Pfizer Inc.  announced top-line results from two pivotal phase 3 trials from the oral treatment Psoriasis Trials (OPT) programme, OPT Pivotal #1 (A3921078) and OPT Pivotal #2 (A3921079), evaluating the efficacy and safety of tofacitinib, an oral Janus kinase (JAK) inhibitor, the first in a new class of medicines being investigated for the treatment of moderate-to-severe plaque psoriasis.

The OPT Pivotal #1 and OPT Pivotal #2 studies showed that tofacitinib, as a 5 mg or a 10 mg dose taken as a pill twice-daily, met the primary efficacy endpoints of statistically significant superiority over placebo at Week 16 in the proportion of subjects achieving a Physician’s Global Assessment response of “clear” or “almost clear,” and the proportion of subjects achieving at least a 75% reduction in Psoriasis Area and Severity Index, two commonly used measures of efficacy in psoriasis.

No new safety signals for tofacitinib were observed in the OPT Pivotal #1 or OPT Pivotal #2 studies. Detailed analyses of these studies, including additional efficacy and safety data, will be submitted for presentation at a future scientific meeting.

“Psoriasis is a long-term disease with no cure that can have a significant impact on patients. Although it is one of the most common chronic inflammatory diseases, many psoriasis patients remain untreated, undertreated or dissatisfied with their treatment, according to recently published surveys,” said Dr. Steven Romano, Global Medicines Development Lead for the Pfizer Global Innovative Pharmaceutical business. “Tofacitinib is the first in a new class of investigational psoriasis treatments, and I am encouraged by our phase 3 results to-date that demonstrate the potential of tofacitinib to be an important new treatment option for adults with moderate-to-severe chronic plaque psoriasis.”

Top-line results from the first two studies from the OPT Programme, OPT Compare and OPT Retreatment, were previously announced in October 2013, and these four studies, in addition to a long-term extension study, will form the planned psoriasis submission package to regulatory authorities in various markets. Pfizer currently intends to submit a supplemental New Drug Application (sNDA) to the US Food and Drug Administration (FDA) for the approval of tofacitinib 5 mg and 10 mg twice-daily for the treatment of adults with moderate-to-severe chronic plaque psoriasis by early 2015.