Theseus Pharmaceuticals, Inc.

Based in New York, US, and founded in 2017, Theseus Pharmaceuticals, Inc. , is a biotechnology company designed to develop pan-variant kinase inhibitors. Victor Rivera, David Dalgarno, Wei-Sheng Huang, and William Shakesphere are the co-founders, and Tim Clackson is the President and CEO of the company as of 2021. In April 2021, Theseus Pharmaceuticals, Inc.

raised USD 100 million in series B funding from investors including Foresite Capital, Adage Capital Management, Boxer Capital, Farallon Capital Management, Longitude Capital, and more. In October 2021, the firm became a publicly listed company on the Nasdaq under the ticker symbol THRX. In December 2023, Theseus Pharmaceuticals, Inc. , a portfolio company of Adage Capital Management, Farallon Capital Management, Foresite Capital, OrbiMed Advisors, Nextech, Omega Funds, Pontifax Venture Capital, Rock Springs Capital and T Rowe Price  agreed to merge into Concentra, Inc.

, a portfolio company of Cressey & Company, Welsh, Carson, Anderson & Stowe, Select Medical Corporation. The company focuses on the research and development of medicines designed to predict and block treatment-resistant cancer mutations, as well as the treatment of refractory GIST, helping the healthcare industry to address cancer resistance concerns. THE-630, a next-generation pan-variant KIT inhibitor under research by Theseus Pharmaceuticals for the treatment of refractory GIST, is a next-generation pan-variant KIT inhibitor in development. Theseus' pipeline also provides a targeted EGFR inhibitor to treat patients with non-small cell lung cancer who have C797S-mediated resistance to osimertinib in the first or second line.

Theseus is developing tyrosine kinase inhibitors (TKIs) for targeted therapies that address all major drug resistance mutations and a fourth-generation, selective epidermal growth factor receptor (EGFR) inhibitor for C797S-mediated resistance to first- or second-line osimertinib treatment in patients with non-small cell lung cancer (NSCLC).