BACKGROUND: Idiopathic recurrent pericarditis (IRP) is a rare autoinflammatory disease. Interleukin (IL)-1α and IL-1β are the pivotal cytokines in the pathophysiology of acute pericarditis and its recurrence. We created a phase II/III study with a new IL-1 inhibitor-goflikicept in IRP.

OBJECTIVES: This study sought to evaluate the efficacy and safety of goflikicept treatment in patients with IRP.

METHODS: We conducted a 2-center open-label study of goflikicept in patients with IRP with and without recurrence at time of enrollment. The study consisted of 4 periods: screening, run-in (open-label treatment period), randomized withdrawal, and follow-up. Patients with clinical response to goflikicept in the run-in period were randomized (1:1) to a placebo-controlled withdrawal period, where the time to first pericarditis recurrence (primary endpoint) was evaluated.

RESULTS: We enrolled 22 patients, and 20 of these patients were randomized. Reduction of C-reactive protein level accompanied by reduction of chest pain and pericardial effusion compared to baseline was demonstrated during the run-in period. Recurrence of pericarditis occurred in 9 of 10 patients in the placebo group, and there were no recurrence events in goflikicept group within 24 weeks after randomization (P < 0.001). A total of 122 adverse events were reported in 21 patients (95.5%), with no deaths and no new safety signals identified for goflikicept.

CONCLUSIONS: Treatment with goflikicept prevented recurrences and maintained IRP remission with a favorable risk-benefit ratio. Goflikicept reduced the risk of recurrence compared with placebo. (Study to Evaluate the Efficacy and Safety of RPH-104 Treatment in Patients With Idiopathic Recurrent Pericarditis; NCT04692766).