Alan Shalita, M.D., Ph.D., a leader in acne research, has studied the condition for more than 30 years.
Dr. Shalita's first paper published in the dermatology literature described inhibition of lipase production by subminimal inhibitory concentrations of tetracycline and other antibiotics, which was the earliest suggestion that those drugs used in acne management offered anti-inflammatory activity. During the 30-plus years of his dermatology career, he has participated as an investigator in nearly all pivotal clinical trials leading to the approval of new acne treatments. He is a frequent lecturer on this topic, most recently serving as director for a forum on "Retinoids in Acne Treatment" at the annual meeting of the American Academy of Dermatology.
Dr. Shalita participated in the Global Alliance to Improve Outcomes in Acne and was a co-author of that panel's report [J Amer Acad Dermatol 2003;49(Suppl 1):S1-S37].
An international group of dermatologists gathered together thanks to funding from an unrestricted educational grant from Galderma. We reviewed and discussed the published literature and took into account expert opinion to develop consensus recommendations regarding the role of different acne treatments, along with a treatment algorithm based on acne severity and lesion type.
Q How do these guidelines differ from the previous guidelines?
The report issued by our group probably provides more specific recommendations on the management of different forms of acne. In addition, it emphasizes the use of topical retinoids as first-line therapy alone or in combination with other agents for all forms of acne except the most severe disease with nodular/conglobate lesions.
The new consensus reflects a more recent rediscovery of the efficacy of topical retinoids in the management of inflammatory acne. Overall, the recommendations are not a major departure from the content of the Academy guidelines because information about most of the modalities in use has been well accepted for some time.
Results from the original clinical trials [indicated that] tretinoin (Retin-A, Ortho), the first available topical retinoid, was clearly effective for reducing inflammatory lesion counts as well as comedones, and its benefit on inflammatory lesions is not unexpected considering that the microcomedo is the precursor of all acne lesions. However, because the early tretinoin formulations were quite irritating, a tendency emerged among dermatologists to avoid topical retinoid treatment for inflammatory disease. More recently, data from the clinical trials of adapalene (Differin, Galderma) and tazarotene (Tazorac, Allergan) served as a reminder about the efficacy of topical retinoids for treating inflammatory as well as comedonal acne.
Q Why is combination therapy with topical retinoids and an antibiotic important for treating most forms of acne?
Acne is a multifactorial disease, and because this dual regimen addresses more than one factor in the pathogenesis, it allows for a faster and more complete response. The topical retinoid prevents formation of the microcomedo, which is the precursor lesion to both mature comedones and inflammatory lesions. There is also evidence that some of the topical retinoids have anti-inflammatory properties. The antimicrobial agent specifically targets Propionibacterium, which is involved in the development of inflammatory acne through its ability to trigger an inflammatory response, and the topical retinoid may even enhance the activity of a topical antibiotic by increasing its penetration into the follicular canal both by promoting exfoliation at the skin surface and increasing turnover of the follicular epithelial cells.