Spyre Therapeutics Inc. shares fell 14% in extended trading on Tuesday after the company reported Phase 2 trial results for its experimental rheumatoid arthritis drug SPY072 that met statistical significance on some measures but did not align with internal development priorities.
The SKYWAY Phase 2 trial enrolled 143 participants across three arms: 48 received a high dose of SPY072, 48 a low dose, and 47 a placebo. The low-dose cohort achieved a statistically significant improvement in the primary endpoint, with a change from baseline in DAS28-CRP of -1.9 versus -1.3 for placebo at 12 weeks. The high-dose group posted a 63% ACR20 response rate compared with 43% for placebo, while the low-dose group reached 38% for ACR50 versus 19% for placebo.
The drug candidate was well tolerated, with adverse events reported in 27% of SPY072-treated participants versus 36% in the placebo group, and most events were mild to moderate. Despite the positive efficacy signals, Spyre indicated that the magnitude of benefit did not meet its internal criteria to prioritize monotherapy development of SPY072 for rheumatoid arthritis, driving the post-results selloff.
Looking ahead, Spyre expects topline data for SPY072 in psoriatic arthritis and axial spondyloarthritis in the fourth quarter of 2026, with additional results for a combination therapy in hidradenitis suppurativa anticipated in late 2027 or early 2028.
