Efficacy and safety of treatments in familial Mediterranean fever and its complications: a systematic review informing the EULAR/PReS recommendations for familial Mediterranean fever

Objectives: To analyse the efficacy and safety of (1) the biological agents and tofacitinib in the treatment of familial Mediterranean fever (FMF); (2) the biological agents and tofacitinib in FMF patients with complications such as amyloidosis; and (3) the colchicine preparations and dosing strategies to serve as evidence supporting the updated European Alliance of Associations for Rheumatology (EULAR) recommendations. Methods: This was a systematic review (SR) of studies testing pharmacological treatments in FMF patients, including targets, dosing, tapering, and uses in AA amyloidosis. MEDLINE, Embase, and the Cochrane Library were searched, focusing on studies published after October 1, 2014. The Cochrane Risk of Bias tool and the Newcastle-Ottawa Scale were used to assess the risk of bias in the included randomised controlled trials (RCTs) and observational studies, respectively. Due to excess heterogeneity, results were synthesised qualitatively. Results: This SR included 42 studies for efficacy and safety (n = 1798 patients), 13 for tapering, and 31 for amyloidosis. Based on 6 RCTs of interleukin (IL)-1 blockers and observational studies, these biologicals seem to be effective in decreasing the number of attacks and acute-phase reactants and improving disease activity scores and patient-reported outcomes. They also seem relatively safe. An RCT showed the equivalence of once-daily vs twice-daily doses of colchicine. The evidence of AA amyloidosis was entirely observational but reassuring for a deadly complication. Conclusions: Biological agents, particularly IL-1 inhibitors, are effective and relatively safe options for FMF patients who do not respond to colchicine. These treatments may be promising alternatives for managing symptoms and preventing comorbidities in both paediatric and adult populations.