Adult-onset Still's disease (AOSD) is a rare inflammatory disease, typically characterized by spiking fever, skin rash, and arthralgia or arthritis. Its conventional treatment includes NSAIDs and corticosteroids, and DMARDs as second-line therapy. Frequently, IL-1 inhibitors are also required, mainly in patients refractory to traditional therapy. Canakinumab is a monoclonal antibody that binds IL-1β with high affinity and specificity, making it appropriate for therapeutic purposes in AOSD.
The aim of this systematic review was to identify and compile the current data on the efficacy and safety of canakinumab in the treatment of AOSD.
Following the guidelines established by the PRISMA statement, we searched Scopus, Web of Science, Pubmed, and Cochrane Library for relevant literature up to March 2021. The inclusion criteria comprised: randomized controlled trials, pooled analyses, observational studies, case series, and case reports.
Seventeen studies published from 2012 to 2021 were evaluated; 11 of these correspond to case series or case reports, four observational studies, one placebo-controlled phase II trial, and one analysis of pooled systemic juvenile idiopathic arthritis data. In general, out of a total of 99 patients, 68.7% of these presented a complete remission of the systemic and arthritic manifestations at the end of the observation period, while 16.2% of the patients showed a partial improvement of the symptoms and the remaining (15.1%) did not show clinical improvement or were excluded. Moreover, 210 adverse events were reported in 69 patients during canakinumab treatment, of which the majority correspond to respiratory tract infections, arthralgia, disease flares, abdominal pain, nausea, and diarrhea, whereas the most common severe adverse events included macrophage activation syndrome and serious infections. Also, a corticosteroid-sparing effect was observed in a large percentage of patients.
More studies with solid evidence are needed to support the efficacy of canakinumab in AOSD, although its use is encouraged by the increasing favorable results reported and the efficacy of other IL-1 inhibitors. It was also associated with an acceptable safety profile, similar to expected in IL-1 inhibitor therapy. However, future studies with well-defined endpoints are warranted to examine further the usefulness of canakinumab in AOSD.