Pfizer Inc. announced top-line results from its first phase 3 study investigating tofacitinib for the treatment of psoriatic arthritis, Oral Psoriatic Arthritis triaL (OPAL) Broaden. This study evaluated the efficacy and safety of tofacitinib 5 mg and 10 mg twice daily (BID) in adult patients with active psoriatic arthritis (PsA) who had an inadequate response to at least one conventional synthetic disease-modifying antirheumatic drug (csDMARD) and who were tumour necrosis factor inhibitor (TNFi)-naïve.

OPAL Broaden met its primary efficacy endpoints demonstrating that both tofacitinib 5 mg BID and 10 mg BID were superior to treatment with placebo at 3 months as measured by American College of Rheumatology 20 (ACR20) response and Health Assessment Questionnaire Disability Index (HAQ-DI) score.

“As a chronic inflammatory disease, psoriatic arthritis can have a significant impact on a person’s daily life. Despite available therapies, including biologic and oral treatments, there remains an unmet need for additional options,” said Michael Corbo, Category Development Lead, Inflammation & Immunology, Pfizer Global Innovative Pharmaceuticals Business. “The results seen in the OPAL Broaden study are encouraging as they suggest that tofacitinib may have the potential to offer an additional effective oral option for patients living with psoriatic arthritis. We look forward to sharing detailed results at a future scientific meeting.”

OPAL Broaden is a phase 3 placebo-controlled study that investigated the efficacy and safety of tofacitinib 5 mg and 10 mg BID in treating the signs and symptoms of PsA, and improvement in physical function in patients with active PsA who had an inadequate response to at least one csDMARD due to lack of efficacy or adverse event, and who were TNFi-naive. Patients enrolled in the study were required to be on one csDMARD as background therapy and continue that dose for the duration of the study. The study also included adalimumab 40 mg subcutaneously administered every 2 weeks (q2 wk) as an active control arm. However, this study was not powered for non-inferiority or superiority comparisons between tofacitinib and adalimumab. A total of 422 patients were randomized in a 2:2:2:1:1 ratio to the following treatment arms: tofacitinib 5 mg BID, tofacitinib 10 mg BID, adalimumab 40 mg q2 wk, placebo to tofacitinib 5 mg BID and placebo to tofacitinib 10 mg BID treatment sequences.

Overall safety findings in this study were consistent with those observed in the broader rheumatology clinical development program for tofacitinib. All treatment groups had similar rates of treatment-emergent adverse events, serious adverse events, and discontinuations due to adverse events over the 12-month duration of the study. Serious adverse events observed were similar to those seen in other clinical development programs for tofacitinib.

The OPAL global clinical development program includes two phase 3 studies, OPAL Broaden and OPAL Beyond, as well as a long-term extension trial, OPAL Balance. Results for OPAL Beyond are anticipated in the first half of 2016. We expect that these three studies will form the potential submission package for possible future regulatory applications seeking expansion of the Xeljanz (tofacitinib citrate) label to include a PsA indication.

Xeljanz/Xeljanz XR is a prescription medicine called a Janus kinase (JAK) inhibitor. Xeljanz XR 11 mg is the first and only once-daily oral JAK inhibitor for the treatment of moderate to severe rheumatoid arthritis (RA).

As the developer of Xeljanz/Xeljanz XR, Pfizer is a leader in JAK innovation. Xeljanz/Xeljanz XR does not require injections or infusions. Xeljanz/Xeljanz XR can be taken with or without methotrexate.

Xeljanz is approved in more than 45 countries around the world for the treatment of moderate to severe RA as a second-line therapy after failure of one or more disease-modifying antirheumatic drugs (DMARDs).

Pfizer is committed to advancing the science of JAK inhibition and enhancing understanding of Xeljanz through a robust clinical development program. The efficacy and safety profile of Xeljanz has been studied in approximately 6,200 patients with moderate to severe RA, amounting to more than 19,400 patient-years of drug exposure in the global clinical development programme.

Xeljanz is the only JAK inhibitor included in the 2015 American College of Rheumatology Guideline for the Treatment of Rheumatoid Arthritis.