Health-care has been hot in 2013. Not every stock in the sector has sizzled, though. Here are three of the most horrendous health-care stocks of the year.

A disappointing fish tale
Many investors had high hopes early in 2013 for Amarin (AMRN 1.75%). Those hopes were largely dashed in October, though, after a very disappointing FDA decision. As a result, Amarin is on track to finish the year down a whopping 77%.

Amarin thought that it might be able to gain approval for fish-oil drug Vascepa as a treatment for high triglyceride levels between 200 and 499 mg/dL. Doing so would have presented a new market for the drug around 10 times larger than the already-approved indication for severely high triglyceride levels.

Unfortunately, it was not to be – at least not yet. In October, an FDA advisory committee voted against recommending Vascepa for approval. The FDA subsequently rescinded its Special Protocol Assessment for the ANCHOR clinical study. Amarin is appealing this decision. 

Off the shelf shellacking
Shareholders of Ariad Pharmaceuticals (NASDAQ: ARIA) also felt plenty of pain in 2013. The stock dropped 67% as a result of FDA decisions about leukemia drug Iclusig.

The first decision came in mid-October, after it was discovered that patients taking Iclusig developed serious arterial blood clotting. The next shoe to drop came at the end of the month. This time, the FDA suspended marketing of the drug in the U.S. Ariad's stock reeled from the decisions.

Anyone who thought this meant the end of the line for Ariad and Iclusig got the cart before the horse, though. On Dec. 20, Ariad announced that the FDA gave the green light to put Iclusig back on the market under more restrictive labeling. The stock mounted something of a comeback – but not enough to reverse the major decline already experienced.

Holding back
Our third-worst health-care stock wasn't far behind Ariad. Shares of Achillion Pharmaceuticals (ACHN) sank 61% because of -- you probably guessed it -- a devastating FDA decision.

In Achillion's case, there were actually two FDA decisions that did the damage. The first occurred in June when the agency placed the company's hepatitis-C drug sovaprevir on clinical hold. This decision occurred after elevated liver enzymes were found in patients in an early stage clinical study.

The FDA delivered another blow in September when it upheld the clinical hold. That left Achillion left with "plan B" -- try to get the FDA to remove the hold and move forward with other drugs in the pipeline.

Plan B didn't sound like a good plan to investors, though. Achillion came back somewhat in the fourth quarter, but not even close to regaining the lost ground .

Comeback trail
Can any of this year's horrendous health-care stocks mount a comeback in 2014? Perhaps. All three are already making attempts to do so.

Amarin's appeal hopes have helped the stock move up in December. Ariad's victory in getting Iclusig back on shelves was great news for shareholders. Achillion has moved higher as analysts raised estimates to project lower losses.

The likelihood is that none of these three will make repeat appearances on horrendous lists for 2014. However, don't count on any of these stocks returning to their high marks from earlier this year anytime soon. Horrendous falls require humongous gains to just get back to even.