When  risdiplam was approved by the FDA on August 7, 2020, the FDA announced it had also awarded a Rare Pediatric Disease Priority Review Voucher.  These vouchers are tradable, and have a value of roughly $100 million.

The FDA granted this application fast track designation and priority review. The drug also received orphan drug designation, which provides incentives to assist and encourage drug development for rare diseases. The application was awarded a Rare Pediatric Disease Priority Review Voucher.

https://www.fda.gov/news-events/press-announcements/fda-approves-oral-treatment-spinal-muscular-atrophy