NEW YORK (TheStreet) -- Biotech CEOs are supposed to be cheerleaders, so it's noteworthy when a CEO's pocketbook indicates otherwise.

Case in point: PTC Therapeutics (PTCT) - Get Report CEO Stu Peltz no longer owns his company's stock. Peltz sold his remaining 47,200 shares in the orphan disease drugmaker on Monday, according to an SEC filing.

Insider selling isn't necessarily unusual, and in Peltz's case, the PTC shares were sold under a 10b5-1 pre-arranged stock trading plan. But Peltz didn't just sell some PTC stock, he liquidated his position in the company he runs.

Peltz "maintains a very significant investment in PTC through his stock options, which is the primary method utilized by PTC for equity compensation," a company spokesperson said. 

The timing of Peltz' sales also come at a sensitive time for the company. PTC is conducting a Phase III study of its lead drug ataluren in patients with Duchenne muscular dystrophy caused by "nonsense mutations." Results from the ataluren study are expected in the fourth quarter, a huge binary event for PTC. Positive study results will almost certainly lead to a U.S. approval of ataluren and will secure a final approval in Europe, where the drug is already marketed on a conditional basis.

Peltz also sold all his PTC stock weeks after a market rumor in late February had the company being shopped around for a sale, possibly to Shire (SHPG) - Get Report, Biomarin Pharmaceuticals (BMRN) - Get Report or Vertex Pharmaceuticals (VRTX) - Get Report.

The PTC takeout rumors fueled a big jump in the company's stock price from the mid $50s to the low $70s per share. Peltz's insider sales Monday and another sale earlier this month benefited from the higher share price caused by the rumor.

Other PTC executives also sold company stock following the takeout rumor.

PTC shares were down 1% to $68.22 in trading early Tuesday.

Adam Feuerstein writes regularly for TheStreet. In keeping with company editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback; click here to send him an email.