United States – October 28, 2026 -- Solid Biosciences has dosed 40 participants with its Duchenne gene therapy SGT-003 and reported positive interim safety and biomarker data from the ongoing Phase 1/2 INSPIRE DUCHENNE trial. The company presented the update at the 2026 MDA Clinical & Scientific Conference.
The therapy delivers a shortened dystrophin protein
SGT-003 delivers microdystrophin, a shortened version of dystrophin designed to help support and protect muscle cells during movement. The data show robust microdystrophin expression. They also show restoration of beta-sarcoglycan and nNOS, proteins that normally work with dystrophin in the dystrophin-associated protein complex (DAPC), the muscle cell support system.
Muscle health markers point in a favorable direction
Muscle tissue showed fewer eMHC fibers, which appear when muscle is repeatedly injured and repairing itself. Blood levels of CK, ALT, AST, LDH and titin were also reduced. These proteins can leak into the bloodstream when muscle cells are injured. The data also include heart function measures, including left ventricular ejection fraction (LVEF), which shows how well the heart pumps blood.
Safety profile is encouraging with a steroid-only regimen
As of March 11, 2026, SGT-003 had been generally well tolerated in all 40 dosed participants. It is given with a lower-burden, steroid-only prophylactic immunomodulation regimen.
FDA talks on accelerated approval are under way
Solid Biosciences is meeting with the FDA to get guidance on a potential accelerated approval pathway for SGT-003. It expects to share further regulatory updates after those meetings. The company also plans written updates and community webinars for Duchenne families.