Samant, Manoj

Introduction: Rare cardiac complications of COVID-19 and COVID-19 mRNA vaccination include pericarditis and myocarditis. Patients with recurrent pericarditis may be at increased risk of triggered recurrence. The known efficacy of the interleukin (IL)-1 antagonist rilonacept in treating and preventing recurrence could inform COVID-19 disease and vaccination management. Methods: The Phase 3 trial RHAPSODY was a global, double-blind, placebo-controlled, randomized-withdrawal study. A long-term extension (LTE) enabled up to 24 months further open-label treatment from May 2020 until June 2022. Concomitant vaccination data and adverse events, including COVID-19, were collected. Results: No COVID-19 cases were reported during the run-in and randomized withdrawal periods (n=86). As of the 6 May 2022 data cutoff, a COVID-19 AE was reported in 19% (14/74) of LTE subjects, of whom 12 were on rilonacept: 5 of 44 fully-vaccinated (≥14 days beyond second serial dose) subjects (11.4%) and 9 of 30 unvaccinated or partially-vaccinated subjects (30.0%). Of the fully-vaccinated subjects, 1 case occurred ~11 months post primary vaccination cycle (no booster). COVID-19 severity was mild (n= 11), moderate (n=2), or severe (n=1). All cases resolved except the severe AE complicated by comorbidities; the subject discontinued. Of 12 subjects receiving rilonacept at the time of COVID-19 diagnosis, 10 maintained dosing with rilonacept, 1 interrupted rilonacept for ~4 weeks, and 1 discontinued rilonacept permanently; none experienced a pericarditis recurrence (PR) after the AE. The remaining 2 subjects had previously interrupted rilonacept for off-treatment observation: one had a PR >4.5 months after suspending rilonacept and 18 days after COVID-19 resolution; no PR in the other (>6 months). There were no PR AEs associated with COVID-19 vaccination (all subjects were receiving rilonacept). Conclusions: In patients on rilonacept in this study, although numbers are small, vaccination reduced COVID-19 events, pericarditis recurrence was not increased by vaccination or disease, and no pericarditis recurrences occurred during rilonacept treatment. One pericarditis recurrence occurred remotely after rilonacept suspension in the peri-COVID-19 period.

Introduction: Rilonacept reduced pericarditis recurrence in the phase 3 trial RHAPSODY. The long-term extension (LTE) enabled further insights into efficacy, safety, and clinical decision making. Methods: The RHAPSODY run-in (RI) and randomized-withdrawal periods were followed by an LTE that enabled open-label rilonacept treatment up to 24 additional months. A decision at 18 months after the most recent recurrence was based on clinical status at investigator discretion: 1) continue rilonacept on-study, 2) suspend rilonacept for observation or 3) discontinue from the LTE without observation. Endpoints included recurrence and quality of life. Results: In May 2020, 74 of 75 eligible subjects continued to LTE; US subjects (n=45) switched to commercial therapy or discontinued in April 2021 (treatment duration from RI baseline [median; maximum] 18; 27 months). Non-US subjects (n=29) completed the LTE in June 2022 (treatment duration from RI baseline [median; maximum] 27; 33 months). Concomitant oral medications during LTE: 22% NSAIDS, 20% colchicine, 0% corticosteroids, 43% none. Inflammation signs (CRP), RP symptoms (PGIPS), and recurrences were low on-treatment. Before the 18-month decision (n=74), there were 3 investigator-assessed recurrences (0.04 per patient-year). At the 18-month decision (n=52), 64% (n=33) continued rilonacept on-study, 15% (n=8) suspended rilonacept for observation, and 21% (n=11) discontinued the study without observation, of whom 7 switched to commercial rilonacept. There was a 75% recurrence rate (n=6/8) in the off-treatment observation group (median time to event 11.8 [3.7, Not-Estimable (NE)] weeks) but only 1 recurrence in subjects on rilonacept (time to event NE [too few events]) associated with a 4-week interruption; HR 0.018, p<0.0001; Fig 1. Conclusions: Continued rilonacept treatment resulted in continued treatment response, whereas treatment suspension at 18 months may be associated with pericarditis recurrence.