An Investigational Study of BG-75202 Alone and in Combination With Other Therapeutic Agents in Adults With Advanced Solid Tumors

A Phase 1a/1b Study Evaluating the Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Preliminary Antitumor Activity of BG-75202, Alone and in Combination With Other Agents in Patients With Advanced Solid Tumors

The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics, and preliminary antitumor activity of BG-75202 (KAT6A/B inhibitor) alone and in combination with other therapies in participants with breast cancer and other advanced solid tumors.

Study Overview

• Status: Recruiting
• Conditions: Breast Cancer; Advanced Solid Tumor
• Intervention / Treatment: Drug: BG-75202; Drug: Estrogen Receptor Antagonist; Drug: CDK4 Inhibitor; Drug: Aromatase Inhibitor

• Study Type: Interventional
• Enrollment (Estimated): 86
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Study Director; Phone Number: 877-828-5568; Email: clinicaltrials@beonemed.com

Study Locations

• Australia
  • New South Wales
    • Blacktown, New South Wales, Australia, NSW 2148
      • Recruiting
      • Blacktown Cancer and Haematology Centre
    • Camperdown, New South Wales, Australia, NSW 2050
      • Recruiting
      • Chris OBrien Lifehouse
  • South Australia
    • Adelaide, South Australia, Australia, SA 5000
      • Recruiting
      • Cancer Research South Australia
  • Victoria
    • Melbourne, Victoria, Australia, VIC 3000
      • Recruiting
      • Peter MacCallum Cancer Centre
• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100142
      • Recruiting
      • Beijing Cancer Hospital
    • Beijing, Beijing Municipality, China, 100021
      • Recruiting
      • Cancer Hospital Chinese Academy of Medical Sciences
  • Guangdong
    • Guangzhou, Guangdong, China, 510555
      • Recruiting
      • Sun Yat Sen University Cancer Center Huangpu Branch
  • Heilongjiang
    • Harbin, Heilongjiang, China, 150000
      • Recruiting
      • Harbin Medical University Cancer Hospital
  • Jiangsu
    • Nanjing, Jiangsu, China, 210036
      • Recruiting
      • Jiangsu Province Hospital Longjiang Branch
  • Shanghai Municipality
    • Shanghai, Shanghai Municipality, China, 201321
      • Recruiting
      • Fudan University Shanghai Cancer Centerpudong
  • Tianjin Municipality
    • Tianjin, Tianjin Municipality, China, 300060
      • Recruiting
      • Tianjin Medical University Cancer Institute and Hospital
• Italy
  • Milan, Italy, 20141
    • Recruiting
    • Istituto Europeo di Oncologia
  • Naples, Italy, 80131
    • Recruiting
    • Istituto Nazionale Tumori Fondazione G Pascale
  • Roma, Italy, 00168
    • Recruiting
    • Fondazione Policlinico Universitario Agostino Gemelli
  • Rozzano, Italy, 20089
    • Recruiting
    • Istituto Clinico Humanitas
• Spain
  • Barcelona, Spain, 08035
    • Recruiting
    • Hospital Universitario Vall Dhebron
  • Barcelona, Spain, 8023
    • Recruiting
    • Next Oncology Barcelona
  • Madrid, Spain, 28041
    • Recruiting
    • Hospital Universitario 12 de Octubre
  • Madrid, Spain, 28240
    • Recruiting
    • Hospital Clinico San Carlos
  • Málaga, Spain, 29010
    • Recruiting
    • Hospital Universitario Virgen de la Victoria
• United States
  • Alabama
    • Birmingham, Alabama, United States, 35294-0004
      • Recruiting
      • University of Alabama at Birmingham Hospital
  • Connecticut
    • New Haven, Connecticut, United States, 06510
      • Recruiting
      • Yale Cancer Center
  • Missouri
    • St Louis, Missouri, United States, 63110-1010
      • Recruiting
      • Washington University in St Louis
  • Texas
    • Austin, Texas, United States, 78758
      • Recruiting
      • Next Oncology Austin
    • Houston, Texas, United States, 77030-4009
      • Recruiting
      • The University of Texas Md Anderson Cancer Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Part 1A: Participants with histologically or cytologically confirmed advanced, metastatic breast cancer and other solid tumors who have exhausted, are intolerant of all available standard of care therapies, and/or without available standard of care therapies.
• Part 1B and Part 2A: Participants with advanced breast cancer with 1 to 3 prior lines of systemic therapy in the metastatic setting. Prior lines in the advanced/ metastatic setting may not exceed 2 lines of chemotherapy (inclusive of antibody-drug conjugate with cytotoxic payload).
• Parts 2B and 2C: Participants with advanced breast cancer enrolled in regions where cyclin-dependent kinase 4/6 (CDK4/6) inhibitors are not approved and/or not available as the first-line treatment and who are CDK4/6 inhibitor treatment naïve and did not receive any previous systemic treatment for advanced disease.
• Participants with breast cancer must have histologically or cytologically confirmed advanced breast cancer at the time of most recent testing, based on American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guidelines.
• Female participants with metastatic breast cancer must be postmenopausal or receiving ovarian function suppression treatment.
• Measurable disease as assessed by Response Evaluation Criteria in Solid Tumors (RECIST) v 1.1.
• Stable Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1.
• Adequate organ function.

