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I can't think of anything better in an international stock than finding a company that's the leader in its field, markets its products to the whole planet, and is unaffected by recessions. There aren't many companies like this in the world, but Danish drugmaker Novo Nordisk (NYSE: NVO) is one of them.

Never heard of Novo Nordisk? That's OK. If you know someone with either type of diabetes, then there's a good chance they're using one of Novo's drugs. Novo Nordisk is the worldwide leader in treating diabetes, which is a disease whose prevalence is unfortunately growing at an amazing rate. The World Health Organization estimates that eight years ago, 171 million people had either type 1 or type 2 diabetes. Today, more than 200 million people have it, and by 2030, this figure will jump to 366 million people worldwide. Needless to say, this presents a huge growth opportunity for diabetes care drugmakers.

Novo Nordisk's insulin and other diabetes drugs are used in the whole range of diabetes treatment regimens for insulin-dependent type 1 diabetes patients to early-stage adult-onset type 2 diabetes, often caused by a sedentary lifestyle and obesity. Novo Nordisk does have tough competitors like Sanofi-Aventis (NYSE: SNY), Eli Lilly (NYSE: LLY), and Merck (NYSE: MRK), but Novo has a stronger and broader diabetes drug product portfolio than these competitors.

In the past couple of years, there have been several innovative diabetes treatments to enter the market, like Merck's Januvia, Amylin Pharmaceuticals' (Nasdaq: AMLN) Byetta, and new ones still in the works like MannKind's (Nasdaq: MNKD) inhaled insulin Technosphere. One thing that none of these drugs fully replaces, though, are Novo Nordisk's rapid-acting insulin analogues and long-lasting insulins.

Even better, Novo is also working on developing compounds in some of these new classes of diabetes therapies like GLP-1 analogues and will benefit from the evolution in diabetes care. Novo isn't just focused on treating diabetes. It markets other drugs, like uncontrolled bleeding treatment NovoSeven, has a modest biopharmaceuticals pipeline, and is also testing some of its diabetes treatments in new indications like obesity.

Novo's shares can be bought as an American depositary receipt (ADR) on the New York Stock Exchange, so there's no hassle in dealing with foreign stock exchanges. Even better, since Novo is located in Denmark, investors get to benefit from any weakening of the dollar as the price of the ADR adjusts upward to account for these currency moves.

In Novo's just-announced year-end financials, sales were up 13% in 2007, net income spiked 32% upward, and earnings were $2.46 per share. 2008 guidance is for operating profit growth of 25%. Trading at 25 times forward analyst earnings guidance and 26 times its just-released trailing earnings, Novo won't show up on any value investor's stock screens, but it's hard to complain because Novo is operating in a recession-proof sector.

What makes Novo Nordisk exciting is its long-term Rule Breakers-type of growth potential. More and more people around the world will be using Novo's products in the years to come. For those investors wanting to own shares of an international drugmaker at the epicenter in fighting a huge health crisis, Novo Nordisk fits the bill.

Will Novo Nordisk outperform in the long run or is it overpriced? Come see what other investors think and rate the stock yourself in The Motley Fool's CAPS database.

Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has an A+ disclosure policy.