Faecal microbiota transplantation dashes hope in psoriatic arthritis

Faecal microbiota transplantation (FMT) does not appear to be beneficial in the treatment of active peripheral psoriatic arthritis (PsA), with a recent study showing that although FMT does not increase the incidence of serious adverse events, it is inferior to sham.

The study enrolled 97 adult patients with active peripheral PsA (≥3 swollen joints) despite continuous treatment with methotrexate. Of these, 31 patients (32 percent) were randomly assigned to receive one gastroscopic-guided FMT (n=15) or sham transplantation into the duodenum (n=16).

Thirty patients (97 percent) completed the 26-week clinical evaluation. None of them developed any serious adverse events.

The primary efficacy endpoint treatment failure (ie, needing treatment intensification) occurred with greater frequency in the FMT than the sham group: nine vs three patients, respectively (60 percent vs 19 percent; risk ratio, 3.20, 95 percent confidence interval [CI], 1.06–9.62; p=0.018).

Results for key secondary endpoints including Health Assessment Questionnaire Disability Index (HAQ-DI) and American College of Rheumatology (ACR20) response were no better. HAQ-DI showed a greater improvement with sham than with FMT (0.30 vs 0.07), with a difference of 0.23 points (95 percent CI, 0.02–0.44; p=0.031). Meanwhile, there was no between-group difference in the proportion of ACR20 responders (7 of 15 [47 percent] vs 8 of 16 [50 percent]).

Some evidence suggests that targeting dysbiosis of the intestinal microbiota via FMT may work against inflammatory diseases, although causality remains to be established. The present data provide evidence that FMT may not be useful in the treatment of PsA.