Abstract Body (Do not enter title and authors here): BACKGROUND: Anakinra (AK) and Rilonacept (RL) are increasingly being used as steroid sparing agents in the management of recurrent pericarditis due to their antagonism of the IL-1 mediated innate immune activation. However, it is uncertain whether they would show a similar response in reducing recurrence of Autoimmune Pericarditis (AP), since this is mediated by the adaptive immune system and this cohort was excluded from the AIRTRIP/RHAPSODY trials.
HYPOTHESIS: IL-1 antagonists (IL-1#) maintain clinical remission in AP refractory to other disease modifying therapy (DMT).
AIMS: To evaluate the efficacy and safety of IL-1# in treating pericarditis associated with autoimmune diseases.
METHODS: We retrospectively analysed 31 adults at our Pericardial Center with AP that was refractory to treatment with standard DMT aimed at managing the underlying disorder and were started on AK/RL after shared decision making with the patient and their rheumatologist. Markers of disease activity (serologic/imaging) and adverse effects were obtained during the treatment period.
RESULTS: The cohort included 80% females with median age 51 y with ≥ 2 verified recurrences on standard DMT and treated with AK (68%)/RL (32%) for a median of 21 months. Majority of the patients had rheumatoid arthritis and inflammatory colitis. IL-1# therapy was associated with decreased number of flares, C-reactive protein levels, and late gadolinium enhancement on cardiac magnetic resonance imaging, the former 2 parameters reaching statistical significance. 6 cases of infection were noted; 2 required IL-1# cessation. No malignancies, major cardiovascular events or death was noted during follow-up.
CONCLUSIONS: IL-1# (AK/RL) are associated with clinical improvement in patients with refractory AP, supporting the growing evidence from case reports in literature. This is the first study of this sample size analysing outcomes in patients with AP on IL-1#. This may suggest the presence of additional molecular immune pathways mediating recurrence in AP that need elucidation in future prospective studies.