The FDA Approved The World’s Most Expensive Drug Last Week, A $4.25 Million One-Time Gene Treatment For An Ultra-Rare Nerve Disorder Typically Found In Toddlers

The way the gene therapy works is by reversing the underlying cause of the condition in the brain, adding a missing gene to children’s bone marrow cells.

Most of the kids who received it during trials that began in 2010 have gone on to live relatively normal lives, going to school and playing sports.

Previously, the most expensive drug in the world was a hemophilia treatment called Hemegenix, which is also another gene therapy. It cost $3.5 million.