Theseus Pharmaceuticals

Theseus Pharmaceuticals was a clinical-stage biopharmaceutical company initially formed on December 29, 2017 and headquartered at 245 Main Street, Cambridge, Massachusetts. The company focused on improving the lives of cancer patients through the discovery, development, and commercialization of transformative medicines, developing pan-variant tyrosine kinase inhibitors (TKIs) designed to overcome treatment-resistant mutations that limit the durability of currently available targeted cancer therapies. Theseus went public on Nasdaq under the ticker THRX. After discontinuing its former lead program in 2023 following dose-limiting toxicities in two patients and exploring strategic alternatives, Theseus agreed in December 2023 to be acquired by Concentra Biosciences for between $3.90 and $4.05 per share in cash plus a contingent value right, a deal valuing the company at roughly $185 million; the tender offer closed in February 2024.