NEW YORK (Reuters) - Former drug executive Martin Shkreli plans to hire new legal counsel to represent him against U.S. charges that he defrauded investors at his former hedge fund and a pharmaceutical company he headed, Shkreli’s current lawyers said.

Martin Shkreli, chief executive officer of Turing Pharmaceuticals and KaloBios Pharmaceuticals Inc, departs U.S. Federal Court in New York December 17, 2015. REUTERS/Lucas Jackson

Defense lawyers from the law firm Arnold & Porter said in court papers filed on Monday in Brooklyn federal court that Shkreli indicated he wished to replace them and was in the process of retaining new lawyers.

The reason for the lawyer switch was not known. The lawyers did not cite a reason and could not immediately be reached on Tuesday. Shkreli also could not immediately be reached.

Shkreli, who sparked a public uproar last year after he drastically raised the price of a life-saving prescription drug, has maintained a combative stance since his arrest last month on fraud charges.

He frequently posts to Twitter, and in media interviews, including one on Sunday with television station WNYW, has said federal prosecutors unfairly targeted him with a “fictitious” case.

A spokeswoman for prosecutors declined to comment.

Shkreli pleaded not guilty last month to charges that he ran his companies like a Ponzi scheme, using each subsequent company to pay off defrauded investors from a prior company. After his arrest, he stepped down as chief executive of Turing Pharmaceuticals and was fired as chief executive of KaloBios Pharmaceuticals. KaloBios also filed for bankruptcy.

A hearing in Shkreli’s case is scheduled for Wednesday, but the change in lawyers should mean a delay, the Arnold & Porter lawyers said.

“We respectfully request a two-week continuance of the scheduled conference so that Mr. Shkreli can finalize his engagement of new counsel and we can properly transition the matter to the new attorneys,” wrote the lawyers, Marcus Asner and Baruch Weiss.

The case is U.S. v. Shkreli, U.S. District Court for the Eastern District of New York, No. 1:15-cr-637.