Solid Bioscience's Duchenne muscular dystrophy (DMD) gene therapy candidate, SGT-003, has received Rare Pediatric Disease Designation from the FDA, the company announced in a press release.¹

“Preclinical data suggests that SGT-003 has potential to significantly improve on existing treatments for Duchenne by using a muscle tropic proprietary capsid to deliver a DNA sequence encoding a shortened form of the dystrophin protein which, importantly, includes the nNOS binding domain," said Gabriel Brooks, MD, chief medical officer, Solid Biosciences.¹

The planned phase 1/2 INSPIRE Duchenne trial (NCT06138639) is a first in-human, open-label, multicenter trial to evaluate tolerability and safety of SGT-003 at a dose of 1E14vg/kg in pediatric DMD patients.^1,2

The trial will feature 2 cohorts. Cohort 1 will include male patients aged 4 to younger than 6 years, while cohort 2 will feature male patients aged 6 to younger than 8 years.²

The candidate will be administered as a 1-time intravenous infusion to the patients in both cohorts (minimum of 3 patients each), with the potential for cohort expansion.¹

Inclusion criteria for the planned trial is²:

• Ambulatory defined as "being able to walk without the use of an assistive device."
• AAV antibody negative
• Patients on a stable dose of at least 0.5 mg / kg / day of oral daily prednisone or 0.75 mg / kg / day deflazacort for 12 weeks or longer prior to study entry
• Cohort 1 < 18 kg body weight
• Cohort 2 < 30 kg body weight

Exclusion criteria includes, but is not limited to²:

• Current or previous treatment with approved or investigational dystrophin modifying drugs such as eteplirsen, golodirsen, casimersen, and viltolarsen
• Current or prior treatment with an approved or investigational gene transfer drug
• Exposure to another investigational drug within 3 months prior to screening or 5 half-lives since last administration, whichever is longer
• Established clinical diagnosis of DMD that is associated with any deletion mutation in exons 1 to 11 or 42 to 45, inclusive, in the DMD gene as documented by a genetic report and confirmed by Sponsor genetic testing

"We look forward to rapidly bringing SGT-003 to the clinic and hope to all Duchenne patients in need," added Brooks.¹

DMD, the genetic muscle-wasting disease that generally affects males, has symptoms that usually appear between ages 3 and 5 years. The progressive and irreversible disease impacts approximately 1 in every 3500 to 5000 live male births in the United States, which has an estimated prevalence of 5000 to 15,000 cases.¹

According to Solid Biosciences, "SGT-003 uses a proprietary, rationally designed capsid (AAV-SLB101) to deliver a DNA sequence encoding a shortened form of the dystrophin protein (microdystrophin), containing the R16-R17 nNOS binding domain."¹

Locations that are currently recruiting, according to clinicaltrials.gov, are University of California, Los Angeles Medical Center and Nationwide Children's Hospital, Columbus, Ohio.²

Click here for contact information regarding recruiting clinical trial locations.²

More DMD coverage: FDA approves givinostat for Duchenne muscular dystrophy in patients 6 years and up

The decision makes givinostat the first nonsteroidal drug approved to treat patients with all genetic variants of DMD.

Read the full FDA approval article, here.

References:

1. Solid Biosciences receives Rare Pediatric Disease Designation from the FDA for Duchenne muscular dystrophy gene therapy candidate SGT-003. Solid Biosciences. Press release. April 1, 2024. Accessed April 2, 2024. https://investors.solidbio.com/news-releases/news-release-details/solid-biosciences-receives-rare-pediatric-disease-designation

2. A study of SGT-003 gene therapy in Duchenne muscular dystrophy (INSPIRE DUCHENNE). ClinicalTrials.gov. Updated March 29, 2024. Accessed April 2, 2024. https://classic.clinicaltrials.gov/ct2/show/NCT06138639