'Real-world' acne study documents benefits of retinoid-based combotx

June 1, 2006

At study completion, about two-thirds of patients were rated asachieving "success," defined by a 50 percent or greater reductionin lesion counts.

National report - Results of a "real-world," phase 4 study involving nearly 2,000 patients treated by more than 400 U.S. dermatologists demonstrate that the topical retinoid adapalene gel 0.1 percent (Differin, Galderma) dramatically improves acne in patients with moderate to moderately severe disease when it is started in combination with or added to other treatments, reports Linda Stein Gold, M.D.

All patients used adapalene 0.1 percent gel once nightly in combination with one or more other oral or topical agents. About three-fourths of the participants started de novo treatment for their acne, and the rest received adapalene as add-on therapy.

At study completion, about two-thirds of patients were rated as achieving "success," defined by a 50 percent or greater reduction in lesion counts, while in the Investigator Global Assessment, about 30 percent achieved clear or almost clear ratings, and another 30 percent were markedly improved.

"This study is noteworthy both as one of the largest prospective dermatology studies ever undertaken and because it provides real-world information about acne management and patient response. The improvements achieved were very consistent with those reported in previous combination studies, and so it was encouraging to see that the positive outcomes occurring in the context of rigorously conducted clinical trials are attainable in the setting of daily community practice," Dr. Stein Gold says.

"Moreover, these data provide important evidence to support the recommendation advocating combination therapy that was issued several years ago by the Global Alliance to Improve Outcomes on Acne."

The study participants were mostly females (63.5 percent) and predominantly white (71 percent). Sixty percent were in the 12- to 20-year-old age range, and about three-fourths had moderate acne.

Response hastened

The efficacy assessments showed that at week six, 90 percent of patients had achieved some improvement and total lesion counts were reduced 50 percent on average. At week 12, total lesion counts had dropped by 70 percent and there were similar decreases in noninflammatory and inflammatory lesion counts.

"These data indicate combination therapy has a benefit for hastening acne responses. Improvements seen at six weeks in this study are similar to those achieved at 12 weeks in the FDA clinical trials of topical retinoid monotherapy, but in MORE, further improvement occurred as treatment continued to 12 weeks," Dr. Stein Gold says.

When the results were analyzed by whether patients were newly started on acne treatment or received adapalene as add-on therapy, response rates were similar in those two groups.

"It seems that some patients may already be receiving combination treatment for their acne but have reached a plateau in their response. According to this study, adding topical adapalene in that situation may provide an effective jumpstart toward significant further improvement," Dr. Stein Gold says.

The benefits of combination therapy were achieved without significant safety or tolerability issues. Only 1.2 percent of patients withdrew because of an adverse event, and investigator ratings showed that relatively few patients (1.5 percent to 4.6 percent) had moderate or worse erythema, peeling/scaling, dryness or stinging/burning reactions at weeks six and 12.