The FDA found that data from a single Phase II study were “insufficient” to justify an accelerated approval review for sevasemten in Becker muscular dystrophy.
The FDA has declined to consider Edgewise Therapeutics’ investigational skeletal myosin blocker sevasemten for accelerated approval for the treatment of Becker muscular dystrophy.
Stifel analysts appear unsurprised. “We’ve been skeptical on an accelerated approval path,” they said in a note to investors Thursday, insisting that the FDA’s refusal to consider accelerated approval is “not thesis changing” for Edgewise.
The company’s stock slipped 10% on Thursday after the news.
According to Edgewise, the FDA said that data from the Phase II CANYON study, which Edgewise was proposing as the sole basis for sevasemten’s accelerated approval, are “insufficient.” Still, the FDA affirmed that scores on the North Star Ambulatory Assessment (NSAA)—a rating scale used to evaluate motor abilities—can be considered as a “clinically meaningful endpoint for traditional approval.”
Following a meeting with the FDA, Edgewise in its statement assured investors that it sees a “clear path to registration” for sevasemten. The biotech has already launched a global pivotal trial for sevasemten in Becker muscular dystrophy (BMD). The study, dubbed GRAND CANYON, is “highly powered” to demonstrate significance in NSAA improvements versus placebo, the company said.
The FDA has “emphasized their support for GRAND CANYON . . . and its potential as a single adequate well-controlled study to support registration” for sevasemten, Edgewise said on Thursday.
Truist Securities analysts shared some of Edgewise’s optimism. Although they had expected that the FDA wouldn’t sign off on an accelerated pathway for sevasemten, “we continue to see an opportunity in BMD,” the group wrote in a Thursday note, adding that the approval of sevasemten will “likely” come after GRAND CANYON reads out in the fourth quarter of 2026.
On this front, Stifel isn’t keeping its hopes up. “GRAND CANYON data remain on-track for 4Q26, where our expectations remain tempered” given that data from CANYON were “hard to interpret,” the analysts wrote.
“We think there’s really interesting basic science/mechanistic rationale behind sevasemten, the [Phase III study] seems very well-powered, and the drug definitely does have a shot,” they added. “It’s just hard for us to build a lot of conviction.”
Also on Thursday, Edgewise provided an update for its Duchenne muscular dystrophy program for sevasemten, pointing to a favorable tolerability profile in the Phae III LYNX and FOX trials. The biotech called topline data from these studies “encouraging,” including promising signals of efficacy in terms of functional outcomes.
However, as in the case of BMD, analysts did not seem convinced. “We find it hard to get a ton of conviction here,” Stifel wrote, adding that their analysts “still see considerable clinical risk ahead of a potential [Phase III study]—we expect investors will remain generally skeptical here as well.”
