Overview

BGB-43395 Alone or as Part of Combination Therapies in Participants With Breast Cancer and Other Advanced Solid Tumors

Status:
Recruiting
Trial end date:
2026-05-01
Target enrollment:
0
Participant gender:
All
Summary
This is a dose escalation and dose expansion study to compare how well BGB-43395, a cyclin-dependent kinase 4 (CDK4) inhibitor, works as monotherapy or in combination with either fulvestrant or letrozole in participants with hormone receptor positive (HR+) and human epidermal growth factor 2 negative (HER2-) breast cancer (BC) and other advanced solid tumors. The main purpose of this study is to explore the recommended dosing for BGB-43395.
Phase:
Phase 1
Accepts Healthy Volunteers?
No
Details
Lead Sponsor:
BeiGene
Treatments:
Fulvestrant
Letrozole
Criteria
Inclusion Criteria:

- Phase 1a (Dose Escalation): Participants with histologically or cytologically
confirmed advanced, metastatic, or unresectable solid tumors associated with
dependency on CDK4, including HR+ breast cancer, non-small cell lung cancer, and
others.

- Phase 1a: Received prior therapy for their condition (if available) and should be
refractory to or intolerant of standard-of-care therapies. In regions where approved
and available, participants with HR+ breast cancer must have received at least 2 prior
lines of treatment.

- Phase 1b (Dose Expansion): Selected tumor cohorts will include HR+/HER2- breast cancer
and additional tumor types.

- Phase 1b: Participants with HR+/HER2- breast cancer enrolled in regions where CDK4/6
inhibitors are approved and available must have received at least one line of therapy
for advanced disease including endocrine therapy and a CDK4/6 inhibitor. Participants
can have received up to 2 lines of prior cytotoxic chemotherapy for advanced disease.

- Eastern Cooperative Oncology Group (ECOG) Performance Status ≤ 1.

- Female participants with metastatic HR+/HER2- breast cancer must be postmenopausal or
receiving ovarian function suppression treatment.

- Adequate organ function without symptomatic visceral disease.

Exclusion Criteria:

- Prior therapy selectively targeting CDK4 (prior CDK4/6 inhibitor therapy is permitted
and required in local regions where it is approved and available).

- Known leptomeningeal disease or uncontrolled, untreated brain metastasis.

- Any malignancy ≤ 3 years before the first dose of study drug(s) except for the
specific cancer under investigation in this study and any locally recurring cancer
that has been treated with curative intent (eg, resected basal or squamous cell skin
cancer, superficial bladder cancer, or carcinoma in situ of the cervix or breast).

- Uncontrolled diabetes.

- Infection requiring systemic antibacterial, antifungal, or antiviral therapy ≤ 28 days
before the first dose of study drug(s), or symptomatic COVID-19 infection.

- History of hepatitis B or active hepatitis C infection.

- Prior allogeneic stem cell transplantation, or organ transplantation.

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