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The biotechnology industry is chock-full of risky stocks, but that doesn't mean conservative investors should ignore it entirely. You might be surprised to find that more than a few biotech stocks with market-beating potential fit your risk profile.

Plenty of biotechnology companies enjoy steadily increasing profits that are poised to continue growing. Meanwhile, the market has hammered the industry across the board, which makes the present a great time for cautious investors to buy some great stocks at a nice price. To help sift through a plethora of biotech names, we asked three Motley Fool contributors to highlight one company positioned for long-term gains.

Here are their favorites:

Safety through diversity

Keith Speights: How can investors lower risk? Probably the best answer to that question is: by diversification. Usually when we talk about diversification, we refer to buying multiple assets or multiple stocks that aren't highly correlated. But can investors achieve a level of diversification with just one stock? I think it's possible -- and the stock I believe can deliver on this goal is Ligand Pharmaceuticals (LGND -1.34%).

Ligand currently has 11 products on the market, with Kyprolis and Promacta generating the most revenue. But look at the company's pipeline and you'll see why Ligand provides a measure of diversification for investors.

Three drugs that use Ligand's proprietary technologies are awaiting regulatory approval. Another eight drugs are in late-stage development. Ligand counts 21 phase 2 clinical studies underway. The company has the same number of drugs using its technologies in early-stage testing. That's a grand total of 64 drugs, targeting a wide variety of indications, that are either on the market, waiting to be approved, or in clinical development -- that's more more than a number of the biggest biotechs on the planet can claim.

Ligand pulls off this diversification by partnering with over 60 companies. Half of its partners are biotechs, and nearly one-fifth are big pharma. Name a prominent drugmaker and there's a good chance that it uses Ligand's technology. 

As you might expect with so many drugs in the pipeline, Wall Street forecasts pretty serious earnings growth for Ligand in the future. The average estimate is for the company to increase earnings by nearly 46% annually over the next five years.

Multiple ways to win

Brian Feroldi: I think that even conservative investors could learn to love Amgen (AMGN 0.11%). This company has grown by leaps and bounds over the past few decades, and it's no exaggeration to call it one of the most important healthcare companies in the world today.

Amgen's past success can be traced to a handful of blockbuster drugs, most notably Neupogen and Epogen. Fast forward to today, and the company has more than a dozen products on the market generating revenue, with many of them growing quickly. In the first quarter, sales of Enbrel, a top-selling autoimmune-disease drug, jumped 24% year over year. Kyprolis, a cancer medicine (and mentioned above!), showed an even more impressive growth rate of 43%. Nine of Amgen's drugs grew by double digits, while total revenue growth came in at 10%.

There are plenty of reasons to believe that the growth will continue in the years ahead, too. Right now Amgen's new cholesterol drug, Repatha, isn't contributing very much to the company's success, but that could change in a hurry if data from a long-term cardiovascular study shows that Repatha helps lower the risk of a heart attack or stroke. Investors should have that data before the end of the year, and if it goes well, Repatha could eventually pull in north of $2 billion in revenue each year.

Amgen is also pushing hard to become a big player in the up-and-coming biosimilars market. The company has built out an impressive array of drug candidates that hold potential to steal market share away from a few megablockbuster drugs like Avastin, Humira, and Herceptin. Indeed, Amgen offers investors multiple ways to win from here.

I think that conservative investors will also appreciate that Amgen has turned into an income stock as well. The company currently pays out an annual dividend of $4 per share, which at current prices translates into a yield of roughly 2.5%. Even at this level, the dividend consumes roughly 40% of Amgen's earnings, which means that there is still plenty of room left for the company to boost its payout.

Overall, Amgen really is the complete package. It's growing, it pays a solid dividend, and it's trading for only about 13 times next year's earnings. That's a combination that any investor can learn to love.

Profitable and cheap

Cory Renauer: I'm no fan of risk, but biotech stock United Therapeutics (UTHR -0.01%) suits me just fine for several important reasons. First, the company has proven it can successfully launch new drugs into a small niche. Pulmonary arterial hypertension (PAH) is a rare, life-threatening disease in which the arteries leading to the lungs from the heart become too narrow.

United Therapeutics has three versions of the drug treprostinil, a synthetic version of a natural vasodilator, on pharmacy shelves for PAH patients at different stages of the disease. Remodulin is delivered by infusion and is indicated for advanced-stage patients, Orenitram is an extended-release pill, and Tyvaso is administered by inhalation.

In the first quarter of 2016, United Therapeutics' total revenue rose 12.7% from Q1 2015, to $369 million, but sales of leading products Remodulin and Tyvaso contracted by 4.4% and 9.9% respectively. Although sales for United Therapeutics' products have grown steadily for years, recent market entrants from Bayer and Actelion for treatment of PAH have the market spooked.

UTHR Chart

UTHR data by YCharts.

As you can see in the chart above, this isn't the first time the stock has tumbled ahead of continually rising sales, and the latest thrashing has reduced the price to just six times trailing earnings. If sales continue to grow at their present pace, investors could see big gains. More important for cautious investors, if United Therapeutics simply treads water, you'll probably still come out ahead over the long run.

I'm expecting growth, as cash flows from its PAH lineup have been successfully used to buy growth. For example, the company purchased U.S. commercialization rights for Adcirca from Eli Lilly for $150 million up front in 2008, and the drug is on pace to reach about $300 million in sales for United Therapeutics this year.

Last year, the company's Unituxin won approval for treatment of a rare pediatric cancer, neuroblastoma. The approval earned United Therapeutics an FDA priority review voucher, subsequently sold to AbbVie for $350 million, and Unituxin finished the first quarter on pace to reach about $60 million in sales this year.

But United Therapeutics hasn't used all its resources to acquire growth. It's been repurchasing shares at a rapid pace, reducing the number outstanding by about 20% over the past five years. That means a larger slice of future profits will go to each share, something we conservative investors appreciate.