# Cullgen

Source: https://onco.cc/companies/cullgen/  
OnCo record `cullgen` (Company). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Cullgen designs drugs that tag disease-causing proteins for destruction by the cell's own recycling system, and links such drugs to antibodies. In May 2026 it became part of Gyre Therapeutics, a US and China company focused on fibrosis.

## Summary

Cullgen is a San Diego clinical-stage biopharmaceutical company developing targeted protein degraders (TPDs) and degrader-antibody conjugates (DACs) for cancer, pain and inflammatory diseases, positioning DACs as the next generation of antibody-drug conjugates. Its discovery work uses novel E3 ligase ligands beyond cereblon and has operations in both the United States and China. On 2 March 2026 Nasdaq-listed Gyre Therapeutics (GYRE) agreed to acquire Cullgen in an all-stock transaction valued at about 300 million US dollars; the deal closed on 4 May 2026, Cullgen became a wholly owned subsidiary and its chief executive, Ying Luo, became president and chief executive of Gyre. Gyre describes the combined company as a US- and China-based, fully integrated biopharmaceutical company with a fibrosis-first commercial business and a degrader and DAC discovery engine.

## Fields

- Kind: Company
- Last checked: 2026-09-10
- HQ: San Diego, CA
- Type: biotech
- Website: https://www.cullgen.com/

## Notes

- Cullgen's pipeline page returned 404, so individual programme names (for example its TRK degrader) and clinical phases are not recorded. Pre-acquisition venture rounds were not found in SEC Form D searches. Headquarters recorded as San Diego per the company site; the group has substantial China operations but is not headquartered in mainland China.

## Sources

- Official website: https://www.cullgen.com/
- Gyre completes acquisition (SEC exhibit): https://www.sec.gov/Archives/edgar/data/1124105/000114036126018716/ef20072211_ex99-1.htm
- Gyre agreement announcement (PDF on Cullgen site): https://www.cullgen.com/s/Cullgen-Gyreagreementpressrelease-4c4h.pdf

## Connected records

- fronts: [Antibody-Drug Conjugates](https://onco.cc/fronts/adcs/), [Targeted Therapy](https://onco.cc/fronts/targeted-therapy/)
- technologies: [Degrader-antibody conjugate (DAC)](https://onco.cc/technologies/degrader-antibody-conjugate/), [PROTACs & molecular glues (targeted protein degradation)](https://onco.cc/technologies/protac-degrader/)

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JSON: https://onco.cc/api/v1/entities/cullgen.json