or MUGA performed as 
standard of care prior to informed consent may be used as the screening assessment as long as the echocardiogram or MUGA was performed within 28 days prior to the first 
dose of study drug. 
14. All patients will be assessed by a consulting dermatologist at screening for skin lesions, especially for squamous cell carcinoma, actinic keratosis, and keratoacanthomas, 
within 21 days prior to Cycle 1 Day 1 (baseline). Subsequently, patients will be assessed at Cycle 3 Day 1, Day 1 of every third cycle thereafter (i.e. Cycle 6, 9, 12, etc.), the 
EOT visit and as otherwise clinically indicated.  Dermatological exam that meets the protocol criteria that was performed as standard of care prior to informed consent may be 
used as the screening assessment as long as the exam was performed within 21 days prior to the first dose of study drug. Dermatological examinations during the treatment 
phase may be performed up to 7 days prior to the corresponding study visit or post dose on the day of the study visit. See Section 6.11.6 for further details. 
15. The EORTC QLQ-C30, EQ-5D-5L, DLQI, GP5 question from FACT-G, and PRO-CTCAE Questions 46 and 47 must be performed before the patient is evaluated by the 
Investigator or designee on the day of the scheduled visit. If the dermatologic examination or imaging assessments are completed within 7 days of the scheduled visit and the 
patient is not evaluated by the Investigator or designee, the questionnaires do not need to be completed on that day. The GP5 question from FACT-G will be completed first 
followed by EORTC-QLQ-C30, DLQI, EQ-5D-5L and PRO-CTCAE Questions 46 and 47. The questionnaires will be collected via an electronic patient reported outcome 
system.  Patients will complete all questionnaires at home on Day 29 of Cycle 3 and beyond via the electronic patient report outcome system. Patient-entered data will not be 
modified by the Investigator or site staff, ePRO vendor, CRO or Sponsor. 
16. On days of study visits, patients will be informed to take the study drug at the study site after predose assessments are completed. See Section 5.3 for dosing and 
administration details. 
17. For DCC-2618 patients only, PK sampling will be performed at the following time points: Cycle 1 Day 1 pre-dose and 6 hours after dosing, Cycle 1 Day 15 pre-dose, and 
2 and 6 hours after dosing, pre-dose at Day 1 of Cycles 2, 3 and Day 1 of every other cycle thereafter (e.g. Cycle 5, 7, 9, etc.), and at the EOT Visit. All pre-dose samples must 
be collected within 60 minutes before dosing and all post-dose samples must be collected ±30 minutes of the nominal time point. An unscheduled PK sample may be taken at 
the time of onset of a new, suspected, treatment-related adverse event when requested by the Sponsor. 
18. South Korea Only: Pharmacogenomics samples will not be collected. 
19. Molecular pathology report with mutational status of KIT/PDGFRA must be available. Mutation status must be identified using a tissue based PCR/sequencing assay. 
Molecular pathology report with mutation status of KIT/PDGFRA must be provided to the Sponsor for review prior to randomization.  If the molecular pathology report is not 
available or insufficient, an archival tumor tissue sample or fresh biopsy is required for mutation status confirmation at the central laboratory prior to randomization. Specific 
instructions will be provided in the Study Reference Manual. 
 
 
 

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21. All Patients (optional): Additional tumor tissue samples may be collected at the EOT visit and/or for patients undergoing medical procedures including resection of metastases 
while on study or for patients that have disease progression if the patient consents and these samples will be used for further molecular testing of the cancer while treated with 
study drug. 
22. Radiologic imaging must be performed within 21 days prior to the first dose of study drug. Radiologic imaging performed as standard of care prior to informed consent may 
be used as the Screening assessment as long as the imaging was performed within 21 days prior to the first dose of study drug. CT scans of the pelvis, abdomen, and chest will 
be performed at screening. Subsequently, CT scans of the pelvis and abdomen will be performed at Days 1 of Cycles 2-7, and Day 1 of every odd-numbered cycle thereafter 
(e.g. Cycles 9, 11, 13 etc.) and EOT visit. A scan at the EOT visit is not required if disease progression was previously confirmed by independent radiologic review or if less 
than 28 days have passed since the last scan was performed. CT scans of the chest will only be performed subsequently, if the patient had lung metastases at screening or in 
case of lung symptoms (per the Investigator’s discretion). Radiologic imaging may be performed up to 7 days prior to the corresponding study visit or post dose at the study 
visit. Following Cycle 7 Day 1, any initial indication of a partial or complete response based on investigator assessment must be confirmed ≥ 4 weeks following initial 
response. MRI scans of the abdomen/pelvis and CT scan without contrast of the chest can be used for patients who are allergic to radiographic contrast media or at the 
Investigator's discretion based on the best interest of the patient after discussion with the Sponsor. Additionally, for patients whose local regulatory authority and/or ethics 
committee has not approved use of CT scans, MRIs may be used. For each patient, the same assessment technique must be used throughout their participation on study unless 
there is a safety risk as determined by the Investigator. Ultrasound scanning is not an acceptable substitute for CT scanning. 
Validation of No Disease Progression: If the independent radiologic reviewer validates that there is no disease progression per modified RECIST, the patient will continue to 
receive study drug. If the Investigator determines clinical progression based upon clinical deterioration and wishes to end treatment, a scan must be performed prior to 
treatment discontinuation. The scan must be submitted to for independent radiologic review. The basis for determination of progression due to clinical deterioration must be 
documented in the patient’s source documents and electronic case report form. If the Investigator’s assessment determines disease progression per modified RECIST, the 
Investigator should wait for confirmation from the independent radiologic review before discontinuing the patient from treatment. If the Investigator wishes to end treatment 
due to local progression, without confirmation of progression by independent radiographic review, or before the independent read results are available, the Investigator must 
reach out to the Sponsor Medical Monitor to discuss.  
 
 
 

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LIST OF ABBREVIATIONS 
Abbreviation 
Definition 
AE 
Adverse event 
AESI 
Adverse event of special interest 
ALT 
Alanine transaminase 
AML 
Acute myeloid leukemia 
ANC 
Absolute neutrophil count 
AP 
All Patients 
AP-ITT 
All Patients Intent to Treat 
ASM 
Aggressive systemic mastocytosis 
AST 
Aspartate transaminase 
ATP 
Adenosine triphosphate 
AUC 
Area under the concentration-time curve 
AUC0-24 
Area under the concentration-time curve during 24 hours 
β-hCG 
Beta-human chorionic gonadotropin 
BCRP 
Breast cancer resistance protein 
BID 
Twice daily 
BP 
Blood pressure 
BSEP 
Bile salt export pump 
cfDNA 
Cell-free DNA 
Cmax 
Maximum observed concentration 
CPK 
Creatine phosphokinase 
CR 
Complete response 
CT 
Computed tomography  
CTCAE 
Common Terminology Criteria for Adverse Events 
ctDNA 
Circulating tumor DNA 
CYP 
Cytochrome P450 
DCR 
Disease control rate 
DLQI 
Dermatologic life quality index 
DLT 
Dose limiting toxicity 
ECG 
Electrocardiogram 
ECOG 
Eastern Cooperative Oncology Group 
eCRF 
Electronic case report form 
EORTC 
European Organisation for Research and Treatment of Cancer 
EORTC QLQ-C30 
European Organisation for Research and Treatment of Cancer 
Quality of Life Questionnaire for Cancer 30 item 

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Abbreviation 
Definition 
EOT 
End of Treatment 
ePRO 
Electronic patient reported outcome 
EQ-VAS 
EuroQol visual analogue scale 
EQ-5D-5L 
EuroQol 5 Dimension 5 Level 
ER 
Efflux ratio 
FACIT 
Functional assessment of chronic illness therapy 
FACT-G 
Functional assessment of cancer therapy - general 
FDA 
Food and Drug Administration 
FFPE 
Formalin-Fixed Paraffin-Embedded 
FSH 
Follicle stimulating hormone 
fu 
Fraction unbound 
GCP 
Good Clinical Practice 
GI 
Gastrointestinal 
GIST 
Gastrointestinal stromal tumor 
GLP 
Good Laboratory Practice 
HCUQ 
Healthcare Utilization Questionnaire 
HDPE 
High density polyethylene 
IB 
Investigator’s Brochure 
ICF 
Informed consent form 
ICH 
International Conference on Harmonisation 
IDMC 
Independent Data Monitoring Committee 
IEC 
Independent Ethics Committee 
IC50 
Half maximal inhibitory concentration 
INR 
International normalized ratio 
IRB 
Institutional Review Board 
IRR 
Independent radiologic review 
IRT 
Interactive Response Technology 
ITT 
Intent to Treat 
IV 
Intravenous 
KM 
Kaplan-Meier 
LHRH 
Luteinizing hormone releasing hormone 
LVEF 
Left ventricular ejection fraction 
MDR1 
Multidrug resistance protein 1 
MedDRA 
Medical Dictionary for Regulatory Activities 
mPFS 
Modified progression free survival 
mRECIST 
Modified RECIST criteria 

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Abbreviation 
Definition 
MRI 
Magnetic resonance imaging 
MTD 
Maximum tolerated dose 
MUGA 
Multigated acquisition 
NADPH 
Nicotinamide adenine dinucleotide phosphate 
NCI 
National Cancer Institute 
NOAEL 
No observed adverse effect level 
OAT 
Organic anion transporter 
OCT 
Organic cation transporter 
ORR 
Objective response rate 
OS 
Overall survival 
PD 
Pharmacodynamic(s) 
PET 
Positron emission tomography 
PFS 
Progression-free survival 
PFS2 
Progression-free survival 2 
PK 
Pharmacokinetic(s) 
PP 
Per protocol 
PR 
Partial response 
PRO 
Patient reported outcomes 
PS 
Performance status 
PT 
Prothrombin time 
PTT 
Partial thromboplastin time 
QD 
Once daily 
QOL 
Quality of life 
QTc 
QT interval corrected 
QTcB 
QT interval corrected using Bazett’s formula 
QTcF 
QT interval corrected by Fridericia’s formula 
REB 
Research Ethics Board 
RECIST 
Response Evaluation Criteria in Solid Tumors 
RP2D 
Recommended Phase 2 dose 
SAE 
Serious adverse event 
SAP 
Statistical Analysis Plan 
SCC 
Squamous cell carcinoma 
SD 
Stable disease 
SJS 
Stevens Johnson syndrome 
SM 
Systemic mastocytosis 
SOC 
System organ class 

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Abbreviation 
Definition 
SUSAR 
Serious Unexpected Suspected Adverse Reaction 
TEAE 
Treatment-emergent adverse event 
TKI 
Tyrosine kinase inhibitor 
Tmax 
Time to maximum observed concentration 
TSH 
Thyroid stimulating hormone 
TTP 
Time to tumor progression 
T1/2 
Half-life 
ULN 
Upper limit of normal 
WT 
Wild type 
 
 

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TABLE OF CONTENTS 
1. 
INTRODUCTION AND RATIONALE ..................................................................... 27 
1.1. 
Introduction...................................................................................................... 27 
1.2. 
Clinical Indications........................................................................................... 29 
1.3. 
DCC-2618........................................................................................................ 29 
1.3.1. 
Nonclinical Experience ............................................................................... 29 
1.3.2. 
Clinical Experience ..................................................................................... 34 
1.4. 
Overview of Sunitinib....................................................................................... 39 
1.5. 
Rationale .......................................................................................................... 40 
1.5.1. 
Study Rationale........................................................................................... 40 
1.5.2. 
Dose, Regimen, and Treatment Duration Rationale ...................................... 41 
2. 
STUDY OBJECTIVES ............................................................................................. 46 
2.1. 
Primary Objective............................................................................................. 46 
2.2. 
Secondary Objectives ....................................................................................... 46 
2.2.1. 
Key Secondary Objectives........................................................................... 46 
2.2.2. 
Other Secondary Objectives ........................................................................ 46 
2.3. 
Exploratory Objectives ..................................................................................... 46 
3. 
STUDY DESIGN ..................................................................................................... 47 
3.1. 
Overview of Study Design ................................................................................ 47 
3.2. 
Number of Patients ........................................................................................... 47 
3.3. 
Duration of Study ............................................................................................. 47 
4. 
STUDY POPULATION............................................................................................ 48 
4.1. 
Inclusion Criteria .............................................................................................. 48 
4.2. 
Exclusion Criteria............................................................................................. 49 
5. 
STUDY DRUG ADMINISTRATION AND MANAGEMENT .................................. 51 
5.1. 
Sunitinib .......................................................................................................... 51 
5.1.1. 
Sunitinib Description .................................................................................. 51 
5.2. 
DCC-2618........................................................................................................ 51 
 
 
5.3. 
Study Drug Dose and Administration ................................................................ 51 
5.4. 
Study Drug Dose Interruption and Modification ................................................ 52 
5.4.1. 
Study Drug Dose Interruption due to Planned Medical Procedures................ 52 
5.4.2. 
DCC-2618 Interruption and Modification Due to Toxicity ............................ 52 
5.5. 
Packaging and Labeling .................................................................................... 57 
5.6. 
Study Drug Storage Conditions ......................................................................... 57 
5.7. 
Study Drug Compliance.................................................................................... 57 
5.8. 
Study Drug Accountability................................................................................ 57 
5.9. 
Disposal, Return, or Retention of Unused Study Drug........................................ 58 
5.10. 
Method of Assigning Patients to Treatment ....................................................... 58 
5.11. 
Blinding and Unblinding................................................................................... 58 
5.12. 
Prior and Concomitant Treatment and Procedures.............................................. 58 

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5.12.1. Prior Medications and Procedures................................................................ 58 
5.12.2. Prior Anticancer Medications and Procedures .............................................. 58 
5.12.3. Concomitant Medications ............................................................................ 58 
5.12.4. Concomitant Procedures.............................................................................. 60 
5.13. 
Other Precautions ............................................................................................. 60 
6. 
STUDY ASSESSMENTS ......................................................................................... 61 
6.1. 
Screening ......................................................................................................... 61 
6.2. 
Rescreening...................................................................................................... 61 
6.3. 
Treatment Period .............................................................................................. 61 
6.4. 
Follow Up ........................................................................................................ 61 
6.5. 
Lost to Follow Up............................................................................................. 61 
6.6. 
Study Assessments ........................................................................................... 61 
6.6.1. 
Timing of Assessment ................................................................................. 62 
6.7. 
Informed Consent Procedure ............................................................................. 62 
6.8. 
Assigning Patient Number ................................................................................ 62 
6.9. 
Demographics and Medical History .................................................................. 62 
6.10. 
Efficacy ........................................................................................................... 63 
6.10.1. Radiologic Imaging..................................................................................... 63 
6.10.2. Overall and PFS2 Survival Follow-Up by Phone Call................................... 64 
6.10.3. Patient Reported Outcome Measurements .................................................... 64 
6.11. 
Safety............................................................................................................... 66 
6.11.1. Physical Examinations ................................................................................ 66 
6.11.2. Eastern Cooperative Oncology Group Performance Status............................ 67 
6.11.3. Vital Signs, and Weight and Height ............................................................. 67 
6.11.4. Electrocardiograms ..................................................................................... 67 
6.11.5. Echocardiograms/Multigated Acquisition Scans ........................................... 68 
6.11.6. Dermatologic Examination .......................................................................... 68 
6.11.7. Clinical Laboratory Tests ............................................................................ 68 
6.11.8. Pregnancy Test ........................................................................................... 69 
6.11.9. Contraception and Pregnancy Avoidance Measures ...................................... 69 
6.11.10. Adverse Events ........................................................................................... 72 
6.11.11. Safety Follow Up ........................................................................................ 72 
6.12. 
Pharmacokinetics ............................................................................................. 72 
6.12.1. Sample Collection ....................................................................................... 72 
6.12.2. Sample Assessment..................................................................................... 72 
 
 
 
 
6.14. 
Pharmacogenomic Measurements ..................................................................... 73 
6.14.1. Sample Collection ....................................................................................... 73 
6.14.2. Sample Assessment..................................................................................... 73 

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6.15. 
Healthcare Utilization ....................................................................................... 74 
6.15.1. Healthcare Utilization Questionnaire (HCUQ) ............................................. 74 
7. 
ADVERSE EVENT AND SERIOUS ADVERSE EVENT DOCUMENTATION, 
SEVERITY GRADING, AND REPORTING ............................................................ 75 
7.1. 
Adverse Events ................................................................................................ 75 
7.2. 
Severity Assessment ......................................................................................... 75 
7.3. 
Causality Assessment ....................................................................................... 76 
7.4. 
Study Drug Action Taken ................................................................................. 76 
7.5. 
Adverse Event Outcome ................................................................................... 76 
7.6. 
Treatment Given............................................................................................... 77 
7.7. 
Additional Points to Consider for Adverse Events.............................................. 77 
7.7.1. 
Clinically Significant Assessments .............................................................. 77 
7.8. 
Serious Adverse Events .................................................................................... 78 
7.9. 
Adverse Events of Special Interest for Study Drug............................................. 78 
7.10. 
Adverse Event Reporting Periods ...................................................................... 78 
7.11. 
Adverse Event, Serious Adverse Event, and Adverse Event of Special Interest 
Reporting Requirements ................................................................................... 79 
7.12. 
Abuse, Misuse, Overdose, and Medication Error ............................................... 79 
8. 
WITHDRAWAL AND REPLACEMENT OF PATIENTS......................................... 81 
8.1. 
End of Treatment.............................................................................................. 81 
8.2. 
End of Study .................................................................................................... 81 
8.3. 
Replacement of Patients.................................................................................... 82 
9. 
STATISTICAL CONSIDERATIONS ....................................................................... 82 
9.1. 
Determination of Sample Size ........................................................................... 82 
9.2. 
Analysis Endpoints ........................................................................................... 82 
9.2.1. 
Primary Endpoint ........................................................................................ 82 
9.2.2. 
Key Secondary Endpoints ........................................................................... 83 
9.2.3. 
Exploratory Endpoints................................................................................. 83 
9.3. 
Populations for Analysis ................................................................................... 84 
9.4. 
Procedures for Handling Missing, Unused, and Spurious Data ........................... 85 
9.5. 
Interim Analyses .............................................................................................. 85 
9.6. 
Adjustment for Multiple Comparisons............................................................... 85 
9.7. 
Blinding ........................................................................................................... 86 
9.8. 
Statistical Methods ........................................................................................... 86 
9.8.1. 
General Methods......................................................................................... 86 
9.8.2. 
Disposition of Patients ................................................................................ 86 
9.8.3. 
Demographic and Baseline Characteristics ................................................... 86 
9.8.4. 
Extent of Exposure...................................................................................... 86 
9.8.5. 
Efficacy Analysis ........................................................................................ 87 
9.8.6. 
Safety Analysis ........................................................................................... 90 
9.8.7. 
Pharmacokinetic Analysis ........................................................................... 91 
 
 

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9.8.9. 
Pharmacogenomic Analysis......................................................................... 91 
9.8.10. Healthcare Utilization ................................................................................. 91 
9.8.11. Procedures for Reporting Deviations to Original Statistical Analysis Plan ..... 91 
10. STUDY COMMITTEES ........................................................................................... 91 
10.1. 
Independent Data Monitoring Committee .......................................................... 91 
11. QUALITY CONTROL AND QUALITY ASSURANCE ........................................... 92 
11.1. 
Study Site Monitoring Visits ............................................................................. 92 
11.2. 
Protocol Compliance ........................................................................................ 92 
12. DATA HANDLING AND RECORD KEEPING ....................................................... 93 
12.1. 
Electronic Case Report Form ............................................................................ 93 
12.2. 
Record Retention .............................................................................................. 93 
13. ETHICS ................................................................................................................... 94 
13.1. 
Ethical Conduct of the Study............................................................................. 94 
13.2. 
Patient Information and Consent ....................................................................... 94 
13.3. 
IRB/IEC/REB .................................................................................................. 94 
13.4. 
Patient Confidentiality ...................................................................................... 94 
13.5. 
Reporting of Safety Issues or Serious Breaches of the Protocol or International 
Conference on Harmonization Good Clinical Practice........................................ 95 
13.6. 
Liability and Insurance ..................................................................................... 95 
14. STUDY TERMINATION ......................................................................................... 96 
14.1. 
Criteria for Suspension or Premature Termination of the Study .......................... 96 
14.2. 
Criteria for Premature Termination or Suspension of Investigational Sites .......... 96 
14.3. 
Procedures for Premature Termination or Suspension of the Study or the Participation 
of Investigational Site(s) ................................................................................... 96 
15. PUBLICATION OF STUDY RESULTS ................................................................... 97 
16. REFERENCES ......................................................................................................... 98 
17. APPENDICES ........................................................................................................ 101 
17.1. 
Modified Response Evaluation Criteria in Solid Tumors (mRECIST)............... 101 
17.2. 
Healthcare Utilization Questionnaire ............................................................... 102 
 

