Breaking News - It is the first day of SMA month and cannot think of a better way to start the month than with the announcement by Biogen that their Phase 3 spinal muscular atrophy (SMA) trial testing nusinersen met its primary endpoint.
And the data is impressive enough to allow the sponsors of the trial – Biogen and Ionis—to stop the sham-controlled trial and allow all patients to enter an open label extension.
ENDEAR is a Phase 3 multicenter, double-blind, randomized, sham-procedure controlled study of nusinersen dosed in patients with infantile-onset SMA. Subjects will be randomized 2 to 1 to receive administered intrathecal injection of nusinersen or a sham procedure control, respectively. Patients were 7 months or younger at screening and diagnosed with SMA.
While details of the efficacy and safety are not fully known, Biogen announced that the analysis found that infants receiving nusinersen experienced a statistically significant improvement in the achievement of motor milestones compared to those who did not receive treatment.
Biogen is working to open a global expanded access program (EAP) for eligible patients with infantile-onset SMA (consistent with Type 1) in the near future. The EAP can be initiated at existing nusinersen clinical trial sites in countries where EAPs are permitted.
In a webcast, Biogen stated they hope to have the data submitted to the FDA by the end of the year.
Nusinersen is an antisense oligonucleotide (ASO) designed to alter the splicing of SMN2, a gene that is nearly identical to SMN1, in order to increase production of fully functional SMN protein. ASOs are short synthetic strings of nucleotides designed to selectively bind to target RNA and regulate gene expression.
Spinal Muscular Atrophy
SMA is a disease that robs people of physical strength by affecting the motor nerve cells in the spinal cord, taking away the ability to walk, eat, or breathe. It is the number one genetic cause of death for infants. SMA is caused by a mutation in the survival motor neuron gene 1 (SMN1). SMA affects approximately 1 in 10,000 babies, and about 1 in every 50 Americans is a genetic carrier.