San Francisco-based genetics company Invitae is working with Biogen to help identify patients with the rare neuromuscular disease, spinal muscular atrophy (SMA). The collaborators will be offering Invitae’s genetic testing services at no charge to US patients who have been clinically diagnosed with SMA through the company’s new SMA Identified program.
“We know that genetic testing has the ability to accelerate the diagnostic process, and an early diagnosis could lead to earlier intervention and better medical outcomes for patients with SMA,” said Dr. Robert Nussbaum, chief medical officer of Invitae. “We’re pleased to be working together with Biogen on this program, which illustrates how we can help reduce certain diagnostic barriers to ensure patients have access to genetic information.”
Invitae’s genetic test for SMA looks for deletions and other lesions in the SMN1 gene which could be helpful for confirming SMA diagnosis. In addition, the genetic test also determines the copy number of the SMN2 gene, which can help inform how the disease will progress and what outcomes are most likely for that patient. According to Invitae, patients with suspected SMA are often unable to commence treatment until a genetic diagnosis is confirmed.
The availability of the SMA genetic test could also boost sales of Biogen’s Spinraza (nusinersin), which is currently the only treatment available for this neuromuscular disease. Approved by the FDA in 2016, sales of Spinraza have been leveling-out due to the fact that 40 percent of all SMA patients taking the drug are currently on the less-expensive maintenance doses.
Patients with SMA display a number of symptoms, including atrophy of skeletal muscles, degeneration of neurons in the spinal cord and weakness of the arms and legs. These symptoms are often the result of a lack of survival motor neuron (SMN) protein – encoded by the SMN1 gene – in motor neurons.
When the SMN1 is mutated and production of the vital SMN protein is impaired, a protein produced by the SMN2 gene can partially make up for this deficit. Patients with more functional copies of the SMN2 gene often have better outcomes, though overall disease severity is influenced by a number of factors.
Invitae will open their SMA Identified program to multiple groups of patients in the US and Puerto Rico, including those who may have SMA based on their symptoms, or have been formally diagnosed but have never undergone genetic testing. The company says that their SMA diagnostic could also be helpful for those with a family history of SMA as well as individuals who are related to SMA patients who have had a genetic test.
Biogen is providing financial support to allow Invitae to offer their genetic testing services for free, however the biotech company will not “receive identifiable patient information” as a result of their partnership. But since Biogen’s Spinraza is the only FDA-approved treatment option for SMA patients, those diagnosed with the neuromuscular disease through the SMA Identified program will likely be treated with the drug.