Sift Biosciences Secures $3.7M in Pre-Seed Funding for Peptide-Based Immunotherapy Platform

Some tumors whisper. They hide. They convince the immune system that nothing is wrong. And in oncology, silence is expensive. Sift Biosciences just stepped into that quiet with $3.7M in oversubscribed Pre-Seed financing, and the signal is loud. Founded in 2024 as a UC Berkeley spin-out, headquartered in San Carlos, this preclinical immunotherapy company is building what it calls T-cell booster peptides. Not another me too molecule. Not incremental chemistry. A platform that aims to wake up immune memory and aim it directly at cancers that have mastered invisibility.

Yue Clare Lou, Ph.D., Co-Founder and CEO, is not guessing. With a Ph.D. in microbiology from UC Berkeley and deep roots in microbial genomics and immune interaction, Yue Clare Lou understands how the immune system remembers. The platform integrates artificial intelligence, metagenomics, and high-throughput immune profiling to identify peptides that can engage pre-existing memory T cells. In plain terms, Sift is sifting through biological noise to find the signals that matter. When you are dealing with microsatellite-stable colorectal and ovarian cancers, the ones labeled immunologically cold, signal is everything.

Freeflow Ventures and Lifespan Vision Ventures co-led the round. Valuence Ventures, Eisai Innovation, Inc., and SBI US Gateway Fund joined the syndicate. Smart capital does not chase hype in preclinical oncology. It backs platforms with a thesis and a team that can execute. An oversubscribed round at this stage says the room believes the math, the science, and the discipline line up.

The proceeds are targeted with intent. In vivo efficacy studies for lead peptide candidates. Expansion of the AI-powered discovery engine. Selection of oncology leads that can move the pipeline forward. No vanity milestones. Just proof that the immune system can be coached, not coerced.

The real lesson here is about leverage. Sift Biosciences is not trying to outspend Big Pharma. It is using computational biology and high-throughput immune profiling to compress time, reduce guesswork, and surface candidates with a higher probability of clinical relevance. When you combine artificial intelligence with real biological depth, you are not automating discovery. You are amplifying judgment.

Immunologically cold tumors have been a graveyard for optimism. If Sift can turn even a fraction of that frost into fire, the oncology landscape shifts. For partners, investors, and future collaborators watching the immune frontier, this is one of those early chapters you read closely. Because sometimes the companies that change outcomes start by listening carefully to what the immune system has been trying to say all along.