The $100,000 drug that costs $100 to make

Pharma companies are notoriously secretive about their production outlays, especially for blockbuster drugs like sofosbuvir, which is set to radically change the treatment of hepatitis C.

However, a UK study has crunched the numbers, estimating that a 12-week course of this phenomenally expensive antiviral costs its manufacturer Gilead just $100 to make.