A Phase 3 interventional study of IDRX-42 and Sunitinib in Gastrointestinal Neoplasms, sponsored by GlaxoSmithKline. Recruiting at 156 sites in 19 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-05.
Sponsored by GlaxoSmithKline · Phase 3, Interventional, and Treatment
The purpose of this study is to find out if a new drug, called IDRX-42 (also known as GSK6042981), is effective in treating adults with a type of cancer called Gastrointestinal Stromal Tumors (GIST) when compared to another drug named sunitinib. The study will see if IDRX-42 works well and is safe for participants whose GIST has spread or cannot be surgically removed, and who have already taken the drug imatinib. Participants whose disease worsens after receiving sunitinib in this study may cross over to receive GSK6042981, at investigator's discretion and if additional eligibility criteria are met.
343 studies on the registry are indexed under Gastrointestinal Stromal Tumors; 61 are open to participants now.
This study's planned enrollment of 450 is above the median of 50 across 252 interventional studies indexed under Gastrointestinal Stromal Tumors.
Browse Gastrointestinal Stromal Tumors studies →GlaxoSmithKline is the lead sponsor of 3,650 studies on the registry; 118 are open to participants now.
Of its 264 completed or terminated interventional studies of FDA-regulated products, 241 (91%) have results posted.
Compared within Gastrointestinal Stromal Tumors, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Gastrointestinal Neoplasms. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Line of therapy
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: IDRX-42
Drug: Sunitinib
Progression-Free Survival (PFS)
PFS is defined as time from the date of randomization to the date of disease progression or death due to any cause, whichever occurs first.
Time frame: Up to approximately 130 weeks
Overall Survival (OS)
OS is defined as time from the date of randomization to the date of death due to any cause.
Time frame: Up to approximately 261 weeks
Progression-Free Survival (PFS)
PFS is defined as time from the date of randomization to the date of disease progression or death due to any cause, whichever occurs first.
Time frame: Up to approximately 261 weeks
Confirmed Overall Objective Response Rate (ORR)
ORR is defined as the percentage of participants with the best overall confirmed partial response (PR) or complete response (CR).
Time frame: Up to approximately 261 weeks
Time to Response (TTR)
TTR is defined as time from randomization until the first documented PR or complete response (CR) that will be subsequently confirmed.
Time frame: Up to approximately 261 weeks
Time from initial study randomization to second disease progression or death after starting the next line of treatment (PFS2)
PFS2 is defined as the time from initial study randomization to the disease progression following first subsequent anticancer therapy or death, whichever is first.
Time frame: Up to approximately 261 weeks
Change From Baseline in European Organization for Research and Treatment of Cancer Quality of Life Questionnaire 30-item Core Module (EORTC QLQ-C30)
The EORTC QLQ-C30 includes 30-item questionnaire for evaluating the health-related quality of life (HRQoL) of participants participating in cancer clinical studies. These include functional scales, symptom scales, global health status scale, and single item scales. Scores are averaged and transformed to 0 to 100. Higher scores indicate greater functioning, better global health status, or more severe symptoms
Time frame: Baseline (Day 1) and up to approximately 261 weeks
Time To Confirmed Deterioration (TTCD)
TTCD is defined as the time from the date of randomization to the first confirmed clinically meaningful deterioration based on the EORTC QLQ-C30.
Time frame: Up to approximately 261 weeks
Plasma concentrations of IDRX-42 (GSK6042981)
Time frame: Up to approximately 261 weeks
Number of Participants with Treatment Emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs)
Time frame: Up to approximately 261 weeks
Number of Participants with TEAEs and SAEs by severity
Time frame: Up to approximately 261 weeks
Number of Participants with dose reductions, interruptions and discontinuation of study treatment due to toxicity
Time frame: Up to approximately 261 weeks
Number of participants with symptomatic adverse events (AEs), by severity, as measured by the Patient-reported outcome Common Terminology Criteria for Adverse Events (PRO-CTCAE)
The PRO-CTCAE is a patient-reported outcome measure developed to evaluate symptomatic toxicities in participants in cancer clinical trials. The PRO-CTCAE includes an item library of 124 items representing 78 symptomatic toxicities drawn from the CTCAE.
Time frame: Up to approximately 261 weeks
Number of participants with bothersome AEs/tolerability as measured by the Functional Assessment of Cancer Therapy - General (FACT-GP5)
The FACT GP5 is an assessment focused on the overall side effects impact to inform the tolerability of a treatment. The FACT GP5 ("I am bothered by side effects of treatment") responses are given on a 5-point Likert type scale. The response scale ranges from 0 (Not at all) to 4 (Very much). Higher scores indicate a higher degree of AE bother.
Time frame: Up to approximately 261 weeks
Showing the first 100 of 156 sites across 19 countries. Choose a country and city above to see the rest.
Plan to share: No — GSK will assess requests from qualified researchers for anonymized individual patient-level data and related study documents. Data sharing is subject to certain criteria, conditions, and exceptions. For further information, refer to https://www.gsk-studyregister.com/gsk-patient-level-data-sharing-july2025.pdf
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
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Studies of the drug tested here: IDRX-42
Gastrointestinal Stromal Tumors →