Spyre’s SPY003 Hits Primary Endpoint in UC Trial, Completing IBD Portfolio Proof-of-Concept — Spyre Therapeutics, Inc.

Event summary

SPY003 (anti-IL-23) met primary endpoint with 10.0-point reduction in RHI score (p<0.0001) at Week 12 in Phase 2 SKYLINE trial Part A.
Secondary endpoints included 20% clinical remission rate and 30% endoscopic improvement.
SPY003 was well-tolerated with safety profile consistent with IL-23 class.
SKYLINE Part B enrolling with topline induction data expected in 2027.
Spyre now has proof-of-concept for all three IBD combination components (SPY001, SPY002, SPY003).

The big picture

Spyre’s completion of proof-of-concept for all three IBD combination components underscores its strategy of optimizing individual antibodies to create superior combination therapies. The biotech is positioning itself to challenge current standards of care in ulcerative colitis with a focus on efficacy, safety, and simplified treatment regimens. The next critical phase will be demonstrating the additive benefits of these combinations in SKYLINE Part B.

What we're watching

Combination Strategy: Whether Spyre’s pairwise combinations (SPY120, SPY130, SPY230) can deliver best-in-disease efficacy and safety profiles.
Execution Risk: The pace at which Spyre can enroll and generate topline data from SKYLINE Part B by 2027.
Market Differentiation: How SPY003’s extended half-life and potential best-in-class status will position it against existing IL-23 therapies.