The current CEO of drug company Retrophin likened its ousted chief Martin Shkreli to the “Pied Piper” Thursday as he testified in his Ponzi scheme trial — calling him “brilliant” but “dishonest.”

“One of my senior managers once described him as the Pied Piper,” Stephen Aselage said of Shkreli, 34, who is accused of using unauthorized Retrophin funds to pay off his hedge fund investors after he lost their money in a bad trade.

“He just sings a song and everyone wants to follow him.”

Aselage’s comments came after Brooklyn federal prosecutors asked him why he didn’t leave the company upon discovering Shkreli had been engaging in “dishonest” practices.

“He was very energetic, bright, enthusiastic — he could break down walls to make things happen,” Aselage said. The 66-year-old took over Shkreli’s post at Retrophin, which Shkreli founded, after the “Pharma Bro” was pushed out by board members.

Prosecutors and witnesses contend Shkreli used investments in his hedge fund, MSMB Capital, to bolster his new drug company without investors’ knowledge.