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LIST OF TABLES IN THE TEXT 
Table 1: 
Schedule of Assessments .............................................................................. 14 
 
 
Table 3: 
Summary of Treatment Emergent Adverse Events (TEAE) that Occurred in 
≥ 10% GIST Patients @ 150 mg QD (n=114) ................................................ 36 
Table 4: 
Model-predicted Typical Steady-State Pharmacokinetic Exposure of DCC-2618 
and DP-5439 in Patients with Advanced Malignancies ................................... 43 
Table 5: 
Dose Reduction Steps for DCC-2618............................................................. 53 
Table 6: 
DCC-2618 Dose Modifications for Left Ventricular Systolic Dysfunction ...... 53 
Table 7: 
DCC-2618 Dose Modifications and Management of Hypertension ................. 54 
Table 8: 
DCC-2618 Dose Modifications for Dermatologic Toxicities (except Alopecia) 
and Arthralgia/Myalgia ................................................................................. 55 
Table 9: 
DCC-2618 Dose Modifications for Isolated Bilirubin Increased ..................... 56 
Table 10: 
DCC-2618 Dose Modifications for Treatment Related Adverse Events Not 
Mentioned Above ......................................................................................... 56 
Table 11: 
Safety Laboratory Tests ................................................................................ 69 
Table 12: 
Severity Grading Scale.................................................................................. 75 
Table 13: 
Relationship to Study Drug Criteria ............................................................... 76 
Table 14: 
Classification for Study Drug Action Taken with Regard to an Adverse Event 76 
Table 15: 
Classifications for Outcome of an Adverse Event........................................... 77 
Table 16: 
Partial or Missing Date Algorithms ............................................................... 85 
 
LIST OF FIGURES IN THE TEXT 
Figure 1: 
Study Schema ............................................................................................... 13 
Figure 2: 
Multiple Secondary KIT Mutations in Gastrointestinal Stromal Tumor Patients 
Span Exon Regions 13-18 ............................................................................. 28 
Figure 3: 
KIT Mutations in Baseline ctDNA (n=95) in 131 GIST Patients by Line of 
Therapy ........................................................................................................ 37 
Figure 4: 
Waterfall Plot of All KIT/PDGFRA 2nd/3rd Line GIST Patients ≥ 100 mg QD 
(Best Response per RECIST, N = 54) ............................................................ 38 
Figure 5: 
Spaghetti Plots for Disease Control Rate for all 2nd/3rd Line GIST ≥ 100 mg QD 
Patients (N=54) ............................................................................................ 39 
Figure 6: 
DCC-2618 Inhibition of PDGFRA and KIT Mutants...................................... 42 
Figure 7: 
Pharmacokinetic Model of DCC-2618 and DP-5439 in Patients with Advanced 
Malignancies ................................................................................................ 43 
 

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1. 
INTRODUCTION AND RATIONALE 
1.1. 
Introduction 
Activating mutations in the receptor tyrosine kinases KIT or PDGFRA have been identified in 
multiple cancer types such as gastrointestinal stromal tumors (GIST), subsets of melanoma, 
testicular seminomas and acute myeloid leukemia (AML), and in myeloproliferative neoplasms 
such as systemic mastocytosis (SM) that include aggressive SM (ASM) and mast cell leukemia 
(1, 2, 3, 4, 5). In addition, aberrant wild type KIT and/or PDGFRA overexpression is found in 
GIST, melanoma, AML, gliomas and neuroendocrine tumors (6, 7, 8, 9). 
Most GISTs are driven by activating mutations in KIT (~80%) or the related PDGFRA (~10%) 
receptor tyrosine kinases (11, 36). In GIST patients at presentation, mutations in the KIT gene 
are usually found in exon 9 or 11. Primary mutations in exon 11 disrupt the auto-inhibited form 
of the kinase, and those in exon 9 increase receptor dimerization. Both mechanisms cause ligand-
independent receptor activation, which leads to uncontrolled cell growth and transformation. 
Several KIT-targeted therapies have been approved for the treatment of GIST, but there are 
limitations to their therapeutic success.  
Upon treatment with targeted therapies, secondary resistance mutations in KIT usually arise in 
the catalytic domain of the kinase, and frequently these mutations map to the embedded 
conformational switch control mechanism that regulates KIT activity (Figure 2). Secondary 
mutations in KIT typically occur in exons 13 and 14 (near the adenosine triphosphate 
(ATP)-binding pocket) that sterically disrupt drug binding or conformationally activate KIT, and 
in the activation loop (conformation-controlling switch) encoded by exons 17 and 18 (10, 11). 
Activation loop mutations act by shifting the kinase into an activated conformation that is less 
amenable to drug binding by any of the approved therapies (12). Other diseases that have 
primary mutations in the KIT (or PDGFRA) activation loop include SM, AML, and 
PDGFRA-driven GIST (6, 13, 14). 

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Figure 2: 
Multiple Secondary KIT Mutations in Gastrointestinal Stromal Tumor 
Patients Span Exon Regions 13-18 
 
Source: Liegl B, Kepten I, Le C, Zhu M, Demetri GD, Heinrich MC, et al. Heterogeneity of kinase inhibitor resistance 
mechanisms in GIST, J. Pathol. 2008 Sep;216(1):64-74. 
Imatinib was the first KIT inhibitor approved as a therapy for advanced GIST in 2002 (15). 
Imatinib therapy is usually not curative in unresectable and/or metastatic disease with complete 
responses (CRs) seen in ~5% of patients and an objective response rate (ORR) of 68% (16). 
More than 80% of GIST patients will receive clinical benefit from imatinib monotherapy, but as 
development of imatinib-resistance is essentially inevitable, more than half will develop 
progressive disease by 2 years (17). Progression is largely due to secondary mutations in the KIT 
kinase domain that cause resistance to imatinib (11). Although imatinib is effective against exon 
11 mutations in KIT, and has some efficacy against exon 9 mutations when the dose is increased 
to 800 mg, little to no response to imatinib is seen for other mutations in KIT and PDGFRA, 
particularly those that mediate the conformational dynamics of switch activation (17, 18). 
Sunitinib was approved in 2006 as a second-line therapy for GIST patients who had disease 
progression on or intolerance to imatinib. Sunitinib has greater activity against exon 9 mutations 
compared to imatinib and less activity against exon 11 mutations (14, 17). Additionally, sunitinib 
shows activity against KIT exon 13 and 14 mutations, but only half the patients show benefit and 
median progression-free survival (PFS) is 5.5 months (17). Sunitinib is not effective against KIT 
exon 17/18 and PDGFRA exon 18 activation loop mutations.  
Regorafenib was approved in 2013 as a third-line therapy for adult patients with metastatic 
and/or unresectable GIST who have had disease progression on or intolerance to imatinib and 
sunitinib treatment. In addition to being active against KIT exon 11 mutations, regorafenib is the 
only approved therapy with activity against a subset of exon 17 mutations in KIT and for patients 
who respond, PFS approaches 5 months. Some patients present with mutations in KIT that are 
not effectively treated by regorafenib, and additionally, other or multiple secondary mutations 
arise and cause resistance to therapy (11). Tumor heterogeneity has been found with multiple 
secondary mutations in KIT arising within an individual patient in different areas of 1 tumor or 
distinct sites of metastasis (11).  

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placebo-controlled study in patients with advanced GIST who have received at least 3 prior lines 
of therapy. 
The other ongoing study is a Phase 1 Clinical Study, DCC-2618-01-001, which was initiated in 
November 2015. This is an open label, first-in-human, dose escalation study in patients with 
advanced malignancies with a molecular rationale for activity. This study has 2 parts: (1) Dose 
Escalation Phase and (2) Expansion Phase. In the Escalation Phase, daily doses of 20 mg to 
200 mg BID and 100 to 250 mg QD were given in 28 day cycles. DCC-2618 up to 400mg a day 
did not result in a dose limiting toxicity (DLT) or maximum tolerated dose (MTD) dose level, 
and 150 mg QD was selected as the recommended phase 2 dose (RP2D) based on PK, PD, 
efficacy and safety observed across the dose escalation cohorts. The Expansion Phase is 
currently enrolling 6 cohorts (3 of these are GIST) and patients in these cohorts are receiving the 
RP2D of 150 mg QD of DCC-2618. Tumor assessments are every 2 months, per local 
assessment. Major eligibility criteria include advanced refractory cancers (KIT/PDGFRA 
mutated) with a focus on GIST, Eastern Cooperative Oncology Group (ECOG) 0-2, and 
adequate end organ function. Prior treatment with KIT/PDGFRA inhibitors is allowed. More 
than 100 GIST patients have received the RP2D across dose escalation and expansion in the 
Phase 1 Clinical Study. 
1.3.2.1. 
Clinical Safety 
This section presents clinical safety data for patients that have been enrolled in the Phase 1 
Clinical Study of DCC-2618 (DCC-2618-01-001) as of April 18, 2018. Since Study 
DCC-2618-01-001 is ongoing, some of the clinical data may not be source verified or validated 
and are therefore subject to change.  Please refer to the current version of the IB for additional 
information.    
As of April 18, 2018, 194 patients were treated with DCC-2618, and of those, 100 are still 
ongoing in the study. Of the 194 patients, 38 patients had non-GIST cancers, and 156 patients 
had a diagnosis of advanced GIST. The safety data of GIST patients treated at the RP2D/Phase 3 
dose of 150mg QD (N=114), is presented in Table 3 below (treatment emergent adverse events 
[TEAEs] in ≥ 10% GIST patients treated at 150 mg QD). Overall DCC-2618 has been well-
tolerated, with very few treatment-related severe adverse events (SAEs) and Grade 3/4 events.  
As depicted in Table 3, of the 114 patients with advanced GIST treated at 150 mg QD, 
21 patients (18.4%) have had a lipase elevation. Eleven of these were Grade 3-4. Similarly, out 
of 155 GIST patients in the overall Phase 1 study safety population, 33 (21.3%) of patients had a 
lipase elevation, 17 with G3-4 (11%). Of all 194 patients treated with DCC-2618 in Phase 1, 
only two patients have presented with elevated lipase and concomitant signs or symptoms of 
pancreatitis (abdominal pain, nausea and/or vomiting). Computed tomography (CT) imaging of 
pancreas was normal in one patient, and slightly thickened/inflamed in the other. Both patients 
had DCC-2618 interrupted, then shortly after restarted (one patient at a reduced dose), with no 
recurrent signs or symptoms of pancreatitis. Based on our safety data and experience in 
194 patients treated with DCC-2618, the Sponsor does not recommend dose interruption with 
asymptomatic Grade 3 or 4 elevations of lipase. Continuation of dosing with monitoring for 
signs or symptoms of pancreatitis is recommended as described in Table 10. Patients are eligible 
for all current DCC-2618 studies with asymptomatic increases in lipase of ≤ Grade 3, as isolated 
elevations of serum pancreatic enzymes can be seen with other tyrosine kinase inhibitors. 
Not captured in Table 3, is a Grade 3 (severe) SAE of Stevens-Johnson syndrome 
(SJS)/hypersensitivity reaction. The event was reported as SJS in a 38-year-old Asian female 10 
days following the initiation of ripretinib in the Phase I (FIH) study. After a positive re-challenge 

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at a reduced dose, the study treatment was permanently discontinued due to the event and the 
event resolved on Day 51 of the study. A Grade 3 SJS corresponds to skin sloughing covering 
<10% of body surface area. It was considered related to DCC-2618. If a patient experiences 
SJS/hypersensitivity reaction while being treated with DCC-2618, DCC-2618 must be 
permanently discontinued. 
Table 3: 
Summary of Treatment Emergent Adverse Events (TEAE) that Occurred in 
≥ 10% GIST Patients @ 150 mg QD (n=114) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1.3.2.1.1. 
Deaths 
As of April 18, 2018, 19 patients were discontinued from the study due to death. Seven of these 
patients had non-GIST cancer, and 12 GIST. None of the deaths were considered related to study 
drug. 
1.3.2.1.2. 
Adverse Events of Special Interest 
As of 18 April 2018, adverse events of special interest (AESIs) included squamous cell 
carcinoma (SCC), actinic keratosis, and keratoacanthoma. These events are of special interest 
because it is unclear if these events are related to DCC-2618. Early in the phase 1 study, DCC-
2618-01-001, patients did not receive a baseline dermatologic assessment and had confounding 
factors that may have contributed to the occurrence of these events. Patients now receive 
baseline dermatologic assessments for all DCC-2618 studies, and during this study will also have 
scheduled dermatologic exams.  
1.3.2.2. 
Clinical Pharmacokinetics and Pharmacodynamic Markers 
Nonclinical studies had identified DP-5439 as an active metabolite of DCC-2618 with similar 
activity profile to its parent compound. 

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The long plasma T1/2 of the metabolite (30-60 hours) suggests that QD dosing is feasible. The 
food effect sub-study has shown that taking DCC-2618 with food should not have a negative 
impact on absorption. See Section 1.5.2 for further details on the dose, regimen, and treatment 
duration rationale for the present study. 
DCC-2618 leads to rapid clearance of a broad spectrum of KIT mutations from plasma DNA in 
patients with heavily pretreated GIST. Overall, a high total plasma concentration, determined as 
CEMEX, was observed exceeding 5 am (3,000 ng/mL) starting at 100 mg BID at Cycle 1 Day 15; 
the observed mean exposure exceeds targeted plasma levels by far, including exposures required 
for inhibition of the KIT mutations least sensitive to DCC-2618 (V654A and T670I). 
Next-generation sequencing of plasma cell-free DNA (cfDNA) was performed during the Phase 
1 study for GIST patients at baseline, every 2 cycles, while a patient was on study, and at the end 
of study (Figure 3). Mutations were detected and quantitated by Guardant 360 v2.9 or v2.10. 
Based on preliminary data (cut-off April 18th, 2018), circulating tumor DNA (ctDNA) was 
detected in the majority of baseline cfDNA. Mutations in KIT gene across exons 9, 11, 13, 14, 
17, and 18 were detected in 95/131 patients with KIT-mutant GIST using baseline ctDNA 
(Figure 3). The PDGFRA exon 18 mutations were detected in only 2 ctDNA samples out of 9 
PDGFRA exon 18 mutant patients enrolled (confirmed by archival tissue testing if tissue was 
available).  
Figure 3: 
KIT Mutations in Baseline ctDNA (n=95) in 131 GIST Patients by Line of 
Therapy 
 
Each column represents an individual GIST patient. Each filled entry on rows indicates detection of one or more 
mutations in Exon 9, 11, 13, 14, 17 and 18 of KIT gene. In pts where a KIT exon 9/11 mutation was detected in 
baseline ctDNA, secondary KIT mutations in exon 13, 14 ,17 and 18 were found across 2nd to ≥ 4th line pts. 
 
1.3.2.3. 
Clinical Efficacy  
This section presents clinical efficacy data for patients that have been enrolled as of April 18, 
2018, in the Phase 1 Study. Since Study DCC-2618-01-001 is ongoing, some of the clinical data 
may not be source verified or validated and are therefore subject to change. Please refer to the 
current version of the IB for additional information.   
In the Phase 1 study as of April 18, 2018, 25 of the 156 GIST patients have received 1 prior 
therapy (i.e. 2nd Line GIST patients) and 29 patients have received 2 prior therapies (i.e. 3rd Line 

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GIST). All efficacy data uses RECIST 1.1 Criteria with data reported as investigator assessment 
of scans. For patients at ≥ 100 mg QD with RECIST assessments (n=145), the DCR at 3 months 
for 2nd line patients is 79%, and for 3rd line patients is 82% with an ORR of 24% for 2nd and 3rd 
line patients. For ≥ 4th line patients dosed ≥ 100 mg QD (N=91), the DCR is 64% with an ORR 
of 9% (31). The waterfall plot of best response of KIT/PDGFRA 2nd and 3rd line GIST patients 
dosed at ≥ 100 mg QD is presented in Figure 4. Figure 4 also presents the baseline ctDNA 
mutation profile in 2nd line patients previously treated with imatinib, and 3rd line patients 
previously treated with imatinib and sunitinib. 
The Spaghetti Plot of 2nd and 3rd line patients at ≥ 100 mg QD is represented in Figure 5, noting 
that closed circles are patients still on treatment with DCC-2618.  
Figure 4: 
Waterfall Plot of All KIT/PDGFRA 2nd/3rd Line GIST Patients ≥ 100 mg QD 
(Best Response per RECIST, N = 54) 
 
 

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Figure 5: 
Spaghetti Plots for Disease Control Rate for all 2nd/3rd Line GIST ≥ 100 mg 
QD Patients (N=54) 
 
 
1.4. 
Overview of Sunitinib 
Sunitinib is a small molecule that inhibits multiple receptor tyrosine kinases (RTKs), some of 
which are implicated in tumor growth, pathologic angiogenesis, and metastatic progression of 
cancer. Sunitinib was evaluated for its inhibitory activity against a variety of kinases 
(> 80 kinases) and was identified as an inhibitor of platelet-derived growth factor receptors 
(PDGFRα and PDGFRβ), vascular endothelial growth factor receptors (VEGFR1, VEGFR2, and 
VEGFR3), stem cell factor receptor (KIT), FMS-like tyrosine kinase-3 (FLT3), colony 
stimulating factor receptor Type 1 (CSF-1R), and the glial cell-line derived neurotrophic factor 
receptor (RET). Sunitinib inhibition of the activity of these RTKs has been demonstrated in 
biochemical and cellular assays, and inhibition of function has been demonstrated in cell 
proliferation assays. The primary metabolite exhibits similar potency compared to sunitinib in 
biochemical and cellular assays. 
Sunitinib inhibited the phosphorylation of multiple RTKs (PDGFRβ, VEGFR2, KIT) in tumor 
xenografts expressing RTK targets in vivo and demonstrated inhibition of tumor growth or tumor 
regression and/or inhibited metastases in some experimental models of cancer. Sunitinib 
demonstrated the ability to inhibit growth of tumor cells expressing dysregulated target RTKs 
(PDGFR, RET, or KIT) in vitro and to inhibit PDGFRβ- and VEGFR2-dependent tumor 
angiogenesis in vivo. 
The recommended dose of SUTENT for gastrointestinal stromal tumor (GIST) and advanced 
renal cell carcinoma is one 50 mg oral dose taken QD, on a schedule of 4 weeks on treatment 
followed by 2 weeks off (Schedule 4/2). SUTENT may be taken with or without food. 
Study NCT#00075218 was a 2-arm, international, randomized, double-blind, placebo-controlled 
trial of SUTENT in patients with GIST who had disease progression during prior imatinib 
mesylate (imatinib) treatment or who were intolerant of imatinib. The objective was to compare 

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time to tumor progression (TTP) in patients receiving SUTENT plus best supportive care versus 
patients receiving placebo plus best supportive care. Other objectives included PFS, ORR, and 
overall survival (OS). Patients were randomized (2:1) to receive either 50 mg SUTENT or 
placebo orally, QD, on Schedule 4/2 until disease progression or withdrawal from the study for 
another reason. Treatment was unblinded at the time of disease progression. Patients randomized 
to placebo were then offered crossover to open-label SUTENT and patients randomized to 
SUTENT were permitted to continue treatment per investigator judgment. In the double-blinded 
treatment phase, median TTP was 27.3 weeks in the SUTENT group and 6.4 weeks in the 
placebo group. Median PFS was 24.1 weeks in the SUTENT group and 6. 0 weeks in the placebo 
group. 
1.5. 
Rationale 
1.5.1. 
Study Rationale 
GISTs are predominantly driven by activating mutations in KIT (~80%) or the related PDGFRA 
(~10%) receptor tyrosine kinases (11, 36). In GIST patients at presentation, mutations in the KIT 
gene are usually found in exon 9 or 11. Imatinib as first-line therapy is usually not curative in 
unresectable and/or metastatic disease with CRs seen in ~5% of patients and an ORR of 68% 
(16). More than 80% of GIST patients will receive clinical benefit from imatinib monotherapy, 
but as development of imatinib resistance is essentially inevitable, more than half will develop 
progressive disease by 2 years (17). Progression is largely due to secondary mutations in the KIT 
kinase domain that cause resistance to imatinib (11). Although imatinib is effective against 
exon11 mutations in KIT and has some efficacy against exon 9 mutations when the dose is 
increased to 800 mg, little to no response to imatinib is seen for other mutations in KIT and 
PDGFRA, particularly those that mediate the conformational dynamics of switch activation (17, 
18). 
Sunitinib was approved in 2006 in the US as a second-line therapy for GIST patients who had 
disease progression on or intolerance to imatinib. Sunitinib has greater activity against exon 9 
mutations compared to imatinib and less activity against exon 11 mutations (14, 17). 
Additionally, sunitinib shows activity against the secondary KIT exon 13 and 14 mutations, but 
only half the patients show benefit and median PFS is 5.5 months (17). Sunitinib is not effective 
against KIT exon 17/18 secondary mutations, and not effective against PDGFRA exon 18 
activation loop mutations. 
DCC-2618 is an orally administered inhibitor of KIT and PDGFRA kinases. DCC-2618 
comprehensively and potently inhibits a broad range of primary and secondary mutants of KIT 
and PDGFRA kinases, including KIT primary initiating mutations in exons 9 and 11 and 
secondary mutations in exons 13 and 14 of the KIT Switch Pocket region and in exons 17 and 18 
of the activation loop conformation controlling Switch; and for PDGFRA the primary exon 18 
mutation D842V in the conformation controlling Switch and exon 14 mutations in the PDGFRA 
Switch Pocket. DCC-2618 also inhibits the non-mutated, (native) wild-type KIT. DCC-2618 
exhibits this broad profile of wild-type (native) and mutant KIT/PDGFRA inhibition by binding 
as an advanced Type II kinase inhibitor that penetrates the embedded KIT/PDGFRA Switch 
Pocket. DCC-2618 has the potential to provide benefit to patients with all primary mutations, 
including those not responding to imatinib inhibition, and the broad spectrum of resistance 
mutations. In the absence of KIT/PDGFRA mutation (WT GIST), the KIT protein is known to be 
strongly activated in GIST. In imatinib-resistant GISTs, KIT also continues to be expressed 
strongly (29, 30). These findings indicate that KIT plays an essential role in the pathogenesis of 
GIST. 

