At a Glance
- Company: Coultreon Biopharma
- Location: Leuven, Belgium
- Deal value: $125M Series A
- Focus area: Oral SIK3 inhibitor for autoimmune disease
- Next steps: Phase 2 in psoriasis and ulcerative colitis
What happened?
Coultreon Biopharma closed an oversubscribed $125 million Series A financing to advance its immunology pipeline, led by lead asset COL-5671. The round was led by Sofinnova Investments, with Forbion and Novo Holdings as co-leads, and included Galapagos, Regeneron Ventures and several other investors.
Why does it matter?
COL-5671 is a highly selective, oral once-daily SIK3 inhibitor designed to target core inflammatory pathways across autoimmune diseases. If successful, it could offer a more targeted approach than existing immunology drugs, with Phase 2 data in psoriasis and ulcerative colitis now planned as the first major proof-of-concept readout.
Who’s behind it?
Coultreon is the rebranded successor to Onco3R Therapeutics, a Belgian biotech focused on immunology. The company acquired full ownership of COL-5671 from Galapagos in April 2025, and its shareholder base now includes a mix of specialist biotech funds and large strategics.
How was it achieved?
The financing was oversubscribed, reflecting investor interest in both the target biology and the team’s plan to move quickly from Phase 1 into mid-stage autoimmune trials. Coultreon says it will use the funds to start Phase 2 studies in psoriasis and ulcerative colitis and aims to generate clinical proof-of-concept in 2027.
What’s next?
Coultreon plans to advance COL-5671 into Phase 2 and broaden its potential across other immune-mediated diseases, including Crohn’s disease and rheumatoid arthritis. The company’s next data set will be important for confirming whether SIK3 inhibition can translate into a differentiated autoimmune drug class.