Spyre Therapeutics (NASDAQ: SYRE) announced that its experimental drug SPY001 met its primary endpoint in a Phase 2 trial for moderate-to-severe ulcerative colitis patients.

The SKYLINE trial showed SPY001 achieved a statistically significant reduction of 9.2 points in Robart's Histopathology Index score at 12 weeks, with a p-value of less than 0.0001. Secondary endpoints included a 40% clinical remission rate and 51% endoscopic improvement rate.

SPY001 is an extended half-life antibody targeting α4β7, an integrin involved in immune cell trafficking to the gut. The drug was designed to improve upon vedolizumab's activity by maintaining the same epitope and potency while providing extended half-life and greater induction dosing.

The trial enrolled 43 patients in Part A, an open-label assessment. Six subjects experienced treatment-emergent adverse events during the induction period, with one serious adverse event deemed unrelated to the drug. The most common adverse event was back pain, occurring in two patients.

Spyre closed recruitment for Part A and opened enrollment for Part B, which includes monotherapy cohorts for SPY001, SPY002, and SPY003, plus three combination therapy cohorts. The company expects proof-of-concept data for SPY002 in mid-2026 and SPY003 in the third quarter of 2026. Part B induction data for all cohorts remains on track for 2027.

The Massachusetts-based biotechnology company is developing long-acting antibodies for inflammatory bowel disease and rheumatic diseases. Its pipeline includes investigational antibodies targeting α4β7, TL1A, and IL-23.