Interleukin-1 (IL-1) receptor antagonist (anakinra) has been shown to be effective in steroid-dependent recurrent pericarditis resistant to nonsteroidal anti-inflammatory drugs (NSAIDs) and colchicine. We sought to evaluate the acute efficacy of anakinra given early in patients with acute pericarditis. We enrolled patients within 24 hours of presentation of a first or recurrent episode of acute pericarditis who were experiencing severe pain (≥6 in 11-point Likert scale), despite treatment with at least one dose of NSAIDs and of colchicine. The primary outcome was pain relief at 24 hours. Subcutaneous anakinra 100 mg was administered in all patients, whereas NSAIDs and colchicine were suspended for 24 hours. Serum levels of interleukin-6 (IL-6) were measured at baseline and 24 hours. Data are reported as median (interquartile range). We treated 5 patients (4 male and 1 female; 38 [31-54] years old). Anakinra significantly reduced pain from 6.0 (6.0-7.5) to 4.0 (2.5-4.0) at 6 hours (P = 0.012 vs. baseline) and to 2.0 (1.5-2.5) at 24 hours (P = 0.0025 vs. baseline). No patients required rescue pain medication. IL-6 levels were also significantly reduced from 95.3 (24.2-155.1) to 23.9 (4.5-71.9) pg/mL at 24 hours (P = 0.037). The reduction in pain intensity paralleled the reduction in IL-6 serum levels (R = +0.966, P = 0.007). No adverse events related to treatment occurred. The administration of anakinra given early in acute pericarditis treatment course rapidly and significantly improved chest pain from acute pericarditis. The improvement is correlated with a reduction in IL-6 levels.
Trial registration: ClinicalTrials.gov NCT03224585.