Ranexa (ranolazine) is the first drug to be marketed in the United States from a new class of drugs, called the fatty acid oxidation inhibitors, that are being developed for the treatment of angina.
This new drug causes the heart muscle to switch from using fatty acids to using glucose for energy production. This is a useful "switch" in patients with angina because using glucose requires less oxygen. Reducing the amount of oxygen used by the heart allows the heart to function longer without developing ischemia, even when blood flow through the coronary arteries is partially blocked by atherosclerosis.
In addition to switching the heart muscle to glucose metabolism, Ranexa also prevents excess calcium from entering heart muscle cells during periods of ischemia, which tends to reduce cardiac damage.
Ranexa has been shown to significantly improve the amount of time patients with stable angina are able to exercise before developing symptoms.
Originally, the chief concern about Ranexa was that it can prolong the "QT interval" on the ECG (a measurement of electrical activity within the heart) - and some drugs that do that can increase the risk of developing dangerous heart arrhythmias. However, careful studies have shown this risk to be minimal or nonexistent with Ranexa. In fact, Ranexa now has been shown to actually reduce the risk of developing ventricular arrhythmias and atrial fibrillation.
The most common side effects of Ranexa have been headache, constipation and nausea.
Ranexa was originally recommended as a second or third choice drug in treating patients with angina, but in November, 2008 it was approved by the FDA as a first-line agent.
Read here for more on the noninvasive treatment of angina.
Sources:
Chaitman, BR. Ranolazine for the treatment of chronic angina and potential use in other cardiovascular conditions. Circulation 2006; 113:2462.
Morrow DA, Scirica BM, Karwatowska-Prokopczuk E, et al. Effects of ranolazine on recurrent cardiovascular events in patients with non-ST-elevation acute coronary syndromes. The MERLIN-TIMI 36 randomized trial. JAMA 2007; 297:1775-1783.
Newby LK and Peterson ED. Does ranolazine have a place in the treatment of acute coronary syndromes? JAMA 2007; 297:1823-25.
