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OncoMatch/Clinical Trials/NCT07174336

A Study of Tersolisib (LY4064809/STX-478) With Other Anti-Cancer Treatments in Participants With Advanced Breast Cancer With a Genetic Change (PIK3CA)

Is NCT07174336 recruiting? Yes, currently enrolling (May 2026). This Phase 3 trial studies multiple treatments for breast neoplasms.

Phase 3RecruitingEli Lilly and CompanyNCT07174336Data as of May 2026

Treatment: LY4064809 · Ribociclib · Palbociclib · Abemaciclib · Anastrozole · Letrozole · Exemestane · FulvestrantThe purpose of the study is to assess the efficacy and safety of the addition of Tersolisib (LY4064809/STX-478) to other anti-cancer drugs as first treatment for advanced hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancer. Participants can remain in the study as long as the drug is helping the cancer without unbearable side effects.

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Extracted eligibility criteria

Cancer type

Breast Carcinoma

Biomarker criteria

Required: PIK3CA activating mutation

Have evidence of an activating PIK3CA mutation, detected in tumor or blood samples using an appropriate assay.

Required: ESR1 overexpression (ER+ (≥1% tumor cells stained positive))

Documented ER+ and/or progesterone receptor-positive (PR+) tumor according to ASCO/CAP Guidelines, defined as greater than or equal to (≥)1 percent (%) of tumor cells stained positive

Required: PR (PGR) overexpression (PR+ (≥1% tumor cells stained positive))

Documented ER+ and/or progesterone receptor-positive (PR+) tumor according to ASCO/CAP Guidelines, defined as greater than or equal to (≥)1 percent (%) of tumor cells stained positive

Required: HER2 (ERBB2) negative (IHC 1+ or 2+ with negative FISH) (IHC 1+ or 2+ with negative FISH)

HER status: immunohistochemistry score of 1+ or score of 2+ with a negative Fluorescence In Situ Hybridization (FISH) based on local results as defined in the ASCO/CAP Guidelines

Prior therapy

Min 0 prior lines

Cannot have received: local or systemic antineoplastic therapy or investigational anticancer agent

Exception: within 14 days or 4 half-lives, whichever is longer, prior to randomization up to a maximum washout period of 28 days

Have received treatment with any local or systemic antineoplastic therapy or investigational anticancer agent within 14 days or 4 half-lives, whichever is longer, prior to randomization up to a maximum washout period of 28 days.

Structured fields extracted by AI. May contain errors — verify against the official protocol.

US trial sites

  • Alaska Oncology and Hematology · Anchorage, Alaska
  • Ironwood Cancer & Research Centers · Chandler, Arizona
  • Mayo Clinic in Arizona - Phoenix · Phoenix, Arizona
  • The University of Arizona Cancer Center - North Campus · Tucson, Arizona
  • Highlands Oncology Group · Springdale, Arkansas

Showing up to 5 US sites. See all sites on ClinicalTrials.gov →

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