Pfizer has reported positive top-line data from a Phase III clinical trial of its abrocitinib (PF-04965842), which met the primary and key secondary endpoints in moderate to severe atopic dermatitis (AD) patients aged 12 and older.

The trial compared the safety and efficacy of the investigational, oral Janus kinase 1 (JAK1) inhibitor to that of placebo in a total of 387 participants. A 200mg and 100mg dose of abrocitinib were studied over 12 weeks.

Data revealed that the proportion of subjects who achieved each co-primary efficacy endpoint and each key secondary endpoint was statistically significantly higher with abrocitinib compared to placebo by week 12.

The co-primary endpoints of the trial were an Investigator Global Assessment (IGA) score of clear (0) or almost clear (1) skin and two-point improvement, and at least a 75% or greater change in their Eczema Area and Severity Index (EASI) score from baseline.

Key secondary endpoints were a four-point or more decrease in itch severity measured using the pruritus numerical rating scale (NRS), and the magnitude of decrease in the Pruritus and Symptoms Assessment for Atopic Dermatitis (PSAAD).

A statistically significant number of patients on the study drug also showed response during the initial two to four weeks after the first dose.

Both doses of the therapeutic were well-tolerated without any unexpected safety events. Moreover, discontinuation rates due to adverse events were observed to be low in the treatment groups compared to placebo.

Pfizer Global Product Development Inflammation & Immunology chief development officer Michael Corbo said: “Moderate to severe atopic dermatitis is a chronic, inflammatory skin disease that can take both a physical and emotional toll on the millions of patients living with the condition worldwide.

“These top-line findings are encouraging and provide evidence that abrocitinib, if approved, could be an effective new oral once-daily treatment option for patients.”

In February last year, abrocitinib secured breakthrough therapy designation from the US Food and Drug Administration (FDA) in moderate to severe AD.