Former drug company executive Martin Shkreli arrives at U.S. District Court for the third day of jury deliberations in his securities fraud trial in the Brooklyn borough of New York City, U.S., August 2, 2017.
Former drug company executive Martin Shkreli arrives at U.S. District Court for the third day of jury deliberations in his securities fraud trial in the Brooklyn borough of New York City, U.S., August 2, 2017. Reuters / AMR ALFIKY

The law firm that defended Martin Shkreli against antitrust charges said it has not been paid, and on Tuesday asked a U.S. judge for permission to withdraw from representing the former pharmaceutical executive best known for hiking the price of a lifesaving medication more than 40-fold.

Duane Morris LLP said Shkreli's former company Phoenixus AG agreed to cover his legal fees but has refused to pay the $2.04 million owed through March 31, after exhausting the limits of an insurance policy covering the fees in October.

In a filing in Manhattan federal court, Duane Morris also said Shkreli "has no assets" to pay its fees, and would not be harmed if it withdrew because the antitrust trial is over. The law firm said Shkreli did not oppose its withdrawal.

Lawyers for Phoenixus did not immediately respond to requests for comment.

Shkreli, 39, became known as "pharma bro" after raising the price of the anti-parisitic drug Daraprim overnight to $750 per tablet from $17.50 in 2015, and appearing unrepentant when criticized.

In January, U.S. District Judge Denise Cote in Manhattan banned Shkreli from the drug industry for life and ordered him to pay $64.6 million, finding he illegally sought to keep generic Daraprim rivals off the market.

The case had been brought by the U.S. Federal Trade Commission and seven U.S. states.

Shkreli is serving a seven-year prison sentence after being convicted in 2017 of defrauding investors in two hedge funds he ran and scheming to defraud investors in another company.

He is eligible for release on Nov. 7.

In February, the Brooklyn judge who oversaw the criminal case and a related U.S. Securities and Exchange Commission civil case permanently banned Shkreli from serving as an officer or director of public companies.