Eli Lilly and Company
Study STX-478-101 (LY4064809) is a multipart, open-label, phase 1/2 study evaluating the safety, tolerability, pharmacokinetics (PK), and preliminary antitumor activity of STX-478 (LY4064809) in participants with advanced solid tumors with P13Ka mutations. Part 1 will evaluate STX-478 as monotherapy in participants with advanced solid tumors. Part 2 will evaluate STX-478 therapy as combination therapy with fulvestrant in participants with hormone receptor positive (HR+) breast cancer. Part 3 will evaluate STX-478 as combination therapy with endocrine therapy (aromatase inhibitors, fulvestrant, tamoxifen, or imlunestrant) and a CDK4/6 Inhibitor (either Ribociclib, Palbociclib or Abemaciclib) in participants with HR+ breast cancer. Each study part will include a 28-day screening period, followed by treatment with STX-478 monotherapy or combination therapy.
Key Inclusion Criteria: * Has an advanced or refractory solid tumor malignancy that is metastatic or locally advanced and unresectable (as specified by Cohort) * Has a new or recent tumor biopsy (collected at screening, if feasible) or will provide an adequate tissue sample prior to screening * Has a tumor that harbors a documented PI3Kα mutation (cohort specific criterion for cohort-specific mutation types) * Is ≥18 years of age at the time of signing the ICF * Has an ECOG performance status score of 0 or 1 at screening * Has adequate organ function as defined per protocol Key Exclusion Cri…
STX-478 is a mutant-selective PI3Kα inhibitor
Fulvestrant
Ribociclib
Palbociclib
Letrozole
Anastrozole
Exemestane
Tamoxifen
Abemaciclib
Imlunestrant
Metformin