Dive Brief:

• Edgewise Therapeutics plans to meet with regulators in the U.S. and Europe to discuss how much clinical trial evidence it needs to seek expedited approval of its experimental drug for a form of muscular dystrophy known as Becker. 
• On Monday, the Colorado-based biotechnology company disclosed results from a Phase 2 study that showed its drug, called sevasemten, reduced levels of creatine kinase, an enzyme that’s associated with damage to skeletal muscles, by significantly more than placebo.
• The study was small and not designed to prove whether sevasemten also improves muscle function. Still, Edgewise said that secondary measures found a “trend toward improvement” on a scale widely used to assess motor abilities in people with muscular dystrophies like Becker or Duchenne. 

Dive Insight:

Edgewise’s data, and the regulatory possibilities they might unlock, were enough to send shares in the company higher by over 20% Monday, adding some $600 million in market value. 

Dubbed Canyon, the biotech’s trial enrolled 40 adults and 29 teenagers with Becker’s, an inherited condition that causes progressive muscle weakness. Its symptoms are considered to be more mild and variable than those of Duchenne, a related disease caused by different mutations in the same gene. Disruption in that gene affects the production and function of a protein called dystrophin, which protects muscle cells from damage due to repeated contraction and relaxation. 

Trial investigators measured changes from baseline in levels of creatine kinase, finding a 28% average decline between months six and 12 among study participants who received sevasemten versus those given placebo. However, Edgewise noted that adults in the drug arm of the study had more advanced disease at baseline than adults in the placebo group.

Secondary study measures included the motor function scale, known as NSAA, as well as tests of how quickly participants could walk and climb stairs. According to Edgewise, these measures all showed trends toward improvement for sevasemten, but given the study’s small size and statistical design these findings aren’t conclusive. 

No new safety concerns were reported and treatment was generally well tolerated, Edgewise said. 

Edgewise expects to complete enrollment in an expansion cohort, dubbed Grand Canyon, sometime between January and March. That study group will include 120 or so participants with Becker, and is powered to measure changes in NSAA at 18 months. If positive, the company expects this study data to support a marketing approval.

Edgewise plans to publish results from Canyon in a peer-reviewed medical journal.