The main beneficiary of Roche’s discontinuation of an investigational spinal muscular atrophy drug is Scholar Rock, which was hobbled by manufacturing concerns at a Novo Nordisk facility last year but is now nearing a potential resolution.
Roche is no longer advancing its mid-stage anti-myostatin therapy for spinal muscular atrophy, a move that the company chalked up to underwhelming data. Other developers in the space now have an opening to establish a presence in the market.
The decision to discontinue the spinal muscular atrophy (SMA) asset, dubbed emugrobart, was “difficult,” Roche’s subsidiary Genentech said in a letter to patients on Thursday. The pharma had been studying emugrobart in the Phase 2/3 MANATEE study, which combined the anti-myostatin antibody with the company’s own SMA drug Evrysdi. A total of 259 patients were enrolled.
Data from the trial’s first part showed that emugrobart “did not consistently deliver the improvements we hoped for in muscle growth and motor function,” Roche wrote. MANATEE compared emugrobart to Evrysdi alone. The pharma emphasized that MANATEE was not axed due to safety concerns, and that emugrobart remains well-tolerated with no side effects pushing patients to drop out.
Roche did not provide specific data in its Thursday letter, promising to share a more detailed analysis of MANATEE at an upcoming scientific congress.
“We recognize this news will be disappointing to the SMA community,” the pharma noted, expressing its gratitude to the study participants, caregivers and people involved with the trial. Patients enrolled in MANATEE will be transitioned away from emugrobart and to Evrysdi treatment.
Roche on Thursday also said that it will no longer develop emugrobart for facioscapulohumeral muscular dystrophy, similarly explaining that the drug “did not consistently deliver the hoped for improvements in muscle growth and function.” The pharma continues to develop emugrobart for obesity, for which it is running a mid-stage study with a regulatory filing expected by 2028 at the earliest, according to its pipeline page.
While the demise of MANATEE deals an immediate blow to the SMA patient community, analysts expect the news to positively affect other drugmakers in this space. The chief beneficiary, according to both BMO Capital Markets and Truist Securities, is Scholar Rock, which is advancing apitegromab, also a myostatin blocker.
Roche’s discontinuation “sets [the] stage for apitegromab domination,” Truist analysts told investors in a Thursday note, adding that without emugrobart, Scholar Rock will now have “no competition for future market share in the anti-myostatin/muscle-enhancing SMA space.”
In September 2025, apitegromab ran into a regulatory speedbump when the FDA rejected its application for SMA. The rebuff was not driven by issues with the drug’s efficacy or safety but was instead linked to problems at a third-party Catalent manufacturing site owned by Novo Nordisk.
“Things appear to be looking up for Scholar Rock following a challenged 2025 due to Novo/Catalent-associated regulatory delays,” BMO analysts told investors in a Thursday note.
“As CMC issues near resolution, investor focus is likely beginning to shift to the commercial opportunity and potential initial sales for apitegromab in SMA”—and on this front, Roche’s pullout could be a boon for Scholar Rock, the firm added.
Also on Thursday, Roche discontinued a mid-stage study for its RIPK1 inhibitor flizasertib for acute kidney injury in patients undergoing cardiac surgery. The decision to end the Phase 2 trial was driven by early data, which “indicated that the study was unlikely to demonstrate a significant clinical benefit,” a company spokesperson told Fierce Biotech.
