Evidence-Based Review: Fixed-Combination Therapy and Topical Retinoids in the Treatment of Acne

June 2011 | Volume 10 | Issue 6 | Original Article | 636 | Copyright © June 2011


Guy F. Webster MD PhD

Abstract
Topical fixed-combination products and topical retinoid monotherapy are established first-line treatments for mild-to-moderate acne vulgaris, yet adequate comparative data are lacking. The following evidence-based review addresses the question: "In patients with mild-to-moderate acne, are topical fixed-combination products or topical retinoids a more efficacious choice in reducing noninflammatory, inflammatory and total lesions after 12 weeks of treatment?" To identify relevant studies, a PubMed search was performed using "acne" and search terms for adapalene, tretinoin, tazarotene, benzoyl peroxide, clindamycin, or erythromycin. Forty-two studies from January 1991 to November 2009 were included. The studies were evaluated using the Strength of Recommendation Taxonomy, and all but seven received the highest level of evidence grade. To evaluate efficacy, a side-by-side comparison was made using reduction in acne lesion counts at week 12 for study groups treated with fixed-combination therapy or retinoid monotherapy. Twenty-nine studies containing relevant efficacy data for fixed-combination therapy and retinoid monotherapy are summarized here. Nine studies compared fixed-combination therapy with retinoid monotherapy; in eight of these studies, fixed-combination therapy was significantly more efficacious in reducing acne lesion counts. This evidence-based review analyzes clinical evidence to date for these therapies to provide guidance in determining appropriate treatment for patients with mild-to-moderate acne.

J Drugs Dermatol. 2011;10(6):636-644.
Acne vulgaris is common, affecting ≈70 percent of adolescents.1-4 Acne often begins with androgenic changes in puberty and persists into adulthood in about half the population.1,2 The underlying acne pathophysiology has been well studied, with four components affecting the pilosebaceous unit: (1) excess sebum production; (2) abnormal follicular desquamation; (3) proliferation of the commensal bacteria, Propionibacterium acnes (P. acnes); and (4) inflammation.5 This multifactorial process often requires multiple strategies for therapeutic intervention. Successful acne management is contingent upon various patient- and treatment-related factors. Compliance is a main patient-related barrier to acne treatment success, with patients described as fed up with, forgetful of, or too busy to adhere to treatment.6 Treatment-related barriers may include slower-than-expected or lack of efficacy, complexity of the prescribed treatment regimen, or overall tolerability — all potentially resulting in decreased treatment compliance.7 Successful acne management depends on selecting the most appropriate therapeutic regimen for an individual's acne profile.
Effective topical acne therapies include retinoids, antibiotics, benzoyl peroxide (BPO) and combination products. Clindamycin and erythromycin are bacteriostatic for P. acnes and reduce P. acnes-mediated inflammatory responses.8 Topical antibiotics (e.g., tetracycline) also have shown anti-inflammatory properties.8 BPO is comedolytic and bactericidal for P. acnes, impeding acne's inflammatory component.8,9 Retinoids (adapalene, tretinoin, tazarotene) have anti-inflammatory and comedolytic activity and modulate keratinocyte proliferation.9
The American Academy of Dermatology (AAD) published clinical guidelines and recommendations for management of acne vulgaris.10 Fixed-combination therapies (single products containing two antiacne medications) and topical retinoid monotherapy are standard first-line treatments. However, few head-to-head efficacy data compare fixed-combination products with retinoid monotherapy.
This systematic, evidence-based review evaluates the efficacy of fixed-combination therapies and retinoid monotherapy in