Ganging up on acne: Clindamycin-benzoyl peroxide combination packs quick punch

Key Points

London - A new prescription acne product containing 1 percent clindamycin and 5 percent benzoyl peroxide (Duac Gel, Stiefel Laboratories) appears to be as effective as a gel containing 0.1 percent adapalene in reducing noninflammatory lesions, according to the author of a recent study.

"Many controversies surround benzoyl peroxide. Some dermatologists believe it has very little effect on comedogenesis," says Anthony Chu, M.D., professor of dermatology, Buckingham University, London, and consultant dermatologist, Hammersmith Hospital, London. Similarly, he says the bulk of medical literature on the topic labels benzoyl peroxide mildly comedogenic.

"If we look at the pathogenesis of acne," Dr. Chu says, "we know that comedones can be induced by inflammation, particularly interleukin (IL)-1. So, if one suppresses the inflammation, one may well be able reduce comedogenesis." However, he says no studies have carefully analyzed this possibility.

They wanted to see if these agents could produce comparable results in terms of inflammatory lesions, but - more importantly - to compare their anti-comedogenic effects, he tells Dermatology Times.

Study details

To that end, researchers enrolled 130 patients with mild-to-moderate acne vulgaris for a 12-week, single-blind, multicenter study in which patients applied one product or the other daily. For most patients, assessors counted lesions on the entire face - except the chin and nose - at baseline, then at weeks one, two, four, eight and 12 (unless patients discontinued treatment earlier).

For a few patients, assessors limited lesion counts to a specific area of the face. In these cases, they used the same area throughout the study.

Both products provided comparable efficacy and safety regarding inflammatory lesion counts (Langner A, Chu A, Goulden V, Ambroziak M. Br J Dermatol. 2008 Jan;158(1):122-129. Epub 2007 Nov 28).

As for noninflammatory lesion counts, investigators also noted progressive improvement versus baseline in all patient subgroups (male/female, teenager/adult, mild/moderate acne) for both products.

But, as with inflammatory lesions, Dr. Chu says that within each subgroup, BPO/C appeared to provide a faster time to response and a greater change from baseline at all time points compared to the adapalene cohort.

Among male patients, BPO/C produced a mean lesion count change of -8.2 percent at week one, and by week 12 this figure had risen to -56.9 percent. The corresponding percentages for adapalene were-2.3 and -24.8.

Among female patients, the mean percent change in lesion counts increased from -8.5 to -52.7 (week one to week 12) in the BPO/C group, versus -1.3 to -44.2 for adapalene.