Roche gains EU PRIME status for Spinraza rival

Roche has been granted PRIME (PRIority MEdicines) designation in the EU for risdiplam, its small-molecule drug for spinal muscular atrophy that could be a rival to Biogen’s Spinraza.

Risdiplam is currently in three studies that include patients with all types of SMA, a progressive and sometimes fatal neuromuscular disease which is caused by a defective or missing SMN1 gene. The drug is designed to increase levels of the SMN protein in the body and by helping another gene called SMN2 compensate for the loss in SMN1 activity.

If risdiplam proves its worth in the clinic and gets approved, the drug could offer an alternative to Spinraza, an antisense oligonucleotide that has to be delivered by injection into the fluid surrounding the spinal cord.

PRIME status takes it one step closer to fruition, as it will give Roche additional support from the EMA as the company prepares and files risdiplam for approval in Europe. Only one in five drugs submitted for PRIME end up being awarded the status.

Roche has preliminary data from its FIREFISH study in Type 1 SMA – the form that starts earliest in life and is most severe – showing risdiplam helped the infants meet developmental milestones, including sitting without support. In the SUNFISH trial in later-onset forms (Types 2 and 3), it has data suggesting the drug can improve motor function scores.

Results from FIREFISH and SUNFISH are due in 2019, with a third trial called JEWELFISH in people with all types of SMA aged 6 months–60 years who have been previously treated with SMN-targeting therapy will read out the following year. Prior treatment could include olesoxime, an experimental drug Roche acquired as part of its takeover of Trophos three years ago that was abandoned earlier this year after a failed phase 2 trial.

Meanwhile, a new trial called RAINBOWFISH, in newborns with pre-symptomatic SMA, will be started in early 2019, says Roche.

Roche reckons that risdiplam could have an advantage over drugs like Spinraza that are delivered only to the spinal cord because “the loss of SMN protein may affect many tissues and cells beyond the central nervous system.”

There is competition looming for both Spinraza and risdiplam in the form of Novartis’ one-shot gene therapy Zolgensma for Type 1 SMA, which attempts to correct the underlying genetic defect in the disease and has shown impressive efficacy in early clinical testing.

Spinraza has quickly become a big earner for Biogen since it was launched in 2017, with third quarter sales reaching $488m, driven by its high list price of $750,000 in the first year and $350,000 thereafter. That premium pricing strategy led NICE to reject the drug in draft guidance earlier this year.

So far, Roche hasn’t made any comment on its pricing strategy for risdiplam, but Novartis caused a stir when it suggested it would be reasonable to charge $4m for its gene therapy.