Objectives: Due to the rarity of relapsing polychondritis (RP), no randomised clinical trial has been conducted to date and treatment remains empirical. We performed a systematic literature review to assess the efficacy of the main conventional immunosuppressants and biotherapies used in RP.
Methods: We searched MEDLINE for original articles without language restriction. Abstracts from American College of Rheumatology (ACR) and European Alliance of Associations for Rheumatology (EULAR) were also considered for inclusion. Observational studies and clinical trials reporting on the efficacy of conventional immunosuppressants and biotherapies in adult patients with RP were selected and pooled response rates for each treatment were computed.
Results: Of 304 articles and abstracts identified, 31 underwent full-text review, and 11 were included. The studies involved a total of 177 patients, exposed to a total of 247 lines of treatments. The main treatments studied (by number of lines) were: TNF inhibitors (TNFi), n=92; methotrexate (MTX), n=38; tocilizumab (TCZ), n=26; anakinra (ANA), n=21; rituximab (RTX), n=16; abatacept (ABT), n=14; cyclophosphamide (CYC), n=14; azathioprine (AZA), n=13. The pooled response rates across studies were: 72% [95% CI: 42-95] for ABT, 66% [95% CI: 49-82] for TCZ, 64% [95% CI: 53-74] for TNFi, 56% [95% CI: 37-73] for MTX, 47% [95% CI: 26-68] for ANA, 43% [95% CI: 20-68] for RTX. Based on more limited data, response rates for AZA and CYC ranged from 38 to 100% and from 25 to 100%, respectively.
Conclusions: In this systematic review of available evidence regarding the treatment of relapsing polychondritis, ABT, TCZ and TNFi were the drugs associated with the best outcomes. ABT efficacy must be interpreted in light of the small number of patients treated. While MTX had slightly less efficacy, it is one of the drugs for which data are the most robust.