Sift Biosciences has closed an oversubscribed $3.7 million pre-seed financing round to accelerate development of its next-generation peptide immunotherapy platform designed to activate pre-existing memory T cells. The round was co-led by Freeflow Ventures and Lifespan Vision Ventures, with participation from Valuence Ventures, Eisai Innovation, SBI US Gateway Fund, and other early supporters.
Founded in 2024 as a spinout of the University of California, Berkeley, Sift is developing a new class of peptide-based immunotherapies intended to overcome the limited immunogenicity that constrains many current cancer treatments. Its platform integrates artificial intelligence, metagenomics and high-throughput immune profiling to identify microbial analogs of tumor-associated epitopes. This approach is designed to activate infection-trained memory T cells without requiring de novo immune priming.
The company’s initial focus is on immunologically “cold” solid tumors, including microsatellite-stable colorectal and ovarian cancers, where treatment options remain limited. Early preclinical studies indicate the potential for faster, stronger and more durable immune responses compared to existing approaches.
In addition to oncology, Sift is exploring applications in autoimmune diseases, where selective expansion of regulatory T cells could help restore immune tolerance.
Proceeds from the financing will fund in vivo efficacy studies, expansion of the company’s AI-powered peptide discovery engine and advancement of lead candidate selection within its oncology pipeline. As part of the round, Altar Munis, Ph.D., Associate at Lifespan Vision Ventures, and Kevin Barrett, Managing Partner at Freeflow Ventures, will join Sift’s board of directors.
KEY QUOTES:
“Most immunotherapies fail not because the immune system is weak, but because it’s never meaningfully engaged. By harnessing infection-trained memory T cells, we’re developing a platform that can rapidly amplify immune responses in cancers that don’t respond to today’s treatments. This financing enables us to demonstrate in vivo proof-of-concept and advance our lead programs.”
Clare Lou, Ph.D., CEO and Cofounder, Sift Biosciences
“Sift is tackling one of the most fundamental challenges in immuno-oncology with a differentiated and biologically grounded strategy. Since day one, Clare and the team have had a clear vision for building a scalable platform, and we’re excited to support them through this next phase of execution.”
Kevin Barrett, Managing Partner, Freeflow Ventures
“Sift’s approach reflects a shift toward precision immune modulation by leveraging the immune system’s existing memory. The platform’s potential across both cancer and autoimmunity makes it especially compelling.”
Altar Munis, Ph.D., Associate, Lifespan Vision Ventures
