A Phase 2 interventional study of Temozolomide in Gastrointestinal Stromal Tumors, Sdh and GIST, sponsored by Adam Burgoyne, MD, PhD. Completed at 4 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-28.
Sponsored by Adam Burgoyne, MD, PhD · Phase 2, Interventional, and Treatment
Funding Source - FDA OOPD
FDA-approved products for patients with unresectable or metastatic GIST include therapies such as imatinib and sunitinib. Although there are FDA-approved products for the treatment of advanced/metastatic GIST, these therapies are known to be ineffective in the SDH-mutant/deficient subtype and no known effective therapies exist.
The purpose of this study is to investigate SDH-Mutant/Deficient Gastrointestinal Stromal cancer's response to the drug Temozolomide (TMZ) and aim to improve patient outcomes.
Temozolomide is approved by the FDA for the treatment of newly diagnosed glioblastoma multiforme (GBM) and refractory anaplastic astrocytoma cancers.
Temozolomide is considered experimental because it is not approved by the FDA for the treatment of SDH-Mutant/Deficient Gastrointestinal Stromal Tumor.
This oncology study will be a phase 2 study for patients with advanced or metastatic GIST. This study will determine overall response rate at 6 months for TMZ therapy in patients with SDH-mutant/deficient GIST.
Treatment will continue for 6 months (with option to continue if benefiting treatment) or until disease progression or unacceptable toxicity (whichever occurs first). All patients will have regular evaluations for assessment of safety parameters. Temozolomide dose may be held and/or modified for the management of adverse treatment effects according to pre-specified criteria. Patients will have radiographic imaging (CT or MRI) every 8 weeks to assess tumor resection.
An end of treatment visit for clinical evaluations and safety assessments will be performed approximately 28 days (7 days) after the last dose of study drug. Patients discontinuing study treatment will be followed every 3-6 months for disease recurrence and survival.
343 studies on the registry are indexed under Gastrointestinal Stromal Tumors; 61 are open to participants now.
This study's enrollment of 23 is below the median of 50 across 252 interventional studies indexed under Gastrointestinal Stromal Tumors.
Browse Gastrointestinal Stromal Tumors studies →This is the only study on the registry with Adam Burgoyne, MD, PhD as lead sponsor.
Counted across the registry records on this site, refreshed daily.
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.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
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.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Brain metastases
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CTCAE grade
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TMZ 85 mg/m2 mg orally once for 21 days followed by 7 days without treatment in 28 day cycles. Treatment will continue for 6 months (with option to continue if benefiting treatment) or until disease progression or unacceptable toxicity (whichever occurs first). All patients will have regular evaluations for assessment of safety parameters. Temozolomide dose may be held and/or modified for the management of adverse treatment effects according to pre-specified criteria. Patients will have radiographic imaging (CT or MRI) every 8 weeks to assess tumor resection. An end of treatment visit for clinical evaluations and safety assessments will be performed approximately 28 days after the last dose of study drug. Patients discontinuing study treatment will be followed every 3-6 months for disease recurrence and survival.
Drug: Temozolomide
Temozolomide 85 mg/m2 will be administered orally for 21 days followed by 7 days without treatment in 28 day cycles. Treatment will continue for 6 months (with option to continue if benefiting treatment) or until disease progression or unacceptable toxicity (whichever occurs first). All patients will have regular evaluations for assessment of safety parameters
Also known as: TEMODAR®
Overall Response Rate
To determine overall response rate at 6 months for TMZ therapy in patients with SDH-mutant/deficient GIST. Per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) for target lesions and assessed by MRI: Complete Response (CR), Disappearance of all target lesions; Partial Response (PR), \>=30% decrease in the sum of the longest diameter of target lesions; Overall Response (OR) = CR + PR.
Time frame: 6 months
Progression-free Survival
Progression-free survival. Progression is defined using Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1), as a 20% increase in the sum of the longest diameter of target lesions, or a measurable increase in a non-target lesion, or the appearance of new lesions.
