Drug companies and hospitals are gearing up for a big battle on Capitol Hill over the future of the 340B Drug Pricing Program, the 25-year-old program aimed at helping hospitals serving low-income communities.

The program, which was signed into law by President George H.W. Bush, requires pharmaceutical companies to offer discounts on drugs to hospitals that serve a disproportionately large number of low-income patients. Medicare in turn reimburses the hospital for the market rate of the drug plus 6 percent.

The idea behind the program is that the hospital will use the surplus from the Medicare reimbursement to invest in other critical needs. However, critics have alleged that there is little accountability over the use of the extra money and that hospitals may very well be using it merely to pad salaries or profits.