Prelude Therapeutics stock keeps Lilly-backed PRT13722 trial in focus

Prelude Therapeutics said on October 13, 2026, that it had entered a clinical trial collaboration and supply agreement with Eli Lilly for its oral KAT6A selective degrader PRT13722. The agreement covers combinations with Lilly's abemaciclib and imlunestrant in patients with HR+/HER2- breast cancer, according to the Prelude Therapeutics press release.

The company expects to begin enrollment in the fourth quarter of 2026, starting with monotherapy dose escalation before moving into combination cohorts. The US Food and Drug Administration has cleared the Phase 1 study under Prelude's Investigational New Drug application.

Lilly supply supports combination testing

Lilly will provide the CDK4/6 inhibitor abemaciclib and the oral estrogen receptor antagonist imlunestrant. Prelude retains full global development and commercial rights to PRT13722, leaving the company responsible for the program while adding established combination agents to the trial design.

Prelude's rationale rests on preclinical findings. The company reported activity for PRT13722 as a monotherapy and synergy with endocrine therapies, CDK4/6 inhibitors and PI3K inhibitors across HR+ breast cancer models. Those findings remain laboratory evidence; the upcoming study will test safety, dosing and early activity in humans.

Three programs shape the pipeline

MarketBeat reported on October 22, 2026, that Prelude is prioritizing three clinically validated programs: a JAK2 JH2 inhibitor, the KAT6A degrader for breast cancer and a mutant calreticulin program for myeloproliferative neoplasms. The report said the company expects initial proof-of-concept data from the KAT6A program in the second half of 2027.

Precision oncology specialist

Prelude Therapeutics is a clinical-stage precision oncology company based in Wilmington, Delaware. It uses cancer biology and medicinal chemistry to develop small-molecule inhibitors and degraders for molecular vulnerabilities in cancer, with programs spanning breast cancer and myeloproliferative neoplasms, as described in the company's science overview. Owler identifies Arvinas, Aragen and Black Diamond as biotechnology competitors. Prelude is the smaller clinical-stage specialist in that comparison, while the named peers have broader operating footprints or greater scale, according to Owler.

US biotechnology shares remain sensitive to clinical data, regulatory decisions and financing expectations; investors can follow the broader S&P 500 market environment.

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