It hasn't started out as a very happy new year for some investors. That's especially true for shareholders of these three health-care stocks.

Decelerating
Last year, shares of Accelerate Diagnostics (AXDX -0.91%) tripled. This week, though, the stock decelerated rather than picking up steam. Shares fell nearly 17%.

What happened? Nothing. At least, there wasn't any obvious bad news over the past few days for the in vitro diagnostics company. Nonetheless, the stock experienced significant drops on both Tuesday and Thursday (with a break in the action on Wednesday since the market was closed for the New Year's Day holiday).

The pullback presented a buying opportunity, though. And one of the biggest individual shareholders of Accelerate Diagnostics took advantage of it. Larry Feinberg, founder of Oracle Partners, bought more than $1 million in Accelerate Diagnostics shares on Tuesday. 

Sinking like a BRAC
Last year just wasn't a good one at all for Myriad Genetics (MYGN -2.79%). Unfortunately, 2014 isn't looking too hot, either. Shares of the molecular diagnostics company dropped 12% this week.

Technically, this last week's decline stemmed from bad news from last year spilling over to the new year. On Dec. 30, the Centers for Medicare and Medicaid Services, or CMS, announced its proposed Medicare reimbursement for 2014. CMS's recommendations included a whopping 48.6% cut to the BRACAnalysis gene test sold by Myriad. Ouch.

Analysts quickly piled on with more bad news. JMP Securities, Mizuho Financial, and Goldman Sachs all downgraded Myriad. Goldman slashed its price target for the stock by more than 37%. After losing several key patents on its technology in June of last year and now the latest from CMS, it looks like if it weren't for bad luck Myriad Genetics would have no luck at all.

Give and take
The stock market gives -- and the stock market takes away. Shareholders of Inovio Pharmaceuticals (INO -1.48%) got a taste of this maxim over the past few days, with the stock falling nearly 12%.

It was only a week ago that Inovio ranked among the biggest health-care winners, soaring by 32%. Those gains came on no big news stories. There weren't any major developments this week, either, but that didn't keep the stock from losing out.

This type of action is to be expected with Inovio, though. Excitement is brewing over the company's synthetic DNA vaccines, especially one focusing on cervical dysplasia. Institutional investors have been acquiring shares over the last several months, indicating that big money expects big things from this small company. However, it could be a while before Inovio is in position to bring any product to market. 

Hanging on to horrendous
Which of this week's horrendous stocks appears to be most likely to keep on being horrendous into 2014? It's an easy answer this time around. 

Myriad Genetics doesn't look to have any bright spots on the horizon. While the CMS reimbursement cuts aren't final yet, there's no realistic reason to expect the situation will get any better for Myriad. 

As for Accelerate Diagnostics and Inovio, though, the new year could ultimately prove to be a happy one. Investors with deep pockets are banking on success for both of these companies. They could very well prove to be right.