The US Food and Drug Administration (FDA) has agreed to review a biologics licence application (BLA) by Novartis seeking approval for Zolgensma (AVXS-101) for treating spinal muscular atrophy (SMA) Type 1.
SMA Type 1 is a genetic neuromuscular disorder characterised by loss of motor neurons that regulate muscle functions such as breathing, swallowing, speaking and walking. The condition eventually leads to paralysis or death.
Zolgensma is an investigational gene replacement therapy. The product is designed to be administered as a single, one-time infusion to replace the missing or defective SMN1 gene with a functional copy.
The functional copy is intended to create SMN protein and consequently improve motor neuron function and survival.
Zolgensma was added to Novartis’s portfolio during its acquisition of AveXis in May. The drug candidate secured both breakthrough therapy and priority review designations from the FDA.
AveXis president David Lennon said: “Babies affected by this rare disease are currently faced with debilitating disease progression and lifelong invasive chronic treatment.
“As a one-time infusion that addresses the genetic root cause of SMA without the need for repeat dosing, Zolgensma represents a potentially significant therapeutic advance for these patients and their families.”
The BLA includes data from START clinical trial, when all 15 patients treated with Zolgensma were alive without the need for permanent ventilation at 24 months.
In addition, 92% of patients who received the proposed therapeutic dose were able to sit unassisted for nearly five seconds. This is said to be a first in the natural history of SMA Type 1.
Participants in an ongoing observational long-term follow-up of the trial are reported to have maintained their developmental motor milestones.
Novartis expects the FDA regulatory action in May 2019.