Roche scores FDA priority review for risdiplam, threatening Biogen and Novartis SMA meds

Biogen and Novartis are battling in the lucrative spinal muscular atrophy (SMA) field, but a third entrant could shake up the market in 2020. Roche and PTC Therapeutics’ risdiplam just picked up an FDA priority review, setting up a potential nod by May. 

The FDA is reviewing the drug based on 12-month data from a study called Firefish in type 1 SMA patients, plus data in type 2 and 3 patients from a study called Sunfish. The drugmaker is testing the candidate in a broad patient population, ranging from newborns to age 60, including those who have taken other SMA meds. 

Risdiplam is an orally administered liquid that patients would take at home. Biogen's Spinraza is an injection with several loading doses over the first two-and-a-half months and maintenance doses every four months thereafter. Novartis’ gene therapy Zolgensma is a one-time treatment for patients under two. 

Analysts believe the new Roche drug could bring in $2.5 billion to $3 billion at peak. So far in 2019, Biogen’s Spinraza has pulled in $1.55 billion. Zolgensma has generated $160 million so far since launch. 

RELATED: Novartis' SMA gene therapy Zolgensma could struggle to hit blockbuster territory: report 

Risdiplam scored the FDA’s orphan drug designation in January 2017 and fast-track designation in April 2017. While the FDA’s official decision date is May 24, Cantor Fitzgerald analyst Alethia Young wrote that approval could come earlier than that. 

“We are seeing many therapies which address high unmet needs that are approved earlier” than FDA decision dates, she wrote in a note to clients. 

Regardless of when the drug scores a nod, analysts expect risdiplam to bring big changes to the market upon launch. Young wrote that it’ll “meaningfully change the SMA landscape in 2020."

Biogen launched its Spinraza first in the field and the rollout has surpassed all expectations. Novartis has hit some hiccups with Zolgensma, including a data manipulation controversy that didn't dent demand. Analysts still believe the med will generate blockbuster sales.