First-in-Human Study of Tersolisib (STX-478) as Monotherapy and in Combination With Other Antineoplastic Agents in Participants With Advanced Solid Tumors

Summary

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.

Shortened from the sponsor's brief summary. View official record on ClinicalTrials.gov

Conditions studied

• Breast Cancer
• Solid Tumors, Adult

Eligibility basics and study details

Study type

Interventional

Phase

Phase 1/2

Ages

18 years and older

Sex

All

Healthy volunteers

Not accepted

Sponsor

Eli Lilly and Company

Last updated on ClinicalTrials.gov

July 7, 2026

These are the basic criteria only. The full inclusion and exclusion criteria are on the official record, and the study team decides who can take part.

US recruiting sites