Firsekibart Beats Colchicine as Gout Flare Prophylaxis When Initiating ULT

Firsekibart was a more effective prophylaxis against acute gout flares compared with colchicine in patients initiating urate-lowering therapy (ULT), with a favorable tolerability profile in a new study published in ACR Open Rheumatology.1

“Given that colchicine, NSAIDs, and glucocorticoids are all associated with a range of side effects, there remains an unmet clinical need for alternative effective and well-tolerated treatments as prophylaxis against acute gout flares in patients with gouty arthritis initiating ULT,” study investigator Yiyun Yu, Department of Rheumatology and Immunology, Huashan Hospital, Fudan University, Shanghai, China, and colleagues wrote.1

These data are from a randomized, multicenter, open-label, active-controlled, phase 2 trial that randomized 162 participants (1:1:1) to receive a single subcutaneous injection of firsekibart 100 mg (n = 55) or 200 mg (n = 52) or oral colchicine 0.5 mg/day (n = 55) for 12 weeks. Participants initiated ULT at baseline or within 1 week before screening.1

Investigators found that the adjusted mean number of acute gout flares per participant was 0.02 with firsekibart 100 mg and 0.34 with colchicine, with a rate ratio of 0.05 (95% CI, 0.01–0.43; P.0060). Both treatment groups receiving firsekibart had a lower proportion of patients with at least 1 acute gout flare than the colchicine group. There were no treatment-emergent adverse events (AEs) leading to treatment discontinuation/study withdrawal with firsekibart-treated participants, no treatment-related serious AEs, and no deaths, supporting its favorable safety profile.1

“Gout is a highly prevalent disease with a rising global burden and is often associated with significant comorbidities. The findings in this study suggest that firsekibart may serve as a novel strategy for preventing acute gout flares in patients initiating ULT, potentially transforming the management paradigm for gout,” Yu and colleagues concluded.1

Study investigator Yu Xue, MD, also from Huashan Hospital, recently presented data on firsekibart from a multicenter, randomized, double-blind, double-dummy, active-controlled, phase 3 trial conducted across 51 centers in China at the American College of Rheumatology (ACR) Convergence 2025, held October 24–29 in Chicago, Illinois.

This trial included 311 patients, with 156 receiving firsekibart and 155 receiving compound betamethasone (CB). Xue and colleagues found that firsekibart significantly delayed median time to first new flare (Not estimable vs. 45 days) and reduced the risk of new flare by 90% (HR, 0.10; 95% CI, 0.06-0.17; P <.0001) over 12 weeks and by 87% (HR, 0.13; 95% CI, 0.08-0.21; P <.0001) over 24 weeks.2

Pain intensity and the median time to reduce ≥50% pain was similar, but firsekibart showed better pain relief in patients from 48 hours to 7 days. Furthermore, significantly fewer patients treated with firsekibart experienced ≥ 1 new flare over 12 weeks (10.9% vs. 65.2%) and 24 weeks (14.7% vs. 66.5%; both P <.0001), and the mean number of new flares per patient was lower in firsekibart group over 12 weeks (0.2 [standard deviation (SD), 0.52] vs. 1.2 [SD, 1.27]) and 24 weeks (0.2 [SD, 0.79] vs. 1.6 [SD, 1.79]). A smaller proportion of patients receiving firsekibart required rescue therapy (10.9%) compared to those receiving CB (48.4%) and a lower mean dosage of rescue medicine was used in the firsekibart group (corticosteroid use, 69.33 mg vs 202.03 mg). Safety profiles were similar between groups.2

“Millions of people with gout struggle with inadequate treatment options, especially those living with kidney disease or uncontrolled disease despite standard therapy,” an ACR spokesperson said in a statement about recent gout data presented at the conference, including Xue’s study.3 “The results presented at ACR Convergence this year highlight encouraging new approaches that could transform care for some of the most difficult-to-treat patients.”

References

1. Yu Y, Xue Y, Hu J, et al. Firsekibart as a Prophylactic Treatment for Acute Gout Flare in Participants Initiating Urate‐Lowering Therapy: A Phase 2, Randomized, Open‐Label, Multicenter, Active‐Controlled Trial. ACR Open Rheumatol. 2025;7(11). doi: 10.1002/acr2.70111

2. Xue Y, Chu T, Hu J, et al. Efficacy and Safety of Firsekibart in Acute Gouty Arthritis Patients with Limited Treatment Options: A Multicenter, Randomized, Double-Blind, Double-Dummy, Active-Controlled Phase III Trial. Presented at: ACR Convergence 2025; October 24-29; Chicago, Illinois. Abstract #2013

3. New Gout Therapies Show Promise in Phase III Trials at ACR Convergence 2025. News release. ACR. October 25, 2025. https://rheumatology.org/press-releases/new-gout-therapies-show-promise-in-phase-iii-trials-at-acr-convergence-2025