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Do Ligand Pharmaceuticals (LGND -8.05%), Emergent BioSolutions (EBS -2.10%), or ANI Pharmaceuticals (ANIP -1.37%) sound familiar?

Probably not. But just because these three sleeper stocks haven't gotten a lot of love (yet!) from Wall Street, that doesn't mean they aren't worth looking at.

After all, biotech is full of hyped-up companies that burn through hundreds of millions of dollars and end up with nothing to show for it. By contrast, these companies are all kind of like ordinary-looking stock commuter cars that are anything but boring under the hood. Take a peek inside, and you'll see why they could give much better-known biotechs a real ego-bashing challenge next year. Each is equipped with multiple successful product lines, highly diversified revenue streams, and downright exciting growth prospects. While biotech investing is the definition of high-risk, our contributors believe each may be poised to offer investors a nice ride in 2016. Read on to find out why. 

Keith Speights: In football, quarterbacks and running backs get most of the glory, but it's the offensive line that makes their success possible. Ligand Pharmaceuticals (LGND -8.05%) is the equivalent of an offensive lineman in the biotech world.

Ligand doesn't get nearly as much press as many similar-sized biotechs. However, the stock has almost doubled in 2015 -- thanks primarily to helping make other drugmakers successful. Many of the biggest names in the biotech and pharmaceutical industry use Ligand's Captisol technology, which improves the solubility and stability of drugs. Ligand also counts seven drugs on the market through partnerships with other companies, most notably Promacta, Kyprolis, and Duavee.

Don't be fooled, however, by the company's seemingly low earnings multiple, which currently stands below 9. That figure is heavily skewed by a net income tax benefit of $217.3 million posted in the third quarter. In reality, Ligand's stock isn't valued at such a discount. However, the company's growth prospects are strong and make this an unheralded biotech that investors might want to consider.

Cheryl Swanson: Emergent BioSolutions is one biotech you have to hope always remains under the radar, but that doesn't mean it's not a potentially great stock. The company has a maximum $1.5 billion contract to supply the U.S. national stockpile of anthrax vaccines -- one of the first lines of defense against a bioterrorist attack.

It's Emergent's strategic moves, not any bioterrorist threats, however, that make it worthy of investor attention. Emergent is plotting to split in two, keeping its lucrative work in biodefense under its old name and forming a new company, Aptevo Therapeutics, to run with its biosciences pipeline. Aptevo should launch midyear 2016 through a tax-free spinoff of shares, much as Baxter did with Baxalta.

Emergent's sales jumped last quarter to $124 million, 47% higher than the same quarter in 2014, and the company is continuing to rapidly expand its stable of products. It bagged FDA approval for post-exposure treatment Anthrasil earlier this year, and, at the end of November, the FDA approved a broadened use of the company's core product, BioThrax. The approvals, coupled with the government's plan to stockpile Anthrasil, give Emergent more cash to fund its promising phase 3 drug for hemophilia B, phase 2 antibody for leukemia, and early stage prostate cancer treatment.

Sean Williams: Profits are incredibly hard to find with any consistency within the biotech sector, but Minnesota-based drug developer ANI Pharmaceuticals could give investors quite the surprise.

ANI Pharmaceuticals is one of a very select few hybrid drug developers. It develops or acquires branded drugs that carry juicy margins, and it also boasts a portfolio of generic drugs, which swoop in when periods of patent exclusivity have expired for brand-name drugs. Generic drugs often have lower margins because of their much lower price point than branded drugs, but sheer sales volume usually makes their manufacture and research worthwhile. Approaching its development from both sides of the aisle (branded and generic) gives ANI Pharmaceuticals a way to both hedge against patent losses from its own product portfolio and to take advantage of other drug developers' misfortunes.

As it stands now, ANI Pharmaceuticals has 14 products on pharmacy shelves, including generic versions of Oxycodone and Vancomycin, and a pipeline that consists of 85 drugs, which, according to CEO Arthur Przybyl, "represent over $4.6 billion in IMS sales." In the third quarter, reduced sales of acid-reflux drug Reglan sent branded pharmaceutical sales down 53% to $2.3 million, but 48% growth in generic sales to $15.1 million helped total sales rise 15% year over year. Operating income also inched higher by $0.3 million to $8.5 million.

Looking ahead, you can probably expect ANI to emphasize its generic portfolio while looking for ways to purchase growth for its branded and/or generic portfolio. If Wall Street's estimates are correct, ANI Pharmaceuticals could generate in excess of $8 in EPS by 2018. For context, the company earned just $1.14 per share last year. That alone makes this an under-the-radar biotech worth watching.