Biotech CV Therapeutics announced their chronic angina drug Ranexa had won U.S. health authorities approval as a first-line treatment for the condition. Ranexa (ranolazine) was previously approved for patients with chronic angina but had no success with other treatments.

Ranexa's new labeling says the drug is shown to reduce abnormal heart rhythms, including arrhythmias in the lower chambers of the heart, new onset atrial fibrillation and dangerously slow heartbeats in patients with heart disease. Additionally, the new label says the drug reduces the average blood sugar in patients with diabetes; and Ranexa can now also be used in combination with traditional therapies.

CV Therapeutics said it earned $ 30.3 million dollars in net product sales from Ranexa in the third quarter, up 19 percent sequentially from the second quarter, helping it to narrow its quarterly loss.

Ranexa is cleared in Europe as an add-on therapy for patients with symptomatic chest pain who have tried other anti-angina therapies unsuccessfully. Norvasc (Pfizer) and Tiazac (Forest Labs) are its competitors.

According to the company, chronic angina, or debilitating chest pain, affects more than 9 million people in the U.S.