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DCC-2618 has shown encouraging preliminary clinical activity in patients with advanced GIST 
in the phase 1 study DCC-2618-01-001. Patients treated at ≥ 100 mg QD had a DCR at 3 months 
of 79% in 2nd line (N=25), 82% in 3rd line (N=29) and 64% in ≥ 4th line (N=91) of therapy. ORR 
was 24% in 2nd and 3rd line GIST patients and 9% in ≥ 4th line. The distribution of resistance 
mutations in KIT across exons 13, 14, 17 and 18 or a combination thereof was found to be 
similar in 2nd, 3rd and 4th line patients in the Phase 1 study (31), supporting the need of broad 
mutational coverage in all post-imatinib lines of therapy. 
Based on the broad mutational coverage of DCC-2618 in primary and secondary KIT and 
PDGFRA mutants in KIT exons 9, 11, 13, 14, 17, and 18 and PDGFRA exons 12, 14, and 18, 
wild type KIT and wild type PDGFRA as well as the manageable toxicity profile and promising 
efficacy data in the ongoing Phase 1 study, the Sponsor will be initiating this Phase 3 study 
(intrigue) to study the efficacy of DCC-2618 in patients with GIST previously treated with 
imatinib. This study is a 2-arm, randomized, open-label, international, multicenter study 
comparing the efficacy of DCC-2618 to sunitinib in patients with GIST who progressed on or 
were intolerant of imatinib. 
1.5.2. 
Dose, Regimen, and Treatment Duration Rationale 
1.5.2.1. 
Nonclinical Pharmacology and Clinical Pharmacokinetic Analyses to 
Support Optimal Phase 3 Dose Selection 
This section addresses the scientific justification for the selection of a 150 mg QD dose regimen 
for the Phase 3 studies of DCC-2618 in patients with advanced GIST. The dose recommendation 
is based on nonclinical pharmacology, clinical PK assessment, and PD results of the ongoing 
Phase 1 study (up to 18 April 2018). Upon completion of the Phase 1 study, clinical PK analysis 
and evaluation of the exposure-response relationship shall be updated. 
1.5.2.1.1. 
In Vitro Pharmacology 
The in vitro pharmacology studies demonstrated DCC-2618 and its active metabolite DP-5439 
potently inhibit wild-type and oncogenic KIT and PDGFRA variants with IC50 values in the 
range of 3-36 nM (Figure 6). Data for the currently available KIT inhibitors, imatinib, sunitinib, 
regorafenib, midostaurin and BLU-285 are shown for reference. At relevant cellular levels of 
ATP (1 mM), DCC-2618 broadly inhibits KIT mutants in exons 11, 13, 14, and 17, and a 
PDGFRA exon 18 mutant. Other Type II inhibitors do not block exon 17 mutants such as D816V 
KIT, whereas Type I inhibitors have weaker activity for exon 13/14 mutants.  

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From in vivo pharmacology studies, the target PK exposure for tumor growth inhibition was 
determined to be 10,000 ng⋅h/mL for AUC0-24hr of DCC-2618 and DP-5439 at steady-state. 
1.5.2.1.3. 
Clinical Pharmacokinetics Assessment 
A population PK analysis was performed on pooled BID and QD data collected from the 
ongoing Phase 1 study of DCC-2618 in patients with advanced malignancies 
(Protocol DCC-2618-01-001). The model structure is shown in Figure 7. The PK profiles of 
DCC-2618 and DP-5439 are both described by two-compartment models. Depot represents the 
GI tract for orally administered DCC-2618. KA is the first-order absorption rate constant of 
DCC-2618 and K23 is the first-order rate constant for the metabolism of DCC-2618 to its active 
metabolite DP-5439 by CYP3A4/5. CL and CLM represent the clearance of DCC-2618 by other 
enzymatic pathways and the clearance of DP-5439, respectively. To avoid overparameterization, 
the central and peripheral distribution volumes of DP-5439 were assumed to be the same as those 
of DCC-2618. 
Figure 7: 
Pharmacokinetic Model of DCC-2618 and DP-5439 in Patients with 
Advanced Malignancies 
 
Despite the small number of patients in each cohort, population analysis of pooled data across 
BID and QD cohorts (n=44 total) indicated dose-proportional PK for both DCC-2618 and DP-
5439 in cancer patients. The model-predicted steady-state PK exposure is shown in Table 4. 
Table 4: 
Model-predicted Typical Steady-State Pharmacokinetic Exposure of 
DCC-2618 and DP-5439 in Patients with Advanced Malignancies 
Dosing 
Interval 
Dose 
Analyte 
Ctrough (ng/mL) 
Cmax (ng/mL) 
AUC0-24hr 
(ng⋅h/mL) 
BID 
20 
DCC-2618 
131 
171 
3736 
DP-5439 
207 
225 
5211 
Combined 
338 
396 
8947 
30 
DCC-2618 
197 
257 
5603 
DP-5439 
310 
337 
7816 
Combined 
507 
594 
13419 
50 
DCC-2618 
328 
428 
9339 
DP-5439 
517 
561 
13027 
Combined 
845 
989 
22366 
100 
DCC-2618 
655 
857 
18678 
DP-5439 
1034 
1123 
26054 
Combined 
1689 
1980 
44732 

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Dosing 
Interval 
Dose 
Analyte 
Ctrough (ng/mL) 
Cmax (ng/mL) 
AUC0-24hr 
(ng⋅h/mL) 
150 
DCC-2618 
983 
1285 
28017 
DP-5439 
1551 
1684 
39081 
Combined 
2534 
2969 
67098 
200 
DCC-2618 
1311 
1714 
37356 
DP-5439 
2068 
2246 
52108 
Combined 
3379 
3960 
89464 
QD 
100 
DCC-2618 
249 
510 
9348 
DP-5439 
457 
609 
13041 
Combined 
706 
1119 
22389 
150 
DCC-2618 
373 
766 
14021 
DP-5439 
685 
914 
19562 
Combined 
1058 
1680 
33583 
Ctrough=concentration at the end of a dosing interval; Cmax=maximum concentration; AUC0-24hr=area under the 
concentration × time curve from 0 to 24 hours; BID=twice daily; QD=once daily 
 
The population PK analysis indicated that at DCC-2618 dose regimens of 30-200 mg BID or 
100-150 mg QD in a typical cancer patient, the combined steady-state PK exposure (AUC0-24hr) 
of DCC-2618 and DP-5439 exceeds the 10,000 ng⋅h/mL threshold for efficacy identified from 
xenograft mouse studies. However, the observed PK of both DCC-2618 and DP-5439 were 
highly variable among patients.  
Using the population PK model, a simulation was conducted based on 100 clinical studies, each 
including 100 patients, in order to estimate the proportion of patients achieving the 
10,000 ng⋅h/mL threshold for efficacy. Results showed that a dose of 150 mg QD (estimated 
from comparative in vitro pharmacology) is predicted to maintain the PK exposure above 10,000 
ng⋅h/mL in 93.6% of patients. The simulation was repeated with a dose of 100 mg QD, at which 
87.9% of patients are predicted to reach the efficacy threshold. 
1.5.2.1.4. 
Summary 
An oral QD dose of 150 mg DCC-2618 is recommended as the optimal dose regimen for the 
treatment of GIST based on the following considerations: 
• Comparison of in vitro pharmacological properties of DCC-2618 and 3 approved targeted 
therapies for GIST suggests an efficacious daily dose of ≤ 160 mg for DCC-2618 in patients 
with GIST 
• In vivo pharmacology studies in xenograft mouse models indicated a target combined PK 
exposure (AUC0-24hr =10,000 ng⋅h/mL) of DCC-2618 and DP-5439 for tumor growth 
inhibition. A daily oral dose of 150 mg is predicted to maintain the PK above this threshold 
in 93.6% of patients. 
• Both in vitro and in vivo pharmacology data are consistent in predicting that 150 mg QD will 
be an efficacious dose. 
• Safety data collected from the Phase 1 study support administration of 150 mg QD as a 
tolerable dose. 
Further points of consideration are listed below: 
• Comparing with BID regimens that are predicted to achieve the exposure target for efficacy, 
daily dosing is more convenient and may improve treatment adherence. Therefore, the 
150 mg QD regimen is preferred over a similar daily dose given BID. 

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• Due to the large PK interindividual variability, doses lower than 150 mg will result in PK 
exposure falling below the efficacy threshold in more patients. On the other hand, further 
improvement in efficacy is unlikely at a higher dose.  
• A dose of 100 mg QD is predicted to reach the exposure target for efficacy in a large 
majority (87.9%) of patients. If individual patients experience lack of tolerance at 
150 mg QD, the dose could be lowered to 100 mg QD potentially without compromising 
efficacy.  
• Further PK-efficacy and PK-safety assessments are being conducted to confirm the selection 
of 150 mg QD as the optimal regimen for DCC-2618 in patients with GIST. 

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2. 
STUDY OBJECTIVES 
2.1. 
Primary Objective 
• 
To assess the efficacy (progression-free survival [PFS]) of DCC-2618 by independent 
radiologic review in patients with advanced gastrointestinal stromal tumors (GIST) who 
have previously received first-line therapy with imatinib  
2.2. 
Secondary Objectives 
2.2.1. 
Key Secondary Objectives 
• To assess objective response rate (ORR) by independent radiologic review using 
mRECIST criteria 
• To assess Overall Survival (OS)  
2.2.2. 
Other Secondary Objectives 
• To assess the quality-of-life (QOL) during treatment as measured by: 
o EORTC QLQ-C30 
o Dermatology Life Quality Index (DLQI) 
o GP5 question from the FACT-G (burden of side-effects) 
• To assess Time to Tumor Progression (TTP) by independent radiologic review 
• To assess efficacy parameters, including disease control rate (DCR), PFS based on 
Investigator assessment, and efficacy based on Choi criteria by independent radiologic 
review 
• To assess the PK/PD relationship of DCC-2618 
• To compare the safety profile of DCC-2618 to the safety profile of sunitinib 
2.3. 
Exploratory Objectives 
• To assess QOL during treatment as measured by: 
o Memory and concentration items from the PRO-CTCAE library 
o EQ-5D-5L 
• To assess Progression Free Survival on next line therapy (PFS2) based on local 
assessments 
• To evaluate potential biomarkers in blood or tumor tissue which might predict response 
to DCC-2618 
o To understand potential resistance mechanisms to DCC-2618 in GIST 
o To characterize KIT and PDGFRA mutations at baseline and DCC-2618-driven 
longitudinal mutant allele frequency changes in plasma.  
• To assess healthcare utilization 

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3. 
STUDY DESIGN 
3.1. 
Overview of Study Design 
This is a 2-arm, randomized, open-label, international, multicenter study comparing the efficacy 
of DCC-2618 to sunitinib in GIST patients who progressed on or were intolerant to first-line 
anticancer treatment with imatinib.  
Approximately 426 patients will be randomized in a 1:1 ratio to DCC-2618 150 mg QD or 
sunitinib 50 mg QD, 4 weeks on, 2 weeks off (see Figure 1). Up to 10% of patients randomized 
may have KIT/PDGFRA WT GIST (wild-type KIT and wild-type PDGFRA regardless of the 
mutational status of any other gene).  Randomization will be stratified by: 
• Mutational Status: KIT exon 9 mutation; KIT exon 11 mutation; KIT/PDGFRA WT; or 
other KIT (absence of exon 9 or 11)/PDGFRA mutations 
• Intolerance to imatinib (Yes or No) 
The primary endpoint for the study will be evaluated using the mRECIST Version 1.1 – GIST 
specific (hereafter referred to as “mRECIST”) based on independent radiologic review. 
Upon disease progression by mRECIST based on independent radiologic review, patients will 
discontinue their assigned treatment. 
NOTE: If the Investigator wishes to end treatment due to local progression based on mRECIST, 
without confirmation of progression by independent radiographic review, or before the 
independent read results are available, the Investigator must reach out to the Sponsor Medical 
Monitor to discuss. 
3.2. 
Number of Patients 
Approximately 426 patients (213 randomized to DCC-2618 and 213 randomized to sunitinib) 
will be randomized in this study at approximately 125 centers globally. 
3.3. 
Duration of Study 
Patients will be treated until they develop progressive disease as per mRECIST, experience 
unacceptable toxicity, or withdraw consent. At the time of progressive disease by mRECIST, 
based on independent radiologic review, patients will discontinue study drug. Patients will be 
eligible to receive study drug for up to 2 years. This will be extended by agreement between the 
Sponsor and Investigator for patients who exhibit evidence of clinical benefit and tolerability to 
the drug, and who adhere to the study procedures. The study will end following the last patient 
last visit.   

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4. 
STUDY POPULATION 
4.1. 
Inclusion Criteria 
Patients must meet all of the following criteria to be eligible to enroll in the study: 
1. Patients ≥ 18 years of age at the time of informed consent. 
2. Histologic diagnosis of GIST and must be able to provide an archival tumor tissue sample, 
otherwise, a fresh biopsy is required.  
3. Molecular pathology report with mutational status of KIT/PDGFRA must be available. 
Mutation status must be identified by using a tissue-based PCR/sequencing assay. Molecular 
pathology report with mutation status of KIT/PDGFRA must be provided to the Sponsor for 
review prior to randomization. If molecular pathology report is not available or insufficient, 
an archival tumor tissue sample or fresh biopsy is required for mutation status confirmation 
by the central laboratory prior to randomization. 
4. Patients must have progressed on imatinib or have documented intolerance to imatinib. 
Imatinib treatment must have been discontinued 10 days prior to the first dose of study drug.  
All prior imatinib treatment will count as one line of therapy (e.g. adjuvant imatinib and dose 
escalation of imatinib). 
5. Eastern Cooperative Oncology Group (ECOG) PS of ≤ 2 at screening. 
6. Female patients of childbearing potential must have a negative serum beta-human chorionic 
gonadotropin (β-hCG) pregnancy test at screening and negative pregnancy test at Cycle 1 
Day 1 prior to the first dose of study drug. 
7. Patients of reproductive potential must agree to follow the contraception requirements 
outlined in Section 6.11.9. 
8. Patients must have at least 1 measurable lesion according to mRECIST Version 1.1 
(non-nodal lesions must be ≥ 1.0 cm in the long axis or ≥ double the slice thickness in the 
long axis) within 21 days prior to the first dose of study drug. 
9. Adequate organ function and bone marrow reserve as indicated by the following central 
laboratory assessments performed at screening. 
• 
Absolute neutrophil count (ANC) ≥ 1000/µL 
• 
Hemoglobin ≥ 8 g/dL 
• 
Platelet count ≥ 75,000/µL 
• 
Total bilirubin ≤ 1.5 x the upper limit of normal (ULN) 
• 
Aspartate transaminase (AST) and alanine transaminase (ALT) ≤ 3 x ULN (≤ 5x ULN 
in the presence of hepatic metastases)  
• 
Creatinine clearance ≥ 50 mL/min based on Cockcroft Gault estimation  
• 
Prothrombin time (PT), international normalized ratio (INR), and partial thromboplastin 
time ≤ 1.5 x ULN. Patients on a stable regimen of anticoagulant therapy for at least one 
month prior to first dose of study drug may have PT/INR measurements > 1.5 x ULN 
if, in the opinion of the Investigator, the patient is suitable for the study. An adequate 
rationale must be provided to the Sponsor prior to randomization. 

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10. Resolution of all toxicities from prior therapy to ≤ Grade 1 (or patient baseline) within 
1 week prior to the first dose of study drug (excluding alopecia and ≤ Grade 3 clinically 
asymptomatic lipase, amylase, and creatine phosphokinase [CPK] laboratory abnormalities). 
11. The patient is capable of understanding and complying with the protocol and the patient has 
signed the informed consent document. Signed informed consent form (ICF) must be 
obtained before any study-specific procedures are performed and the patient must agree to 
not participate in any other interventional clinical trial while on treatment in this clinical trial. 
Participation in a noninterventional study (including observational studies) is permitted. 
4.2. 
Exclusion Criteria 
Patients meeting any of the following criteria will be excluded from the study:  
1. Treatment with any other line of therapy in addition to imatinib for advanced GIST. 
Imatinib-containing combination therapy in the first-line setting is not allowed. 
2. Patients with a prior or concurrent malignancy whose natural history or treatment have the 
potential to interfere with the safety or efficacy assessment of this clinical trial are not 
eligible. For example, patients receiving adjuvant cancer treatment are not eligible if those 
medications are potentially active against GIST or excluded per protocol. 
NOTE: Patients with a history of breast cancer, requiring continued hormonal treatment (e.g. 
anti-estrogen or an aromatase inhibitor) may continue treatment. Patients with a history of 
prostate cancer, requiring continued support with luteinizing hormone-releasing hormone 
(LHRH) agonists, with or without androgens, may continue treatment. 
NOTE: Patients may not be part of an ongoing or have prior participation in an 
investigational drug study within 30 days of screening. 
3. Patient has known active central nervous system metastases. 
4. New York Heart Association class II-IV heart disease, myocardial infarction within 6 months 
of cycle 1 day 1, active ischemia or any other uncontrolled cardiac condition such as angina 
pectoris, clinically significant cardiac arrhythmia requiring therapy, uncontrolled 
hypertension or congestive heart failure. 
5. Left ventricular ejection fraction (LVEF) < 50% at screening. 
6. Arterial thrombotic or embolic events such as cerebrovascular accident (including ischemic 
attacks) or hemoptysis within 6 months before the first dose of study drug. 
7. Venous thrombotic events (e.g. deep vein thrombosis) or pulmonary arterial events 
(e.g. pulmonary embolism) within 1 month before the first dose of study drug. Patients on 
stable anticoagulation therapy for at least one month are eligible. 
8. 12-lead ECG demonstrating QT interval corrected (QTc) by Fridericia's formula > 450 ms in 
males or > 470 ms in females at screening or history of long QT syndrome. 

