Multisystem Inflammatory Syndrome Therapies in Children: A Comparative Effectiveness Trial.

OBJECTIVE: To determine the anti-inflammatory medication--infliximab, steroids, or anakinra--that is most effective in treating intravenous immunoglobulins (IVIG)-resistant multisystem inflammatory syndrome in children (MIS-C). STUDY DESIGN: Two hospital, comparative effectiveness study comparing infliximab, methylprednisolone, and anakinra therapy in IVIG-resistant MIS-C patients. The primary outcome was the difference in the need for second randomization among the treatment arms. RESULTS: Of 73 MIS-C patients enrolled, 71 received their first randomization drug and completed the study. After adjusting for age and sex, the odds of needing second randomization were 3.4 times higher when the first randomized drug was anakinra compared with infliximab (OR=3.42, 95% CI: 1.03 - 12.29, p = 0.049) yet similar when the first randomized drug was steroids or infliximab. Twenty-eight adverse events were recorded, none of which were serious. Of these, 17 (60.7%) were adjudicated to be possibly, probably or definitely related to a study treatment with 16 (94.1%) attributed to steroids and 1 (5.9%) attributed to anakinra. CONCLUSIONS: In IVIG-resistant MIS-C, the odds of needing second randomization appear higher when the first randomized drug received was anakinra compared with infliximab or steroids. Infliximab or steroids may be more effective than anakinra as adjunctive therapy for MIS-C.