Tofacitinib or Adalimumab vs Placebo for Patients With Psoriatic Arthritis

Treatment with tofacitinib 5 or 10 mg demonstrated superior efficacy to placebo in several clinical domains of psoriatic arthritis at 3 months, according to the results of a 12-month, phase 3, randomized, placebo-controlled, double-blind trial published in the New England Journal of Medicine.

A total of 422 patients were randomly assigned in a 2:2:2:1:1 ratio to receive 1 of 5 treatment regimens: oral tofacitinib 5 mg administered twice daily (n=107), oral tofacitinib 10 mg administered twice daily (n=104), subcutaneous adalimumab 40 mg administered once every 2 weeks (n=106), placebo with a blinded switch to tofacitinib 5 mg at 3 months (n=52), and placebo with a blinded switch to tofacitinib 10 mg at 3 months (n=53). Overall, after accounting for treatment discontinuations, treatment withdrawals, and protocol violations, 373 patients completed the trial.

The primary endpoints included both the proportion of patients with an American College of Rheumatology 20 (ACR20) response at 3 months and the change from baseline in the Health Assessment Questionnaire-Disability Index (HAQ-DI) score at 3 months.

ACR20 response rates at 3 months were 50% in the tofacitinib 5-mg group and 61% in the tofacitinib 10-mg group compared with 33% in the placebo group (P =.01 for the 5-mg dose vs placebo and P <.001 for the 10-mg dose vs placebo). In the adalimumab group, the ACR20 response rate at 3 months was 52%.

Mean change in HAQ-DI score was −0.35 in the tofacitinib 5-mg group and −0.40 in the tofacitinib 10-mg group (P =.006 for the 5-mg dose vs placebo and P <.001 for the 10-mg dose vs placebo). In the adalimumab group, the change in HAQ-DI score was −0.38.

The rates of adverse events through 12 months of treatment were 66% in the tofacitinib 5-mg group, 71% in the tofacitinib 10-mg group, 72% in the adalimumab group, 69% in the placebo group that switched to the tofacitinib 5-mg dose, and 64% in the placebo group that switched to the tofacitinib 10-mg dose. Among tofacitinib-treated patients, there were 4 cases of cancer, 4 cases of herpes zoster, and 3 serious infections reported during the trial.

The investigators concluded that in patients with psoriatic arthritis and a prior inadequate response to treatment with conventional disease-modifying antirheumatic drugs, the efficacy of tofacitinib was superior to that of placebo at 3 months.

This study was funded by Pfizer, the manufacturer of tofacitinib.

Reference

Mease P, Hall S, FitzGerald O, et al. Tofacitinib or adalimumab versus placebo for psoriatic arthritis. N Engl J Med. 2017;377(16):1537-1550.