The usual end-year flurry of FDA approvals didn’t happen in 2016, although Biogen got the okay for its spinal muscular atrophy (SMA) drug Spinraza as the year drew to a close.
Spinraza (nusinersen) became the first drug to be approved in the US to treat children and adults with SMA – an often fatal genetic disease affecting muscle strength and movement – just ahead of the Christmas break.
SMA affects 1 in 6,000 to 10,000 live births and is a leading cause of genetic death in infants and in severe cases patients become paralysed and lose the ability to carry out basic functions such as swallowing and breathing.
Spinraza is an antisense oligonucleotide drug licensed by Biogen from Ionis Pharma last summer 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.
Their high expectations for the drug are based on lofty pricing predictions, and Biogen has stuck to the rare disease therapy script by pricing Spinraza at an eye-watering $750,000 for the first year, dropping to $375,000 per year thereafter.
Leerink analyst Geoffrey Porges said the price of the drug could be “the straw that breaks the camel’s back” and bring rare disease therapies to the forefront of the pharma pricing debate. “The price is going to force payers to closely scrutinise which patients receive access and limit the overall access provided,” he said, suggesting patients with less severe forms of SMA could miss out.
The approval is based on a clinical trial in 121 patients with infantile-onset SMA who were diagnosed before six months of age and who were less than 7 months old at the time of first dosing. The infants received an injection of Spinraza, into the fluid surrounding the spinal cord, or a mock procedure (a skin prick) as a control.
The FDA asked the investigator team to look at the efficacy results as early as possible and approved the drug on the back of data from 82 subjects which showed 40% of Spinraza-treated patients showed motor improvements on measures such as head control, sitting, ability to kick in supine position, rolling, crawling, standing and walking. None of the control group showed any improvement.
Spinraza’s approval brought the tally of FDA approvals in 2016 to just 22 – well below the 40-plus counts of 2014 and 2015. In part that is because some drugs scheduled for approval in 2016 were approved early, ending up in the 2015 bracket, and there was also an increase in the number of applications that were turned down by the agency via a complete response letter (CRL).