Exclusion Criteria:

• Prior exposure to KAT6A/B or KAT7 inhibitors/degraders.
• Patients with active leptomeningeal disease or uncontrolled, untreated brain metastasis.
• Participants with any malignancy ≤ 3 years before screening for the study except for the specific cancer under investigation in this study and any locally recurring cancer that has been treated curatively which in the opinion of the investigator is unlikely to require intervention during the study.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part 1A: Dose Escalation and Safety Expansion, BG-75202 Monotherapy; Sequential cohorts of increasing dose levels of BG-75202 will be evaluated as monotherapy.	Drug: BG-75202; Administered orally.
Experimental: Part 1B: Dose Escalation and Safety Expansion, BG-75202 + Estrogen Receptor Antagonist; Sequential cohorts of increasing dose levels of BG-75202 will be evaluated in combination with an estrogen receptor antagonist.	Drug: BG-75202; Administered orally.; Drug: Estrogen Receptor Antagonist; Administered by intramuscular injection.
Experimental: Part 2A: Dose Optimization, BG-75202 + Estrogen Receptor Antagonist; Participants will receive BG-75202 in combination with an estrogen receptor antagonist.	Drug: BG-75202; Administered orally.; Drug: Estrogen Receptor Antagonist; Administered by intramuscular injection.
Experimental: Part 2B: Safety Run-In, BG-75202 + CDK4 inhibitor + Aromatase Inhibitor; Participants will receive BG-75202 in combination with a cyclin-dependent kinase 4 (CDK4) inhibitor and an aromatase inhibitor.	Drug: BG-75202; Administered orally.; Drug: CDK4 Inhibitor; Administered orally.; Drug: Aromatase Inhibitor; Administered orally.
Experimental: Part 2C: Dose Expansion, BG-75202 + CDK4 inhibitor + Aromatase Inhibitor; Participants will receive BG-75202 in combination with a CDK4 inhibitor and an aromatase inhibitor.	Drug: BG-75202; Administered orally.; Drug: CDK4 Inhibitor; Administered orally.; Drug: Aromatase Inhibitor; Administered orally.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 1: Number of Participants with Adverse Events (AEs)	Number of participants with treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs), including physical examination findings, electrocardiogram results, laboratory values, and AEs meeting protocol-defined dose-limiting toxicity (DLT) criteria.	From first dose to 30 days after last dose or initiation of a new anticancer therapy, whichever occurs first, up to approximately 12 months
Part 1: Recommended Dose for Expansion (RDFE)	The RDFE is based on the maximum tolerated dose (MTD) or maximum administered dose (MAD) with consideration of the tolerability, pharmacokinetics (PK), pharmacodynamics, antitumor activity, and any other available relevant data.	Estimated approximately 1 year
Part 2: Overall Response Rate (ORR)	ORR is defined as the percentage of participants with partial or complete response, as assessed by the investigator using Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1).	Up to approximately 2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Part 1: ORR	ORR is defined as the percentage of participants with partial response (PR) or complete response (CR), as assessed by the investigator using RECIST v1.1.	Up to approximately 1 year
Part 1: Duration of Response (DOR)	DOR is defined as the time from the first determination of an objective response to disease progression documented after treatment initiation or death, whichever occurs first.	Up to approximately 1 year
Part 1: Time to Response (TTR)	TTR is defined as the time from treatment initiation to the first determination of objective response.	Up to approximately 1 year
Part 2: DOR	DOR is defined as the time from the first determination of an objective response to disease progression documented after treatment initiation or death, whichever occurs first.	Up to approximately 2 years
Part 2: TTR	TTR is defined as the time from treatment initiation to the first determination of objective response.	Up to approximately 2 years
Part 2: Disease Control Rate (DCR)	DCR is defined as the percentage of participants who achieve CR, PR, or stable disease as assessed by investigator's review.	Up to approximately 2 years
Part 2: Clinical Benefit Rate (CBR)	CBR is defined as the percentage of participants who achieve CR, PR, or durable stable disease (stable disease ≥ 24 weeks).	Up to approximately 2 years
Part 2: Progression-Free Survival (PFS)	PFS is defined as the time from the date of the first dose of study treatment(s) to the date of the first documentation of disease progression assessed by investigator's review or death, whichever occurs first.	Up to approximately 2 years
Part 2: Number of Participants with Adverse Events (AEs)	Number of participants with treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs), including physical examination findings, electrocardiogram results, and laboratory values.	Up to approximately 2 years
Part 2: Recommended Phase 2 Dose (RP2D)	The RP2D of BG-75202 will take into consideration the totality of data including, but not limited to, PK, pharmacodynamics, safety, tolerability, and antitumor activity.	Up to approximately 2 years
Parts 1 and 2: Maximum Observed Plasma Concentration (Cmax) of BG-75202		Up to approximately 4 months
Parts 1 and 2: Minimum Observed Plasma Concentration (Ctrough) of BG-75202		Up to approximately 4 months
Parts 1 and 2: Area Under the Plasma Concentration-Time Curve (AUC) of BG-75202		Up to approximately 4 months
Parts 1 and 2: Terminal Half-Life (t1/2) of BG-75202		Up to approximately 4 months