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9. Use of strong or moderate inhibitors or inducers of cytochrome P450 (CYP) 3A4, including 
certain herbal medications (e.g. St. John’s Wort) within 14 days or 5 x the half-life 
(whichever is longer) prior to the first dose of study drug, and consumption of grapefruit or 
grapefruit juice within 14 days prior to the first dose of study drug. Please refer to the Indiana 
University Department of Medicine website (http://medicine.iupui.edu/clinpharm/ddis/main-
table/) for guidance on medications that inhibit/induce CYP3A4 enzymes.  See Section 
5.12.3.2. 
10. Use of known substrates or inhibitors of BCRP transporters within 14 days or 5 x the half-life 
(whichever is longer) prior to the first dose of study drug. Please refer to the US Food and 
Drug Administration’s (FDA) website for inhibitors and substrates 
(https://www.fda.gov/Drugs/DevelopmentApprovalProcess/DevelopmentResources/DrugInte
ractionsLabeling/ucm093664.htm).  See Section 5.12.3.2 
11. Major surgeries (e.g. abdominal laparotomy) within 4 weeks of the first dose of study drug. 
All major surgical wounds must be healed and free of infection or dehiscence before the first 
dose of study drug.  
12. Any other clinically significant comorbidities, such as uncontrolled pulmonary disease, 
active infection, or any other condition, which in the judgment of the Investigator, could 
compromise compliance with the protocol, interfere with interpretation of the study results, 
or predispose the patient to safety risks. 
13. Known human immunodeficiency virus or hepatitis C infection only if the patient is taking 
medications that are excluded per protocol (See Section 5.12.3.2), active hepatitis B, or 
active hepatitis C infection. 
14. If female, the patient is pregnant or lactating. 
15. Known allergy or hypersensitivity to any component of the study drug. Patients with a 
history of Stevens-Johnson syndrome on a prior tyrosine kinase inhibitor (TKI) are excluded. 
16. Gastrointestinal abnormalities including but not limited to: 
• 
inability to take oral medication 
• 
malabsorption syndromes  
• 
requirement for intravenous (IV) alimentation 
17. Any active bleeding excluding hemorrhoidal or gum bleeding. 

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On days of planned study visits, patients will be informed to take the study drug at the study site 
as per Table 1 (schedule of assessments).  The dose of study drug must be administered at the 
site after pre-dose assessments have been completed. The date, amount taken and time of study 
drug administration must be recorded in the patient’s source documents. 
If vomiting occurs immediately after taking a dose, that dose must not be “made up,” and the 
patient may be offered prophylactic anti-emetics prior to their next dose. 
For information on overdose, refer to Section 7.12 and the approved package insert or 
institutional guidelines for sunitinib. 
5.4. 
Study Drug Dose Interruption and Modification  
Sunitinib dose interruption and modification will follow guidelines as per the approved package 
insert or institutional guidelines. PK-guided sunitinib dosing is not allowed. Upon resumption 
following a dose interruption, the Investigator must continue with the patient’s original visit 
schedule calculated from Cycle 1 Day 1 (i.e. cycle day count is continuous and does not pause 
with a dose interruption). Clinic visits and assessments should continue during dose interruptions 
as per Table 1 (schedule of assessments). Dose interruptions of longer than 28 consecutive days 
will result in the patient being discontinued from the study.  If the patient is on 4 weeks on, 2 
weeks off cycle, the 28 days is inclusive of the 2 weeks off. 
DCC-2618 may be interrupted or modified (i.e. dose reduction) at the discretion of the 
Investigator at any time due to AE, to accommodate palliative treatment, or for other reasons 
after consultation with the Sponsor. An interruption must be limited to no more than 
28 consecutive days. Upon resumption following a dose interruption, the Investigator must 
continue with the patient’s original visit schedule calculated from Cycle 1 Day 1 (i.e. cycle day 
count is continuous and does not pause with a dose interruption). Clinic visits and assessments 
should continue during dose interruptions as per Table 1 (schedule of assessments). Dose 
interruptions of longer than 28 consecutive days will result in the patient being discontinued 
from the study. 
5.4.1. 
Study Drug Dose Interruption due to Planned Medical Procedures 
Sunitinib should be interrupted for major surgical procedures as per institutional guidelines or 
the approved package insert. 
For DCC-2618, surgeries that occur while the patient is on study, the extent of the procedure and 
rate of healing following the procedure must be taken into consideration. The following guidance 
applies: 
• Planned minimally invasive surgery: DCC-2618 must be interrupted for 3 days prior to and 3 
days after surgery.  
• Planned major surgery: DCC-2618 must be interrupted for 5 days prior to and 5 days after 
surgery. 
• Unplanned/emergent surgery: DCC-2618 must be interrupted immediately and restarted as 
described above for minimally invasive and/or major surgery. 
5.4.2. 
DCC-2618 Interruption and Modification Due to Toxicity 
DCC-2618 may be interrupted or reduced as described in Table 5 at the discretion of the 
Investigator at any time due to AEs and according to the guidelines described in Table 6, 
Table 7, Table 8, Table 9 and Table 10. Whenever possible, dose reductions should be 

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prospectively discussed with the Sponsor. If DCC-2618 is interrupted and then DCC-2618 is 
restarted, the patient should remain on their original cycle schedule.  
If any patient requires a dose lower than 50 mg QD or if a patient has had their dose reduced and 
has disease progression confirmed by the independent radiologic reviewer, the patient must be 
discontinued from study drug, the End-of-Treatment (EOT) Visit and Safety Follow up Visit 
must be conducted, and the patient must be followed for OS and PFS2. 
Table 5: 
Dose Reduction Steps for DCC-2618 
Starting Dose of DCC-2618  
1ST Dose Reduction 
2ND Dose Reduction 
150 mg QD 
100 mg QD 
50 mg QD 
 
If the AE returns to Grade 1 or baseline, the patient should be re-escalated. Efforts must be made 
to re-escalate the patient to the dose level at which the AE occurred. If the dose level is reduced 
to the 1st dose reduction level and the AE returns to Grade 1 or baseline, the patient may be re-
started at the starting dose level. If a patient has two sequential dose reductions and the AE 
returns to Grade 1 or baseline at the 2nd dose reduction level, the patient may be re-started at the 
1st dose reduction level and must remain at this dose level for 1 cycle without interruption before 
escalating to the starting dose level.   
If the AE leading to dose modification does not return to Grade 1 or baseline within 1 cycle (42 
days), then DCC-2618 must be discontinued, unless the event is considered not clinically 
significant by the Investigator, in which case the possibility of restarting the patient at a reduced 
dose level may be made after consultation with the Sponsor. 
Table 6: 
DCC-2618 Dose Modifications for Left Ventricular Systolic Dysfunction 
Toxicity Grade 
Management Guideline 
Any Grade 3 or 4 
Permanently discontinue DCC-2618  
 

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Table 7: 
DCC-2618 Dose Modifications and Management of Hypertension 
Toxicity Grade 
Management Guideline* 
Grade 1 
Prehypertension (systolic BP 120 - 139 
mm Hg or diastolic BP 80 - 89 mm Hg) 
Continue BP monitoring  
Continue DCC-2618 at the current dose level 
Grade 2  
Systolic BP 140 - 159 mm Hg or 
diastolic BP 90 - 99 mm Hg 
 Or 
Symptomatic increase by 
> 20 mm Hg (diastolic) or to 
> 140/90 mm Hg if previously within 
normal limits 
Treat BP to achieve diastolic BP ≤90 mmHg and or systolic BP ≤ 
140 mmHg 
• 
If BP was previously within normal limits, start 
antihypertensive monotherapy 
• 
If patient is already on antihypertensive medication, titrate 
dose up 
Continue the DCC-2618 at the current dose level 
Hold DCC-2618 if symptomatic increase by 20 mmHg (diastolic 
BP) until symptoms resolve and diastolic BP ≤90 mmHg 
On resuming DCC-2618, continue at the same dose level 
Grade 3  
Systolic BP ≥ 160 mm Hg or  
diastolic BP ≥ 100 mm Hg) 
Or  
More than 1 drug or more intensive 
therapy than previously indicated 
Treat to achieve diastolic BP ≤90 mmHg and or systolic BP 
≤ 140 mmHg 
• 
Start antihypertensive medication 
and/or 
• 
Increase current antihypertensive medication 
and/or 
• 
Add additional antihypertensive medication 
If symptomatic, hold DCC-2618 until diastolic BP ≤90 mmHg 
and/or systolic BP ≤140 mmHg, and symptoms resolve 
On resuming DCC-2618, continue at the same dose level 
If BP is not controlled with addition of a new or more intensive 
therapy, reduce DCC-2618 by 1 dose level 
If Grade 3 hypertension recurs despite DCC-2618 dose reduction 
and antihypertensive therapy, reduce the DCC-2618 by 1 additional 
dose level 
Grade 4 
Life-threatening consequences 
(e.g. malignant hypertension, transient 
or permanent neurologic deficit, 
hypertensive crisis) 
Treat BP per institutional guidelines 
Permanently discontinue DCC-2618 
BP=blood pressure 
*If BP remains controlled for at least 28 days, DCC-2618 dose re-escalation is permitted at the Investigator’s discretion. 

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Table 8: 
DCC-2618 Dose Modifications for Dermatologic Toxicities (except Alopecia) 
and Arthralgia/Myalgia 
Toxicity Grade1 
Dose Modification Guide 
Grade 1 
Institute support measures and continue DCC-2618 at the current dose 
Grade 2 
Institute support measures and continue DCC-2618 at the current dose 
If no improvement within 7 days, then interrupt DCC-2618 
• 
If the event returns to Grade 1 or baseline within 7 days, resume DCC-2618 at the 
same dose level 
• 
If the event returns to Grade 1 or baseline after 7 days, resume DCC-2618 at a 
reduced dose level 
If this is a recurrence, after event returns to Grade 1 or baseline, resume DCC-2618 at a 
reduced dose level regardless of time to improvement 
If after a dose reduction the event is maintained at Grade 1 or baseline for at least 1 cycle 
(42 days) of dosing, consider re-escalating DCC-2618 by 1 dose level 
Grade 3 
Institute support measures 
Interrupt DCC-2618 for at least 7 days or until the event returns to Grade 1 or baseline 
(maximum 28 days) 
• 
Resume DCC-2618 at a reduced dose level 
If after a dose reduction the event is maintained at Grade 1 or baseline for at least 1 cycle 
(42 days) of dosing, consider re-escalating DCC-2618 by 1 dose level 
Grade 4 
Discontinue DCC-2618 unless the event is not considered life-threatening. Patients may 
continue DCC-2618 with non-life threatening events upon discussion with the Sponsor. 
Grade: Any 
Stevens-Johnson Syndrome / Hypersensitivity Reaction: 
If a patient experiences Stevens-Johnson syndrome (SJS)/hypersensitivity reaction while 
being treated with DCC-2618, DCC-2618 must be permanently discontinued. The patient 
should be immediately referred to a hospital for clinical evaluation and supportive 
care/management per institutional guidelines. Re-administration of DCC-2618 is not 
allowed due to the risk of recurrent SJS/hypersensitivity reaction. Caution for recurrence 
of SJS with other similar agents (TKIs for GIST) is advised. 
1The severity of an AE that does not appear in the CTCAE v.5.0 scale must be assessed according to the 
criteria in Table 12. 
 

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Table 9: 
DCC-2618 Dose Modifications for Isolated Bilirubin Increased 
Toxicity Grade 
Management Guideline 
Grade 2 
Interrupt DCC-2618 until toxicity resolves to Grade 1 or baseline (maximum 28 days); 
resume DCC-2618 at 100 mg. 
Grade 3 or 4 
Interrupt DCC-2618 until toxicity resolves to Grade 1 or baseline (maximum 28 days); 
otherwise permanently discontinue DCC-2618. 
If the event returns to Grade 1 or baseline, resume DCC-2618 at 100 mg. 
If the reduced dose is tolerated without recurrence of the event for at least 28 days, 
consider re-escalating DCC-2618. 
If Grade 3 or higher toxicity recurs, discontinue DCC-2618 permanently. 
 
Table 10: 
DCC-2618 Dose Modifications for Treatment Related Adverse Events Not 
Mentioned Above 
Toxicity Grade 
Management Guideline1 
Any Grade 3 or 4 
Interrupt DCC-2618 dosing until event has resolved to Grade 1 or 
baseline 
Once the AE returns to Grade 1 or baseline, reduce DCC-2618 by 
1 dose level 
If a patient tolerates the reduced dose without recurrence of the event 
for at least 28 days, consider re-escalating the dose of DCC-2618 to 
the prior dose level 
Asymptomatic/Not clinically 
significant Grade 3 or 4 laboratory 
AEs (including CPK and lipase) that 
persist ≤10 days 
Closely monitor for clinical symptoms and continue DCC-2618 at 
the current dose level. Repeat labs within 10 days.  
Asymptomatic/Not clinically 
significant Grade 3 or 4 laboratory 
AEs (including CPK and lipase) that 
persist >10 days 
Closely monitor for clinical symptoms; for Grade 4 events, interrupt 
DCC-2618 until the event returns to Grade 3 
Asymptomatic Grade 3 or Grade 4 elevations of plasma enzyme: 
lipase or CPK do not require dose interruption 
Once the AE returns to Grade 3, resume DCC-2618 at the current 
dose level or consider reducing by 1 dose level per Investigator 
discretion after discussion with the Sponsor. 
Clinically Significant Grade 3 or 4 
laboratory AEs (including CPK and 
lipase) 
Interrupt the DCC-2618. If the Investigator assesses that restarting 
DCC-2618 is in the patient’s best interest, the Sponsor must be 
contacted for discussion and determination if restarting is allowed. 
AE=adverse event; CPK=creatine phosphokinase 
1 The rules for dose modifications for laboratory AEs will be based on local laboratory results. 
 

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5.5. 
Packaging and Labeling 
DCC-2618 will be supplied by the Sponsor as formulated drug in tablets for oral administration 
containing 50 mg of study drug in 30-count high-density polyethylene (HDPE) bottles with child 
resistant caps.  
Sutent® (sunitinib malate) 12.5 mg oral capsules will be supplied in its original form in 30 count 
HDPE bottles and relabeled by the Sponsor.  
Study drug labeling will be in accordance with applicable local and national regulations. Study 
drug will be provided and replaced via the Interactive Response Technology (IRT).  Study drug 
dispensation instructions will be provided in the Pharmacy Manual.  
5.6. 
Study Drug Storage Conditions 
DCC-2618 bottles must be stored tightly closed between 5°C-25°C (41°F-77°F). Keep away 
from areas of high humidity and sunlight (i.e. near showers in bathrooms) and according to the 
instructions provided in the Pharmacy Manual.  Excursions between 2°C-27°C (35.6°F-80.6°F) 
are allowed. 
Instructions regarding the storage and handling of DCC-2618 after dispensation to patients will 
be provided to site in the Pharmacy Manual. 
Refer to the provided package insert for information on sunitinib storage and handling. 
While at the clinical site, study drug must be stored in a secure, temperature-monitored area of 
limited access and only at the location(s) listed on the Form FDA 1572 or Investigator statement. 
5.7. 
Study Drug Compliance 
To ensure study drug compliance, the Investigator or designee must supervise all study drug 
dosing that occurs at the site. At each visit, site personnel must review that the patient is 
compliant with study drug dosing and remind the patient of study drug dosing requirements. 
Compliance must also be assessed by ongoing study drug count. 
If a patient demonstrates continued noncompliance of study drug dosing despite educational 
efforts, the Investigator must contact the Sponsor to discuss discontinuation of the patient from 
the study.  
5.8. 
Study Drug Accountability 
Accountability for the study drug at the study site is the responsibility of the Investigator. The 
Investigator must ensure that the study drug is used only in accordance with this protocol. Where 
allowed, the Investigator may choose to assign drug accountability responsibilities to a 
pharmacist or other appropriate individual. Drug accountability records indicating the study 
drug’s delivery date to the site, study drug inventory at the site, study drug dispensed to each 
patient, study drug returned by each patient, and study drug returned to the Sponsor or study drug 
destruction on site must be maintained by the clinical site. Accountability records must include 
dates, quantities, bottle numbers, and patient numbers. The study monitor must review drug 
accountability at the site on an ongoing basis during monitoring visits. If any dispensing errors or 
discrepancies are discovered, the Sponsor must be notified immediately. 

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Patients must be instructed to return all unused, partially used, and used study drug bottles to the 
site at each visit. The study monitor must verify study drug records and inventory throughout the 
study. 
5.9. 
Disposal, Return, or Retention of Unused Study Drug 
Patients must be instructed to return all used, partially used, and full study drug bottles. The site 
staff or pharmacy personnel (as appropriate) must retain all materials returned by the patients 
until returned to Sponsor or destroyed by the study site. If the study drug will be destroyed at the 
study site, the Investigator or designee, must ensure that the materials are destroyed in 
compliance with applicable environmental regulations, institutional policy, and any special 
instructions provided by the Sponsor. Destruction must be adequately documented. 
5.10. 
Method of Assigning Patients to Treatment 
Patients will be randomized in a 1:1 ratio to DCC-2618 150 mg or sunitinib 50 mg. Up to 10% of 
randomized patients may have KIT/PDGFRA WT GIST (wild-type KIT and wild-type PDGFRA 
regardless of the mutational status of any other gene). Randomization will be stratified by: 
• Mutational Status: KIT exon 9 mutation; KIT exon 11 mutation; KIT/PDGFRA WT; or other 
KIT (absence of exon 9 or 11)/PDGFRA mutations 
• Intolerance to imatinib (Yes or No) 
The IRT will be used to assign study drug treatment. Detailed instructions for randomization will 
be provided separately. 
5.11. 
Blinding and Unblinding 
This is an open-label study. 
5.12. 
Prior and Concomitant Treatment and Procedures 
5.12.1. 
Prior Medications and Procedures 
Information regarding any medication including vitamin supplements, over-the-counter 
medications, and oral herbal preparations or non-drug therapy taken, or procedure performed 
within 30 days prior to signing informed consent and before the first dose of study drug must be 
documented in the patient’s source documents and the electronic case report form (eCRF). 
5.12.2. 
Prior Anticancer Medications and Procedures 
Any prior anticancer medication or procedure must be documented in the patient’s source 
documents and the eCRF. 
5.12.3. 
Concomitant Medications 
All medications, including vitamin supplements, over-the-counter medications, and oral herbal 
preparations; non-drug therapies taken on or after the first dose of study drug through and 
including 30 days after the last dose of study drug must be documented in the patient’s source 
documents and the eCRF. In addition, any new treatments taken after the last dose of study drug 
through 30 days after the last dose must be documented in the patient's source documents and the 
eCRF. 

