FDA Approves Genentech’s SMA Therapy, the First At-Home Treatment

Rare Daily Staff

The U.S. Food and Drug Administration approved Genentech’s Evrysdi for treatment of spinal muscular atrophy in adults and children 2 months of age and older.

SMA is a severe, progressive neuromuscular disease that can be fatal. It is caused by a mutation of the survival motor neuron 1 (SMN1) gene, which leads to a deficiency of SMN protein. This protein is found throughout the body and is essential to the function of nerves that control muscles and movement. Without it, nerve cells cannot function correctly, leading to muscle weakness over time. Depending on the type of SMA, an individual’s physical strength and their ability to walk, eat or breathe can be significantly diminished or lost.

Evrysdi is a survival of motor neuron 2 (SMN2) splicing modifier designed to treat SMA caused by mutations in chromosome 5q that lead to SMN protein deficiency. Evrysdi, a liquid medicine, is administered daily at home by mouth or feeding tube. It is the first and only at-home therapy approved to treat SMA.

The medicine showed clinically meaningful improvements in motor function across two clinical trials in people with varying ages and levels of disease severity, including Types 1, 2, and 3 SMA. Infants achieved the ability to sit without support for at least 5 seconds, a key motor milestone not normally seen in the natural course of the disease. Evrysdi also improved survival without permanent ventilation at 12 and 23 months, compared to natural history.

“Given the majority of people with SMA in the U.S. remain untreated, we believe Evrysdi, with its favorable clinical profile and oral administration, may offer meaningful benefits for many living with this rare neurological disease,” said Levi Garraway, chief medical officer and head of Global Product Development, Genentech. “The strength and resolve of the SMA community has continually inspired us as we developed this first-of-its-kind medicine for SMA, so today we celebrate our collective accomplishment together with them.”

Evrysdi demonstrated a favorable efficacy and safety profile, with the safety profile established across the FIREFISH and SUNFISH trials. The most common adverse reactions were fever, diarrhea, and rash in later-onset SMA. In infantile-onset SMA, the most common adverse events were similar and included upper respiratory tract infection, pneumonia, constipation, and vomiting. There were no treatment-related safety findings leading to withdrawal from either study. 

Evrysdi will be available in the United States within two weeks for direct delivery to patients’ homes through Accredo Health Group Inc., an Express Scripts specialty pharmacy. 

Photo: Levi Garraway, chief medical officer and head of Global Product Development