Martin Shkreli, a former hedge fund manager turned pharmaceutical businessman has attracted a lot of negative attention over the years due to his opportunistic business moves.

Shkreli, 32, has purchased the rights to Daraprim, a very popular 62-year-old drug used for treating life-threatening parasitic infections, and raised its price from $13.50 per tablet to $750 overnight.

Turing Pharmaceuticals, purchased the rights to Daraprim for $55 million on the same day that Turing announced it had raised $90 million from Shkreli and other investors in its first round of financing.

The substance is used for treating toxoplasmosis-a parasitic infection that can cause serious and even life-threatening problems to babies and people with compromised immune systems like AIDS patients and certain cancer patients.

Daraprim’s price has increased to almost 5,500 percent since Shkreli acquired it, making it unreachable for the masses.

Shkreli defended his actions saying that Turing will use the profit to develop better treatments for toxoplasmosis, with fewer side effects.

“This isn’t the greedy drug company trying to gouge patients, it is us trying to stay in business,” Shkreli said.

“Many patients use the drug for far less than a year and that the new price is similar to other drugs used for rare diseases.

“It really doesn’t make sense to get any criticism for this.”

Meanwhile, the outrage on social media following the news led Democratic presidential candidate Hillary Clinton to comment.

“Price gouging like this in the speciality drug market is outrageous,” she tweeted.

“Tomorrow I’ll lay out a plan to take it on. – H.”

Fierce Biotech editor John Carroll also took to Twitter asking Shkreli to explain the unreasonable hike.

“It is a great business decision that also benefits all of our stakeholders,” he replied and slammed Carrol’s comments adding “You are such moron.”

Shkreli has a rather interesting business history. He was still in his 20’s when he started the hedge fund MSMB Capital, and was accused of urging the FDA to not approve certain drugs made by companies whose stock he was shorting.

Furthermore, in 2011, he joined Retrophin, a company which acquired old drugs and re-sold them with raised prices.

Retrophin fired Shkreli last year accusing him of withholding the company’s profitsto repay his hedge fund debts. The case made it to the Federal District Court.

Sources: The Guardian, ABC, Twitter