A Post-Hoc Analysis of the 48-Week Data from Study 301 of Firsekibart for Acute Gouty Arthritis: Evaluation of Number of Doses and Switching-to-Firsekibart Efficacy

Abstract

Objective: This post-hoc analysis aimed to evaluate the number of Firsekibart administrations over 48 weeks in patients with acute gout and the efficacy of switching to Firsekibart treatment during the open-label period in patients who had recurrent flare recurrence on compound betamethasone. Methods: We performed a post-hoc analysis on the 48-week treatment data from the 301 study (a multicenter, randomized, double-blind, active-controlled Phase III clinical trial) of Firsekibart for acute gout. A total of 312 patients with acute gout were randomized to receive either Firsekibart 200 mg subcutaneously or compound betamethasone 7 mg intramuscularly during the 24-week double-blind period, followed by a 24-week open-label period. After the initial dose, patients could receive additional doses upon gout flare; those with an inadequate response could receive oral prednisone as rescue therapy. During the open-label period, patients in the betamethasone group who experienced gout flares could switch to Firsekibart treatment. Differences in the number of doses between the two groups over 48 weeks, differences in the number of doses before and after switching to Firsekibart treatment in the betamethasone group, and the proportion of patients experiencing at least one gout flare after switching were analyzed. Results: Over 48 weeks, the median number of doses in the Firsekibart group was 1.0 (Q1, Q3: 1.0, 2.0), which was significantly lower than that in the compound betamethasone group (2.0 [1.0, 3.0]), P < 0.0001. For patients who switched from compound betamethasone to Firsekibart treatment, the median number of doses after switching was 1.0 (1.0, 1.0), markedly lower than the 2.0 (1.0, 3.0) before switching (P < 0.0001). During the open-label period, 69 patients (44.2%) in the betamethasone group switched to Firsekibart treatment, of whom only 2 (2.9%) experienced a gout flare. This recurrence rate was significantly lower than that observed during the double-blind period while receiving compound betamethasone (2.9% vs. 82.6%, P < 0.001). Conclusion: The median annual number of doses of Firsekibart for treating acute gout flares is one dose per year. For patients with inadequate response to corticosteroid therapy, Firsekibart demonstrates favorable efficacy and dosing convenience in controlling gout flares, representing a valuable new option for long-term gout management.