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5.12.3.1. 
Permitted Medication 
Patients may receive medications for symptomatic relief (e.g. analgesics, laxatives, antiemetics) 
as long as they are not prohibited by the protocol. 
For sunitinib, refer to the approved package insert or institutional guidelines. 
5.12.3.2. 
Prohibited Medications and Substances 
Prohibited medications and certain foods are not allowed from screening through the Safety 
Follow-up Visit. Except for study drug, anticancer therapies active or potentially active against 
GIST are prohibited during this study.  
Prior to randomization, all patients must follow the exclusions listed below: 
• Treatment with imatinib within 10 days prior to the first dose of study drug, or any other 
anticancer medication or line of therapy for advanced GIST. 
• Strong or moderate inhibitors or inducers of CYP3A4, including certain herbal medications 
(e.g. St. John’s Wort): discontinue at least 14 days (or 5x the half-life, whichever is longer) 
prior to the first dose of study drug.  
• Please refer to the Indiana University Department of Medicine website: 
(http://medicine.iupui.edu/clinpharm/ddis/main-table/) for guidance on medications that 
inhibit CYP3A4 enzymes. 
• Grapefruit or grapefruit juice:  must not be consumed at least 14 days prior to first dose of 
study drug 
• Known substrates or inhibitors of BCRP transporters:  discontinue at least 14 days or 5x the 
half-life (whichever is longer) prior to the first dose of study drug.  
• Please refer to the FDA’s website: 
(http://www.fda.gov/Drugs/DevelopmentApprovalProcess/DevelopmentResources/DrugInter
actionsLabeling/ucm093664.htm) for inhibitors and substrates for BCRP.  
After randomization and during the study, patients randomized to sunitinib will follow the 
approved package insert or institutional guidelines for prohibited medications.  
The following are prohibited after randomization and during the study for patients randomized to 
DCC-2618: 
• Strong and moderate inducers of CYP3A, including certain herbal medications 
(e.g. St. John’s Wort)  
Please refer to the Indiana University Department of Medicine website 
(http://medicine.iupui.edu/clinpharm/ddis/main-table/) for guidance on medications that  
induce CYP3A4 enzymes. 
5.12.3.3. 
Medications to Avoid if possible or Take with Caution 
After randomization and during the study for patients randomized to DCC-2618, the following 
medications should be avoided if possible or taken with caution following discussion with the 
Sponsor for patients receiving DCC-2618 (sites will be provided with updated information 
during the study): 
• Strong or moderate inhibitors of CYP3A including grapefruit juice 

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• Known substrates or inhibitors of BCRP transporters and P-glycoprotein 1 (permeability 
glycoprotein, also known as MDR1). Please refer to the FDA’s website for inhibitors 
http://www.fda.gov/Drugs/DevelopmentApprovalProcess/DevelopmentResources/DrugIntera
ctionsLabeling/ucm093664.htm 
• Medications dependent on CYP2C8 for their metabolism. Please refer to the Indiana 
University Department of Medicine website (http://medicine.iupui.edu/clinpharm/ddis/main-
table/) for guidance on these medicines.  
Patients taking any of the above listed medications must be closely monitored for any potential 
drug-drug interactions with DCC-2618. 
For sunitinib drug-drug interactions, refer to the approved package insert or institutional 
guidelines. 
5.12.4. 
Concomitant Procedures 
All procedures performed on or after the first dose of study drug through and including 30 days 
after the last dose of study drug must be documented in the patient’s source documents and the 
eCRF. 
Surgical resection or palliative radiotherapy during study treatment must be discussed with the 
Sponsor prior to implementation. Patients with PR are permitted resection of remaining tumor, 
but only after they have been on treatment for 12 months. If the Investigator believes it is in the 
best interest of the patient, surgical resection or palliative radiotherapy may be performed after 
discussion with the Sponsor. The patient will be censored in the PFS analysis from the time 
surgery or radiotherapy was performed. 
5.13. 
Other Precautions 
In order to mitigate the potential risk of photoirritation/phototoxicity, patients who are taking 
DCC-2618 must be instructed to avoid strong sunlight, sunlamps, and other sources of ultraviolet 
radiation for the duration of the study. Prophylactic skin care recommendations for all patients 
taking DCC-2618 include sunscreen with SPF ≥ 30, hypoallergenic moisturizing creams or 
ointments for dry skin, and gentle skincare with fragrance-free soaps and detergents. 
For sunitinib precautions, refer to the approved package insert or institutional guidelines. 

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6. 
STUDY ASSESSMENTS 
6.1. 
Screening 
Screening must occur within 28 days prior to the first dose of study drug to confirm that patients 
meet the selection criteria for the study. Radiologic imaging and dermatologic examination must 
be performed within 21 days prior to the first dose of study drug. The assessments to be 
conducted at screening are provided in Table 1 (schedule of assessments). 
6.2. 
Rescreening 
Patients may only be rescreened with the approval of the Sponsor. If a patient is rescreened, all 
screening assessments must be repeated except tumor tissue sample (as applicable). Imaging 
assessments, echocardiogram/MUGA, and dermatologic examinations do not need to be repeated 
if performed within 21 days of the first dose of study drug. Patients may only be rescreened 
once. If a patient is rescreened, the screening window will begin once the first rescreening 
assessment has been initiated.  
6.3. 
Treatment Period 
Patients will be randomized in the study after confirmation of all eligibility criteria. The first 
dose of study drug must be administered in the clinic on Cycle 1 Day 1. Study visits during the 
Treatment Period will occur as shown in Table 1 (schedule of assessments). Patients will be 
outpatients during the Treatment Period. All visits must occur within the windows specified. 
Patients who prematurely discontinue study drug must return for an EOT Visit within 7 days 
after the last dose of study drug. 
6.4. 
Follow Up 
Patients will be contacted by phone call for the Safety Follow-up Visit 30 days (+5 days) after 
the last dose of study drug to assess AEs; medications, including anticancer treatments; and 
procedures (see Section 6.11.11 for further details). Patients will be contacted by phone call for 
OS and PFS2 (see Section 6.10.2 for further details). 
6.5. 
Lost to Follow Up 
A patient will be considered lost to follow up if both of the following occur: 
• Patient misses 2 consecutive study visits and is subsequently unable to be contacted by phone 
call (3 documented attempts by phone within 2 weeks following the second missed visit). 
• Patient does not respond within 2 weeks to a registered letter sent after the 3 attempted phone 
contacts. 
6.6. 
Study Assessments 
The study specific assessments are detailed in this section and the schedule of assessments are 
outlined in Table 1. 
Additional unscheduled safety or efficacy assessments may be performed at any time as 
clinically indicated to determine the relevance of specific findings and/or the duration of events. 

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6.6.1. 
Timing of Assessment 
The EORTC QLQ-C30, EuroQol 5 Dimension 5 Level (EQ-5D-5L), DLQI, GP5 question from 
FACT-G, and the memory and concentration parts of the PRO-CTCAE questionnaires must be 
performed before the patient is evaluated by the Investigator or designee on the day of the 
scheduled visit. If the dermatologic examination or imaging assessments are completed within 7 
days of the scheduled visit and the patient is not evaluated by the Investigator or designee, the 
questionnaires do not need to be completed on that day. The GP5 question from FACT-G will be 
completed first followed by EORTC-QLQ-C30, DLQI, EQ-5D-5L and the memory and 
concentration parts of the PRO-CTCAE. 
All other assessments may be completed in any order as shown in Table 1 (schedule of 
assessments). 
6.7. 
Informed Consent Procedure 
Each patient must sign and date a study-specific ICF before any study specific procedures can be 
performed. The ICF will comply with all applicable regulations governing the protection of 
patients. An ICF, approved by the Sponsor and the site's Institutional Review Board 
(IRB)/Independent Ethics Committee (IEC)/Research Ethics Board (REB) must be used. The 
Investigator or designee must document the consenting process, including the date when the ICF 
was signed in the patient’s source document. 
6.8. 
Assigning Patient Number 
A unique patient identification number (patient number) will be assigned to each patient once 
informed consent is obtained. Detailed instructions on assigning patient numbers will be 
provided in the Study Reference Manual. If a patient is rescreened, the patient retains the original 
patient number. 
6.9. 
Demographics and Medical History 
Demographic information must be collected at screening. 
Cancer history and prior treatment (including reason for discontinuation) must be obtained 
during screening. Cancer history will include: 
• Known histologic diagnosis of GIST 
• Tumor mutational status 
• All prior cancer treatment regimens, including: 
o Surgery (including tumor tissue sample[s]): include date(s), site(s), and extent of 
resection (e.g. tumor tissue sample only, R0, R1, or R2) 
o Prior imatinib therapy: include dates of treatment, including dose and dosing regimen, 
reason for treatment (e.g. adjuvant therapy or for metastatic disease), best response, date 
of disease progression or date and reason for treatment discontinuation other than disease 
progression. 
o Radiation therapy: include the site(s) treated, total dose(s), date(s) of treatment, and 
response(s) 

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o Other procedures, such as radiofrequency ablation (if applicable) 
Molecular pathology report with mutational status of KIT/PDGFRA must be provided to the 
Sponsor for review prior to randomization.  If molecular pathology report is not available or 
insufficient, an archival tumor tissue sample or fresh biopsy is required for mutation status 
confirmation prior to randomization. Specific instructions will be provided in the Study 
Reference Manual. 
Medical history, including any significant conditions or diseases that stopped at or prior to 
informed consent, must be elicited from each patient during screening. Based on the medical 
history, the patient must be assessed for any disqualifying medical conditions as specified in the 
inclusion and exclusion criteria. The medical history shall include a complete review of systems, 
past medical and surgical histories, and any allergies. Ongoing conditions are considered 
concurrent medical conditions; if possible, the start date for these comorbidities must be 
documented. 
6.10. 
Efficacy 
6.10.1. 
Radiologic Imaging 
All patients will have radiographic tumor evaluation by CT scans of the pelvis, abdomen, and 
chest according to Table 1 (schedule of assessments). Radiologic imaging performed as standard 
of care prior to informed consent may be used as the screening assessment as long as the imaging 
was performed within 21 days prior to the first dose of study drug. Radiologic imaging may be 
performed up to 7 days prior to the corresponding study visit or post dose at the study visit.  
Following Cycle 7 Day 1, an initial indication of a PR or CR based on investigator assessment 
must be confirmed ≥ 4 weeks following initial response. Magnetic resonance imaging (MRI) 
scans of the abdomen/pelvis and CT scan without contrast of the chest may be used for patients 
who are allergic to radiographic contrast media or per Investigator's discretion based on the best 
interest of the patient after discussion with the Sponsor. Additionally, for patients whose local 
regulatory authority and/or ethics committee has not approved use of CT scans, MRIs may be 
used. Throughout the study, the same assessment technique used on a patient at screening must 
continue to be used for that patient for the duration of their study participation unless there is a 
safety risk as determined by the Investigator. Ultrasound scanning is not an acceptable substitute 
for CT scanning. 
Copies of all imaging scans must be obtained and sent to an independent imaging vendor 
designated by the Sponsor as outlined in a separate protocol specific manual. The independent 
imaging vendor will assess the quality of the images and be responsible for performing an 
independent radiologic review. 
The independent imaging vendor must ensure that the independent radiologic reviewer remains 
blinded to the local assessment from the Investigator. This and all other imaging procedures will 
be documented in a protocol specific review charter agreed upon between the Sponsor and the 
independent imaging vendor before initiation of any independent radiologic reviews. 
The independent radiologic reviewer and Investigator will assess tumor response using 
mRECIST (see Section 9.2.1.1). Response as determined by the Investigator will be recorded in 
the eCRF. Data from the independent radiologic review (IRR) will be used for the primary 
endpoint analysis. The IRR will also assess tumor response using Choi criteria, and this will be 
used for a secondary endpoint. More details on image acquisition guidelines and radiographic 
assessment will be provided in a separate protocol specific manual. 

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language, the patient will be exempt from taking the questionnaire. Patient-entered data will not 
be modified by the Investigator or site staff, ePRO vendor, CRO or Sponsor. 
6.10.3.2. 
Dermatology Life Quality Index 
The Dermatology Life Quality Index (DLQI) is a validated questionnaire used to measure the 
impact of skin symptoms on the QOL of an affected person (32). There are 10 questions, 
covering the following topics: symptoms, embarrassment, shopping and home care, clothes, 
social and leisure, sport, work or study, close relationships, sex, and wider treatment 
consequences. Each question refers to the impact of the skin disease on the patient’s life over the 
previous week. Each question is scored at four levels from "Not at all" (0), through "A little", 
and "A lot", to "very much"(3), giving a possible summary score range from 0 (meaning no 
impact of skin disease on QOL to 30 (meaning maximum impact on QOL. A difference of four is 
considered to be clinically significant in inflammatory skin disease.  Validated translations will 
be provided for sites in non-English speaking countries. 
Patients will be asked to complete DLQI in their native language using an ePRO system before 
dosing at the visits indicated in Table 1 (schedule of assessments). If the DLQI is not available in 
the patient’s native language, the patient will be exempt from taking the questionnaire. Patient-
entered data will not be modified by the Investigator or site staff, ePRO vendor, CRO or 
Sponsor. 
6.10.3.3. 
GP5 Question from FACT-G 
The GP5 burden-of-side-effects question, a part of the Functional Assessment of Chronic Illness 
Therapy (FACIT) Functional Assessment of Cancer Therapy - General (FACT G) questionnaire, 
is a validated, standardized, patient completed question used extensively in international clinical 
studies (33). It was developed to assess health related QOL in patients with cancer. The time 
required for completion is approximately 20 seconds. The question is completed by the patient’s 
selection of one of the following options of “not at all,” “a little bit,” “somewhat,” “quite a bit,” 
and “very much”. Validated translations will be provided for sites in non-English speaking 
countries. 
Patients will be asked to complete the GP5 question from FACT G in their native language using 
an ePRO system before dosing at the visits indicated in Table 1 (schedule of assessments). If the 
GP5 question from FACT-G is not available in the patient’s native language, the patient will be 
exempt from taking the questionnaire. Patient-entered data will not be modified by the 
Investigator or site staff, ePRO vendor, CRO or Sponsor. 
6.10.3.4. 
Memory and Concentration Portions of PRO-CTCAE Library 
The NCI-PRO-CTCAE measurement system was developed to gather symptomatic AEs by 
patient self-reporting (34). The NCI-PRO-CTCAE library is comprised of 124 items representing 
78 symptomatic AEs. The NCI-PRO-CTCAE items evaluate symptom attributes such as 
symptom occurrence, frequency, severity, and interference with daily activities, and are intended 
to be complementary to the items in the NCI’s CTCAE. Validated translations will be provided 
as available for specific non-English speaking countries. If validated translations are not 
available for the patient, the patient will be exempt from completing this questionnaire.  
Patients will be asked to complete questions 46 and 47 of the PRO-CTCAE in their native 
language, if available, using an ePRO system before dosing at the visits indicated in Table 1 
(schedule of assessments). The time to fill out all the questions is less than a minute. Patient-

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entered data will not be modified by the Investigator or site staff, ePRO vendor, CRO or 
Sponsor. 
Patients are asked to rate the severity of problems with concentration/memory on a five level 
Likert scale going from None to Very severe. They are also asked to rate how much those 
problems interfered with their usual activities on a five-level Likert Scale going from Not at all 
to Very much. 
6.10.3.5. 
EuroQol 5-Dimension 5-Level (EQ-5D-5L) 
The EQ-5D-5L is a validated, standardized, patient-completed questionnaire developed by the 
EuroQol group and used commonly in clinical studies to provide a measure of patient utility for 
clinical and economic appraisals (26). The time required for completion is approximately 2 
minutes. Validated translations of the EQ-5D-5L will be provided for sites in non-English-
speaking countries.  
The first 5 items of the EQ-5D-5L measure the health dimensions of mobility, ability to conduct 
self-care, ability to conduct usual activities, pain/discomfort, and anxiety/depression. The patient 
will select from 5 response levels (no problems, slight problems, moderate problems, severe 
problems, extreme problems) to rate their level of difficulty on that dimension that day. 
The sixth item is a EuroQol visual analogue scale (EQ-VAS). The EQ-VAS records the patient’s 
self-rated health on a vertical scale with endpoints labeled “the best health you can imagine” and 
“the worst health you can imagine.” This information can be used as a quantitative measure of 
health as judged by the individual patient. A patient is asked to “mark an X on the scale to 
indicate how your health is TODAY” and “write the number you marked on the scale in the box 
below.” 
Patients will be asked to complete EQ-5D-5L in their native language using an ePRO system 
before dosing at the visits indicated in Table 1 (schedule of assessments). If the EQ-5D-5L is not 
available in the patient’s native language, the patient will be exempt from taking the 
questionnaire. Patient-entered data will not be modified by the Investigator or site staff, ePRO 
vendor, CRO or Sponsor. 
6.11. 
Safety 
The safety profile will be assessed based on physical examinations, ECOG PS, changes from 
baseline in vital signs, ECGs, LVEF based on echocardiogram/multigated acquisition scan 
(MUGA), dermatologic examination, and clinical laboratory tests, and the reporting of AEs. 
6.11.1. 
Physical Examinations 
A full physical examination will be performed at screening. A full physical examination includes 
a review of the following systems: head/neck/thyroid, eyes/ears/nose/throat, respiratory, 
cardiovascular, lymph nodes, abdomen, skin, musculoskeletal, and neurological. Breast, 
anorectal, and genital examinations will be performed when medically indicated. At all other 
visits, examinations will be driven by clinical findings and/or patient complaints. After 
screening, any clinically significant abnormal findings in physical examinations must be reported 
as AEs. 

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6.11.2. 
Eastern Cooperative Oncology Group Performance Status 
ECOG PS (27) will be assessed according to the schedule of assessments in Table 1 (schedule of 
assessments).  ECOG PS may be performed pre or post dose. 
6.11.3. 
Vital Signs, and Weight and Height 
Vital sign measurements, height, and weight will be performed according to Table 1 (schedule of 
assessments). Vital sign measurements will include sitting blood pressure, pulse, respiratory rate, 
and body temperature. These will be assessed following a 5-minute rest (seated or supine 
position). 
6.11.4. 
Electrocardiograms 
Digital, 12-lead ECGs will be performed with central over-reading according to the schedule of 
assessments in Table 1 (schedule of assessments). All sites will be provided with an ECG 
machine and associated materials by the central ECG diagnostic service. 
Performance of all ECGs must adhere to the following guidelines: 
• All standard digital ECGs must be performed after the patient has been in the supine or semi-
recumbent position for at least 15 minutes. The 15-minute rest period will start after the 
placement of the ECG leads. 
• The ECG must be performed before the dose of study drug. 
A hard copy of the ECG must be printed and signed by the Investigator at the site.  
ECG data will be transmitted to the central ECG diagnostic service and all interval 
measurements will be reviewed and adjusted using the central ECG core labs methodology by a 
trained ECG analyst. A cardiologist at the central ECG diagnostic service will then review each 
ECG to confirm if intervals were calculated correctly and to provide an interpretation. A report 
containing this information will be provided to the site for review and signature by the 
Investigator. This report will be filed with the machine ECG report for each visit in the patient’s 
source documents. The values reported by the central ECG diagnostic service will be used for 
data analysis. 
Heart rate and the following ECG intervals will be captured in the database: 
• PR interval 
• QT, QT interval corrected using Bazett’s formula (QTcB) (QTcB = QT/RR0.50) and QT 
interval corrected by Fridericia’s formula (QTcF) (QTcF = QT/RR1/3) intervals 
• QRS duration 
• RR interval 
The central ECG diagnostic service's standard reference ranges will be used throughout the 
study. 

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6.11.5. 
Echocardiograms/Multigated Acquisition Scans 
Echocardiograms or multigated acquisition scans (MUGAs) will be performed according to 
Table 1 (schedule of assessments).  Echocardiogram or MUGA performed as standard of care 
prior to informed consent may be used as the screening assessment as long as the 
echocardiogram or MUGA was performed within 28 days prior to the first dose of study drug. 
The same modality (echocardiogram or MUGA) must be used throughout the study. LVEF must 
be documented in the patient’s source documents and eCRF. 
6.11.6. 
Dermatologic Examination 
All patients will be assessed by a consulting dermatologist for skin lesions, especially for SCC, 
actinic keratosis, and keratoacanthomas, according to Table 1 (schedule of assessments) and as 
clinically indicated. The examinations must include the entire skin. Any dermatologic exam that 
meets the protocol criteria that was performed as standard of care prior to informed consent may 
be used as the screening assessment as long as the exam was performed within 21 days prior to 
the first dose of study drug. Any new or changing skin lesions noted during the course of 
treatment must be documented in the patient’s source documents and eCRF. In case of suspected 
SCC or keratoacanthomas, a skin biopsy must be taken for confirmation of diagnosis by a 
certified pathologist at the clinical site. Samples with confirmed SCC or keratoacanthoma lesions 
will be sent to a central laboratory for histopathological and/or molecular analysis. Comparative 
analysis of all patient lesions will be performed to investigate signifying aberrant oncogene 
pathway(s) and their potential relationship to the study drug. For more information on the 
management of SCC, actinic keratosis, and keratoacanthomas, considered to be AESIs, see 
Section 7.9. 
6.11.7. 
Clinical Laboratory Tests 
Blood and urine samples will be collected according to Table 1 (schedule of assessments) and 
analyzed at a central laboratory. All blood samples must be collected while patients are in a 
seated or supine position. Specific instructions for the collection, processing and shipment of 
samples will be provided in a separate laboratory manual. Laboratory test results that are 
abnormal and considered clinically significant must be reported as AEs (Section 7.7.1). 
Screening laboratory results from the central laboratory must be available before randomization. 
All samples must be collected in accordance with acceptable laboratory procedures and graded 
for toxicity as defined by the National Cancer Institute Common Terminology Criteria for 
Adverse Events (NCI-CTCAE), Version 5.0. 
Available local laboratory test results will be used for treatment management decisions (dose 
interruptions or dose modifications [Section 5.4.2]) and initial assignment of CTCAE grading. 
Central laboratory results will be used for final assignment of CTCAE grading. In the case of 
different grades associated with local versus central laboratory results for AEs, the Investigator 
should determine which laboratory values will be used for documenting grading of AEs. The 
local versus central laboratory result with the highest grade should be considered to document 
grading of AEs. 
The safety laboratory tests are provided in Table 11. 

