Novel tretinoin 0.05% lotion for the once-daily treatment of moderate-to-severe acne vulgaris: assessment of safety and tolerability in subgroups.

Background: Topical tretinoin's role in acne has been established through evidence-based guidelines. Cutaneous irritation and potential to cause or exacerbate postinflammatory hyperpigmentation (PIH) may limit use.Objective: Evaluate safety and tolerability of novel polymeric formulation of tretinoin 0.05% lotion in moderate-to-severe acne.Methods: One thousand six hundred and forty patients randomized to tretinoin 0.05% lotion or vehicle in two double-blind placebo-controlled 12-week studies. Investigator-evaluated cutaneous safety (erythema and scaling) and patient-reported tolerability (itching, burning/stinging) assessed using a scale of 0 (none) to 3 (severe). Hyper- and hypo-pigmentation evaluated at each study visit. A number of subpopulations were investigated.Results: Tretinoin 0.05% lotion was considered safe and very well tolerated. Only application site pain (3.1%), dryness (3.7%) and erythema (1.4%) were reported by >1% or patients. Treatment-related adverse events were particularly rare (≤2%) in Hispanic and male subpopulations, and lower in adult females. The severity of cutaneous safety and tolerability scores remained <0.5 (where 1 = mild) and were generally lower than baseline severity. Tretinoin 0.05% lotion did not appear to cause or exacerbate PIH.Conclusions: A novel polymeric formulation of tretinoin 0.05% lotion provides a highly favorable safety and tolerability profile, with an incidence of erythema, dryness, and skin burning lower than that previously reported with other formulations of tretinoin.