Phase 1b Trial for Solid Biosciences’ Friedreich Ataxia Gene Therapy SGT-212 Doses First Patient

The first patient has been dosed in the first-in-human phase 1b FALCON clinical trial (NCT07180355), which is evaluating Solid Biosciences’ SGT-212, an investigational adeno-associated virus (AAV) vector-based gene therapy product, for the treatment of FA.^1,2 The open-label, dose-finding study will include patients with FA aged 18 to 40 years.

SGT-212 is intended to address neurologic, cardiac, and systemic manifestations of the disease through a dual-route administration. The cerebellar dentate nuclei will first be targeted with a stereotactic, MRI-guided intradentate nuclei (IDN) infusion of SGT-212, and patients will also receive a subsequent intravenous infusion of the gene therapy. SGT-212 is intended to provide a functional copy of the full-length human frataxin gene in order to restore expression of the disease-targeted frataxin protein at therapeutic levels. Pending patient enrollment, Solid expects to announce initial data from the trial in the second half of 2026.

“We want to recognize the extraordinary leadership and partnership of the Friedreich’s Ataxia Research Alliance (FARA), whose ongoing guidance and support continue to shape and strengthen our clinical program,” Solid wrote in an open letter to the FA Community.¹ “We also wish to acknowledge the many scientists, clinicians, and partners whose collaboration made the development of SGT-212 and this dual-route gene therapy approach possible. This work reflects our shared determination to advance clinically meaningful therapies that address the urgent unmet needs of this community – to improve both survival and quality of life for people living with FA.”

On the same day as the announcement of the dosing of the first patient, Solid also reported that SGT-212 had received orphan drug designation from the FDA for the treatment of FA.² The company noted that the gene therapy has previously been granted fast track and rare pediatric disease designations by the FDA.

“Receiving orphan drug, fast track, and rare pediatric disease designations underscores the significant unmet need the FA community faces and recognizes the therapeutic potential of SGT-212’s novel, dual-route administration,” Jessie Hanrahan, PhD, the chief regulatory & preclinical operations officer at Solid Biosciences, said in a statement.² “We anticipate that the ability to leverage these regulatory designations will help streamline and potentially accelerate SGT-212’s development path, and we look forward to working closely with regulators to bring a potential new treatment option to the FA community.”

In addition to SGT-212, Solid is also developing several other gene therapy products. Of note is SGT-003, an investigational next-generation AAV vector-based gene therapy intended to treat Duchenne muscular dystrophy (DMD), which is currently being evaluated in the phase 1/2 INSPIRE DUCHENNE clinical trial (NCT06138639).³ According to a November 2025 update from Solid, 23 patients in the study had been dosed with the gene therapy product as of October 31, 2025. The company also reported interim results at the time, highlighting that 10 treated patients aged 5 to 10 years responded to SGT-003 with a mean of 58% microdystrophin expression by western blot in the Day 90 biopsy data.

“The interim INSPIRE DUCHENNE data reported today strengthens our confidence in SGT-003’s therapeutic potential,” Bo Cumbo, BS, the president and chief executive officer of Solid Biosciences, said in the November 2025 statement.³ “From strong observed biological correlations of SGT-003 microdystrophin expression levels with properly localized restoration of key components of the dystrophin-associated protein complex to early evidence of cardiac function normalization, we are observing a clear and cascading effect in the human body, suggesting a coordinated, systemic response to treatment. We believe these interim data represent one of the most thorough early analyses of any Duchenne gene therapy to date. The quality and concurrence of these interim findings reinforce our conviction in SGT-003’s potential to translate molecular impact into meaningful clinical outcomes.”

REFERENCES
1. Letter to the FA Community. Open letter. Solid Biosciences Inc. January 12, 2026. Accessed January 16, 2026. https://www.solidbio.com/letter-to-the-fa-community-jan2026/
2. Solid Biosciences receives FDA orphan drug designation for SGT-212 dual-route gene therapy for the treatment of Friedreich’s ataxia. News release. Solid Biosciences Inc. January 12, 2026. Accessed January 16, 2026. https://investors.solidbio.com/news-releases/news-release-details/solid-biosciences-receives-fda-orphan-drug-designation-sgt-212
3. Solid Biosciences reports third quarter 2025 financial results and provides update on INSPIRE DUCHENNE clinical trial progress and planned regulatory discussions. News release. Solid Biosciences Inc. November 3, 2026. Accessed January 16, 2026. https://investors.solidbio.com/news-releases/news-release-details/solid-biosciences-reports-third-quarter-2025-financial-results