MONDAY, May 15, 2006 (HealthDay News) -- Patients suffering from acne who are treated with a combination of antibiotics and topical gels may be able to keep their acne at bay using the gels alone, two new studies find.
"What both these studies show is that we can stop the antibiotic if patients are continued on a topical retinoid like adapalene or tazarotene," said Dr. Diane M. Thiboutot, of the Pennsylvania State University College of Medicine and the Milton S. Hershey Medical Center, who was involved in both studies. "This can change the way we treat acne."
Both reports appear in the May issue of the Archives of Dermatology.
Severe acne is a recurring disease often treated with a combination of oral antibiotics and topical medication. But because acne can return, so-called "maintenance" therapy is often necessary. However, due to reduced sensitivity of acne to certain antibiotics, some experts now recommend that antibiotics be used for only three months.
In the first study, Thiboutot's team looked at the efficacy of adapalene gel (brand name Differin) alone in maintaining the effects of successful acne treatment.
The study was funded by Galderma Laboratories, the makers of Differin.
Her group started with 253 patients with severe acne. The patients were treated with an antibiotic alone or with adapalene plus an antibiotic. They were then evaluated at the beginning of the study and at four, eight, 12 and 16 weeks.
"Once the acne improved and we were able to stop the antibiotic, the patients who were continued on adapalene really maintained the improvement in their acne that they had gotten from the combination of the antibiotic and adapalene," Thiboutot said.
Of patients who continued adapalene treatment, 75 percent maintained their treatment success compared with 54 percent of the patients who didn't use adapalene, the researchers found.
"If you continue to use adapalene, you can maintain the improvement you got from the use of the antibiotic," Thiboutot said. "This is important, because a lot of bacteria are becoming resistant to antibiotics, so we want to use antibiotics only when needed and only for as long as needed."
In the second study, researchers did a similar study using another gel, tazarotene. "This study also confirmed the same result," Thiboutot said.
In this study, headed up by Dr. James Leyden, of the Skin Study Center in Broomall, Penn., 90 patients with moderately severe to severe acne were treated with tazarotene (brand name Avage or Tazorac) and an antibiotic for up to 12 weeks.
Patients who showed improvement were then randomly assigned to 12 weeks of one of three maintenance regimens: tazarotene plus a placebo, unmedicated gel plus antibiotic capsules or tazarotene plus antibiotic capsules.
Leyden's team found that all three regimens were effective in maintaining acne improvement. After 12 weeks of therapy, average reductions in acne inflammatory and noninflammatory breakouts was 60 percent and 54 percent with tazarotene alone, 52 percent and 66 percent with antibiotic capsules alone, and 64 percent and 66 percent with tazarotene plus an antibiotic.
Over 24 weeks of treatment, more than 80 percent of patients in each group had sustained a 50 percent or greater improvement in their acne. "There really wasn't any difference between the three treatment regimens," Leyden said.
Leyden noted that most dermatologists continue prescribing an antibiotic. "What will be surprising for dermatologists is that you can maintain a very high percentage of patients on a topical medication alone," he said.
The study was funded by Allergan Inc., the makers of Tazorac.
Based on these findings, one expert said he would be more likely to take people off their antibiotics and try having them use topical medications alone once their acne was under control.
"It looks like topical medication alone may be effective by itself," said Dr. Steve Feldman, a professor of dermatology, pathology & public health sciences at Wake Forest University School of Medicine. "It would be reasonable to try to maintain patients without the long-term antibiotics," he added.
Feldman noted that if patients don't do well on a topical medication alone, they can be put back on an antibiotic. "Having people off antibiotics is better than having them on them, especially if they don't need then," he said. "But life's not a clinical study, you do what's best for the individual patient."
For more on acne, head to the U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases.