BALTIMORE (WJZ) — Major backlash after a pharmaceutical company raised the price of a life-saving drug by more than 4,000%. The CEO is now promising to lower that increase but a Maryland congressman is calling for an investigation.

Meghan McCorkell has the details.

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That increase has caused national outrage and accusations that drug companies are taking advantage of the sick.

It’s a drug used to treat some infections in cancer and HIV patients, but overnight the price for one tablet of Daraprim went from $13.50 a pill to $750.

“The drug was unprofitable at the former price so any company selling it would be losing money. At this price, it’s a reasonable profit—not excessive at all,” said Martin Shkreli, Turing Pharmaceuticals CEO.

Shkreli is facing major backlash, but on Twitter, when asked how he sleeps at night, he wrote, “You know…Ambien.”

His company is now being accused of price gouging.

“It’s predatory practice and it’s inappropriate and we have to take a stand,” said oncologist Dr. David Agus.

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Maryland Congressman Elijah Cummings has been investigating skyrocketing drug costs for years.

“If we can’t take care of Americans when they’re going through illness, if we can’t make sure that they’re not taken advantage of, we need to go home and do something else,” Cummings said.

In a letter obtained by WJZ, Cummings is pushing for the Turing CEO to be called in front of Congress to answer for the price increase.

But Turing’s not alone. Since 2008, non-generic prescription drug prices have soared 127%.

“I have had at least two patients who could not afford their drugs and decided to go the hospice route,” said oncologist Dr. Ram Trehan in 2012.

Still, Turing’s CEO says he’s trying to maintain a successful business. Now he may have to answer to lawmakers.

Again, Turing now says they will roll back that price increase but he hasn’t said how or when.

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At this point, the FDA does not have any authority over drug prices.