When does Big Pharma profiting become profiteering? This issue was the subject last month of a Senate Finance Committee investigation of pricing practices of Gilead Sciences Inc., a leading provider of hepatitis C medications. After examining 20,000 pages of internal company documents, looking at Medicaid data and interviewing health care experts, the authors concluded that the Foster City drugmaker "pursued a calculated scheme for pricing and marketing its hepatitis C drug based on one goal: maximizing revenue regardless of the human consequences." With the hepatitis C virus affecting about 3 million people in the United States, the impact of Gilead's pricing strategy is real, measurable - and devastating. With a 12-week course of Gilead's Harvoni priced at nearly $100,000, taxpayer-funded Medicare Part D spent $4.6 billion on hepatitis C alone in the first half of 2015. When insurers refuse to pay for treatment, all but the wealthy are left at risk for cirrhosis, liver cancer and death. While anticipating record profits of $30 billion in 2015, Gilead virtually eliminated its medication assistance program. More than 90 percent of hepatitis C patients can achieve a cure with as little as one pill a day. But to realistically address this epidemic at current pricing levels would bankrupt our health care system. Pharmaceutical innovation holds great promise for the future of our health care system. But not if none of us can afford it.