On Monday, Rule Breakers pick CV Therapeutics (NASDAQ:CVTX) took another step to widen the use of its only marketed drug, Ranexa, with the Food and Drug Administration accepting multiple marketing applications for the drug.

Ranexa is CV Therapeutics' lead drug. In January, the FDA approved it to help reduce angina in those who suffer from attacks of the excruciating chest pains.

The problem with Ranexa is that it's only approved for angina sufferers not adequately treated by their current medications, like beta blockers. Ranexa has this second-line label because of a perceived elevated risk of a heart condition that can result in sudden death when it is used.

CV Therapeutics posted $18.4 million in Ranexa sales for the third quarter, up 20% versus the previous quarter. With the current Ranexa label likely impeding effective marketing of the drug, CV Therapeutics ran a large phase 3 study named Merlin to try to convince the FDA to allow a broader label for the drug as a front-line treatment for angina.

The supplemental New Drug Application that the FDA accepted Monday is CV Therapeutics' attempt to get this improved front-line angina label after the Merlin study was completed earlier this year.

In a secondary endpoint of the study, CV Therapeutics also measured Ranexa's effects on improving diabetics' blood glucose levels. Controlling blood glucose levels with insulin shots like Sanofi-Aventis' (NYSE:SNY) Lantus or other anti-diabetic compounds like Eli Lilly (NYSE:LLY) and Amylin Pharmaceuticals' (NASDAQ:AMLN) Byetta is an important part of any type 2 diabetics' daily routine.

Based on strong Merlin diabetes data, CV Therapeutics filed to try to get Ranexa approved as a treatment for diabetics with coronary artery disease. This is a very large patient population.

Besides its effectiveness, what makes Ranexa stand out compared with competitors like GlaxoSmithKline's (NYSE:GSK) Avandia is that it might not have the potential heart safety issues that Avandia does. Considering that most diabetics die of coronary heart disease, that could be a potent marketing advantage.

The PDUFA date for both the Ranexa front-line angina label expansion and new diabetes indication is July 28 of next year. Because the applications are under review by different FDA divisions, it's likely that approval or denial will come at different times despite the same PDUFA action date.

It's worth noting that the FDA's decision on each application has no bearing on the other's odds of approval. The diabetes indication might be a stretch without further clinical testing, but now CV Therapeutics has two shots to help jump-start Ranexa sales next year.

CV Therapeutics is a pick of our Rule Breakers newsletter. You can check out all our other recommendations with a 30-day free trial. GlaxoSmithKline and Eli Lilly are Income Investor picks.

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