INF904 Phase 2a Trial Results: A Potential New Horizon for HS and CSU Management

Phase 2a data on oral C5aR inhibitor INF904 show early efficacy and a favorable safety profile in both hidradenitis suppurativa (HS) and chronic spontaneous urticaria (CSU) with rapid symptom improvement and no serious adverse events across tested doses.

In the HS cohort, there were reductions in abscess and nodule counts and draining-tunnel counts, with concurrent improvements in pain (NRS30), Dermatology Life Quality Index (DLQI), and HiSCR by week 4.

For the CSU cohort, UAS7 and UCT7 analyses showed clinically relevant reductions, with the 60 mg cohort demonstrating the largest mean UAS7 drop at week 4 and symptom benefit appearing as early as Week 1. These rapid-onset changes suggest earlier symptomatic control than is typical for some longer-acting agents and may recalibrate expectations for speed of relief in CSU if confirmed.

Safety and tolerability appeared acceptable across tested doses: no serious adverse events or emergent safety signals were reported, and common adverse events were generally mild with no clear dose-limiting pattern.