- Biogen's Spinraza (nusinersen), approved by the Food and Drug Administration in late-December, cuts the risk of death or need for permanent ventilation in infants with spinal muscular atrophy (SMA), according to results presented in the U.K. this week.
- The Phase 3 study was stopped early so that all participants could receive the active drug. In the end-of-study analysis, Spinraza met a primary endpoint, with a statistically significant 47% reduction in the risk of death or permanent ventilation.
- Adverse effects included respiratory events and constipation, but these were similar to those seen in infants with untreated SMA. The results were presented at the British Paediatric Neurology Association's (BPNA) annual conference in Cambridge, U.K.
Spinraza attracted attention earlier this month, both for an earlier-than-expected U.S. approval five months and for its lofty price tag — $750,000 for the first year and then $375,000 a year for life.
High-priced drugs have spurred backlash recently as drug pricing became part of the political rhetoric in an election year. While highly innovative drugs and rare disease drugs have received less attention than some, the Biogen drug was priced at the high end of expectations.
SMA is a rare and inherited wasting disease, and Spinraza is the first drug approved for its treatment.
Biogen is likely hoping that this new data will help it justify the cost of its antisense drug, which was licensed from Ionis Pharmaceuticals. So far, however, it has not had any noticeable impact on the company's share price.
"Although ENDEAR was stopped early based on positive interim results, the study still demonstrated that a significantly greater number of infants treated with Spinraza survived and did not require permanent ventilation. These data further underscore the impact Spinraza may have on individuals living with this devastating disease," said Wildon Farwell, senior medical director of clinical development at Biogen.
Spinraza has won accelerated assessment status in Europe, and is pending approval in that market. It has also been submitted in Japan, Canada and Australia, with other filings planned in 2017.
"Individuals with SMA have already started treatment with Spinraza this week in the U.S., and we continue to work closely with regulatory agencies to bring this therapy to patients around the world as quickly as possible," Farwell added.
AveXis, Biogen's nearest rival in SMA, has a pivotal trial for its gene therapy AVXS-101 slated for the first half of 2017, though its first step to the market is still likely to be some ways away.