An empirically generated responder definition for rosacea treatment.

Objective: The aim of this study was to empirically generate a responder definition for the treatment of papulopustular rosacea.

Methods: A total of 8 multicenter clinical studies on patients with papulopustular facial rosacea were analyzed. All patients were treated with azelaic acid and/or comparator treatments. The severity of rosacea was described by the Investigator Global Assessment (IGA) and the number of lesions. Patients with the IGA score of "clear/minimal" were considered as responders, and those staying in the range of IGA "mild to severe" as nonresponders. The respective number of lesions was determined.

Results: A total of 2,748 patients providing 12,410 measurements were included. After treatment, responders showed 2.23±2.48 lesions (median 2 lesions [0-3]), and nonresponders showed 13.74±10.40 lesions (median 12 lesions [6-18]). The optimal cutoff point between both groups was 5.69 lesions.

Conclusion: The calculated cutoff point of 5.69 lesions allows discrimination of responders (5 or less remaining lesions) and nonresponders (6 or more remaining lesions) of therapeutic interventions in rosacea.