Once acne is under control, the goal is to keep skin clear. Exactly how to do that is the topic of two studies and an editorial in the Archives of Dermatology.
About the Studies
Both studies involved patients with acne vulgaris, a very common type of acne. The studies tested retinoid gels as maintenance therapy in acne patients.
All of the patients in both studies had already reduced their acne considerably through prescription treatment that included an oral antibiotic. The researchers wanted to see if it was possible to maintain those benefits after patients were no longer taking oral antibiotics.
The Differin study was funded by Galderma, Differin's maker. The Tazorac study was funded by Allergan Inc., Tazorac's maker. In the journal, various researchers from both studies report connections with drug companies including Galderma and Allergan Inc.
The Differin study included 253 people who had had severe acne. Their acne had been at least halved while taking an oral antibiotic (doxycycline) and either Differin or a similar gel lacking any medicine (placebo) for 12 weeks.
Patients in the Differin study either used Differin or a placebo gel for 16 weeks, without taking oral drugs. Three-quarters the people in the Differin group maintained their clearer skin, compared with a little more than half of those using the placebo gel (54%).
"This study demonstrates a clinical benefit of continued treatment with adapalene gel, 0.1%, as a maintenance therapy for acne," write the researchers, who included Diane Thiboutot, MD, of Pennsylvania State University's medical school.
Thiboutot also worked on the Tazorac study, along with experts including James Leyden, MD, of the Skin Study Center in Broomall, Pa.
The Tazorac study included about 90 patients who had had moderately severe to severe minocycline and applied a pea-sized amount of Tazorac gel to their faces every morning and evening.. Those patients had already taken the oral antibiotic
As a result, the patients had cut their acne by at least 75%.
Next, the researchers assigned patients to one of three maintenance treatments:
- Tazorac gel with pills lacking any medicine (placebo)
- Placebo gel with minocycline pills
- Tazorac gel with minocycline pills
Twelve weeks later, the researchers checked the patients' skin. "All regimens were effective in sustaining improvements in acne," Leyden and colleagues write.
What Does 'Maintenance' Mean?
The journal editorial -- and the studies -- point out that "maintenance" hasn't been officially defined in acne treatment. Without an agreed-upon benchmark, it can be hard to gauge success.
Future studies should test benzoyl peroxide skin treatments (which are less costly than retinoids) for maintenance therapy, writes editorialist Lee Zane, MD, MAS. Zane works in the dermatology department of the University of California, San Francisco.
As for the Differin and Tazorac studies, Zane's editorial states that "although admittedly not definitive, these studies offer promising data for the role of retinoids in acne maintenance therapy, and they invite us to give careful consideration to how such therapy should be studied in the future."
In his editorial, Zane writes that it is "truly a step in the right direction" to be looking for therapeutic options to long-term antibiotic therapy for acne patients.
The most common adverse side effects reported for the gels included itching for the Differin study and burning, peeling, and redness for the Tazorac study.