Sitris drug enters new phase

Sirtris Pharmaceuticals Inc. of Cambridge announced today the initiation of a Phase 1b clinical trial of a drug candidate for patients with MELAS syndrome.

MELAS is a progressive and fatal disorder caused by a mutation in the DNA, the company said.

There are currently no known treatments for the disease, and it is so rare that Sirtris believes that there may be "an orphan drug opportunity" for the company.

Sirtris drug candidate, known as SRT501, is being studied in patients with MELAS, and it is also being evaluated in clinical trials in patients with Type 2 diabetes.

In the United States, the Orphan Drug Act rewards companies that develop drugs for rare diseases by giving them seven years to sell each new treatment without competition from other manufacturers.
(By Chris Reidy, Globe staff)