12 and older, any sex, with Solid Tumor or Leiomyosarcoma. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Changes in Phospho-Chk1 Levels in Biopsy SpecimensPrimary· Baseline, Day 15
Changes in the levels of Phospho-Chk1 in biopsy specimens of patients treated with M6620 monotherapy from baseline to cycle 1 day 15. This is a pharmacodynamic endpoint to evaluate target engagement. Results are in percent change of Phospho-Chk1 levels from baseline versus on-treatment biopsies.
Group
Value
95% CI
Cohort T1: ATRX-mutant Leiomyosarcoma
156
-45 – 511
Cohort T2: Truncating ATM Mutation
196
131 – 272
Cohort T3: Other HR Gene Mutations
89
-36 – 603
Cohort T4: SDH-Mutant GIST
84
84 – 84
Change in yH2AX Levels in Biopsy SpecimensPrimary· Baseline, Day 15
Changes in the levels of yH2AX in biopsy specimens of patients treated with M6620 monotherapy from baseline to cycle 1 day 15.
Group
Value
95% CI
Cohort T1: ATRX-mutant Leiomyosarcoma
-36.8
-83.9 – 820.4
Cohort T2: Truncating ATM Mutation
142.2
-40.5 – 395.9
Cohort T3: Other HR Gene Mutations
-34.3
-50.9 – 114.5
Cohort T4: SDH-Mutant GIST
-30.8
-30.8 – -30.8
Disease Control RatePrimary· 16 weeks
The number of participants that achieve either Stable Disease (SD), Partial Response (PR), or Complete Response (CR) at 16 weeks.
* Complete Response (CR): Disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to \<10 mm.
* Partial Response (PR): At least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters.
* Stable Disease (SD): Neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD, taking as reference the smallest sum diamet
Group
Value
95% CI
Cohort T1: ATRX-mutant Leiomyosarcoma
0
Cohort T2: Truncating ATM Mutation
0
Cohort T3: Other HR Gene Mutations
0
Cohort T4: SDH-Mutant GIST
2
Number of Participants With Treatment Related Serious Adverse EventsSecondary· AE data was collected from cycle 1 day 1 until 30 days after last dose or resolution of the AE.
Adverse events will be assessed using Common Terminology Criteria for Adverse Events (CTCAE 5.0)
Group
Value
95% CI
Cohort T1-T4 (Analyzed Together for AEs)
12
Adverse events — posted to ClinicalTrials.gov
Time frame: AE data was collected from cycle 1 day 1 until 30 days after last dose or resolution of the AE. The study length for collection of AEs was 575 days total..
Reporting threshold: 5%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
NCT03704467 — Phase Ib/II Study of Carboplatin + M6620 + Avelumab in PARPi-resistant Ovarian Cancer
· Phase 1
· completed
NCT03641547 — M6620 Plus Standard Treatment in Oesophageal and Other Cancer
· Phase 1
· completed
NCT02157792 — M6620 First in Human Study
· Phase 1
· completed
Other recruiting trials for Solid Tumor
Currently open trials in the same condition.
NCT07489378 — NCI Childhood Cancer Data Initiative (CCDI) Led Pediatric, Adolescent, and Young Adult Rare Cancer Registry for Very Rar
· recruiting
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· EARLY_PHASE1
· recruiting
NCT07382544 — Phase 1b Trial of BMS-986504 in Combination With Olaparib in Patients With MTAP Loss
· Phase 1
· recruiting
NCT07466160 — A Phase Ib/II Study of 7MW3711 Combined With JS207 in Advanced Solid Tumors
· Phase 1, PHASE2
· recruiting
NCT07450560 — Research on Real-time Proton Therapy Guidance Through Monitoring Proton Range Using All-digital PET
· active not recruiting
Other Massachusetts General Hospital trials
Trials by the same sponsor.
NCT03585946 — Outcomes in Stevens Johnsons Syndrome and Toxic Epidermal Necrolysis
· withdrawn
NCT07214831 — A Feasibility and Acceptability Study of a Large Language Model-based Chatbot for Brief Alcohol Intervention Among Emerg
· NA
· not yet recruiting
NCT06686901 — A Randomized Controlled Trial of a Smartphone Delivered Treatment for Suicidal Thoughts and Behavior
· NA
· not yet recruiting
NCT05854212 — Behavioral Economics to Implement Nutrition Ranking in Food Pantries
· NA
· not yet recruiting
NCT07323446 — The MIND Study: The MGH/MIT Investigation of NAC on Dysregulation
· EARLY_PHASE1
· not yet recruiting
Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Massachusetts General Hospital
Last refreshed: 7 July 2023
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT03718091.