Genentech announced positive topline results from the pivotal Part 2 of the FIREFISH study, which evaluated risdiplam in infants aged 1-7 months with Type 1 spinal muscular atrophy (SMA). The primary outcome measure of the study was the proportion of infants sitting without support for at least five seconds at 12-months of treatment, assessed by the Gross Motor Scale of the Bayley Scales of Infant and Toddler Development – Third Edition (BSID-III). Data demonstrated statistically significant and medically meaningful motor milestone improvement in infants with Type 1 SMA.
FIREFISH is a two-part, open-label, pivotal study in infants aged 1-7 months with Type 1 SMA. Part 1 (n=21) assessed the safety profile of risdiplam and determined the dose for Part 2. Part 2 (n=41) assessed efficacy using the measurement stated above. Safety for risdiplam in the FIREFISH study was consistent with its known safety profile and no new safety signals were identified. To date, more than 400 patients have been treated with risdiplam across all studies, with no treatment-related safety findings leading to study withdrawal in any risdiplam trial.
Data from the FIREFISH study will be presented at an upcoming medical congress.
Three additional trials are currently underway in patients with SMA: SUNFISH met the primary endpoint as reported in November of 2019 and data will be presented at an upcoming medical congress; JEWELFISH is close to completing recruitment and RAINBOWFISH, which is currently recruiting approximately 25 infants from birth to 6 weeks of age (at first dose) with genetically diagnosed SMA who are not yet presenting with symptoms.
Risdiplam is a survival motor neuron-2 (SMN-2) splicing modifier for SMA and is an orally administered liquid. It is designed to increase and sustain SMN protein levels both throughout the central nervous system and peripheral tissues of the body. It is being evaluated for its potential ability to help the SMN-2 gene produce more functional SMN protein throughout the body.
About Spinal muscular atrophy (SMA)
Spinal muscular atrophy (SMA) is a severe, inherited, progressive neuromuscular disease that causes devastating muscle atrophy and disease-related complications. It is the most common genetic cause of infant mortality and one of the most common rare diseases, affecting approximately one in 11,000 babies. SMA leads to the progressive loss of nerve cells in the spinal cord that control muscle movement. Depending on the type of SMA, an individual’s physical strength and their ability to walk, eat or breathe can be significantly diminished or lost.
SMA is caused by a mutation in the survival motor neuron-1 (SMN-1) gene that results in a deficiency of SMN protein. SMN protein is found throughout the body and increasing evidence suggests SMA is a multi-system disorder and the loss of SMN protein may affect many tissues and cells, which can stop the body from functioning.