Gov. JB Pritzker signed a bill into law Friday that places guardrails on a drug discount program that hospitals and other healthcare providers say they rely on to help them care for vulnerable patients.

The new law prohibits drugmakers from restricting the number or types of pharmacies that hospitals and other providers can contract with to dispense medications to their patients through a federal program called the 340B Drug Pricing Program. It also bars drugmakers from placing certain other restrictions and requirements on providers and pharmacies participating in the program.

The new Illinois law, called the Patient Access to Pharmacy Protection Act, safeguards “Illinois patients’ access to high-quality, affordable care,” a spokesperson for the governor’s office said in a statement Friday.

“This legislation strengthens protections for healthcare providers participating in the federal program and preserves access to lower-cost prescription medications through the safety-net providers that millions of Illinoisans rely on,” the spokesperson said in the statement.

Under the federal 340B program, drugmakers provide outpatient medications at a significant discount to certain healthcare providers, including those that serve large numbers of low-income patients.

The idea behind the program is to help healthcare providers expand services using the money they save and pass the medication savings on to patients.

But drug manufacturers argue that the savings are not being passed along to patients, and that hospitals and others are instead profiting from the program.

“Large tax-exempt hospitals and their for-profit partners are exploiting the program, buying medicines at steep discounts and then marking them up by thousands of dollars,” Will May, a spokesperson for industry group the Pharmaceutical Research and Manufacturers of America, said in a statement.

“Across the country and here in Illinois, 340B is driving up costs for patients, taxpayers and employers instead of ensuring that these savings reach those who need them most,” May said in the statement.

Meanwhile, healthcare providers are praising the new Illinois law, saying they rely on the money saved through the program to help them care for patients in need.

“These protections have real consequences for real patients,” Ollie Idowu, president and CEO of the Illinois Primary Health Care Association, said in a news release. “They mean health centers can continue helping patients access affordable medications while reinvesting 340B savings into expanded services, workforce development, chronic disease management, behavioral health care, and other critical programs that improve health outcomes.”

The Illinois Health and Hospital Association also backed the bill.

The governor also signed a bill into law Friday requiring the Illinois Department of Insurance to study how healthcare providers and pharmaceutical companies participate in the 340B program.

“Increased transparency is needed to ensure that vulnerable communities receive the benefits intended from the Patient Access to Pharmacy Protection Act,” according to the legislation.