FDA delays decision on Roche's SMA drug to review extra data

The FDA has extended its review of Roche’s spinal muscular atrophy (SMA) drug risdiplam after the pharma submitted additional data.

Roche submitted data for risdiplam to the FDA in November, setting up a potential approval next month and a rivalry with Biogen and Novartis and their already-approved therapies for the rare muscle-wasting disease.

A decision from the FDA on risdiplam is now due before August 24, after Roche submitted additional data from the pivotal SUNFISH Part 2 study.

Roche said the additional data from SUNFISH could make the drug available to a broad range of people living with the condition.

SUNFISH Part 2 provided data in people aged 2-25 years with type 2 or 3 SMA, data which Biogen and Novartis have yet to produce.

Roche said that the FDA requires more time for the review because of the volume of additional data submitted.

The Swiss pharma has also filed for approval with regulators in Brazil, Chile, Indonesia, Russia, South Korea and Taiwan.

A filing in China is imminent and the company is on track to file with the European Medicines Agency in mid-2020 as well as other markets.

Roche has been leading clinical development of risdiplam, an orally administered motor neuron-2 (SMN2) splicing modifier for SMA as part of a collaboration with the SMA Foundation and PTC Therapeutics.

The drug is being studied in patients from birth to 60 years old, including patients previously treated with other SMA-targeting therapies.

This opens up the drug as a potential therapy should Novartis’ gene therapy Zolgensma, or Biogen’s Spinraza fail or produce a partial response.

Zolgensma (onasemnogene abeparvovec) is a one-off gene therapy that is approved for SMA patients aged under two, but is the world’s most expensive drug at up to $2.1 million for a single shot.

Spinraza was the first drug approved to treat the underlying cause of SMA in 2016, but is also hugely pricey at around $750,000 for the first year, and $375,000 annually from then onwards.

SMA is caused by an inherited deficiency in the motor neuron protein SMN, which is necessary for normal motor neuron function and survival.

Symptoms range from mild to severe, and babies with the most serious form of the condition often die at a very early age as they are unable to move or even breathe properly as the disease progresses.