FDA Grants Orphan Drug Designation to Cytokinetics Therapy CK-2127107 for Spinal Muscle Atrophy

The U.S. Food and Drug Administration (FDA) has granted Cytokinetics’ investigational spinal muscular atrophy (SMA) treatment CK-2127107 Orphan Drug Designation. That gives it seven years of U.S. marketing exclusivity, tax credits for clinical research and a waiver from FDA user fees.

CK-2127107, developed in partnership with Astellas Pharma, is a next-generation fast skeletal muscle troponin activator. The compound acts to slow the release of calcium inside muscle fibers. Calcium is a signaling factor in muscle, telling proteins to start or stop contracting a muscle. By lowering calcium levels, CK-2127107’s developers hope the mechanism will become more sensitive to calcium, improving contractile ability.

Researchers have shown that the drug causes SMA mice to improve, and the treatment is now in a Phase 2 trial (NCT02644668) in SMA. The trial — which will test two doses of the drug compared to placebo — recently started recruiting patients to the higher-dose group.

“We are pleased that the FDA has granted orphan drug status to CK-2127107 for the potential treatment of patients with SMA, one of the most common potentially fatal genetic disorders due to progressive neuromuscular weakness resulting in severe respiratory and ambulatory impairment,” Fady I. Malik, executive vice-president and head of research and development at Cytokinetics, said in a press release.

“We are exploring the potential of CK-2127107 to improve muscle function and physical performance in patients with SMA and we look forward to seeing results from our ongoing Phase 2 clinical trial later this year,” added Malik.

CK-2127107 is also being developed to potentially treat other conditions. The San Francisco-based company will explore the drug in a Phase 1b study (NCT03065959), aiming to reduce muscle fatigue among elderly patients with movement problems. In addition, a Phase 2 study (NCT02662582) in patients with chronic obstructive pulmonary disease will investigate whether CK-2127107 can reduce exercise intolerance and improve physical capacity.