Antisense Therapeutics chief executive Mark Diamond says the Melbourne biotech has hit a “very significant commercial milestone” after US regulators granted orphan drug designation for its possible treatment for a rare fatal wasting disease.

The United States Food and Drug Administration granted the designation for Antisense’s drug ATL1102 for the treatment of Duchenne muscular dystrophy (DMD), Antisense announced on Monday.

The designation is meant to encourage treatments for rare diseases that affect fewer than 200,000 people in the United States, and it can include tax credits towards the cost of clinical trials, waiver of US prescription drug filing fees and seven years of product exclusivity from generic competition.

“The orphan drug designation is a very significant commercial milestone for the company,” Antisense chief executive Mark Diamond said.

“This FDA recognition spotlights the significant unmet need for patients living with DMD and ATL1102’s potential to markedly improve the quality of life of those boys so desperate for an effective treatment.”

The FDA gave Antisense a rare pediatric disease designation last month, which makes the treatment eligible for a regulatory voucher that could be traded on secondary markets for  hundreds of millions of dollars.

Antisense says that ATL1102 could have a “profound” impact on boys with DMD, in slowing the muscle wasting associated with the disease. A phase 2b study is planned for next year..