Marketed by Biogen and increasingly available worldwide, Spinraza is the first approved treatment in China for SMA, a disease that results in progressively debilitating muscle weakness. The news marks a pivotal moment in China’s efforts to expand access to medical treatments, particularly for rare diseases such as SMA.
The therapy is specifically indicated to treat 5q SMA, which represents roughly 95 percent of all SMA cases.
“We commend China’s regulatory authorities for their expedited review and approval of Spinraza, the first and only treatment for SMA,” Michael Vounatsos, Biogen’s CEO, said in a press release. “SMA is the most common genetic cause of infant mortality and a major cause of disability in adults. We are working diligently with the government agencies, patient groups and physicians who all have an incredible sense of urgency to expand access to a broad group of patients in China.”
Approval was based on the largest set of clinical data available on the disease, including more than 300 patients with infantile and more-advanced SMA. An ongoing open-label, global Phase 2 clinical trial (NCT02386553), called NURTURE, showed groundbreaking effectiveness in pre-symptomatic patients up to 6 weeks old. Evidence demonstrated that early treatment of such infants progressively helped motor function.
Results from a Phase 3 trial (NCT02193074), called ENDEAR, also showed that those treated with Spinraza had improvements in achieving motor milestones compared with untreated study participants.
“This is great news,” said Yi Wang, head of the National Rare Diseases Group of the Chinese Pediatrics Society, Chinese Medical Association. “These improvements provide new hope to the community where there previously were no approved treatments. As the first approved therapy for SMA in China, Spinraza is a breakthrough within the rare disease space. The clinical treatment for SMA is entering a new historic stage.”
Last May, the China National Health Commission (NMPA) added SMA to the country’s first list of rare diseases, which was created to aid in the diagnosis and treatment of rare disorders. Two months later, the NMPA announced that new treatments supported by clinical results from advanced-market trials would be assessed through a priority review process. Evaluations were previously limited to clinical trials and research conducted within China.
The NMPA is responsible for creating and supervising the implementation of policies, plans, and standards governing the quality of drugs, cosmetics, and medical devices in China.
In September, the NMPA accepted Spinraza for priority review as a clinically urgent new treatment that has already been approved for nearly all types of SMA by a growing roster of countries including the United States, the European Union, Australia, Brazil, Japan, Switzerland, South Korea, Canada, and Chile. It’s under review by Britain’s National Institute for Health and Care Excellence. And NHS Scotland will cover Spinraza injections at low or no cost for all of its SMA patients starting in April, while it continues to collect more information on its effectiveness.
By the end of last year, more than 6,600 patients were being treated with Spinraza around the world, according to Biogen. Affecting up to 1 in 10,000 live births, SMA is caused by a mutation in the survival motor neuron 1 gene (SMN1). In healthy individuals, this gene produces a protein called the survival motor neuron (SMN), critical to the function of nerves that control muscles. Without sufficient levels of SMN protein, motor neurons in the spinal cord are lost, preventing muscles from receiving brain signals.
Another closely related gene, SMN2, is not believed to be affected in SMA, but does not create enough functional SMN protein on its own. By targeting the SMN2 gene, Spinraza, an antisense oligonucleotide, is able to produce more full-length SMN proteins.