New developments in topical antimicrobial therapy for acne.

Benzoyl peroxide (BPO) has been an important component of the acne treatment armamentarium for decades. A number of characteristics contribute to its success in acne, including its lipophilicity, potent antibacterial activity, and ability to suppress antibiotic-resistant strains of Propionibacterium acnes. With some commercially available products in which BPO comprises crystals in suspension, aggregation of BPO can occur on the skin surface in large clumps, resulting in poor penetration of sebaceous follicles. In addition, the poor water solubility of BPO, coupled with its chemical instability in other solvents, presents challenges with respect to formulating topical products with optimal bioavailability, stability, and tolerability. Several products and vehicle systems have evolved in attempts to improve on the benefits of BPO in treating acne. A new acne treatment has been developed that contains 5% solubilized BPO consisting of small-size particles. This new product exhibits enhanced follicular penetration of BPO, improved P acnes kill rates and clinical efficacy, and good consumer acceptance relative to existing formulations.