Roche clears FDA hurdle with investigational drug 'risdiplam'

Roche announced on Monday that the US Food and Drug Administration (FDA) has accepted the new drug application and granted ‘Priority Review’ status for ‘risdiplam’, an investigational survival motor neuron-2 (SMN-2) splicing modifier for spinal muscular atrophy (SMA).

The Swiss pharmaceuticals giant said risdiplam was designed to increase and sustain SMN protein levels both throughout the central nervous system and peripheral tissues of the body.

The FDA was expected to make a decision on approval by 24 May 2020.

Roche said the risdiplam NDA submission incorporated 12 months of data from the dose-finding part 1 sections of the ‘FIREFISH’ and ‘SUNFISH’ pivotal studies, as well as data from the confirmatory part 2 of SUNFISH.

It described FIREFISH as an open-label, two-part pivotal clinical trial in infants with type 1 SMA, with part 1 being a dose-escalation study in 21 infants aged between one and seven months.

The primary objective of part 1, which evaluated efficacy as an exploratory endpoint, was to assess the safety profile of risdiplam in infants and determine the dose for part 2, which was designed as a pivotal, single-arm trial evaluating risdiplam in 41 infants with type 1 SMA for 24 months, followed by an open-label extension.

SUNFISH, meanwhile, was described as a two-part, double-blind, placebo-controlled pivotal clinical trial in children and young adults aged between two and 25 years, with type 2 or 3 SMA.

Part 1 determined the dose for the confirmatory part 2, and evaluated efficacy as an exploratory endpoint.

SUNFISH part 2 was described as a large placebo-controlled trial evaluating treatment for people with type 2 or 3 SMA.

That part recently met its primary endpoint of change from baseline in the motor function measure 32 (MFM-32) scale.

No treatment-related safety findings leading to study withdrawal had been seen in any risdiplam trial to date, Roche reported.

It said safety for risdiplam was consistent with its known safety profile, and no new safety signals were identified.

The results, it said, would be presented at an upcoming medical congress.

If approved, risdiplam - an orally administered liquid - would be the first at-home administered medicine for people living with SMA.

In addition to the studies included in the new drug application submission, risdiplam was being studied in a broad clinical trial programme in SMA, with patients ranging from newborns to 60 years old, including patients previously treated with SMA therapies.

Roche said it was leading the clinical development of risdiplam as part of a collaboration with the SMA Foundation and PTC Therapeutics, and would commercialise the medicine in the United States if approved.

“The FIREFISH and SUNFISH trials were designed to represent the real world spectrum of people living with SMA and include many people previously underrepresented in clinical trials,” said Roche’s chief medical officer and head of global product development, Levi Garraway.

“We look forward to working closely with the FDA to explore broad access to risdiplam for all individuals in the community who might benefit.”