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Table 11: 
Safety Laboratory Tests 
Serum Chemistry 
Hematology 
Urinalysis2 
Glucose 
Blood urea nitrogen 
Creatinine 
Sodium 
Potassium 
Calcium 
Magnesium 
Phosphorus  
Total and direct bilirubin 
Alkaline phosphatase 
Aspartate aminotransferase  
Alanine aminotransferase 
Lactate dehydrogenase 
Total protein 
Albumin 
Creatine Phosphokinase 
Globulin 
Triglycerides 
Lipase 
Hemoglobin 
• Mean corpuscular hemoglobin 
• Mean corpuscular hemoglobin 
concentration 
• Mean corpuscular volume 
Hematocrit 
Platelets 
Leukocytes 
Reticulocytes 
Differential (absolute): 
• Eosinophils 
• Basophils 
• Neutrophils 
• Lymphocytes  
• Monocytes 
Coagulation Studies1 
Activated partial thromboplastin time  
Prothrombin time 
International Normalized Ratio 
Urine protein  
Urine blood 
Specific gravity  
Urine ketones  
Urine glucose  
Thyroid Testing 
Thyroid stimulating hormone (TSH) 
Total triiodothyronine (T3) 
Total thyroxine (T4) 
1. For patients taking anticoagulants, testing will be performed according to Table 1 (schedule of assessments). 
Monitoring of coagulation tests must be increased for as long as deemed clinically appropriate following a 
change in anticoagulant dose during the study. 
2. If any result is abnormal, a microscopic analysis must be performed by the central laboratory. 
6.11.8. 
Pregnancy Test 
A serum β-hCG test to rule out pregnancy in women of childbearing potential will be obtained at 
screening and analyzed at the central laboratory. A urine pregnancy test will be completed at all 
other visits as outlined in Table 1 (schedule of assessments). A local serum pregnancy test may 
be performed instead of urine if it is the standard practice for the site and the results are received 
prior to the patient being dosed in the clinic. Pregnancy testing will not be required for patients 
who are non-childbearing females, defined as one who is post-menopausal (amenorrhoeic for 
≥ 12 months with a follicle stimulating hormone (FSH) ≥ 40 mIU/mL) or has documented 
complete oophorectomy or hysterectomy. 
6.11.9. 
Contraception and Pregnancy Avoidance Measures 
6.11.9.1. 
Contraception 
The effects of DCC-2618 on sperm, conception, pregnancy, and lactation are not known. 
Participation in this study requires patients receiving DCC-2618 to agree to use 2 methods of 
contraception with one of the methods being highly effective. Methods of contraception must be 
in successful use from at least 14 days prior to the first dose of DCC-2618 and until 104 days 
following the last dose of DCC-2618. 

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Participation in this study requires patients receiving sunitinib to agree to use effective methods 
of contraception as per the approved package insert or institutional guidelines. 
Contraception for the patient is waived for the following: 
• True abstinence for the patient, when this is in line with the preferred and usual lifestyle of 
the patient. Periodic abstinence (e.g. calendar, ovulation, symptothermal, and postovulation 
methods) and withdrawal are not acceptable methods of contraception. 
• If the male has documented bilateral orchiectomy or is considered infertile as documented 
through examination of a semen specimen or by demonstration of the absence of the vas 
deferens by ultrasound before the first dose of the study drug. 
• If the female is of non-childbearing potential, per the following: 
o Postmenopausal: spontaneous amenorrhea for at least 12 consecutive months and have a 
serum FSH level ≥ 40 mIU/mL 
o Documented hysterectomy or a bilateral oophorectomy/salpingo-oophorectomy 
NOTE: All other female patients (including patients with tubal ligations and patients who do not 
have a documented hysterectomy) will be considered to be of childbearing potential. 
Acceptable highly effective methods of contraception: 
• Vasectomy 6 months or more previously, with a negative post-vasectomy semen analysis for 
sperm. 
• Bilateral tubal ligation performed at least 6 months previously. 
• Continuous use of an intrauterine device for at least 90 days previously 
• Combined (estrogen and progestin containing) or progestin-only hormonal contraception 
associated with inhibition of ovulation: 
o oral 
o intravaginal 
o transdermal 
o injectable 
o implantable 
NOTE: Hormonal contraceptives can be used as highly effective method of contraception unless 
they are one of the prohibited medications as described in Section 5.12.3.2 as the efficacy of the 
hormonal contraceptives may be affected due to potential drug-drug interactions with the study 
drug. 
Acceptable methods of contraception: 
• Male and female condom with or without spermicide 
• Barrier contraception (such as diaphragm, cervical cap or sponge) and spermicide 

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o In countries where spermicide is not available, barrier contraception without spermicide 
is acceptable 
Additional notes: 
Acceptable methods of contraception listed above are examples. Local requirements may 
prohibit the use of some of these examples. Please contact the Sponsor with any questions. 
• Female condom cannot be used with male condom (as a double method of contraception) due 
to risk of tearing. 
• Male and female patients who are not sexually active at the time of screening must agree to 
follow the contraceptive requirements of this study if they become sexually active with a 
partner of the opposite sex. 
• If applicable, additional contraception requirements may need to be followed according to 
local regulations and/or requirements. 
• Male patients who are receiving DCC-2618 must not donate sperm after the first dose of 
study drug, throughout the study, and for 104 days following the last dose of DCC-2618. 
They should seek advice on conservation of sperm prior to the first dose of DCC-2618. 
• Female patients and female partners of male patients who are receiving DCC-2618 must not 
plan to become pregnant during the study through 104 days following the last dose of DCC-
2618. 
• Female patients who are receiving sunitinib must not plan to become pregnant during the 
study through the last dose of sunitinib. Female partners of male patients receiving sunitinib 
must not plan to become pregnant during the study through the last dose of sunitinib. 
• Male patients whose female partner becomes pregnant through well-documented in vitro 
fertilization (donated sperm) or banked sperm (collected before the patient received study 
drug), must be compliant with the contraception requirements. In this scenario, the male 
patient must commit to using acceptable methods of contraception (to ensure there is no 
exposure of the fetus) for the duration of the study and until 104 days after the last dose of 
DCC-2618 or until the last dose of sunitinib.  
Unique situations that may not fall within the above specifications must be discussed with the 
Sponsor. 
If there is any question that a woman of childbearing potential or male patient will not reliably 
comply with the requirements for contraception, that patient must not be entered into the study. 
6.11.9.2. 
Pregnancy 
Patients receiving DCC- 2618 must be counseled to inform the Investigator of any pregnancy 
that occurs during study treatment and for 104 days after the last dose of DCC-2618.  Patients 
receiving sunitinib must be counseled to inform the Investigator of any pregnancy that occurs 
during study treatment. An exception is made for pregnancies that occur 104 days after the last 
dose of DCC-2618 or after the last dose of sunitinib resulting from donated sperm or sperm 
banked before study drug exposure. 
If a female patient becomes pregnant while participating in the study, study drug must be 
permanently discontinued immediately. If the female partner of a male patient becomes pregnant 

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while participating in the study, the patient must notify the Investigator immediately. The male 
patient must commit to use acceptable methods of contraception (to ensure there is no exposure 
of the fetus to study drug) for the duration of the study and until 104 days after the last dose of 
DCC-2618 or after the last dose of sunitinib. The Investigator must notify the Sponsor or 
designee within 1 business day of the site's knowledge of the patient’s (or partner's) pregnancy.  
Instructions will be provided in the Study Reference Manual. 
If the patient was receiving DCC-2618, the patient or female partner of the male patient must be 
followed until the end of the pregnancy and the infant must be followed for 1 year after the birth, 
provided informed consent is obtained. A separate ICF must be provided to explain these 
follow-up activities. Pregnancy itself does not constitute an AE. 
6.11.10. 
Adverse Events 
All AEs will be assessed, documented, and reported in accordance with International Conference 
on Harmonisation (ICH) Good Clinical Practice (GCP) guidelines. Section 7 outlines the 
definitions, collection periods, criteria and procedures for documenting, grading, and reporting 
AEs. A separate document that details AE eCRF completion guidelines for the Investigator, as 
well as training, will be provided. 
6.11.11. 
Safety Follow Up 
All patients must be followed for AEs; medications, including any anticancer treatments; and 
procedures until 30 days (+5 days) following the last dose of study drug. 
6.12. 
Pharmacokinetics 
6.12.1. 
Sample Collection 
At the visits indicated in Table 1 (schedule of assessments), blood samples will be collected from 
patients receiving DCC-2618 for the determination of the concentrations of DCC-2618 and its 
metabolite, DP-5439. Pre-dose blood samples must be collected within 60 minutes before dosing 
and post dose blood samples must be collected ±30 minutes of the nominal time point. An 
unscheduled PK sample may be taken at the time of the onset of a new suspected, treatment-
related AE when requested by the Sponsor. 
Samples from the PK sampling will be kept frozen by the Sponsor or its designee until all 
analyses have been completed and then disposed of according to the Sponsor or designee 
standard operating procedures. 
For each visit with a PK blood draw, a record of study drug administration must be collected as 
described in Section 5.3. The collection date and time that each PK blood sample is drawn must 
also be recorded. 
Details on sample collection, processing, and shipping will be provided in a separate 
protocol-specific Laboratory Manual. 
6.12.2. 
Sample Assessment 
The PK data from this study will be analyzed by population PK methods to generate PK 
parameters, which may be pooled with PK data from other DCC-2618 studies and may be 
reported separately from the primary results of this study. The population PK model will assess 
the effect of various covariates (e.g., age, sex, race, body weight, renal and hepatic function) on 

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6.15. 
Healthcare Utilization 
6.15.1. 
Healthcare Utilization Questionnaire (HCUQ) 
The Healthcare Utilization Questionnaire (HCUQ) [See Appendix 17.2] was designed 
specifically to collect data on the use of healthcare resources. It will be completed via a patient 
interview conducted by the Investigator or designee participating in this study at the visits 
indicated in Table 1 (schedule of assessments). The required time for completion is 
approximately 3-5 minutes.  
The first section of the questionnaire deals with utilization of ambulatory healthcare services, 
with the staff member asking the patient about utilization of each of the services (emergency 
room, ambulance, primary care physician, specialist physician, counseling, other) and recording 
information as to whether the type of service had been used in the past 28 days (yes, no) and, if 
so, the number of times it was utilized. The second section proceeds in a similar way with data 
collection regarding the number of hospital admissions in the past 28 days, the length of stay, 
and the reason for each admission (disease/treatment related, other). The last section focuses on 
paid care provided in the patient’s home by a nurse, home health aide, hospice worker, or 
another provider type in the last 28 days, with collection of whether service was provided and, if 
so, the number of days and the number of hours per day. 

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7. 
ADVERSE EVENT AND SERIOUS ADVERSE EVENT 
DOCUMENTATION, SEVERITY GRADING, AND REPORTING 
7.1. 
Adverse Events 
An AE is defined as any untoward medical occurrence in a patient administered a pharmaceutical 
product during the study, which does not necessarily have a causal relationship with the study 
drug. An AE can be any unfavorable and unintended sign (e.g. including an abnormal laboratory 
finding), symptom, or disease temporally associated with the use of the study drug, whether or 
not it is considered to be study drug related. This includes any newly occurring event or previous 
condition that has increased in severity or frequency after the ICF is signed. 
Planned hospital admissions or surgical procedures for an illness or disease that existed before 
the patient was screened in the study and progression of underlying disease are not to be 
considered AEs unless the condition deteriorated in an unexpected manner during the study (e.g. 
surgery was performed earlier than planned). 
Diagnostic and therapeutic non-invasive and invasive procedures, such as surgery, must not be 
reported as AEs. However, the medical condition for which the procedure was performed must 
be reported if it meets the definition of an AE. 
Elective surgeries or procedures must not be reported as AEs but must be documented on the 
appropriate eCRF page. 
Each AE must be assessed immediately to determine if it meets the definition of serious 
(Section 7.8). If an SAE occurs, expedited reporting must follow local and international 
regulations, as appropriate. 
7.2. 
Severity Assessment 
The Investigator must determine and record the severity of all serious and non-serious AEs. The 
NCI-CTCAE, Version 5.0, must be used for grading the severity of AEs (Cancer Therapy 
Evaluation Program website; available at: https://evs.nci.nih.gov/ftp1/CTCAE/CTCAE_5.0/.  
The severity of an AE that does not appear in the CTCAE scale must be determined according to 
Table 12. 
Table 12: 
Severity Grading Scale 
Grade 1 (Mild) 
Asymptomatic or mild symptoms; clinical or diagnostic observations only; 
intervention not indicated.   
Grade 2 (Moderate) 
Minimal, local or noninvasive intervention indicated; limiting age-appropriate 
instrumental Activities of Daily Living. 
Grade 3 (Severe) 
Severe or medically significant but not immediately life-threatening; 
hospitalization or prolongation of hospitalization indicated; disabling; 
limiting self-care Activities of Daily Living. 
Grade 4 (Life-threatening) 
Life-threatening consequences; urgent intervention indicated. 
Grade 5 (Death) 
Death related to AE. 
 

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7.3. 
Causality Assessment 
The Investigator’s assessment of relationship of the AE, if any to the study drug must be 
provided for all AEs. An Investigator’s causality assessment is the determination of whether 
there is reasonable possibility that the study drug caused or contributed to an AE. 
Relationship to study drug administration must be determined by the Investigator according to 
the following criteria in  Table 13. 
Table 13: 
Relationship to Study Drug Criteria 
Related 
There is an association between the event and the administration of study drug, a 
plausible mechanism for the event to be related to the study drug and causes other 
than the study drug has been ruled out, and/or the event re-appeared on re-exposure 
to the study drug. 
Possibly Related 
There is an association between the event and the administration of the study drug 
and there is a plausible mechanism for the event to be related to study drug, but 
there may also be alternative etiology, such as characteristics of the patient's clinical 
status or underlying disease. 
Unlikely Related 
The event is unlikely to be related to the study drug and likely to be related to 
factors other than the study drug. 
Not Related 
The event is related to an etiology other than the study drug (the alternative etiology 
must be documented in the study patient’s medical record). 
 
For the purpose of the safety analyses, all AEs that are classified as possibly related will be 
considered treatment-related events. 
7.4. 
Study Drug Action Taken 
The Investigator must classify the study drug action taken with regard to the AE. The action 
taken must be classified according to the categories shown in Table 14. 
Table 14: 
Classification for Study Drug Action Taken with Regard to an Adverse 
Event 
Classification 
Definition 
Dose Not Changed 
Study drug dose not changed in response to an AE. 
Dose Reduced 
Study drug dose reduced in response to an AE. 
Drug Interrupted 
Study drug administration interrupted in response to an AE. 
Drug Withdrawn 
Study drug administration permanently discontinued in response to an AE. 
Not Applicable 
Action taken regarding study drug administration does not apply. 
"Not applicable" must be used in circumstances such as when the study drug had 
been completed before the AE began and no opportunity to decide whether to 
continue, interrupt, or withdraw study drug is possible. 
 
7.5. 
Adverse Event Outcome 
An AE must be followed until the Investigator has determined and provided the final outcome. 
The outcome must be classified according to the categories shown in Table 15. 

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Table 15: 
Classifications for Outcome of an Adverse Event 
Classification 
Definition 
Recovered/Resolved 
Resolution of an AE with no residual signs or symptoms. 
Recovered/Resolved with Sequelae 
Resolution of an AE with residual signs or symptoms. 
Recovering/Resolving 
Improvement of an AE 
Not Recovered/Not Resolved (Continuing) 
Either incomplete improvement or no improvement of an AE, 
such that it remains ongoing. 
Fatal 
Outcome of an AE is death. "Fatal" must be used when death is 
at least possibly related to the AE. 
Unknown 
Outcome of an AE is not known (e.g., a patient lost to 
follow-up). 
 
7.6. 
Treatment Given 
The Investigator must ensure adequate medical care is provided to patients for any AEs. In 
addition, the Investigator must describe whether any treatment was given for the AE. "Yes" is 
used if any treatment was given in response to an AE and may include treatments such as other 
medications, hospitalization, surgery, or physical therapy. "No" indicates the absence of any kind 
of treatment for an AE. 
7.7. 
Additional Points to Consider for Adverse Events 
7.7.1. 
Clinically Significant Assessments 
Study assessments including laboratory tests, ECGs, physical examinations, and vital signs must 
be assessed and those deemed as clinically significant must be documented as an AE. When 
possible, a clinical diagnosis for the study assessment must be provided rather than the abnormal 
test result alone (e.g. urinary tract infection, anemia). In the absence of a diagnosis, the abnormal 
study assessment itself may be listed as the AE (e.g. bacteria in urine or decreased hemoglobin). 
An abnormal study assessment is considered clinically significant if the patient has 1 or more of 
the following: 
• Worsening, from baseline, concomitant signs or symptoms related to the abnormal study 
assessment 
• Further diagnostic testing or medical/surgical intervention is required 
• A change in the dose of study drug, if study drug is withheld, or discontinuation from study 
drug occurs 
Repeat testing to determine whether the result is abnormal, in the absence of any of the above 
criteria, does not necessarily meet clinically significant criteria. The determination of whether the 
study assessment results are clinically significant must be made by the Investigator. 
A laboratory abnormality judged to be Grade 4, in itself, may not constitute an SAE unless 
the clinical status of the patient indicates a life-threatening AE. 
Symptoms of the disease under study must not be recorded as AEs as long as they are within the 
normal day-to-day fluctuation or expected progression of the disease, including significant 
worsening unless the deterioration was unexpected, and are part of the efficacy data to be 
collected in the study. 

