New data from a pivotal trial of Biogen’s Spinraza for infants with spinal muscular atrophy (SMA) shows it can improve survival and reduce the chances that they go on to need mechanical ventilation.
The new results come from the ENDEAR trial, which was halted earlier after showing a clear benefit for Spinraza (nusinersen) over placebo in SMA, an often fatal genetic disease affecting muscle strength and movement that develops in infancy.
In a nutshell, the data shows that 68% of infants who did not receive Spinraza died or needed permanent mechanical ventilation by the end of the study, compared to 39% of those who received the active drug. That equates to a statistically-significant risk reduction of 47%.
The data was presented at the British Paediatric Neurology Association (BPNA) annual conference in Cambridge, UK, which was the first presentation of the pre-specified primary endpoint from the end of study (EOS) analysis.
Biogen will need compelling data for Spinraza as it tries to persuade healthcare payers to stump up for the drug’s $750,000 annual price tag in the first year of treatment (ahead of any discounts or rebates), dropping to $375,000 per year thereafter.
Leerink analyst Geoffrey Porges suggested recently the price for Spinraza could bring rare disease therapies to the forefront of the pharma pricing debate and could lead to rationing, with Spinraza reserved for use only in the sickest patients.
“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,” said Biogen’s senior medical director for clinical development Wildon Farwell.
The drug is now being rolled out to its first patients in the US, said Farwell, who added that Biogen “continues to work closely with regulatory agencies to bring this therapy to patients around the world as quickly as possible”.
Spinraza is an antisense oligonucleotide drug licensed by Biogen from Ionis Pharma last year for $75m upfront and $150m in regulatory milestones, as well as royalties on sales. Analysts at Credit Suisse have previously suggested that sales could top $1bn by 2020.