Onasemnogene abeparvovec is a gene replacement therapy used to treat type 1 spinal muscular atrophy (SMA). This type of SMA is characterized by onset before 6 months of age. This study, published in JAMA Neurology, studied the use of onasemnogene abeparvovec over 6.2 years following therapeutic administration.
The study had two principal objectives: determine the safety of onasemnogene abeparvovec treatment and determine whether or not the milestones achieved during the clinical trial were maintained over a longer period. A total of 13 infants with SMA type 1 and type 2 were included in the study.
Ultimately, serious adverse events, including acute respiratory failure, bronchiolitis, dehydration, pneumonia, and respiratory distress occurred in 8 patients. None of these adverse events resulted in study discontinuation or death. Moreover, all patients who received the therapeutic dose of onasemnogene abeparvovec maintained their previously acquired milestones and experienced sustained efficacy.
The researchers concluded that these data on onasemnogene abeparvovec provide a favorable long-term safety profile for children with SMA up to 6 years of age. The study also supports the prolonged durability of the therapeutic dose given during the trial period [1].
Source:
[1] Mendell, J. R., Al-Zaidy, S. A., Lehman, K. J., McColly, M., Lowes, L. P., Alfano, L. N., Reash, N. F., Iammarino, M. A., Church, K. R., Kleyn, A., Meriggioli, M. N., & Shell, R. (2021). Five-year extension results of the phase 1 START trial of onasemnogene abeparvovec in spinal muscular atrophy. JAMA Neurology, 78(7), 834. https://doi.org/10.1001/jamaneurol.2021.1272
