OPEVESOSTAT TOSILATE for Breast cancer | Ovarian cancer | Endometrial cancer

Inclusion criteria

• {"criterion_text":"- (Cohort A) Has a diagnosis of hormone receptor positive/Human Epidermal Growth Factor Receptor 2 negative invasive breast carcinoma that is either locally advanced disease not amenable to resection with curative intent (herein called unresectable) or metastatic disease not treatable with curative intent.\n- Participants with a history of Hepatitis C virus (HCV) infection are eligible if HCV viral load is undetectable.\n- (Cohort A) Has experienced disease progression on or after at least 1 prior endocrine-based therapy in the metastatic setting.\n- (Cohort B) Has histologically confirmed high-grade epithelial (including high-grade serous or predominantly serous, high-grade endometrioid, malignant mixed Müllerian tumors [carcinosarcoma], or clear cell) ovarian, fallopian tube, or primary peritoneal carcinoma.\n- (Cohort B) Has received between 4 to 8 cycles of platinum-based doublet chemotherapy in third-line setting for ovarian cancer.\n- (Cohort C) Histologically confirmed diagnosis of primary advanced or recurrent low-grade endometrioid carcinoma (eg, Federation of Gynecology and Obstetrics [FIGO] Grade 1/2, or well/moderately differentiated).\n- (Cohort C) Treatment naïve or has received up to 1 prior line of platinum-based therapy in either the advanced/metastatic OR adjuvant/neoadjuvant setting.\n- Participants who have AEs due to previous anticancer therapies must have recovered to ≤Grade 1 or baseline.\n- Human immunodeficiency virus (HIV)-infected participants must have well controlled HIV on antiretroviral therapy.\n- Participants who are Hepatitis B surface antigen positive are eligible if they have received Hepatitis B virus (HBV) antiviral therapy for at least 4 weeks, and have undetectable HBV viral load."}

Exclusion criteria

• {"criterion_text":"- (Cohort A) Breast cancer amenable to treatment with curative intent.\n- Has any prior history or current condition of adrenal insufficiency.\n- HIV-infected participants with a history of Kaposi’s sarcoma and/or Multicentric Castleman’s Disease.\n- Has received a live or live-attenuated vaccine within 30 days before the first dose of study intervention. Administration of killed vaccines is allowed.\n- Has a known additional malignancy that is progressing or has required active treatment within the past 3 years.\n- Has known active central nervous system metastases and/or carcinomatous meningitis.\n- Has a history of stem cell/solid organ transplant.\n- Has not adequately recovered from major surgery or has ongoing surgical complications.\n- (Cohort A) Has advanced/metastatic, symptomatic visceral spread at risk of rapidly evolving into life-threatening complications, such as lymphangitic lung metastases, radiographic evidence of intratumoral cavitation or invasion/infiltration of a major blood vessel, bone marrow replacement, carcinomatous meningitis, significant symptomatic liver metastases, symptomatic pericardial effusion, symptomatic peritoneal carcinomatosis, or the need to achieve rapid symptom control.\n- (Cohort B) Has nonepithelial cancers (germ cell tumors and sex cord-stromal tumors), borderline tumors (low malignant potential), mucinous, seromucinous that is predominantly mucinous, malignant Brenner’s tumor, low-grade serous, low-grade endometrioid, and undifferentiated carcinoma.\n- (Cohort B)Has platinum-resistant ovarian cancer (defined as disease that has progressed per radiographic imaging within 180 days after the last dose of first-line [1L] platinum-based therapy) or platinum-refractory ovarian cancer (defined as disease that has progressed per radiographic imaging while receiving or within 28 days of the last dose of 1L platinum based therapy).\n- (Cohort B) Is a candidate for curative-intent surgery or curative-intent radiotherapy for ovarian cancer.\n- (Cohort C) Has high-grade (FIGO Grade 3 or poorly differentiated) endometroid carcinoma and nonendometrioid histologies of any type (including serous, clear cell, mixed, carcinosarcoma), and neuroendocrine tumors are not eligible. Uterine mesenchymal tumors such as an endometrial stromal sarcoma, leiomyosarcoma, or other types of pure sarcomas, and adenosarcomas are not eligible.\n- (Cohort C) Is a candidate for curative-intent surgery or curative-intent radiotherapy.\n- Has confirmed or suspected adrenal metastases.\n- Has known difficulty in tolerating oral medications, unable to swallow orally administered medication, or conditions which would impair absorption of oral medications."}

