BioWorld International Correspondent

ZICHRON YA'AKOV, Israel - Ester Neurosciences Ltd. said the FDA has granted the company orphan drug designation for Monarsen, the company's first product from its antisense platform.

Patient recruitment for a one-month clinical trial now is under way. The orally administered Monarsen treatment for myasthenia gravis (MG) showed for the first time that an antisense therapy for a neurological disease could be given by mouth.

The results of the Phase Ib trial of Monarsen (previously known as EN101) were presented at the annual meeting of the National Academy of Neurology earlier in the year in Honolulu, Hawaii.

Sixteen patients showed significant behavioral improvements with no cholinergic side effects or other significant adverse events. Fourteen of 16 patients had 27.8 percent to 53.4 percent improved quantitative myasthenia gravis scale scores on the last day of four days of dosing, compared to baseline.

Eli Hazum, Ester's CEO, told BioWorld International that the superior efficacy, longer duration of action and a more favorable side effect profile than currently used medications appears to have impressed the FDA.

Hazum also said, "Orphan drug designation gives Ester exclusive marketing rights in the U.S. for seven years upon drug approval, additional eligibility for clinical research grants, tax benefits and exemptions from certain NDA application fees.

"Obtaining orphan drug designation marks an important step in our regulatory strategy for Monarsen," he added. "Current MG treatments, including anticholinesterases, steroids and immunosuppressants, offer limited efficacy and often cause unpleasant and sometimes dangerous side effects. Monarsen offers the prospect of an efficacious and safe product that can address a $300 million market."

Monarsen is based on the research of Hermona Soreq, who heads the department of life sciences at the Hebrew University of Jerusalem and serves as Ester's chief scientific adviser.