Time frame: 30 months
Overall Survival
Number of participants alive
Time frame: 40 months
Adverse Events and Serious Adverse Events
Number of participants with adverse events and serious adverse events
Time frame: 40 months
| Milestone | TMZ 85 mg/m2 mg Orally |
|---|---|
| Started | 23 |
| Completed | 23 |
| Not completed | 0 |
To determine overall response rate at 6 months for TMZ therapy in patients with SDH-mutant/deficient GIST. Per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) for target lesions and assessed by MRI: Complete Response (CR), Disappearance of all target lesions; Partial Response (PR), \>=30% decrease in the sum of the longest diameter of target lesions; Overall Response (OR) = CR + PR.
| participants | TMZ 85 mg/m2 mg Orally |
|---|---|
| Overall Response Rate | 2 |
Progression-free survival. Progression is defined using Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1), as a 20% increase in the sum of the longest diameter of target lesions, or a measurable increase in a non-target lesion, or the appearance of new lesions.
| months | TMZ 85 mg/m2 mg Orally |
|---|---|
| Progression-free Survival | 16.5 (6.2 to NA) |
Number of participants alive
| Participants | TMZ 85 mg/m2 mg Orally |
|---|---|
| Overall Survival | 19 |
Number of participants with adverse events and serious adverse events
| Participants | TMZ 85 mg/m2 mg Orally |
|---|---|
| Adverse Events and Serious Adverse Events | 23 |
Collected over 40 months. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| TMZ 85 mg/m2 mg Orally | 5/23 (21.7%) | 8/23 (34.8%) | 23/23 (100%) |
| Event | TMZ 85 mg/m2 mg Orally |
|---|---|
| Platelet count decreasedBlood and lymphatic system disorders | 3/23 |
| VomitingGastrointestinal disorders | 1/23 |
| HyponatremiaMetabolism and nutrition disorders | 1/23 |
| PainGeneral disorders | 1/23 |
| Edema LimbsGeneral disorders | 1/23 |
| SepsisInfections and infestations | 1/23 |
| Flank PainGeneral disorders | 1/23 |
| Event | TMZ 85 mg/m2 mg Orally |
|---|---|
| NauseaGastrointestinal disorders | 17/23 |
| FatigueGeneral disorders | 14/23 |
| VomitingGastrointestinal disorders | 14/23 |
| Lymphocyte count decreasedBlood and lymphatic system disorders | 12/23 |
| ConstipationGastrointestinal disorders | 10/23 |
| AnemiaBlood and lymphatic system disorders | 9/23 |
| DiarrheaGastrointestinal disorders | 9/23 |
| Abdominal painGastrointestinal disorders | 8/23 |
| Neutrophil count decreasedBlood and lymphatic system disorders | 8/23 |
| White blood cell decreasedBlood and lymphatic system disorders | 6/23 |
| Age, Continuous(years) | TMZ 85 mg/m2 mg Orally |
|---|---|
| Mean | 42.43 ± 15.62 |
| Sex: Female, Male(Participants) | TMZ 85 mg/m2 mg Orally |
|---|---|
| Female | 10 |
| Male | 13 |
| Ethnicity (NIH/OMB)(Participants) | TMZ 85 mg/m2 mg Orally |
|---|---|
| Hispanic or Latino | 3 |
| Not Hispanic or Latino | 19 |
| Unknown or Not Reported | 1 |
| Race (NIH/OMB)(Participants) | TMZ 85 mg/m2 mg Orally |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 2 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 0 |
| White | 17 |
| More than one race | 2 |
| Unknown or Not Reported | 2 |
| Primary Tumor Site(Participants) | TMZ 85 mg/m2 mg Orally |
|---|---|
| Count of participants | 23 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Sep 2018 to primary completion in Jun 2023, 57 months.
Results were first posted in Jul 2026, 3 years 1 month after primary completion.
Of 47 phase 2 interventional studies under Gastrointestinal Stromal Tumors, half reached primary completion within 62 months of starting (the median), counting those still running; a quarter within 38 and three quarters within 92. This study's 57 months is close to that.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Temozolomide
Gastrointestinal Stromal Tumors →