Biogen Completes Submission of New Drug Application for SMA Therapy Nusinersen

Biogen has completed its rolling submission of a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for the approval of nusinersen for the treatment for spinal muscular atrophy (SMA).

Biogen has also applied for a Priority Review designation which, if granted, means the FDA should take action on an application within six months after the agency’s acceptance of the NDA.

Nusinersen is a drug designed to increased production of the SMN protein by altering the splicing of SMN2, a gene closely related to SMN1, thereby compensating for the loss or defect of this gene. The drug, being developed through a partnership between Ionis Pharmaceuticals and Biogen, has been granted orphan drug status by the FDA and the European Commission and fast track designation by the FDA.

A Marketing Authorization Application (MAA) for nusinersen is planned for submission to the European Medicines Agency (EMA) later this year. The EMA’s Committee for Medicinal Products for Human Use (CHMP) has granted Accelerated Assessment to nusinersen, which can lessen the usual time the agency takes to review the application. Biogen will begin regulatory filings in other countries in the coming months.

The regulatory submissions were based on the clinical findings from the interim analysis of ENDEAR, a Phase 3 clinical trial that evaluated nusinersen in infantile-onset (consistent with Type 1) SMA. Results from the interim analysis indicated nusinersen-treated infants showed a statistically significant improvement in achieving motor milestones compared to infants treated with a placebo. The safety profile of nusinersen was acceptable.

“Since announcing the positive results of the ENDEAR interim analysis in infantile-onset SMA last month, we have heard from many families expressing their excitement about nusinersen. Their stories continue to inspire us and they are in the forefront of our minds as we work to support the FDA’s review of nusinersen,” Dr. Alfred Sandrock, MD, PhD, executive vice president and chief medical officer of Biogen, said in a press release.

“We appreciate the FDA’s collaboration with us during the application process, and we look forward to continuing this productive dialogue, with the goal of rapidly bringing the first treatment for SMA to as many patients as possible,” he said.

Biogen expects to have a response from regulatory agencies about the acceptance and validation of these submissions within the next few months.

“Our ability to advance the nusinersen program as quickly as we have is largely due to the tremendous contributions of the entire SMA community, from the patients and families who participated in the clinical trials to the doctors, nurses, and advocates who work tirelessly on their behalf,” said Ionis CEO B. Lynne Parshall. “We are deeply appreciative of their unwavering commitment to finding a treatment for SMA, and today’s milestone is truly a collective achievement.”

SMA, a genetic disease that affects the control of muscle movement, is caused by the absence or defect of the survival motor neuron 1 (SMN1) gene, which in turn decreases the production of the survival motor neuron (SMN) protein, which is essential for the healthy maintenance and survival of motor neurons.

The clinical program of nusinersen comprised two Phase 3 clinical trials assessing the effectiveness and safety of the drug in infants and children with SMA: ENDEAR and CHERISH, respectively. The investigational drug is also being evaluated by Biogen and Ionis in four Phase 2 clinical trials.