Evidence Backs Some Drugs for Hidradenitis Suppurativa
EXPERT OPINION FROM THE ANNUAL CONGRESS OF THE EUROPEAN ACADEMY OF DERMATOLOGY AND VENEREOLOGY
PRAGUE – A handful of drugs are backed by solid-quality evidence for the treatment of hidradenitis suppurativa, although to date no form of therapy is approved for this indication.
Topping the list are the tumor necrosis factor (TNF)-alpha inhibitors. They have a plausible mechanism of benefit in hidradenitis suppurativa (HS). They’ve also demonstrated effectiveness for this common inflammatory skin disease in randomized, placebo-controlled clinical trials, Dr. Gregor B. Jemec said at the annual congress of the European Academy of Dermatology and Venereology.
In addition, one older randomized trial suggests that topical clindamycin is effective, mainly in milder cases. The most promising antibiotic regimen, consisting of oral clindamycin at 300 mg twice daily plus rifampicin at 600 mg daily, has not been studied in a randomized trial. But several large, rigorous case series have demonstrated "dramatic improvement" in response to the combination, according to Dr. Jemec of the University of Copenhagen.
The discovery that anti-TNF therapy is effective for HS was a serendipitous finding that occurred when physicians noted marked improvement in the skin disease in a patient taking infliximab for Crohn’s disease. The biologic plausibility of the observed benefit is underscored by the fact that TNF levels are actually more elevated in patients with HS than in those with psoriasis, Dr. Jemec said.
Infliximab missed its primary efficacy end point of clear or almost clear in a 38-patient randomized trial, but it did hit several clinically important secondary end points, including pain reduction and improved quality of life (J. Am. Acad. Dermatol. 2010;62:205-17).
On the other hand, etanercept showed no benefit in a 20-patient pilot randomized trial (Arch. Dermatol. 2010;146:501-4).
By far the best studied TNF inhibitor in HS is adalimumab (Humira). It is the subject of two ongoing, pivotal phase III randomized, double-blind, placebo-controlled, multinational clinical trials aimed at winning adalimumab regulatory approval as the first-ever drug indicated for the treatment of HS.
Last year, Dr. Alexa B. Kimball of Harvard Medical School, Boston, presented the primary end point of a 16-week, randomized, double-blind phase II clinical trial involving 154 patients with HS who were placed on adalimumab 40 mg weekly, adalimumab 40 mg every other week, or placebo. At week 16, a Physician Global Assessment of clear, minimal, or mild disease with at least a 2-grade improvement over baseline was documented in 23.5% of patients on placebo, 21.2% of those on alternate-week adalimumab, and 49% of those on adalimumab 40 mg every week.