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7.8. 
Serious Adverse Events 
An AE is considered serious if it meets any of the following: 
• Results in death (regardless of cause, that occurs during participation in the study or occurs 
after participation in the study and is suspected of being a delayed toxicity due to 
administration of the study drug) 
• Is life threatening (an event/reaction in which the patient was at risk of death at the time of 
the event/reaction; it does not refer to an event/reaction which hypothetically might have 
caused death if it were more severe) 
• Requires inpatient hospitalization or prolongation of existing hospitalization 
• Results in persistent or significant disability/incapacity 
• Results in congenital anomaly/birth defect 
• Important medical events that may not result in death, are life-threatening, or require 
hospitalization may be considered serious when, based upon appropriate medical judgment, 
they may jeopardize the patient and may require medical or surgical intervention to prevent 
one of the outcomes (i.e. allergic bronchospasm requiring intensive treatment in an 
emergency room or at home, blood dyscrasias or convulsions that do not result in inpatient 
hospitalization, or the development of drug dependency or drug abuse). 
Clinical outcomes or symptoms related to progressive disease need to be reported as an SAE if 
they meet SAE criteria and occur within 30 days of the last dose of study drug. They must be 
reported according to the diagnosis or symptom of event and not by the term “progressive 
disease.”  
Clarification must be made between the terms "serious" and "severe," because they are not 
synonymous. The term "severe" is often used to describe the intensity (severity) of a specific 
event, as in mild, moderate, or severe myocardial infarction. The event itself, however, may be 
of relatively minor medical significance, such as a severe headache. This is not the same as 
"serious," which is based on patient/event outcome or action criteria described above and is 
usually associated with events that pose a threat to a patient's life or functioning. Seriousness, not 
severity, serves as a guide for defining regulatory reporting obligations. 
7.9. 
Adverse Events of Special Interest for Study Drug 
An AESI is an AE (serious or nonserious) of scientific and medical concern specific to study 
drug, for which ongoing monitoring and immediate notification by the Investigator to the 
Sponsor is required. Such AEs may require further investigation to characterize and understand 
them. AESIs may be added or removed during a study by a protocol amendment. 
The following AEs are considered AESIs: 
• SCC 
• Actinic keratosis 
• Keratoacanthoma 
7.10. 
Adverse Event Reporting Periods 
The AE (including SAEs and AESIs) reporting period begins from the time that the patient 
provides informed consent through and including 30 days after the last dose of the study drug for 

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all randomized patients. Patients who are not randomized will have AEs collected until the time 
of screen failure. Any SAE or AESI occurring after the reporting period must be promptly 
reported if a causal relationship to study drug is suspected.  
If a patient begins a new anticancer therapy, the safety reporting period ends at the time the new 
treatment is started; however, death must always be reported when it occurs during the safety 
reporting period irrespective of intervening treatment. 
7.11. 
Adverse Event, Serious Adverse Event, and Adverse Event of 
Special Interest Reporting Requirements 
Each patient must be carefully monitored for the development of any AEs. This information 
must be obtained in the form of non-leading questions (e.g. “How are you feeling?”) and from 
signs and symptoms detected during each examination, observations of study personnel, and 
spontaneous reports from patients.  
All AEs (serious and non-serious) spontaneously reported by the patient and/or in response to an 
open question from study personnel or revealed by observation, physical examination or other 
diagnostic procedures must be recorded. When possible, signs and symptoms indicating a 
common underlying pathology must be noted as 1 comprehensive event. Accompanying signs or 
symptoms (e.g. abnormal laboratory values) must not be reported as additional AEs. If a 
diagnosis is unknown, one or more symptoms may be reported as separate AEs. If an underlying 
diagnosis is subsequently determined for the reported symptom(s), then the reported symptom(s) 
term(s) must be revised to be “attributed” or “due” to the diagnosis. 
All SAEs and AESIs that occur within the reporting period, regardless of causality, must be 
reported by the Investigator to Sponsor or designee within 24 hours from the point in time when 
the Investigator becomes aware of the SAE or AESI. SAEs and AESIs must be followed until 
resolution, the condition stabilizes, or the Investigator and Sponsor agree that follow up is not 
required. For the purposes of study analysis, if the event has not resolved at the end of the study 
reporting period, it must be documented as ongoing. For purposes of regulatory safety 
monitoring, the Investigator is required to follow the event to resolution and report to the 
Sponsor the outcome of the event. Further instructions on reporting of SAEs will be provided in 
the Study Reference Manual.  
If there are serious unexpected suspected adverse drug reactions (SUSARs) associated with the 
use of the study drug, the Sponsor or authorized designee will ensure that the appropriate 
regulatory agencies and all participating investigators are notified on an expedited basis. In 
addition, the Sponsor or authorized designee will be responsible for notification of SUSARs to 
the ethics committees. It is the responsibility of the Investigator to promptly notify the local 
IRB/IEC/REB of SUSARs according to the institutional policy. An unexpected event is one that 
is not reported in the IB. 
7.12. 
Abuse, Misuse, Overdose, and Medication Error 
Occurrences of events of overdose, drug misuse, drug abuse and medication error must be 
reported to the Sponsor.  
Abuse of a medicinal product: Persistent or sporadic, intentional excessive use of medicinal 
products, which is accompanied by harmful physical or psychological effects [DIR 2001/83/EC 
Art 1(16)]. 

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Misuse: Intentional and inappropriate use of a medicinal product not in accordance with the 
prescribed or authorized dose, route of administration, and/or the indication(s) or not within the 
legal status of its supply. 
Overdose: Administration of a quantity of study drug given per administration or per day, which 
is above the assigned dose. 
Medication Error: An error made in prescribing, dispensing, administration, and/or use of the 
study drug. Medication errors are reportable to the Sponsor as defined below. 
• The dispensing, administration and/or use of the unassigned study drug. 
• The administration and/or use of an expired study drug. 
Note: Cases of patients missing doses of the study drug are not considered reportable as 
medication errors. 
AEs or SAEs associated with drug abuse, misuse, overdose, or medication error must be reported 
as appropriate (Section 7.1 and Section 7.8). 

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8. 
WITHDRAWAL AND REPLACEMENT OF PATIENTS 
8.1. 
End of Treatment 
A patient is free to withdraw from the study drug treatment for any reason and at any time 
without giving reason for doing so and without penalty or prejudice. The Investigator is also free 
to terminate a patient's study drug treatment at any time if the patient's clinical condition 
warrants it. The primary reason for discontinuation or withdrawal of a patient from the study 
drug must be determined using the following categories: 
• Clinical progression 
• Progressive Disease by Independent Radiologic Review 
• Progressive Disease by Investigator Assessment 
• AE 
• Withdrawal by patient from treatment  
• Death 
• Lost to Follow Up 
• Non-compliance with study drug 
• Physician decision 
• Pregnancy 
• Termination of Study by Sponsor 
• Any other reason that in the opinion of the Investigator, would justify removing the 
patient from the study drug, based on the best interest of the patient 
8.2. 
End of Study 
The primary reason for discontinuation or withdrawal of a patient from the study must be 
determined using the following categories: 
• Death 
• Lost to Follow Up 
• Termination of Study by Sponsor 
• Withdrawal by patient from Study 
• Any other reason that in the opinion of the Investigator, would justify removing the 
patient from the study, based on the best interest of the patient 
If a patient voluntarily withdraws from the study, the Investigator should attempt to contact the 
patient to determine the reason(s) for discontinuation and request the patient return for an EOT 
Visit and Safety Follow up Visit. If a patient withdraws from the study for any reason other than 
withdrawal by the patient, an EOT Visit and Safety Follow up Visit must be conducted, and the 
patient must be followed for OS and PFS2. Patients must return all used, partially used, and 
unused study drug bottles. 

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8.3. 
Replacement of Patients 
Patients will not be replaced in this study.  
 
9. 
STATISTICAL CONSIDERATIONS 
9.1. 
Determination of Sample Size 
The sample size selection of 426 patients (n=213 DCC-2618, n=213 sunitinib) was based on 
considerations for powering of the primary endpoint, secondary endpoints, detection of rare 
safety events and overall exposure to DCC-2618. Patients will be randomized in a 1:1 ratio of 
DCC-2618 versus sunitinib. 
Under the assumptions that mPFS is 9 months for DCC-2618 and 6 months for sunitinib, the HR 
is about 0.667 for All Patients (AP) PFS (sunitinib vs DCC-2618). A total of 262 events will be 
required to achieve a statistical power of 90% to test the hypothesis of no difference between 
DCC-2618 and sunitinib in AP. Accrual of 426 patients (213 in DCC-2618 and 213 in sunitinib) 
within 21 months is expected to have 262 PFS events occurred after additional 8 months of 
follow up. This has accounted for 20% of dropout rate (discontinuation without progressive 
disease per IRR or death). 
It is further assumed that the mPFS is 9 months for patients with a KIT Exon 11 primary 
mutation (Ex11) in DCC-2618 and 5 months for KIT Ex11in sunitinib, the HR is 0.556 for the 
KIT Exon11 PFS. It is planned to perform the final analysis on both KIT Ex11 and AP 
populations at the same time. The final analysis is planned to occur when at least 151 PFS events 
in KIT Ex11 population and approximately 262 PFS events in AP population have occurred. The 
151 PFS events in KIT Ex11 population have at least 95% power to test the hypothesis of no 
difference between DCC-2618 and sunitinib in KIT Ex11 population.  
9.2. 
Analysis Endpoints 
9.2.1. 
Primary Endpoint 
The primary and secondary efficacy endpoints will be analyzed for both the Ex11 ITT and AP 
ITT populations (see Section 9.3). 
9.2.1.1. 
Efficacy 
PFS based on independent radiologic review using modified RECIST (mRECIST) 
(Appendix 17.1). mRECIST criteria includes: 
• No lymph nodes chosen as target lesions; enlarged lymph nodes followed as non-target 
lesions;  
• No bone lesions chosen as target lesions;   
• PET not acceptable for radiological evaluation; 
• A progressively growing new tumor nodule within a pre-existing tumor mass must meet the 
following criteria to be considered as unequivocal evidence of progression according to the 
modification of RECIST Version 1.1: (a) the lesion is at least 2 cm in size and definitively a 
new active GIST lesion (e.g. enhancing with contrast or other criteria to rule out artefact); or 
(b) the lesion has to be expanding on at least 2 sequential imaging studies. 

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9.2.2. 
Key Secondary Endpoints 
9.2.2.1. 
Efficacy 
• ORR (confirmed CR + confirmed PR) based on independent radiologic review using 
mRECIST criteria 
• OS 
9.2.2.2. 
Other Secondary Endpoints  
• QOL as measured by using EORTC QLQ-C30, DLQI, and the GP5 question from FACT-G  
• TTP 
• Disease control rate (DCR; CR + PR + SD) at 6, 9 and 12 months, based on independent 
radiologic review 
• PFS based on investigator assessment 
• Efficacy using Choi criteria based on independent radiologic review  
9.2.2.2.1. 
Safety 
Safety endpoints that will be evaluated include treatment-emergent adverse events (TEAEs), 
AESIs, SAEs, dose reduction or discontinuation of study drug due to toxicity; and changes from 
baseline in ECOG PS, vital signs, ECGs, LVEF, dermatologic examinations, and clinical 
laboratory parameters. 
9.2.2.2.2. 
Pharmacokinetics 
• Correlation of PK exposure with efficacy/safety 
• Population-based PK parameters 
9.2.3. 
Exploratory Endpoints 
9.2.3.1. 
Efficacy 
• QOL as measured by EQ-5D-5L, and the memory and concentration items from the PRO-
CTCAE library 
• PFS2: PFS on next line therapy based on local assessments 
• Subgroup analysis for efficacy and other endpoints may be explored as data becomes 
available 
9.2.3.2. 
Biomarkers and Pharmacodynamics 
• Determine the potential innate and acquired resistance mechanisms to DCC-2618 in GIST.  
• Assess KIT/PDGFRA mutations and mutant allele frequency at baseline and the treatment 
effect of DCC-2618 on KIT/PDGFRA mutant allele frequency 
• Evaluate the association of anti-tumor activity/safety of DCC-2618 with the following:  
o baseline KIT/PDFGRA mutation status 

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o expression of KIT protein in tumor 
o expression or polymorphic variation in drug metabolic and/or drug transporter genes  
9.2.3.3. 
Healthcare Utilization 
• Changes over time in healthcare utilization 
9.3. 
Populations for Analysis 
The following populations will be used in the analysis: 
o All Enrolled  
o KIT Exon 11 Intent to Treat (Ex11 ITT)  
o All Patients Intent to Treat (AP ITT) 
o Safety 
o PK 
o KIT Exon 11 Per Protocol (Ex11 PP) 
o All Patients Per Protocol (AP PP) 
The all Enrolled Population is defined as all patients who signed the informed consent and met 
inclusion/exclusion criteria. 
The KIT Exon 11 ITT (Ex11 ITT) Population is defined as all patients who are designated as 
having a mutation in KIT Exon 11 at the time of randomization. Patients in this population will 
be analyzed according to the treatment they were scheduled to receive.  
The AP ITT Population is defined as all patients who are randomized. Patients in this population 
will be analyzed according to the treatment they were scheduled to receive.  
The Safety Population is defined as all patients who are randomized and receive at least one dose 
of study drug.  Safety population will be used for all safety analysis and treatment assignment 
will be based on the actual initial study treatment received.  
The PK Population will include all randomized subjects who received at least 1 dose of DCC-
2618 and had at least 1 non-missing PK concentration in plasma reported for DCC-2618 or DP-
5439.   
The KIT Exon 11 Per Protocol (Ex11 PP) Population is defined as the patients in the Ex11 ITT 
population with at least one post baseline tumor assessment who met all inclusion criteria, did 
not violate any exclusion criteria, and did not have any significant protocol violations/deviations 
considered to impact study integrity. The efficacy analysis on the Ex11 PP population is 
supportive and treatment group will be based on actual treatment received. Protocol violators 
resulting in exclusion from the PP population will be identified and documented prior to database 
lock. 
Note: if a patient has a KIT exon 11 mutation, along with mutation(s) 1) in KIT exon 9 and/or 
PDGFRA, the patient will be randomized as having a KIT exon 11 mutation, unless the mutation 
allele frequency (MAF) data is available then the mutation with the higher MAF will be used to 
categorize the patient for the purposes of randomization; 2) in KIT other exon, the patient will be 
randomized as having a KIT exon 11 mutation.  

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The All Patients Per Protocol (AP PP) population is defined as all patients in AP ITT population 
with at least one post baseline tumor assessment who met all inclusion criteria, did not violate 
any exclusion criteria, and did not have any significant protocol violations/deviations considered 
to impact study integrity. The efficacy analysis on the AP PP population is supportive and 
treatment group will be based on actual treatment received. Protocol violators resulting in 
exclusion from the PP population will be identified and documented prior to database lock. 
9.4. 
Procedures for Handling Missing, Unused, and Spurious Data 
Algorithms for imputing partial or missing dates are shown in Table 16. AE end dates are 
imputed to facilitate calculation of AE duration.  
Table 16: 
Partial or Missing Date Algorithms 
Variable 
Missing Day 
Missing Day, Month 
Missing Day, Month, 
Year 
Date of Last 
Therapy/Date of 
Initial Diagnosis 
Assign 1 
Assign January 1 if prior to date 
of informed consent, otherwise 
use date of informed consent 
Missing (do not impute) 
Adverse 
Event/Start Date 
Assign first day of month 
unless it is the month of first 
dose of study medication. 
Otherwise, assign date of first 
dose of study medication or 
AE end date (if not missing) 
whichever is earlier.  
Assign January 1 unless the year 
is year of first dose of study 
medication. 
Otherwise, assign date of first 
dose of study medication or AE 
end date (if not missing) 
whichever is earlier. 
Assign date first dose of 
study medication. 
Adverse Event 
End Date 
Assign the last day of the 
month or end of study date, 
whichever is earlier.  
Assign December 31 or end of 
study date, whichever is earlier. 
If ongoing, end date is 
missing. Otherwise, 
assign end of study date. 
9.5. 
Interim Analyses 
No interim analyses are planned for the study. 
9.6. 
Adjustment for Multiple Comparisons 
To control familywise type-I error at 0.05 level, the hypothesis tests for treatment difference will 
be performed according to the hierarchical testing sequence below:   
1. 
PFS in Ex11 ITT (two-sided 0.05 level) 
2. 
PFS in AP ITT (two-sided 0.05 level) 
3. 
ORR in Ex 11 ITT (two-sided 0.05 level) 
4. 
ORR in AP ITT (two-sided 0.05 level) 
5. 
OS in Ex11 ITT (two-sided 0.05 level) 
6. 
OS in AP ITT (two-sided 0.05 level) 
The testing starts from PFS in Ex11 ITT and each subsequent endpoint will only be tested if all 
the testing preceding to it have been statistically significant. If the testing for any endpoint fails 
to meet statistical significance, the testing and p-value for all the subsequent endpoints will be 
nominal and statistical significance won’t be claimed for all the subsequent endpoints. 

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9.7. 
Blinding 
This is an open-label study. 
9.8. 
Statistical Methods 
9.8.1. 
General Methods 
Data collected in this study will be documented using summary tables and patient data listings. 
Continuous variables will be summarized using descriptive statistics (number of patients, mean, 
median, standard deviation, minimum, and maximum). Categorical variables will be summarized 
using frequencies and proportions. Time-to-event data will be summarized via Kaplan-Meier 
(KM) methodology using the 25th, 50th (median), and 75th percentiles with associated 2-sided 
95% confidence intervals. 
Unless specified otherwise, baseline measurements must be the most recent value prior to 
receiving the first dose of study medication. If an assessment is not available, then the last 
assessment prior to that visit would be used.  
Medical history, AEs, and concurrent procedures will be coded using Medical Dictionary for 
Regulatory Activities (MedDRA). Prior and concomitant medications will be coded using the 
World Health Organization Drug Dictionary. 
Unless specified, the ITT population is used for efficacy analysis and the safety population is 
used for the safety analysis. The primary and secondary efficacy endpoints will be analyzed for 
both the Ex11 ITT and the AP ITT populations.  
9.8.2. 
Disposition of Patients 
Patient disposition will be summarized overall for all patients who entered the study (i.e. signed 
the informed consent for the study and met inclusion/exclusion criteria). The number of patients 
in each population (enrolled, safety, PK, ITT, PP if applicable) and patients were removed from 
a population will be displayed. The number and proportion of patients who complete the study, 
as well as those who discontinue the study will be summarized along with the reason for 
discontinuation. 
9.8.3. 
Demographic and Baseline Characteristics 
Demographic and baseline characteristics (including risk assessment for recurrence at study 
entry) will be summarized by for the Safety, ITT, and PP populations (35). 
Medical history will be summarized overall for the Safety population. 
9.8.4. 
Extent of Exposure 
The total number of patients who received study medication will be summarized by n and 
percentage. In addition, the number of cycles received will be displayed using continuous 
descriptive statistics. These analyses will be performed for the Safety population. 

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9.8.5. 
Efficacy Analysis 
9.8.5.1. 
Primary Endpoint: Progression-Free Survival Analysis 
The primary endpoint of PFS is defined as the interval between the date of randomization and the 
earliest documented evidence of disease progression based on the independent radiologic review, 
or death due to any cause. Patients who undergo surgical resection of target or non-target lesions, 
who have received other anticancer treatments for GIST, or patients who do not have a 
documented date of progression or death due to any cause will be censored at the date of the last 
assessment.  
Analysis for PFS in AP ITT will be stratified by the randomization stratification factors 
(mutation status [KIT exon 9 vs. KIT exon 11 vs. KIT/PDGFRA WT vs. other KIT {absence of 
exon 9 or 11}/PDGFRA] and intolerance to imatinib [yes vs. no]). Analysis for PFS in Ex11 ITT 
will be stratified by intolerance to imatinib [yes vs. no]. The p-value will be from a 2-sided 
stratified Log-rank test at 0.05 significance level for evaluation of treatment difference. Point 
estimate of hazard ratio will be obtained from a Cox regression model with treatment and the 
randomization stratification factors as fixed factors and the associated 95% CI will be obtained 
using the Wald method. Median progression free survival time (mPFS) with 95% confidence 
interval will also be presented by treatment using KM methodology. 
NOTE:  
Rules of defining PFS events and censoring PFS will be elaborated in the statistical analysis plan 
(SAP). Sensitivity analysis for PFS will be specified in the SAP. 
Analysis will be using the ITT population as the primary analysis and PP as supportive. 
Progression free survival will have sensitivity analyses performed which will be further detailed 
in the SAP. 
9.8.5.2. 
Secondary Efficacy Endpoints 
9.8.5.2.1. 
Objective Response Rate Analysis 
ORR is defined as the proportion of patients with a confirmed CR or PR based on the 
independent radiologic review. This analysis will be performed in the ITT population as the 
primary analysis and the PP population as supportive analysis. To be assigned a status of a CR or 
PR, changes in tumor measurements must be confirmed by repeat assessments that must be 
performed at least 4 weeks after the criteria for response are first met. Patients with unknown or 
missing response will be treated as non-responders, that is, they will be included in the 
denominator when calculating the proportion.  
Analysis for ORR in AP ITT population will be stratified by the randomization stratification 
factors (mutation status [KIT exon 9 vs. KIT exon 11 vs. KIT/PDGFRA WT vs. other KIT 
{absence of exon 9 or 11}/PDGFRA] and intolerance to imatinib [yes vs. no]). Analysis for ORR 
in Ex11 ITT population will be stratified by intolerance to imatinib [yes vs. no]. For each 
population, the p-value will be based on a Cochran Mantel-Haenszel chi-square test for the  
association between treatment and ORR at 0.05 significance level; stratified Newcombe 95% 
confidence limits will be calculated for the difference in ORR between the treatment arms. 

