Roche has reported positive data from the dose finding Part I FIREFISH study of Evrysdi (risdiplam) in infants with symptomatic Type 1 spinal muscular atrophy (SMA).

Evrysdi is a survival of motor neuron 2 (SMN2) splicing modifier designed for treating SMA by boosting SMN protein production. The protein is seen all over the body and is vital to maintaining healthy motor neurons and movement.

A severe, progressive neuromuscular disease, SMA is a major genetic cause of infant mortality.

FIREFISH, an open-label, two-part pivotal study was designed to assess the safety, tolerability, efficacy, pharmacokinetics (PK) and pharmacodynamics (PD) of Evrysdi in patients aged one to seven months with Type 1 SMA.

Part 1 was a dose-escalation study that enrolled 21 infants with the primary goal of evaluating the safety profile of Evrysdi in the subjects and dose determination for Part 2.

The Part 2 single-arm study enrolled 41 infants who received treatment for two years, followed by an open-label extension.

Evaluating efficacy as measured by the proportion of infants sitting without support after 12 months of treatment was the primary objective of Part 2.

According to the latest data, Evrysdi treatment at 12 months helped 90% of infants survive without needing permanent ventilation and 33% sit without support for at least five seconds.

Furthermore, it raised the survival levels of motor neuron (SMN) protein by a median 1.9-fold from baseline in the high-dose group at 12 months.

Roche Global Product Development chief medical officer and head Levi Garraway said: “Since Evrysdi was FDA approved in August, we have been inspired by the stories and sense of hope that we have heard from people living with SMA and their families about the impact Evrysdi has had in their lives.

“The publication of the data in the New England Journal of Medicine reinforces the value of Evrysdi as an important treatment option for SMA.”

Last September, Roche reported that Evrysdi lowered the mortality rate in infants aged two to seven months with symptomatic type 1 SMA in the FIREFISH trial.