Total of 210 patients were enrolled across 16 investigative sites in the United States, randomly assigned to tazarotene 0.045% lotion (N=69), tazarotene 0.1% cream (N=72), or vehicle (N=69) and included in the ITT analysis, see Figure 1. Patients were treated with vehicle lotion (N=34) or vehicle cream (N=35) to ensure blinding, however vehicle results are combined in these analyses. Overall, 189 patients (90%) completed the study, including 65 patients (94.2%) on tazarotene 0.045% lotion, 63 patients (87.5%) on tazarotene 0.1% cream, 61 patients (88.4%) on combined vehicle. The most common reasons for study discontinuation were ‘lost to follow-up (N=12)’ or ‘subject request (N=5)’. One patient treated with tazarotene 0.1% cream discontinued due to adverse event. Four patients were excluded from the safety population due to no post-baseline safety assessment.
Demographic data (Table 1) was similar across the treatment groups. The mean age was 21.2 to 23.3 years. There was a slightly higher proportion of female patients overall (55.2%); 61.4% were Caucasian, with 28.6% Black or African American. There were no noticeable differences between treatment groups in regard to baseline lesion counts, or EGSS. At baseline, the mean number of inflammatory and noninflammatory lesions ranged from 27.2 to 28.3 and 36.6 to 37.6, respectively. At baseline, 92.4% of patients had moderate acne (EGSS=3).
Tazarotene 0.045% lotion resulted in statistically significant reductions in both inflammatory and noninflammatory lesion reductions compared to combined vehicle at week 12. Mean percentage change from baseline to week 12 in inflammatory lesion counts was 63.8% versus 51.4% with the combined vehicle (P=.006), and in noninflammatory lesion counts 56.9% versus 35.2% with vehicle (P<.001), see Figures 2 and 3. Tazarotene 0.045% lotion showed a greater reduction from baseline to week 12 in inflammatory and noninflammatory lesions when compared with tazarotene 0.1% cream, but differences were not significant (P=.680 and .612).
Median percent change from baseline to week 12 in inflammatory and noninflammatory lesion counts with tazarotene 0.045% lotion was 72.4% and 62.5% versus 66.7% and 56.4% with tazarotene 0.1% cream and 60.0% and 42.3% with vehicle, respectively.