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9.8.5.2.2. 
Overall Survival 
OS is defined as the interval between the date of randomization and date of death from any 
cause. Patients who are still alive or who are lost to follow-up will be censored at the date of last 
contact. OS will be analyzed using similar model as PFS and will be analyzed based on both 
Ex11 ITT and AP ITT separately.  
9.8.5.2.3. 
EORTC QLQ-C30 
The EORTC QLQ C30 will be summarized by scales per the manual and treatments compared 
by role and physical function for both Ex11 ITT and AP ITT separately. 
9.8.5.2.4. 
DLQI 
The total score for the DLQI will be calculated by summing the score of each question for both 
Ex11 ITT and AP ITT separately, per the scoring manual (see 
http://sites.cardiff.ac.uk/dermatology/quality-of-life/dermatology-quality-of-life-index-dlqi/dlqi-
instructions-for-use-and-scoring/). Higher scores are associated with a lower the quality of life. 
The total score will be summarized using descriptive statistics, including proportions who are 
moderately impacted (a total score of six to ten points) and severely impacted (a score of eleven 
or more). In addition to the total score, continuous descriptive statistics will also be displayed by 
section as follows: 
Section 
Questions Included 
Symptoms and Feelings 
1,2 
Daily Activities 
3,4 
Leisure 
5,6 
Work and School 
7 
Personal Relationships 
8,9 
Treatment 
10 
 
9.8.5.2.5. 
GP5 Question from FACT-G 
FACT-G: Functional Assessment of Cancer Therapy - General - is a validated and widely used 
questionnaire that can be used with cancer patients of any tumor type. It includes a question 
referred to as GP5 which asks, "I am bothered by side effects of treatment". The answer is 
provided by the patient who selects one of the following five choices: Not at all, A little bit, 
Some-what, Quite a bit, or Very much. 
Effect sizes for the difference in mean GP5 scores between groups can be estimated as the mean 
difference divided by the pooled standard deviation.  FACT-G will be summarized for both Ex 
11 ITT and AP ITT separately. 
9.8.5.2.6. 
Time to Tumor Progression  
The secondary endpoint of TTP is defined as the interval between the date of randomization and 
the earliest documented evidence of disease progression based on the independent radiologic 
review. Patients who undergo surgical resection of target or non-target lesions, who have 
received other anticancer treatments for GIST, who do not have a documented date of 
progression or death due to any cause, or who die prior to tumor progression will be censored at 

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the date of the last assessment. TTP will be analyzed using similar model as PFS for both Ex 11 
ITT and AP ITT separately.  
9.8.5.2.7. 
Disease Control Rate Analysis 
DCR will be calculated and summarized with n and percentage at 6, 9, and 12 months. Disease 
control will be defined as having a response (complete or partial) or SD. Fisher’s Exact test will 
be used to investigate statistical differences between treatment groups for both Ex 11 ITT and 
AP ITT separately. 
9.8.5.2.8. 
Progression-free Survival based on Investigator Assessment 
PFS is defined as the interval between the date of randomization and the earliest documented 
evidence of disease progression based on Investigator assessment, or death due to any cause. 
Differences between treatment groups will be evaluated using the same methodology as for the 
primary endpoint for both Ex11 ITT and AP ITT separately. 
9.8.5.2.9. 
Efficacy Based on Choi Criteria Based on Independent Radiologic Review 
The primary PFS, ORR, TTP, and DCR analyses will be repeated using the Choi criteria in place 
of mRECIST for both Ex11 ITT and AP ITT separately.  
9.8.5.3. 
Exploratory Endpoints 
9.8.5.3.1. Memory and Concentration Items from PRO-CTCAE Library 
The Memory and Concentration Items from the PRO-CTCAE Library will be summarized with n 
and percentage for each question. 
9.8.5.3.2. 
EQ-5D-5L 
The EQ-5D-5L will be summarized overall by n and percentage for each level of each 
dimension. The Cochran–Mantel–Haenszel test will be used to test differences between DCC-
2618 and sunitinib. The EQ-VAS will be summarized using continuous descriptive statistics.  
9.8.5.3.3. 
Efficacy 
• Progression free survival on the next line of therapy (PFS2) will analyze time from the 
start of next therapy  
• to the progression or death on the next line of therapy using the same methods used for 
the primary analysis of PFS. 
• Subgroup analysis may be done as data becomes available. 
9.8.5.3.4. 
Biomarkers and Pharmacodynamics 
• Determine the potential innate and acquired resistance mechanisms to DCC-2618 in 
GIST.  
• Assess KIT/PDFGRA mutations and mutant allele frequency at baseline and the 
treatment effect of DCC-2618 on KIT/PDGFRA mutant allele frequency.  
• Evaluate the association of anti-tumor activity/safety of DCC-2618 with the following:  
o baseline KIT/PDFGRA mutation status 
o expression of KIT protein in tumor 

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o expression or polymorphic variation in drug metabolic and/or drug transporter genes 
9.8.6. 
Safety Analysis 
9.8.6.1. 
Adverse Events 
AEs will be summarized utilizing the number of events and proportion of patients overall, by 
system organ class (SOC) and preferred term for the Safety population. All tables will only 
include TEAEs, where treatment emergent is defined as any AE that occurs after administration 
of the first dose of study drug and through 30 days after the last dose of study drug, but data 
listings will include all collected AEs.  
AE toxicity grade will be classified using NCI-CTCAE Version 5.0 criteria (See Table 12). If a 
patient has multiple occurrences of the same SOC or preferred term, then only the most severe 
event will be summarized in the tables for that SOC and preferred term. AEs of ≥ Grade 3 will 
also be summarized. A missing toxicity grade will not be imputed. 
The AE analysis will be repeated for SAEs, AEs leading to dose reduction or discontinuation, 
and AESIs.  
No formal hypothesis-testing analysis of AE incidence rates will be performed.  
9.8.6.2. 
Eastern Cooperative Oncology Group Performance Status 
Baseline, post baseline, and change at post baseline from baseline values will be summarized by 
time point utilizing descriptive statistics. No formal hypothesis-testing analysis will be 
performed. 
9.8.6.3. 
Vital Signs 
Assessments will be summarized overall by time point utilizing continuous descriptive statistics. 
In addition, the change from baseline will be summarized for continuous parameters. For 
categorical parameters, the n and percentage will be displayed. No formal hypothesis-testing 
analysis will be performed. 
9.8.6.4. 
Echocardiogram/Multigated Acquisition Scans 
Assessments will be summarized overall by time point utilizing continuous descriptive statistics. 
In addition, the change from baseline will be summarized for continuous parameters. For 
categorical parameters, the n and percentage will be displayed. No formal hypothesis-testing 
analysis will be performed. 
9.8.6.5. 
Dermatologic Assessments  
Dermatologic assessments will be summarized by descriptive statistics. No formal 
hypothesis-testing analysis will be performed. 
9.8.6.6. 
Clinical Laboratory Parameters 
Assessments will be summarized overall by time point utilizing continuous descriptive statistics. 
In addition, the change from baseline will be summarized for continuous parameters. For 
categorical parameters, the n and percentage will be displayed. No formal hypothesis-testing 
analysis will be performed. 

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11. 
QUALITY CONTROL AND QUALITY ASSURANCE 
11.1. 
Study Site Monitoring Visits 
During study conduct, the Sponsor or its agent will conduct periodic monitoring visits to ensure 
that the protocol and ICH GCPs are being followed. The monitors will review source documents 
to confirm that the data recorded on eCRFs is accurate. The Investigator and institution will 
allow the Sponsor’s monitors or designees and appropriate regulatory authorities direct access to 
source documents to perform this verification. 
The study site may be subject to review by the IRB/IEC/REB, and/or to quality assurance audits 
performed by the Sponsor, or companies working with or on behalf of the Sponsor, and/or to 
inspection by appropriate regulatory authorities. 
It is important that the Investigator and their relevant personnel are available during the 
monitoring visits and possible audits or inspections and that sufficient time is devoted to the 
process. 
11.2. 
Protocol Compliance 
The Investigator must conduct the study in compliance with the protocol provided by the 
Sponsor and given approval/favorable opinion by the IRB/IEC/REB and the appropriate 
regulatory authorities. Modifications to the protocol must not be made without agreement 
between both the Investigator and the Sponsor. Changes to the protocol will require written 
IRB/IEC/REB and the appropriate regulatory authority(ies) approval/favorable opinion prior to 
implementation, except when the modification is needed to eliminate an immediate hazard(s) to 
patients. The IRB/IEC/REB may provide, if applicable regulatory authority(ies) permit, 
expedited review and approval/favorable opinion for minor change(s) in ongoing studies that 
have the approval/favorable opinion of the IRB/IEC/REB. The Sponsor must ensure that all 
protocol modifications are submitted to the regulatory authority(ies) in accordance with the 
governing regulations.  
If other unexpected circumstances arise that require deviation from protocol-specified 
procedures, the Investigator must consult with the Sponsor (and IRB, IEC, or REB, as required) 
to determine the appropriate course of action. 
The site must document all protocol deviations in the patient’s source documents. In the event of 
a significant deviation, the site must notify the Sponsor (and IRB, IEC, or REB, as required). 
Significant deviations include, but are not limited to, those that involve fraud or misconduct, 
increase the health risk to the patient, or confound interpretation of primary study assessments. 

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12. 
DATA HANDLING AND RECORD KEEPING 
12.1. 
Electronic Case Report Form 
The Sponsor or designee will provide the study sites with secure access to and training on the 
electronic data capture application sufficient to permit site personnel to enter or correct 
information in the eCRFs on the patients for which they are responsible. 
An eCRF is required and must be completed for each randomized patient. The Investigator has 
ultimate responsibility for the accuracy, authenticity, and timely collection and reporting of all 
clinical, safety, and laboratory data entered on the eCRFs and any other data collection forms. 
Source documentation supporting the eCRF data must indicate the patient’s participation in the 
study and must document the dates and details of study procedures, AEs, other observations, and 
patient status. 
The Investigator, or designated representative, must complete the eCRF as soon as possible after 
information is collected. 
The audit trail will show the user’s identification information and the date and time of the any 
correction. The eCRFs must be signed electronically by the Investigator to attest that the data 
contained on the eCRFs, including any changes made to the eCRFs, is correct and endorse the 
final submitted data for the patients for whom the Investigator is responsible. 
The completed eCRFs are the sole property of the Sponsor and must not be made available in 
any form to third parties, except for authorized representatives of the Sponsor or appropriate 
regulatory authorities, without written permission from the Sponsor. 
The Sponsor will retain the eCRF data and corresponding audit trails. A copy of the final 
archival eCRF in the form of a compact disc or other electronic media will be provided to the site 
for placement in the Investigator’s study file. 
12.2. 
Record Retention 
To enable evaluations and/or audits from regulatory authorities or the Sponsor, the Investigator 
agrees to keep records, including the identity of all participating patients (sufficient information 
to link records, e.g. eCRFs and hospital records), all original signed ICFs, eCRFs, SAE forms, 
source documents, detailed records of treatment disposition, and adequate documentation of 
relevant correspondence (e.g. letters, meeting minutes, telephone calls reports). The records must 
be retained by the Investigator according to the ICH, local regulations, or as specified in the 
Clinical Study Agreement, whichever is longer. 
If the Investigator becomes unable for any reason to continue to retain study records for the 
required period (e.g. retirement, relocation), the Sponsor must be prospectively notified. The 
study records must be transferred to a designee acceptable to the Sponsor, such as another 
Investigator, another institution, or to the Sponsor. The Investigator must obtain the Sponsor's 
written permission before disposing of any records, even if retention requirements have been 
met. 

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13. 
ETHICS 
13.1. 
Ethical Conduct of the Study 
The study will be conducted in accordance with the Declaration of Helsinki on Ethical Principles 
for Medical Research Involving Human Subjects, adopted by the General Assembly of the World 
Medical Association (28).  
In addition, the study will be conducted in accordance with the protocol, ICH GCP, and 
applicable local regulatory requirements and laws. 
The Investigator must ensure that this study is conducted in full conformity with Regulations for 
the Protection of Human Subjects of Research codified in 21 CFR Part 50, 21 CFR Part 54, 21 
CFR Part 56, 21CFR Part 312, 21 CFR Part 314 and ICH GCP E6. 
13.2. 
Patient Information and Consent 
All parties must ensure protection of patient personal data and must not include patient names on 
any Sponsor forms, reports, publications, or in any other disclosures, except where required by 
laws. In case of data transfer, the Sponsor must maintain high standards of confidentiality and 
protection of patient personal data. 
The ICF must be in compliance with ICH GCP, local regulatory requirements, and legal 
requirements. 
The ICF used in this study, and any changes made during the course of the study, must be 
prospectively approved by both the IRB/IEC/REB and the Sponsor before use. 
The Investigator must ensure that each study patient is fully informed about the nature and 
objectives of the study and possible risks associated with participation. The Investigator, or a 
person designated by the Investigator, must obtain written informed consent from each patient 
before any study-specific activity is performed. The Investigator must retain the original of each 
patient's signed consent form. 
13.3. 
IRB/IEC/REB 
It is the responsibility of the Investigator to have prospective approval of the study protocol, 
protocol amendments, ICF, and other relevant documents, (e.g. recruitment advertisements, if 
applicable) from the IRB/IEC/REB. All correspondence with the IRB/IEC/REB must be retained 
in the Investigator Site File. 
The only circumstance in which an amendment may be initiated prior to IRB/IEC/REB approval 
is where the change is necessary to eliminate apparent immediate hazards to the patients. In that 
event, the Investigator must notify the IRB/IEC/REB and the Sponsor in writing immediately 
after the implementation. 
13.4. 
Patient Confidentiality 
The Sponsor and designees affirm and uphold the principle of the patient’s right to protection 
against invasion of privacy. Throughout this study, a patient’s source data must only be linked to 
the Sponsor’s clinical study database or documentation via a unique identification number. As 
permitted by all applicable laws and regulations, limited patient attributes, such as sex, age, or 
date of birth may be used to verify the patient and accuracy of the patient’s unique identification 
number. 

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To comply with ICH GCP and to verify compliance with this protocol, the Sponsor requires the 
Investigator to permit its monitor or designee’s monitor, representatives from any regulatory 
authority (e.g. FDA), the Sponsor’s designated auditors, and the appropriate IRBs/IECs/REBs to 
review the patient’s original medical records (source data or documents), including, but not 
limited to, any genetic/genomic data the patient might have from testing done prior to entering 
the study, laboratory test result reports, ECG reports, admission and discharge summaries for 
hospital admissions occurring during a patient’s study participation, and autopsy reports. Access 
to a patient’s original medical records requires the specific authorization of the patient as part of 
the informed consent process (Section 13.2). 
Copies of any patient source documents that are provided to the Sponsor must have certain 
personally identifiable information removed (i.e. patient name, address, and other identifier 
fields not collected on the patient’s eCRF). 
13.5. 
Reporting of Safety Issues or Serious Breaches of the Protocol or 
International Conference on Harmonization Good Clinical Practice 
In the event of any prohibition or restriction imposed (i.e. clinical hold) by an applicable 
Competent Authority, or if the Investigator is aware of any new information which might 
influence the evaluation of the benefits and risks of the study drug, the Sponsor must be 
informed immediately.  
In addition, the Investigator must inform the Sponsor immediately of any urgent safety measures 
taken by the Investigator to protect the study patients against any immediate hazard, and of any 
serious breaches of this protocol or of ICH GCP that comes to the attention of the Investigator. 
13.6. 
Liability and Insurance 
The Sponsor has subscribed to an insurance policy covering, in its terms and provisions, its legal 
liability for injuries caused to participating persons and arising out of this research performed 
strictly in accordance with the scientific protocol as well as with applicable law and professional 
standards. 
 

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14. 
STUDY TERMINATION 
When the Sponsor is aware of information on matters concerning the quality, efficacy, and safety 
of the study drug, as well as other important information that may affect proper conduct of the 
clinical study, the Sponsor may discontinue the clinical study and send a written notice of the 
discontinuation along with the reason to the Investigator.  
If an Investigator intends to discontinue participation in the study, the Investigator must 
immediately inform the Sponsor of the discontinuation and the reason for it. 
14.1. 
Criteria for Suspension or Premature Termination of the Study 
Criteria for either temporary suspension or premature termination of the study include: 
1. New information regarding the safety or efficacy of the study drug that indicates a change in 
the known risk/benefit profile for the compound, such that the risk/benefit is no longer 
acceptable for patients participating in the study. 
2. Significant violation of GCP that compromises the ability to achieve the primary study 
objectives or compromises patient safety. 
3. The Sponsor may suspend or prematurely terminate the study for reasons not related to the 
conduct of the study. 
14.2. 
Criteria for Premature Termination or Suspension of Investigational 
Sites 
A study site may be terminated prematurely or suspended if the site (including the Investigator) 
is found to be in significant violation of GCP, protocol, contractual agreement, or is unable to 
ensure adequate performance of the study. 
14.3. 
Procedures for Premature Termination or Suspension of the Study 
or the Participation of Investigational Site(s) 
In the event that the Sponsor elects to terminate or suspend the study or the participation of an 
investigational site, a study-specific procedure for early termination or suspension will be 
provided by the Sponsor. The procedure will be followed by applicable investigational sites 
during the course of termination or study suspension. 

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15. 
PUBLICATION OF STUDY RESULTS 
Any and all scientific, commercial, and technical information disclosed by the Sponsor in this 
protocol or elsewhere must be considered the confidential and proprietary property of the 
Sponsor. The Investigator shall hold such information in confidence and shall not disclose the 
information to any third party except to such of the Investigator's employees and staff as have 
been made aware that the information is confidential and who are bound to treat it as such and to 
whom disclosure is necessary to evaluate that information. The Investigator shall not use such 
information for any purpose other than determining mutual interest in performing the study and, 
if the parties decide to proceed with the study, for the purpose of conducting the study. 
The Investigator understands that the information developed from this clinical study will be used 
by the Sponsor in connection with the development of the study drug and therefore may be 
disclosed as required to other clinical investigators, business partners and associates, the FDA, 
and other government agencies. The Investigator also understands that, to allow for the use of the 
information derived from the clinical study, the Investigator has the obligation to provide the 
Sponsor with complete test results and all data developed in the study. 
No publication or disclosure of study results will be permitted except under the terms and 
conditions of a separate written agreement between the Sponsor and the Investigator and/or the 
Investigator's institution. 
 
 

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17. 
APPENDICES 
17.1. 
Modified Response Evaluation Criteria in Solid Tumors 
(mRECIST) 
mRECIST criteria includes: 
• No lymph nodes chosen as target lesions; enlarged lymph nodes followed as non-target 
lesions;  
• No bone lesions chosen as target lesions;   
• Positron emission tomography (PET) not acceptable for radiological evaluation; 
• A progressively growing new tumor nodule within a pre-existing tumor mass must meet 
the following criteria to be considered as unequivocal evidence of progression according 
to the modification of RECIST Version 1.1: (a) the lesion is at least 2 cm in size and 
definitively a new active GIST lesion (e.g. enhancing with contrast or other criteria to 
rule out artefact); or (b) the lesion has to be expanding on at least 2 sequential imaging 
studies. 
Source: Demetri GD, Reichardt P, Kang YK, Blay JY, Rutkowski P,Gelderblom H, Hohenberger P, Leahy M, von Mehren 
M, Joensuu H, BadalamentiG, Blackstein M, Le Cesne A, Schöffski P, Maki RG, Bauer S, Nguyen BB, Xu J, Nishida T, 
Chung J, Kappeler C, Kuss I, Laurent D, Casali PG; GRID study investigators. Efficacy and safety of regorafenib for 
advanced gastrointestinal stromal tumours after failure of imatinib and sunitinib (GRID): an international, multicentre, 
randomised, placebo-controlled, phase 3 trial. Lancet. 2013 Jan26;381(9863):295-302.