Treating keloids: Etanercept demonstrates therapeutic effect

June 1, 2008

In the first study of intralesional etanercept as a treatment for keloids, the drug shows early promise, particularly regarding pruritus, says a study author.

Key Points

National report - A small study has shown for the first time that intralesional etanercept may provide an effective treatment for keloids, one of the authors says.

Because there is currently no consistently effective treatment for keloids, investigators tested an intralesional corticosteroid (triamcinolone acetonide/TAC) against intralesional etanercept (Enbrel, Amgen/Wyeth), says Martha Viera, M.D., clinical research fellow, department of dermatology and cutaneous surgery, University of Miami School of Medicine.

A mainstay of keloid treatment, intralesional corticosteroids downregulate collagen gene expression, alter glycosaminoglycans and decrease fibroblast proliferation.

The recombinant TNF-alpha receptor fusion protein etanercept is capable of binding to and neutralizing activity of soluble TNF-alpha, thereby reducing local TNF-alpha activity in abnormally dense fibrous tissue such as keloids, she says.

Therefore, etanercept may have an anti-fibrotic therapeutic effect, she says.

Study parameters

For the single-center, prospective, single-blind, IRB-approved study, investigators randomized 20 subjects, who were treated with either 25 mg/ml of etanercept or 20 mg/ml of TAC injections monthly for two months.

Investigators evaluated keloids at baseline, week four and week eight using a visual analog scale (VAS, 0=best, 10=worst) in a blinded fashion.

Researchers also digitally photographed keloids and noted adverse events during each visit.

All 10 subjects in the treatment cohort completed the study; eight in the control group did so as well.

Results

At week four, etanercept achieved greater improvements than TAC on parameters including erythema and pruritus. However, these findings did not reach statistical significance.

At week eight, etanercept achieved a considerable improvement on four out of 12 parameters (induration, erythema, itching, patient cosmetic assessments), Dr. Viera says, although none of these findings reached statistical significance.

"It was interesting to find that etanercept reduced pruritus more significantly than TAC did (-56 percent versus -23 percent at week eight)," Dr. Viera says.

"Since steroids are drugs that produce an anti-inflammatory effect," she says, "one would expect to find less pruritus after a course of treatment with steroids."

Regarding patient satisfaction, etanercept scored 46.1 percent at week four and 56.2 percent at week eight. TAC, on the other hand, earned patient satisfaction scores of 61.3 and 62 percent, respectively.

Limitations

The study's limitations include small size and short-term follow-up, as well as the fact that patients only received two doses, Dr. Viera says.

"During this study," she says, "the available etanercept concentration was limited to 25 mg/ml. Therefore, additional studies with higher concentrations (50 mg/ml) and larger study populations would be needed to assess etanercept's efficacy and tolerability and to determine its potential use in the treatment of keloids."

Strengths

"Keloids are difficult to treat. Etanercept, at the administered intralesional dose, was safe and well-tolerated and obtained improvement in several parameters measured in keloids," Dr. Viera says.

"This is a totally new therapeutic application of an anti-TNF-alpha drug, which has never been tried before," she says.

Disclosure: This study was partially sponsored by Amgen. Dr. Viera reports no other relevant financial interests.

For more information: http://www.aad.org/ http://www.med.miami.edu/