Martin Shkreli has been fired as chief executive from the drug company KaloBios Pharmaceuticals.
It comes just days after his arrest by the FBI for securities fraud.
In a short statement, the company said he had also stepped down voluntarily from the board.
Mr Shkreli, who came to prominence after his company raised the price of a lifesaving HIV drug by 5,000%, has pleaded not guilty to the fraud charges.
He has already resigned as head of the company which made the drug, Turing Pharmaceuticals.
The FBI has accused Mr Shkreli of using assets from his former company, Retrophin, to illegally pay off debts at MSMB, the hedge fund he managed.
He was released on $5m (£3.53m) bail.
Mr Shkreli has said his arrest was due to his decision to raise the price of Daraprim- a drug used to treat HIV.
In September, Turing increased the price of a Damaprim pill from $13.50 to $750.
Mr Shkreli has defended his actions and been outspoken about his decision to raise the price on social media.
He told the Wall Street Journal that he felt the government was out to get him for "teasing people on the internet" and that his arrest was part of a "social experiment".
On Sunday his Twitter account was hacked and the name was changed to 'Martin the God'.