Pfizer announces tasocitinib Phase 2 data for plaque psoriasis

Pfizer Inc. (NYSE: PFE) today announced that data from a Phase 2 efficacy and safety study of tasocitinib (proposed INN name for CP-690,550), the company's investigational oral JAK inhibitor, met its primary endpoint of a statistically significant greater proportion of patients achieving at least a 75 percent reduction from baseline in PASI (Psoriasis Area and Severity Index) at week 12 in individuals with chronic moderate to severe plaque psoriasis.  At week 12, PASI 75 responses for tasocitinib 2, 5 and 15 mg twice daily groups were 25.0%, 40.8% and 66.7% respectively, versus placebo, 2.0% (all doses, p<0.001).  As early as week 4, treatment with 5 and 15 mg twice daily of tasocitinib significantly improved patient reported health-related quality of life outcomes. These results were presented in two posters at the annual meeting of the European Academy of Dermatology and Venereology (EADV).

The double-blind, placebo-controlled, dose-ranging Phase 2 study was conducted in 197 adult patients with moderate to severe plaque psoriasis.  Study participants were randomized to receive 2, 5 or 15 mg tasocitinib or placebo twice daily.  In the study, the most frequently reported treatment-emergent adverse events were upper respiratory tract infection and headache.  

Three patients experienced a total of five serious adverse events during the study.  Dose dependent decreases in mean neutrophil counts and hemoglobin values and increases in mean LDL, HDL and total cholesterol levels were observed.