Usage of hepatitis C drugs dropped 40 percent among Medicaid patients in 2015, according to pharmacy benefit manager Express Scripts, and most of that drop occurred in states that cover the drugs in fee-for-service Medicaid instead of letting private plans manage the drugs. There was no competition for Gilead Sciences’ hepatitis C medications -- Sovaldi and Harvoni -- during their first year on the market, and the price of the drug Sovaldi sparked a debate over drug prices that continues...