A Study of HRS-6208 in Combination With HRS-8080, or Fulvestrant, or Letrozole, With or Without HRS-6209 in Patients With Advanced Unresectable or Metastatic Breast Cancer

NCT07389733 | Not Yet Recruiting Phase 1

• 1 other identifier: HRS-6208-201-BC
• Study Type: interventional
• Target: 180
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to evaluate the safety, tolerability, efficacy and pharmacokinetics of HRS-6208 in combination with HRS-8080 ± HRS-6209, or in combination with fulvestrant ± HRS-6209, or in combination with letrozole ± HRS-6209 in patients with advanced unresectable or metastatic breast cancer.

Conditions

Advanced Unresectable or Metastatic Breast Cancer of Adults

Outcome Measures

Primary Outcomes (4)

• Dose-limiting toxicity (DLT)

  The DLT will be evaluated for the last participant in each dose group 28 days after the first dose.

• Recommended phase II dose (RP2D)

  The evaluation of RP2D will be completed approximately one year later than DLT evaluation.

• Incidence and severity of adverse events (AEs)

  Each individual participant will be followed for approximately 8 months, and the entire study process will last for approximately 36 months.

• Objective response rate (ORR)

  For a single subject, the duration will be approximately 8 months, while the entire research process will last for 36 months.

Secondary Outcomes (8)

• Disease control rate (DCR)

  The duration for a single subject will be approximately 8 months, and the entire research process will last for 36 months.

• Duration of response (DoR)

  The duration for a single subject will be approximately 8 months, and the entire research process will last for 36 months.

• Progression-free survival (PFS)

  The duration for a single subject will be approximately 8 months, and the entire research process will last for 36 months.

• Overall survival (OS)

  The duration for a single subject will be approximately 8 months, and the entire research process will last for 36 months.

• The blood drug concentration of HRS-6208

  The duration for a single subject will be approximately 8 months, and the entire research process will last for 36 months.

Study Arms (3)

Arm A: HRS-6208 + HRS-8080 ± HRS-6209

EXPERIMENTAL

HRS-6208 + HRS-8080 ± HRS-6209.

Drug: HRS-6208 Capsule; Drug: HRS-6209 Capsule; Drug: HRS-8080 Tablet

Arm B: HRS-6208 + Fulvestrant ± HRS-6209

EXPERIMENTAL

HRS-6208 + Fulvestrant ± HRS-6209.

Drug: HRS-6208 Capsule; Drug: HRS-6209 Capsule; Drug: Fulvestrant injection

Arm C: HRS-6208 + Letrozole ± HRS-6209

EXPERIMENTAL

HRS-6208 + Letrozole ± HRS-6209.

Drug: HRS-6208 Capsule; Drug: HRS-6209 Capsule; Drug: Letrozole tablets

Interventions

Fulvestrant injection DRUG

Fulvestrant injection.

Arm B: HRS-6208 + Fulvestrant ± HRS-6209

Letrozole tablets DRUG

Letrozole tablets.

Arm C: HRS-6208 + Letrozole ± HRS-6209

HRS-6208 Capsule DRUG

HRS-6208 capsule.

Arm A: HRS-6208 + HRS-8080 ± HRS-6209; Arm B: HRS-6208 + Fulvestrant ± HRS-6209; Arm C: HRS-6208 + Letrozole ± HRS-6209

HRS-6209 Capsule DRUG

HRS-6209 capsule.

Arm A: HRS-6208 + HRS-8080 ± HRS-6209; Arm B: HRS-6208 + Fulvestrant ± HRS-6209; Arm C: HRS-6208 + Letrozole ± HRS-6209

HRS-8080 Tablet DRUG

HRS-8080 tablet.

Arm A: HRS-6208 + HRS-8080 ± HRS-6209

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Female, aged 18-75 (inclusive);
• ECOG score 0-1;
• Estimated survival time ≥ 12 weeks;
• Possessing adequate bone marrow and organ function;
• Participants of reproductive/childbearing potential must agree to take adequate and effective contraceptive measures from the time they sign the informed consent form, during the study treatment period, and up to 2 years after the last use of the trial medication;
• Participants must provide informed consent for this study before the trial and voluntarily sign a written informed consent form.

You may not qualify if:

• Within 5 years prior to the first dose of study medication, the occurrence of other malignancies, except for fully treated cervical carcinoma in situ, basal cell or squamous cell skin cancer, and post-radical surgery thyroid papillary carcinoma;
• Active brain metastasis, carcinomatous meningitis, spinal cord compression, or history of primary central nervous system tumors;
• Severe bone damage caused by tumor bone metastasis as determined by the investigator;
• Adverse events caused by previous anti-tumor treatment have not been resolved;
• Participants with one of multiple factors affecting oral medication;
• History of severe cardiovascular and cerebrovascular diseases;
• Presence of severe infections;
• Significant clinically meaningful bleeding within 3 months prior to the first dose of study medication;
• Active autoimmune diseases, history of immune deficiency, history of autoimmune diseases, or history of diseases or syndromes requiring systemic steroid hormone or immunosuppressive drug treatment, or acquired conditions (HIV infection), congenital immune deficiency diseases, or history of organ transplantation;
• Active untreated hepatitis;
• History of active tuberculosis infection within 1 year prior to enrollment, or history of active tuberculosis infection more than 1 year ago without standard treatment;
• Washout period of prior drug or treatment did not meet protocol requirements before the first dose of study medication;
• Prior use of prohibited drugs specified in the protocol;
• Is pregnant or breastfeeding or planning to become pregnant within 2 years after the last dose of study medication;
• History of clear neurological or psychiatric disorders, and participants with a history of psychiatric drug abuse or drug addiction;

Sponsors & Collaborators

• Shandong Suncadia Medicine Co., Ltd.: lead

Study Sites (1)

West China Hospital, Sichuan University

Chengdu, Sichuan, 610044, China

Location

MeSH Terms

Interventions

Fulvestrant; Letrozole

Intervention Hierarchy (Ancestors)

Estradiol; Estrenes; Estranes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Estradiol Congeners; Gonadal Steroid Hormones; Gonadal Hormones; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Nitriles; Organic Chemicals; Triazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Central Study Contacts

Yunxia Feng

CONTACT

+86-0518-82342973; yunxia.feng.yf29@hengrui.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: An open label, multicenter, phase Ib/II study.

Study Record Dates

• First Submitted: January 29, 2026
• First Posted: February 5, 2026
• Study Start: February 1, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2028
• Last Updated: March 2, 2026

Record last verified: 2026-02

Locations

CN (1)