By Natalie Huet and Ransdell Pierson
PARIS/NEW YORK, July 9 (Reuters) - An experimental drug from Sanofi and Regeneron Pharmaceuticals Inc significantly reduced skin lesions and itching in adult patients with atopic dermatitis, a chronic form of eczema that is poorly controlled by standard drugs, the companies said on Wednesday.
The findings were seen in a Phase IIb, or mid-stage, trial of the injectable drug dupilumab, which is also being tested by the drugmakers against two other allergic conditions: asthma and nasal polyps.
Dupilumab was named "clinical advance of the year" in 2013 by industry publication Scrip Intelligence, and some analysts expect it to capture annual sales up to $2 billion if approved.
Atopic dermatitis causes patches of dry, red and highly itchy skin on any part of the body. Patients, many of whom also have asthma and hay fever, have compared the sensation to having unending poison ivy.
Currently, patients get limited relief from topical steroid creams and oral steroid medicines that are not approved in the United States for the condition.
Dupilumab works through a new approach, by blocking two proteins linked to inflammation, interleukin-4 (IL-4) and interleukin-13 (IL-13).
The 16-week Phase IIb clinical trial involved 380 adults with moderate to severe atopic dermatitis, and about half their skin was affected by the disease. All doses of dupilumab met the study's main goal, showing greater improvement of eczema symptoms compared to placebo.
Improvement rates ranged from 74 percent for patients on the highest dose (300 mg weekly) to 45 percent in those with the weakest dose (100 mg monthly), as judged by a standard index that evaluates area and severity of eczema. That compared with an 18 percent improvement in patients given a placebo.
"It's really the itch associated with atopic dermatitis that can affect your quality of life, your employment and ability to function and to go to school and to sleep," George Yancopoulos, Regeneron's research chief, said in an interview.
Dupilumab, if approved, would likely be the first drug to directly target proteins that cause the disease, Yancopoulos said.
In separate Phase IIa trial results published last year, dupilumab slashed asthma episodes by 87 percent, making it a potential game changer for patients with moderate to severe disease.
The most common side effects of the drug include nasopharyngitis (common cold) and headache.
Sanofi and Regeneron expect to begin late-stage trials of dupilumab in atopic dermatitis later this year.
The New England Journal of Medicine on Wednesday published favorable data from earlier studies of dupilumab in atopic dermatitis.
Dr. Lisa Beck, a professor of dermatology at Rochester Medical Center who helped conduct those trials, said about 3.4 million U.S. adults have moderate to severe atopic dermatitis.
"We will get a surge of eczema patients seeking treatment with this drug" if it is approved, she predicted.
(Reporting by Natalie Huet and Ransdell Pierson; Editing by Cynthia Osterman)