Yup, went from incredibly painful, unsuccessful and intolerable interferon treatments to a several week course of pills with pretty much zero side effects. The drug companies were able to get it priced it at the cost of administering and managing side effects of prior unsuccessful treatments, to the tune of ~$1+k/pill.

They were making $10B/year although the market is now shrinking. This all happened in the past ~15 years and was pretty amazing to watch. We pretty much don't think or care about Hep C anymore.

There is plenty of money to be made- problem is finding cures is hard. If you find a cure you can't just sit on it because some other company can do the same eventually and steal your moat and make billions.