Efficacy and safety comparison of combination of 0.04% tretinoin microspheres plus 1% clindamycin versus their monotherapy in patients with acne vulgaris: a phase 3, randomized, double-blind study

Abstract

Background and objectives There is an unmet need for topical treatments with good tolerability in management of acne vulgaris. The present study aimed to evaluate efficacy and safety of a novel tretinoin (microsphere, 0.04%) formulation in combination with clindamycin (1%) gel for treatment of acne vulgaris. Materials and methods This phase 3 randomized, double-blind study included patients with moderate-to-severe acne. Patients were treated with tretinoin (microsphere, 0.04%) + clindamycin (1%) or one of the monotherapies (tretinoin, 0.025%; clindamycin, 1%). Key endpoints included percent change in lesion counts, and improvement in Investigator’s Static Global Assessment (ISGA) score. Results 750 patients were randomized (combination, n = 300; tretinoin and clindamycin, each n = 150). At week 12, reductions in inflammatory (77%), non-inflammatory (71%) and total lesions (73%) were significantly greater with combination treatment versus either monotherapy (p < .03). Proportion of patients rated ‘clear’ or ‘almost clear’ with ≥2-grade ISGA improvement was higher with combination (46%) versus monotherapies (p < .02). Adverse events occurred in 20 patients, most were mild-moderate; no deaths or serious adverse events were reported. The discontinuation rates due to adverse events with combination therapy were low (≤1%). Conclusion The once-daily, microsphere-based formulation was generally tolerable with a positive impact on therapeutic outcomes and patients’ compliance. ClinicalTrial Registration No. CTRI/2014/08/004830

Keywords

• acne vulgaris
• tretinoin
• clindamycin
• microspheres