Primary endpoints

• {"endpoint_text":"- Progression Free Survival (PFS) – All Cohorts","definition_or_measurement_approach":"Per Response Evaluation Criteria In Solid Tumors Version 1.1 (RECIST 1.1) as assessed by blinded independent central review (BICR)."}

Secondary endpoints

• {"endpoint_text":"- Overall Survival (OS) – All Cohorts","definition_or_measurement_approach":"Overall survival measured as time from randomization/enrollment to death from any cause (definition explicitness: not further detailed in provided data)."}
• {"endpoint_text":"- Clinical Benefit Rate (CBR) – Cohort A","definition_or_measurement_approach":"Per RECIST 1.1 as assessed by blinded independent central review (BICR) (as stated for CBR in objectives)."}
• {"endpoint_text":"- Objective Response Rate (ORR) – All Cohorts","definition_or_measurement_approach":"Per RECIST 1.1 as assessed by blinded independent central review (BICR)."}
• {"endpoint_text":"- Duration of Response (DOR) – All Cohorts","definition_or_measurement_approach":"Per RECIST 1.1 as assessed by blinded independent central review (BICR)."}
• {"endpoint_text":"- Number of Participants who Experience One or More Adverse Events (AEs) – All Cohorts","definition_or_measurement_approach":"Count of participants experiencing one or more AEs (safety/tolerability assessment); detailed AE definitions/methods not provided in the available data."}
• {"endpoint_text":"- Number of Participants who Discontinue Study Intervention Due to an AE – All Cohorts","definition_or_measurement_approach":"Count of participants discontinuing study intervention due to adverse events; detailed rules not provided in the available data."}

Spain

Earliest CTIS Part Ii Submission Date

24-07-2025

Latest Decision Or Authorization Date

14-10-2025

Processing Time Days

82

Number Of Sites

5

Number Of Participants

22

Primary sponsor

Full Name

Merck Sharp & Dohme LLC

Organisation Type

Pharmaceutical company

Country Of Registered Address

United States

Third parties

• {"country":"United States","full_name":"Labcorp Central Laboratory Services LP","duties_or_roles":"sponsorDuties codes: [4]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"Almac Clinical Technologies LLC","duties_or_roles":"sponsorDuties codes: [3]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"Hematogenix Laboratory Services LLC","duties_or_roles":"sponsorDuties codes: [4]","organisation_type":"Laboratory/Research/Testing facility"}
• {"country":"United Kingdom (Northern Ireland)","full_name":"Almac Pharma Services Limited","duties_or_roles":"sponsorDuties codes: [3]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"Almac Diagnostic Services LLC","duties_or_roles":"sponsorDuties codes: [4]","organisation_type":"Pharmaceutical company"}
• {"country":"United States","full_name":"Guardant Health Inc.","duties_or_roles":"sponsorDuties codes: [4]","organisation_type":"Laboratory/Research/Testing facility"}
• {"country":"United States","full_name":"Neogenomics Laboratories Inc.","duties_or_roles":"sponsorDuties codes: [4]","organisation_type":"Laboratory/Research/Testing facility"}
• {"country":"United States","full_name":"Bioclinica Inc.","duties_or_roles":"Imaging Services (sponsorDuties code: 15)","organisation_type":"Laboratory/Research/Testing facility"}