Shares of Solid Biosciences Inc (NASDAQ:SLDB) rose 3% in Monday's premarket trading after the company reported a positive regulatory step for its Duchenne muscular dystrophy candidate, SGT-003.
The company said it has secured alignment with the U.S. Food and Drug Administration on the design of its pivotal Phase 3 study, IMPACT DUCHENNE. According to Solid Biosciences, the FDA agreed that a randomized, double-blind, placebo-controlled protocol was a reasonable approach, including the parameters defining the patient population.
Solid Biosciences expects to begin dosing the first participant in the Phase 3 trial during the first quarter of 2026. The company also plans additional meetings with the FDA in the first half of 2026 to discuss whether SGT-003 could pursue an accelerated approval pathway.
"As outlined at the start of 2026, we have structured our U.S. regulatory strategy around engaging with the FDA regarding a potential accelerated approval pathway for SGT-003, and the successful alignment on the design of our Phase 3 IMPACT DUCHENNE trial marks a critical first step in that plan," said Bo Cumbo, President & CEO of Solid Biosciences.
In addition to the regulatory update, Solid provided an update on its ongoing Phase 1/2 study, INSPIRE DUCHENNE. The company reported that 36 participants had been dosed as of February 9, 2026, and that SGT-003 continues to be generally well tolerated in that study.
IMPACT DUCHENNE is planned to enroll patients across multiple geographies, with sites currently planned in Australia, Canada, the European Union and the United Kingdom. The company said it is evaluating whether to open additional sites in the United States, citing strong interest from key opinion leaders and from patients.
Summary of facts:
- FDA and Solid Biosciences aligned on randomized, double-blind, placebo-controlled Phase 3 design for IMPACT DUCHENNE.
- First Phase 3 dosing targeted for Q1 2026.
- Additional FDA meetings on a potential accelerated approval pathway planned for H1 2026.
- INSPIRE DUCHENNE Phase 1/2 has dosed 36 participants as of Feb 9, 2026, with SGT-003 generally well tolerated.
- Planned IMPACT trial sites include Australia, Canada, the EU and the UK; U.S. sites under consideration.
This update prompted modest positive movement in the company's stock during premarket hours, reflecting investor attention on regulatory milestones and clinical advancement for SGT-003.