Thanks to the extensive research, SMA now has the following two approved treatments:
Nusinersen, marketed as Spinraza by Biogen, by the USFDA in December 2016, was the first ever drug to treat SMA in both infants and adults. Many developed countries like USA, Europe, Canada, Poland, Australia, etc subsequently approved Spinraza and made it available to its citizens with the help of government and insurance support.
Spinraza works by making the “back-up” gene, the SMN2 gene, function more like the SMN1 gene and produce the fully functional SMN protein. When administered at the early stages of the disease, Spinraza has been observed to have a considerable impact in delaying and even reversing the impact of SMA thereby improving the quality of life of SMA patients considerably.
Spinraza costs US$750,000 in the first year and US$375,000 annually after that in the United States as of 2019.
Onasemnogene abeparvovec, marketed as Zolgensma by a US biotechnology company AveXis, a subsidiary of Novartis, is a gene therapy medication used to treat spinal muscular atrophy (SMA). It got approved by the USFDA in May 2019 to treat infants below 2 years of age. It has trials underway to treat patients above 2 years of age and is expected to reach that milestone in the coming times.
Onasemnogene abeparvovec is a biologic drug consisting of AAV9 virus capsids that have been deprived of the original viral DNA and instead contain a SMN1 transgene along with promoters. The drug is administered intravenously or intrathecally. Upon administration, the AAV9 viral vector delivers the SMN1transgene to cell nuclei where the transgene begins encoding SMN protein, thus addressing the root cause of the disease. Since motor neurons do not divide, it is thought that a single dose of the drug will have a lifelong effect. Zolgensma is priced at US$ 2.125 million per dose (one-time treatment), making it the most expensive medication in the world as of 2019.