Microencapsulated Benzoyl Peroxide and Tretinoin for the Treatment of Acne Vulgaris: Results from a Phase 2 Multicenter, Double-Blind, Randomized, Vehicle-Controlled Study.

This phase 2, 12-week, multicenter, randomized, double-blind, active- and vehicle-controlled (VC), parallel-group trial assessed the efficacy and safety of silica encapsulated benzoyl peroxide BP (E-BP), two concentrations of silica encapsulated tretinoin (E-ATRA) and their combinations (TWIN high and low) vs VC in 726 males and females ≥9 years of age with moderate-to-severe inflammatory facial acne. The co-primary efficacy endpoints were Investigators Global Assessment (IGA) success rate ("clear" or "almost clear") and changes from baseline in inflammatory and non-inflammatory lesion counts. TWIN high and low were each significantly superior vs VC for IGA success at 12 weeks (39.7% and 27.4%, respectively, vs 12.3%, P < 0.001 and P < 0.01). TWIN high and low resulted in mean reductions in inflammatory lesions of -16.9 (64%) and -17.0 (60.8%) vs -11.5 (42%) for VC. Reductions in non-inflammatory lesions were -23.7 for TWIN low (54.9%) and -23.6 for TWIN high (53.3%) vs -13.7 (32.4%) for VC (all P < 0.001 vs VC). Results for TWIN were also numerically superior to E-BP and E-ATRA. All treatments were safe with comparable skin tolerability. The significant superiority of both combinations over VC and numerical superiority over E-BP and E-ATRA were achieved without an increase in adverse events or reduced skin tolerability.