Sidewinder Therapeutics closed an oversubscribed $137 million Series B financing round co-led by Frazier Life Sciences and Novartis Venture Fund1
The company has raised a total of $162 million including previous funding from OrbiMed as Series A investor and new investors including Goldman Sachs Alternatives, DCVC Bio, Samsara BioCapital, Longwood Fund, Astellas Venture Management, and Alexandria Venture Investments1
Sidewinder develops next-generation bispecific ADCs designed to target receptor co-complexes on solid tumors, enhancing both tumor cell specificity and internalization1
The company's programs target oncology indications with limited treatment options including squamous cell carcinomas in lung and head and neck cancers, as well as gastrointestinal cancers including colorectal cancer1
Sidewinder expects to advance its lead program into clinical development in 20271
In January 2026, the company partnered with Lonza's Synaffix through a multi-target licensing agreement to apply site-specific linker-payload platform technologies across multiple programs12
The company was founded in 2023 and is headquartered in San Diego1
Sources:
1. https://www.businesswire.com/news/home/20260408583837/en/Sidewinder-Therapeutics-Announces-$137-Million-Series-B-Financing-to-Advance-Precision-Bispecific-ADCs-into-Clinical-Development-for-Cancer
2. https://briefglance.com/articles/lonza-and-sidewinder-bet-on-bispecific-adcs-for-solid-tumors