Biogen’s NDA for nusinersen to treat spinal muscular atrophy (SMA) has been accepted by the FDA for Priority Review which should reduce the review time for the drug. The drug also has an ‘Accelerated Assessment” designation in Europe.
In a press release
, Michael Ehlers, MD, PhD, executive vice president, head of Research and Development at Biogen said, “The FDA and EMA have acknowledged the potential for nusinersen to address the urgent need for an effective SMA treatment by granting special status to the applications, and FDA has shared that they plan to act early on our NDA under an expedited review.”
The regulatory filing packages in the US and EU are based on data that demonstrate the clinically meaningful efficacy and favorable safety profile of nusinersen from multiple studies, including the phase 3 ENDEAR study involving infantile-onset SMA (Type I SMA) hat demonstrated that infants receiving nusinersen experienced a statistically significant improvement in the achievement of motor milestones compared to those who did not receive nusinersen.
What is Spinal Muscular Atrophy?
SMA is a genetic condition that leads to a deficiency in the spinal motor neuron (SMN) protein as a result of mutations of the survival motor neuron 1 (SMN1) gene. The severity of SMA correlates with the amount of SMN protein. Generally, the muscles most affected are those near the shoulders, hips, thighs and upper back. Muscles used for breathing and swallowing may also be affected. Infants with Type I SMA produce very little SMN protein and have a life expectancy of less than two years. Children with Type II have greater amounts of SMN protein but still have a shortened lifespan and are never able to stand independently. Children with Type III have a normal lifespan but accumulate life-long physical disabilities as they grow.
Nusinersen is an antisense oligonucleotide (ASO) that is designed to alter the splicing of pre-mRNA from the SMN2
gene in order to increase production of fully functional SMN protein. Nusinersen is being investigated in Type I, II, and III SMA populations.