Most drugs block a bad protein and hope it stays blocked. SEED builds molecular glues that make the cell destroy the protein entirely - reaching targets medicine has never been able to touch.
SEED THERAPEUTICS — the corporate mark set against a rendered E3 ligase-target protein complex, the molecular handshake its drugs are designed to engineer.
For as long as modern pharmacology has existed, a drug's job has been to occupy - to slot into a protein's active site and jam the machinery. That approach works beautifully, except for one inconvenient fact: roughly four out of five human proteins have no pocket to jam. They are flat, slippery, or structurally featureless. The industry has a blunt word for them - undruggable. And a great many of them are precisely the proteins that drive cancer, neurodegeneration and disease.
SEED Therapeutics, a clinical-stage biotech headquartered at 28 Liberty Street in Lower Manhattan, is built around a different verb. Instead of occupying a protein, its molecules glue it to the cell's own disposal system - the ubiquitin-proteasome pathway - and let the cell shred it. These are molecular glue degraders: small molecules that don't need a deep binding pocket, only a surface to grip. That single shift, from blocking to degrading, is what puts the undruggable back on the table.
The company was founded in 2020 out of research that began at the University of Washington, where CEO Lan Huang and her collaborators set their sights on the proteins existing drugs cannot treat. What they assembled since is less a single product and more a discovery engine - and, as of January 2026, a drug in human beings.
Create the glue. Capture the protein. Eliminate disease.
Most targeted-degradation companies build glues around the same two E3 ligases - the "adaptors" that hand a protein to the shredder. SEED's RITE3 platform systematically searches a far larger field to find the best-matched pair for each target.
RITE3 pairs a disease-causing target with the most suitable of 600+ human E3 ligases, then designs a custom small-molecule glue using structure-based design, computational chemistry and chemical biology.
The glue draws target and ligase into a productive complex - a molecular handshake that tags the target for destruction, catalytically, so one molecule can act again and again.
The tagged protein is fed into the proteasome and degraded. The disease driver is removed, not merely muted - opening targets in oncology, neurodegeneration, immunology and virology.
Approximate number of E3 ligases each approach can systematically design against.
Illustrative comparison based on SEED's public platform claims.
A degrader only works if the target and ligase are expressed in the same cells and can be drawn together. Searching a wider set of ligases means more targets become reachable - including tissue-specific and previously intractable ones. That breadth is SEED's core bet.
SEED's lead candidate reached first-in-human dosing in January 2026, anchoring a pipeline that spans four disease areas.
| Program | Target | Area | Stage | Notes |
|---|---|---|---|---|
| ST-01156 | RBM39 degrader | Oncology | Phase 1 | Oral, brain-penetrant. First patient dosed Jan 2026. Ewing sarcoma, KRAS-mutant & hepatocellular cancers. |
| Tau Degrader | Tau protein | Neurodegeneration | Preclinical | Lead-ID stage; targeting Alzheimer's and related tauopathies. |
| Immunology | Undisclosed | Immunology | Discovery | Advanced with strategic partners Eli Lilly and Eisai. |
| +6 programs | Various | Onco / Neuro / Viro | Discovery | Additional RITE3-derived programs; nine total across the portfolio. |
ST-01156 degrades RBM39, a regulator of RNA splicing overexpressed across many cancers. SEED chose one of oncology's hardest, most neglected targets first - Ewing sarcoma, a rare pediatric cancer with no new approved therapy in over 30 years. The drug carries FDA Orphan Drug and Rare Pediatric Disease designations.
SEED advances its proprietary programs on venture equity while generating revenue from research collaborations. Partners including Eli Lilly and Eisai contribute upfront, equity and milestone payments - a structure that funds internal science while validating the platform through big-pharma co-development.
SEED's founding bench reads like a syllabus of protein-degradation science - the people who discovered the pathway, named the modality and solved its first structures.
Solved the first E2-E3 ubiquitin ligase structure (published in Science) and a serial biotech entrepreneur who took BeyondSpring public on NASDAQ.
2004 Nobel Prize in Chemistry for discovering the ubiquitin-proteasome system - the exact cellular machinery SEED's drugs recruit.
Professor of Pharmacology at the University of Washington and HHMI investigator; a pioneer of E3 ligase structures who coined the term "molecular glue."
Chair of Biochemistry & Molecular Pharmacology at NYU School of Medicine and HHMI investigator; a preeminent authority on E3 ligase biology.
SEED's most notable backer, Eli Lilly, has been both a cornerstone investor and a research collaborator since inception - a rarer kind of check.
Targeted protein degradation is one of biotech's hottest arenas, with public peers such as Arvinas, Kymera, Nurix, Monte Rosa, C4 and Plexium. Many concentrate on the same handful of E3 ligases. SEED's differentiation is breadth of ligase reach plus a founding team synonymous with the field's foundational science.
SEED's direct counterparties are large pharmaceutical partners who license and co-develop its programs. The ultimate users are patients with cancers, neurodegenerative, immunologic and viral diseases driven by proteins conventional medicine cannot reach.
Molecular glue degraders for targets beyond reach.
Launched in New York out of University of Washington research, co-founded by Lan Huang, Avram Hershko, Ning Zheng and Michele Pagano.
Featured prominently in a Nature Biotechnology publication on molecular glue development.
Presented dual targeted-protein-degradation programs at AACR 2025 and completed a $30 million Series A-3 financing in September.
Dosed the first patient in the Phase 1 study of oral RBM39 degrader ST-01156 in January, and detailed clinical progress at ASCO in June.