Novartis has landed a coveted breakthrough therapy designation from the U.S. Food and Drug Administration for a mid-stage orphan drug targeting a rare, yet potentially life-threatening, muscle-wasting condition.

If approved, bimagrumab could be the first treatment for patients with sporadic inclusion body myositis and the third breakthrough designation for Novartis. The company has also won the designation for an acute heart failure drug and a therapy for a certain variation of non–small cell lung cancer.

The FDA’s Center for Drug Evaluation and Research has granted just about one third of the 77 requests for its breakthrough designation in fiscal 2013. Of the 25 requests granted, just 18 have been publicly announced, according to a list of breakthrough designations compiled by The Burrill Report.

The breakthrough designation for the Novartis’ bimagrumab was based on a proof-of-concept study that showed the fully human monoclonal antibody substantially benefited patients with the progressive muscle-weakening disease compared to a placebo. The designation will help expedite the drug’s development through its included intensive FDA guidance and a fast-tracked review.

Results of the qualifying study will be presented at the American Neurological Association meeting on October 14 and published later this year, Novartis says.

Novartis Institutes for Biomedical Research developed bimagrumab in collaboration with Morphosys, which used its Human Combinatorial Antibody Library to identify the antibody. The experimental therapy stimulates muscle growth by blocking signaling from molecules that would otherwise inhibit that growth and lead patients’ muscles to atrophy.

In addition to sporadic inclusion body myositis, Novartis is developing bimagrumab for chronic obstructive pulmonary disease, cancer cachexia, sarcopenia, and in mechanically ventilated patients.