Sift Biosciences closes $3.7 million pre-seed financing for T-cell booster platform
Sift Biosciences closed an oversubscribed $3.7 million pre-seed round to advance a peptide immunotherapy platform designed to activate pre-existing memory T cells. The financing will fund in vivo studies, expansion of its AI-powered discovery engine, and oncology lead selection.
Sift Biosciences has closed an oversubscribed $3.7 million pre-seed financing 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. Proceeds will support in vivo efficacy studies, expansion of the company’s AI-powered peptide discovery engine, and lead candidate selection for its oncology pipeline.
Founded in 2024 as a UC Berkeley spinout, Sift is building a new class of peptide-based immunotherapies designed to engage pre-existing memory T cells to overcome the lack of immunogenicity that limits current cancer immunotherapies. Its platform integrates AI, metagenomics, and high-throughput immune profiling to identify microbial analogs of tumor-associated epitopes, enabling rapid activation of highly responsive memory T-cell populations 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 patients have few effective treatment options. Early preclinical studies support the potential for faster, more potent, and more durable immune responses than existing approaches.
In parallel with oncology, Sift is exploring applications in autoimmune disease, where its platform may enable selective expansion of regulatory T cells to restore immune tolerance. As part of the financing, representatives from Lifespan Vision Ventures and Freeflow Ventures will join Sift’s board of directors.
Sift describes itself as a preclinical immunotherapy company developing “T-cell booster” peptides designed to amplify immune responses in cancers and other immune diseases where current therapies fail. The company said its initial focus is on gastrointestinal and gynecologic cancers, with an expanding pipeline in autoimmunity.