Updated: June 14, 2019 / 3:26 p.m.

On Friday, U.S. drugmakers filed a lawsuit that challenges a new government regulation requiring drug manufacturers to disclose the list price of prescription drugs in direct-to-consumer television advertisements.

The lawsuit was filed jointly by the companies Amgen Inc, Eli Lilly, Merck & Co, and Co and the Association Of National Advertisers in the U.S. District Court for the District of Columbia.

The new regulation that was finalized on May 8 by the U.S. Department of Health and Human Services (HHS) and is set to take effect in July. It is part of the government’s efforts to lower the cost of prescription medications for U.S. consumers.

Drugmakers have disputed over the new regulation, claiming that the list prices do not signify the final price that is paid by the consumer, as it excludes rebates and discounts drugmakers may offer to the customer, as well as patient assistance programs to make drugs more affordable.

“Not only does the rule raise serious freedom of speech concerns, it mandates an approach that fails to account for differences among insurance, treatments, and patients themselves, by requiring disclosure of list price,” Amgen mentioned in a statement.

“Most importantly, it does not answer the fundamental question patients are asking: ‘What will I have to pay for my medicine?’” Amgen said.

As of now, It remains to be seen whether or not the advertising regulation would have any impact on lowering costs if the requirement goes into effect.

“If the drug companies are embarrassed by their prices or afraid that the prices will scare patients away, they should lower them,” HHS spokeswoman Caitlin Oakley mentioned in an emailed statement.

“President Trump and Secretary Azar are committed to providing patients the information they need to make their own informed healthcare decisions.”