Pfizer’s tofacitinib meets primary endpoints in Ph III psoriasis study

US pharma giant Pfizer (NYSE:PFE) on Friday announced positive results from the Oral treatment Psoriasis Trial (OPT) Retreatment study today (A3921111), a Phase III study investigating tofacitinib for the treatment of adult patients with moderate-to-severe chronic plaque psoriasis.

This three-period study showed that tofacitinib, as a 5mg or 10mg pill taken twice daily, met its two primary efficacy endpoints. The safety profile of tofacitinib in OPT Retreatment was consistent with previous studies and there were no new safety findings in this trial.

The first primary endpoint of OPT Retreatment evaluated the maintenance of clinical response in patients who remained on tofacitinib after an initial treatment phase compared to patients who were switched to placebo (withdrawal phase). The second primary endpoint examined patients who lost half of their original clinical response during the withdrawal phase, and measured the proportion of these patients who regained their original clinical response after restarting treatment with tofacitinib. Throughout the study, the efficacy response was measured by the proportion of subjects achieving a Physician’s Global Assessment (PGA) response of “clear” or “almost clear” skin and the proportion of subjects achieving at least a 75% reduction in the Psoriasis Area and Severity Index (PASI75), two commonly used measures of efficacy in psoriasis.