Statistical analyses were conducted using SAS® software, version 9.3 or later. AEs were classified using the Medical Dictionary for Regulatory Activities (MedDRA) terminology for the safety population.
In this pooled analysis, a total of 1614 patients were randomized to tazarotene 0.045% lotion (n=799) or tazarotene lotion vehicle (n=815; Figure 1). Of these, 692 (86.6%) and 722 (88.6%) completed the study, respectively. The most common reasons for study discontinuation were lost to follow up (45, 5.6%) and patient request (34, 4.3%) in the tazarotene 0.045% lotion arm, and lost to follow up (56, 6.9%) and patient request (23, 2.8%) in the vehicle arm. AEs led to study discontinuation in 19 (2.4%) and 4 (0.5%) of patients in the tazarotene and vehicle arms, respectively. The safety population consisted of 1570 patients (tazarotene n=779; vehicle n=791), with 44 patients not included due to lack of any post-baseline safety evaluation.
Patient demographics and disease characteristics at baseline are shown in Table 1 and baseline QoL scores in Table 2. Characteristics were well matched between the two arms. The mean age overall was 20.5 years (standard deviation [SD] 6.9) and the majority of patients (65.9%) were female. All patients had moderate (EGSS 3) or severe (EGSS 4) disease, the latter comprising 9.1% and 9.1% of the tazarotene and vehicle arms, respectively.
Significantly more patients in the tazarotene 0.045% arm than in the vehicle arm achieved the co-primary endpoint of treatment success, defined as achieving at least a 2-grade improvement in EGSS with a final score of clear or almost clear (30.4% vs 17.9%, P<0.001; Figure 2).
Tazarotene 0.045% lotion was associated with significant reductions in inflammatory lesion counts (Figure 3) as well as noninflammatory lesion counts (Figure 4) compared with vehicle. Mean inflammatory lesion counts were reduced 57.9% and 47.8% in the tazarotene and vehicle arms, respectively (P<0.001) at week 12; significant differences between tazarotene and vehicle were observed by week 8 (Figure 3). Significant reductions in noninflammatory lesion counts were observed as early as week 4 (32.6% vs 24.2%; P<0.001) and were further reduced at week 8 (46.6% vs 33.6%; P<0.001) and week 12 (56.0% vs 42.0%; P<0.001; Figure 4).
Improvements in Acne-Specific QoL scores at week 12 were numerically greater for the tazarotene 0.045% cohort versus vehicle in all 4 domains (self-perception: 7.5 vs 6.7; role emotional: 6.0 vs 5.5; role-social: 4.7 vs 4.1; acne symptoms: 6.4 vs 5.3; Table 2).
Safety results for the pooled studies have been reported.22 Treatment-emergent AEs (TEAEs) were reported by 209 patients