The Food and Drug Administration (FDA) announced the approval of Ranexa (ranolazine), a new drug for the treatment of chronic angina. Ranexa, a new molecular entity (NME), is the first drug approved to treat chronic angina in over ten years. Although several pharmacological activities of ranolazine have been described, the precise way the drug works is not fully understood. Because Ranexa affects electrical conduction in the heart (prolong the QT interval), it should only be used by patients who have not responded to other anti-anginal (long-acting nitrates, calcium channel blockers and beta blockers) drugs.
Chronic angina is characterized by episodes of chest pain, pressure, or discomfort that occur during exercise because the heart muscle is not getting enough oxygen. The most common cause of angina is coronary heart disease, in which the coronary arteries that supply the heart with oxygen – rich blood become blocked with plaque deposits. According to the American Heart Association, approximately 6.8 million Americans are diagnosed with angina every year. While many of these patients respond to other treatments, including surgery and other approved drugs, some remain with angina despite receiving these treatments. Acute attacks of angina are treated with nitroglycerin placed under the tongue whereas treatments for chronic angina are given to increase the amount of exercise a person can do before angina occurs. This is usually tested by showing that people with angina can exercise longer on a treadmill or bicycle when they take the drug.
“Chronic angina limits people’s activities,” said Dr. Steven Galson, MD, Director of FDA’s Center for Drug Evaluation and Research. “The approval of Ranexa provides a new treatment option for Americans who continue to suffer symptoms of angina despite using other angina drugs.”
Ranexa was studied in patients with chronic angina who still had symptoms despite being treated with other anti-anginal drugs. Two clinical trials, ERICA (Efficacy of Ranolazine in Chronic Angina) and CARISA (Combination Assessment of Ranolazine In Stable Angina) were conducted. In ERICA, 565 patients who were experiencing about 4.5 angina attacks per week while taking a full dose of a calcium channel blocker were randomized to Ranexa or placebo for 6 weeks. Patients receiving Ranexa had a reduction in angina attacks of about 1 attack per week, compared with those in the placebo group.
In CARISA, 823 patients on either a calcium channel blocker or beta blocker (atenolol) were randomized to Ranexa or placebo and followed for 12 weeks using a formal exercise treadmill test. Patients in the Ranexa group had a mean exercise improvement similar to that seen with other anti-anginal therapies.
In both studies, Ranexa appeared to be less effective in women than in men.
In clinical studies, common side effects included dizziness, headache, constipation and nausea.
Ranexa is manufactured by CV Therapeutics, Inc. in Palo Alto, California.