The nation may have finally met a drug it cannot afford. Sovaldi is a long-awaited breakthrough for the 3 million Americans suffering from the hepatitis C virus. And at $1,000 a daily pill, or $84,000 over 12 weeks of treatment, the medication could generate as much as $19 billion nationwide in revenue in the next three years for maker Gilead Sciences in Foster City. Since Sovaldi won federal approval in December, lawmakers, insurers, pharmacy benefit managers and patient advocates have begun an all-out revolt. The dissent might represent a potential breaking point for a health care regime used to paying out gobs of money for breakthrough drugs, industry officials and analysts say. “The payer community is frustrated to the point to where they believe this could actually break the system,” said Dr. Steven Miller, chief medical officer of Express Scripts Holding Co. in St. Louis, a pharmacy benefit manager that handles more than 1 billion prescriptions in the U.S. Express Scripts recently pressured Gilead to lower the price by asking its clients to stop using Sovaldi once a rival drug is approved. The company pounced after Congress asked Gilead to justify Sovaldi’s cost.