The most expensive medicine in the world

So what is the world's most expensive single-dose drug? It's Zolgensma (generic name: onasemnogene abeparvovec-xioi), a life-saving gene therapy approved in May 2019 to treat pediatric Spinal Muscular Atrophy (SMA).

Zolgensma's total cost is $2.125 million, according to Novartis, the manufacturer. It's considered the world's most expensive single-dose drug. But over a lifetime, Biogen's SMA drug Spinraza (nusinersen) actually costs much more. Spinraza can cost $4 million over a period of 10 years as it is not given as a one-time drug.

SMA is a rare genetic motor neuron disease that results in problems with breathing, holding up your head, and swallowing. The majority of children with SMA do not survive past early childhood due to an inability to breathe.

Zolgensma is given as a one-time intravenous (IV) dose. It works by replacing the defective or missing survival motor neuron 1 (SMN1) gene, and is considered potentially curative.