Shares of Valeant Pharmaceuticals tumbled on Tuesday after the company cut its 2016 revenue forecast by about 12 percent and said a delay in filing its annual report could pose a debt default risk.
The stock closed down more than 51 percent on Tuesday.
One of its big investors, Bill Ackman, said he is still confident in Valeant and he plans to be more proactive in his dealings with it. However short seller Andrew Left of Citron Research told CNBC's "Fast Money" on Thursday that the price drop in Valeant is a reflection of the problems with the company's business model.
"If you look at what we saw today, really it was an unwind of the whole platform strategy, how Valeant goes about repairing their business. ... How are they going to make these franchises more valuable than when they acquired them without having to raise prices? That's obviously difficult," Left explained.