ARTICLE | Emerging Company Profile
Coultreon: Building a cleaner SIK3 inhibitor for autoimmune disease
Backed by a $125M series A, the Galapagos spinout believes selective SIK3 inhibition can avoid the toxicity that constrained a dual SIK2/3 inhibitor
August 6, 2026 10:41 PM UTC
With a more selective small molecule, Coultreon aims to achieve what its former parent Galapagos could not: biologic-like suppression of inflammatory cytokines through SIK3 inhibition, without the toxicity that prevented its predecessor from adequately engaging the target.
The Belgian biotech’s lead program, once-daily oral prodrug COL-5671, is in Phase I testing. ...