SMA1 Clinical Program
About SMA1
Spinal muscular atrophy (SMA) is a progressive neurodegenerative disease that affects motor neurons in the spinal cord and adversely affects the skeletal muscles. Progressive muscle weakness impairs breathing, eating, crawling/walking, and other activities. SMA is caused by a mutation in the survival motor neuron gene 1 (SMN1), and it follows an autosomal recessive pattern of inheritance. The global incidence of all types of SMA, whose severity is modulated by the number of SMN2 gene copies, is approximately 1:10,000 live births.
SMA Type 1 (SMA1) is a very severe form with early onset and diagnosis occurring at less than 6 months of age. Untreated SMA1 patients do not survive beyond 18 months of age. SMA1 patients typically have 1-2 copies of the SMN2 gene. SMA1 accounts for approximately 60% of global SMA cases (~1:17,000 live births).
Photo credit: Levi Gershkowitz
About GB221
GB221 is an investigational gene therapy created by GEMMABio. It consists of an adeno-associated virus (AAV) encasing a functional copy of a codon-optimized SMN1 gene in a modified transgene expression cassette designed to reduce overexpression-related toxicities and sensory neurotoxicity. It is a one-time treatment that is delivered directly to the cerebrospinal fluid (CSF) via intra-cisterna magna (ICM) injection.
In preclinical studies, GB221 improved survival and neuromotor function in a mouse model of SMA1. Furthermore, the investigational new therapy demonstrated high levels of motor neuron transduction without toxicity in non-human primates (NHPs).
Watch the video below for a summary.
Clinical Trial Participation
The clinical trial for GB221 is now open in Brazil. For more information about the study and eligibility criteria, please visit clinicaltrials.gov (NCT07070999).
The study name is A Phase 1-2, Open-Label, Multicenter Study to Assess the Safety, Tolerability and Efficacy of a Single Dose of GB221 Delivered Into the Cisterna Magna of Pediatric Participants From 2 Weeks to Younger Than 12 Months of Age With Spinal Muscular Atrophy Type 1, also known as ‘CHARISMA.’
