The CEO of a pharmaceutical company, which increased the price of a drug used for parasite infections by more than 4,000 percent, said the company would substantially lower the price.

Martin Shkreli, the CEO of Turing Pharmaceuticals, told ABC News they will lower the price days after making headlines and getting complaints from medical groups and others online.

“We’ve agreed to lower the price on Daraprim to a point that is more affordable and is able to allow the company to make a profit, but a very small profit,” he told ABC News. “We think these changes will be welcomed.”

The drug called Daraprim is used to treat parasitic infections that most often occur in those with compromised immune systems due to cancer treatments or HIV infection, and it was sold for $18 per tablet before production rights were acquired by Turing Pharmaceuticals. The company is currently selling the medication for $750 per tablet -- an increase of more than 4,000 percent.

Shkreli and Turing Pharmaceuticals made headlines this week due to the price increase leading to medical groups and others online complaining the company was making money on patients who need the medication.

In a statement released before Shkreli's announcement, the company said that it is aiming to create new medications to treat the disease in an effort to reduce side effects and that the higher price will help subsidize costs for developing new drugs.

"There have been no significant advances or research into this disease area in decades," the company said in a statement. "For toxoplasmosis and other critical, under-treated diseases, the status quo is not an option. Turing hopes to change that by targeting investments that both improve on the current formulation and seek to develop new therapeutics with better clinical profiles that we hope will help eradicate the disease."

The company also said that it would work with hospitals or patients on a case-by-case basis so that everyone can afford the medication. For privately insured patients, it said it would create a co-pay assistance program. In an interview with ABC News today Shkreli defended his company’s actions.

“I think they have a fundamental misunderstanding of the way pharmaceutical companies operate,” he told ABC News of critics. “At this price, Daraprim is not a substantially profitable drug.”

Prior to Shkreli’s announcement, medical groups wrote to the company expressing their worries with the current price. The Infectious Diseases Society of America and the HIV Medicine Association released a joint statement earlier this week calling the prices "unjustifiable.”

"Pyrimethamine (Daraprim) is currently part of the recommended first line treatment regimen for toxoplasmosis in HIV-infected patients and is a critical component of most of the alternative regimens," the groups said in the statement. "This cost is unjustifiable for the medically vulnerable patient population in need of this medication and unsustainable for the health care system."

Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center, said the disease can be acquired from cats and most often leads to symptoms in immunocompromised patients or pregnant women. It's a relatively rare disease that can be hard to treat and can cause swelling in the brain, he explained.

"It's different than average bacterial infection. It requires more prolonged therapy, in part because it's a parasite and they're harder to treat," Schaffner said. "Their bodies can't fight off this infection. We treat longer ... about 3 or 4 weeks."

Before Shkeil announced the company would lower the price, Schaffner said he was concerned doctors would look to use other drugs for treatment before starting Daraprim.