Pooled analysis of data from two Phase III trials with Pfizer’s JAK inhibitor Xeljanz (tofacitinib) add further support to the drug’s use as a treatment for moderate to severe psoriasis.

Pfizer said the results - which were included in a recent US filing for the drug - show that both tofacitinib 10mg and 5mg tablets twice daily were superior to placebo in achieving a Physician’s Global Assessment (PGA) response of “clear” or “almost clear”, as well as at least a 75% reduction in Psoriasis Area and Severity Index (PASI75).

Secondary endpoints - including the proportion of patients achieving _90% reduction in PASI (PASI90) and the percent change from baseline in Body Surface Area - were also met, and no new safety signals were observed, with the most common side effects reported being nasopharyngitis, upper respiratory infection and headache.

According to lead investigator Kim Papp, of Probity Medical Research, the data “underscore that if approved, tofacitinib may offer a clinically meaningful option in oral therapy as the first potential treatment in a new class of medicines for this chronic condition”.

Xeljanz was issued a green light by the US Food and Drug Administration in 2012 as the first JAK inhibitor approved to treat rheumatoid arthritis, and the regulator is currently considering its use for the treatment of adults with moderate to severe chronic plaque psoriasis who are candidates for systemic therapy or phototherapy. A decision on this is expected in October 2015.