Collaborators and Investigators

• Sponsor: BeOne Medicines
• Investigators: Study Director: Study Director, BeOne Medicines

Study record dates

Study Major Dates

• Study Start (Actual): December 11, 2025
• Primary Completion (Estimated): September 30, 2029
• Study Completion (Estimated): January 13, 2037

Study Registration Dates

• First Submitted: October 28, 2025
• First Submitted That Met QC Criteria: October 28, 2025
• First Posted (Actual): October 29, 2025

Study Record Updates

• Last Update Posted (Actual): May 11, 2026
• Last Update Submitted That Met QC Criteria: May 8, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: KAT6 inhibitor
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Skin Diseases; Breast Diseases; Skin and Connective Tissue Diseases; Breast Neoplasms; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Hormones, Hormone Substitutes, and Hormone Antagonists; Enzyme Inhibitors; Steroid Synthesis Inhibitors; Hormone Antagonists; Estrogen Antagonists; Peptides; Amino Acids, Peptides, and Proteins; Proteins; Pharmacologic Actions; Chemical Actions and Uses; Intracellular Signaling Peptides and Proteins; Cell Cycle Proteins; Tumor Suppressor Proteins; Neoplasm Proteins; Cyclin-Dependent Kinase Inhibitor Proteins; Aromatase Inhibitors; Cyclin-Dependent Kinase Inhibitor p16; Estrogen Receptor Antagonists
• Other Study ID Numbers: BG-75202-101; 2025-523553-34-00 (Ctis)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

IPD Plan Description

BeOne shares data on completed studies responsibly and provides qualified scientific and medical researchers access to data and supporting documentation for clinical trials in dossiers for medicines and indications after submission and approval in the United States, China, and Europe. Clinical trials supporting subsequent local approvals, new indications, or combination products are eligible for sharing once corresponding regulatory approvals are achieved.

BeOne shares data only when permitted by applicable data privacy and security laws and regulations, when it is feasible to do so without compromising the privacy of study participants, and other considerations.

Qualified researchers with appropriate competencies who are engaged in novel scientific research may submit a request for participant-level data with a research proposal for BeOne review. Research teams must include a biostatistician and sign a Data Sharing Agreement prior to receiving access to clinical trial data.

• IPD Sharing Time Frame: See plan description
• IPD Sharing Access Criteria: See plan description
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No