Rosacea is a chronic inflammatory disorder that may negatively impact patients’ quality of life (QOL).1,2 Papulopustular rosacea (PPR) is characterized by centrofacial inflammatory lesions and erythema as well as burning and stinging secondary to skin barrier dysfunction.3-5 Increasing rosacea severity is associated with greater rates of anxiety and depression and lower QOL6 as well as low self-esteem and feelings of embarrassment.7,8 Accordingly, assessing patient perceptions of rosacea treatments is necessary for understanding its impact on patient health.6,9
The Rosacea International Expert Group has emphasized the need to incorporate patient assessments of disease severity and QOL when developing therapeutic strategies for rosacea.7 Ease of use, sensory experience, and patient preference also are important dimensions in the evaluation of topical medications, as attributes of specific formulations may affect usability, adherence, and efficacy.10,11
An azelaic acid (AzA) 15% foam formulation, which was approved by the US Food and Drug Administration in 2015, was developed to deliver AzA in a vehicle designed to improve treatment experience in patients with mild to moderate PPR.12 Results from a clinical trial demonstrated superiority of AzA foam to vehicle foam for primary end points that included therapeutic success rate and change in inflammatory lesion count.13,14 Secondary end points assessed in the current analysis included patient perception of product usability, efficacy, and effect on QOL. These patient-reported outcome (PRO) results are reported here.
Methods
Study Design
The design of this phase 3 multicenter, randomized, double-blind, vehicle-controlled, parallel-group clinical trial was described in more detail in an earlier report.13 This study was approved by all appropriate institutional review boards. Eligible participants were 18 years and older with moderate or severe PPR, 12 to 50 inflammatory lesions, and persistent erythema with or without telangiectasia. Exclusion criteria included known nonresponse to AzA, current or prior use (within 6 weeks of randomization) of noninvestigational products to treat rosacea, and presence of other dermatoses that could interfere with rosacea evaluation.
Participants were randomized into the AzA foam or vehicle group (1:1 ratio). The study medication (0.5 g) or vehicle foam was applied twice daily to the entire face until the end of treatment (EoT) at 12 weeks. Efficacy and safety parameters were evaluated at baseline and at 4, 8, and 12 weeks of treatment, and at a follow-up visit 4 weeks after EoT (week 16).
Results for the coprimary efficacy end points—therapeutic success rate according to investigator global assessment and nominal change in inflammatory lesion count—were previously reported,13 as well as secondary efficacy outcomes including change in inflammatory lesion count, therapeutic response rate, and change in erythema rating.14
Patient-Reported Secondary Efficacy Outcomes
The secondary PRO end points were patient-reported global assessment of treatment response (rated as excellent, good, fair, none, or worse), global assessment of tolerability (rated as excellent, good, acceptable despite minor irritation, less acceptable due to continuous irritation, not acceptable, or no opinion), and opinion on cosmetic acceptability and practicability of product use in areas adjacent to the hairline (rated as very good, good, satisfactory, poor, or no opinion).
Additionally, QOL was measured by 3 validated standardized PRO tools, including the Rosacea Quality of Life Index (RosaQOL),15 the EuroQOL 5-dimension 5-level questionnaire (EQ-5D-5L),16 and the Dermatology Life Quality Index (DLQI). The RosaQOL is a rosacea-specific instrument assessing 3 constructs: (1) symptom, (2) emotion, and (3) function. The EQ-5D-5L questionnaire measures overall health status and comprises 5 constructs: (1) mobility, (2) self-care, (3) usual activities, (4) pain/discomfort, and (5) anxiety/depression. The DLQI is a general, dermatology-oriented instrument categorized into 6 constructs: (1) symptoms and feelings, (2) daily activities, (3) leisure, (4) work and school, (5) personal relationships, and (6) treatment.
Statistical Analyses
Patient-reported outcomes were analyzed in an exploratory manner and evaluated at EoT relative to baseline. Self-reported global assessment of treatment response and change in RosaQOL, EQ-5D-5L, and DLQI scores between AzA foam and vehicle foam groups were evaluated using the Wilcoxon rank sum test. Categorical change in the number of participants achieving an increase of 5 or more points in overall DLQI score was evaluated using a χ2 test.
Safety
Safety was analyzed for all randomized patients who were dispensed any study medication. All analyses were performed using SAS version 9.2.