On Friday, Turing Pharmaceuticals CEO Martin Shkreli appeared on Fox Business to defend his company's 5,000 percent price hike of Daraprim, a lifesaving drug that Turing acquired in September.

Shkreli also spoke about his ongoing feud with Democratic presidential candidate Bernie Sanders, who condemned the former hedge fund manager for failing to follow up on his promise to lower the price of Daraprim. Earlier this month, Shkreli posted a series of memes and messages on Twitter criticizing Sanders' policy proposals on Twitter.

"I think he's a demagogue," Shkreli said of Sanders. "He'll say anything to get a vote. And you know, for me to be his piñata is unacceptable."

Shkreli also took to Twitter and challenged Sanders to a public debate on the pharmaceutical industry. In an attempt to arrange a private meeting with the Vermont senator, he donated $2,700, the maximum individual contribution, to Sanders' campaign. But Sanders rejected the donation; instead, he gave the money to an AIDS clinic in Washington D.C.

"Now I donate millions of dollars to charity, and most young entrepreneurs don't do that," Shkreli said. "And ultimately, I think that Bernie has a lot of great ideas, but if he wants to talk about pharmaceuticals, he can do that with me, and he's refusing to do that because I think he's afraid of the issues."

"I think I'd destroy him in any debate about pharmaceuticals."

During the interview, Shkreli said he'd just offered to donate $50,000 to the AIDS clinic where Sanders' campaign sent the pharmaceutical executive's contribution. He complained that Sanders chose to donate his contribution without his permission.

A representative for Sanders campaign had told the Boston Globe that they would not be "keeping the money from this poster boy for drug company greed."

Nearly a month after the Turing CEO told ABC News that he would lower the price of Daraprim, in response to the widespread public backlash, he's yet to do so. Sanders issued a statement saying, "[o]n behalf of the American people we are sickened by these actions."

"Mr. Shkreli is holding hostage the patients who rely on this lifesaving medication, as well as the hospitals that administer it, by charging unconscionable prices for a drug on which he has a monopoly just because he can."