858 Therapeutics Secures $50M Series B Funding

SAN DIEGO—858 Therapeutics has successfully secured $50 million in a Series B funding round. The financing was spearheaded by Avidity Partners and saw contributions from Insight Partners, Mirae Asset Capital, and Alexandria Venture Investments, along with existing backers such as Versant Ventures, NEA, and Logos Capital. With this funding, Monal Mehta, Ph.D., Managing Director at Avidity Partners, will be appointed to the company's Board of Directors.

Jeffrey Stafford, Ph.D., CEO of 858 Therapeutics, expressed his satisfaction with the support from prominent life science investors. He emphasized that the Series B financing highlights the progress made by the 858 team, particularly the advancement of their PARG inhibitor, ETX-19477, into clinical trials.

The funds will be utilized to further develop 858 Therapeutics' pipeline of small molecule therapeutics. The company's flagship asset, ETX-19477, is a highly effective and selective inhibitor of the DNA repair protein PARG. This inhibitor is currently undergoing clinical evaluation in patients with advanced solid tumors. The clinical trial data will be crucial for the continued development of ETX-19477 and will help identify the patients who are most likely to benefit from PARG inhibition.

The Phase 1 clinical trial of ETX-19477 is a comprehensive, multi-center, open-label study that includes dose escalation and expansion phases. It aims to assess the safety, tolerability, dosage, pharmacokinetics, pharmacodynamics, and preliminary efficacy of the drug. The dose escalation part of the study is focused on enrolling patients with specific tumor types and genetic alterations that are expected to respond to PARG inhibition. Once an optimal dose for expansion is determined, the company will proceed with tumor- and biomarker-focused Phase 2 cohorts.

Dr. Mehta expressed optimism about the collaboration, highlighting 858 Therapeutics' experienced management team and their success in targeting difficult drug targets. He emphasized the potential to address various unmet medical needs and bring groundbreaking therapies to patients.

Regarding ETX-19477, it is a cutting-edge and potent small molecule inhibitor of PARG, an enzyme crucial for DNA repair. Inhibiting PARG pharmacologically leads to hyperPARylation, resulting in the death of cancer cells experiencing replication stress. Preclinical studies in animal models have demonstrated significant tumor growth inhibition with ETX-19477, correlated with specific genetic biomarkers. The ongoing Phase 1 study is evaluating the drug's efficacy in patients with advanced solid tumors at multiple locations across the United States.

858 Therapeutics is a biotech company that specializes in drug discovery and the development of small molecule therapeutics targeting novel oncology and immunology pathways. Their primary focus areas include DNA damage repair, innate immunity, and RNA epigenetics. Leveraging decades of drug discovery experience, the company is based in San Diego, California, a prominent biotech hub.

For more information on the Phase 1 study or about 858 Therapeutics, interested parties can visit the clinical trials website or the company's official webpage.