On Monday, Rule Breakers pick CV Therapeutics (NASDAQ:CVTX) announced that it had filed a new drug application for its second potential marketed compound, the cardiac stress agent regadenoson.

Regadenoson is a treatment used to get patients' hearts beating faster in order to check for coronary artery disease. In 2005 alone, there were over four million tests done in the U.S. using stress agents similar to regadenoson, to check for coronary artery disease. This puts the market potential for the drug in the hundreds of millions of dollars, depending on the type of label it can achieve at the FDA.

The odds of regadenoson gaining regulatory approval are very high, considering that it successfully met its primary endpoint in two phase 3 studies. If the FDA grants regadenoson a regular ten month review date, this puts possible approval of the compound in the second quarter of next year, which means that U.S. marketing partner Astellas will be able to ramp up sales by the end of 2008.

No matter how the FDA rules on regadenoson next year, CVT's future is looking brighter; the rate of prescription growth for angina treatment Ranexa recently increased after the release of a positive phase 3 safety study for the drug. If CVT can do a better job of handling its expenses and Ranexa stays on this improved sales growth trajectory, investors who buy shares at this level will be pain-free in just a few years.

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