Investigational Drug May Treat Rare Skin Condition

An experimental therapy for dermatomyositis (DM)—a rare dermatological condition—was found to reduce symptoms among patients who were resistant to other therapies, according to a study presented at the American College of Rheumatology/Association of Rheumatology Health Professionals

Annual Meeting.

DM is an inflammatory skin condition characterized by a rash and can be linked to muscle weakness. While some patients only experience skin symptoms, patients can also experience fevers, shortness of breath, weight loss, and light sensitivity.

Currently, less than 100,000 patients in the United States have the condition. Treatment options are limited and include immunosuppressants, which can be ineffective for some patients, according to the study.

"Not only are current treatments limited, but this disease itself is very understudied, so we've had to build our understanding of DM from the ground up just to be in a position to run a trial like this," said principal investigator Victoria P. Werth, MD.

A significant challenge the study authors faced was developing a system to measure the severity of the condition. With psoriasis and other skin conditions, physicians measure the amount of skin affected, but this is not accurate for patients with DM, according to the authors.

"In DM, body surface area is less informative, because even though you may only have DM on a small percentage of your skin, it can still have severe effects," Werth said. "We needed a way to look for the amount of disease in a given area."

To address this, the team developed the Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI), which measures skin severity as separate activity and damage scores. The authors noted that a higher score correlates to a more severe condition.

The authors have validated CDASI over the past decade through many studies, but this was the first placebo-controlled randomized clinical trial that uses the metric to assess a novel drug, according to the study.

Included in the clinical trial were 22 patients with skin-predominant DM who had CDASI scores ranging from 33 to 35, which is classified as severe. All patients previously failed to respond to standard treatments.

Patients were randomized to receive anabasum 20-mg once per day or a placebo. After 1 month of treatment, patients received 2 daily doses of anabasum.

The authors discovered that patients who received the drug were observed to have less severe disease. These patients reported a better quality of life and improved symptoms, according to the study.

The authors also found that patients treated with anabasum had a mean decrease in CDASI score of at least 6 points compared with placebo, according to the study.

Common side effects included diarrhea, dizziness, fatigue, and dry mouth. No patients discontinued using the drugs as a result of the side effects, according to the authors.

The authors are continuing to study the safety and efficacy of anabasum in 20 of the patients with DM in a long-term extension clinical trial.

Based on the results from the phase 1 trial, the authors concluded there is a need for additional clinical trials that include more patients with DM.