Angina - ranolazine
Angina sufferers experience repeated attacks of cardiac pain, usually when exercising, because plaque build-up within the coronary arteries does not allow sufficient oxygen to reach the heart.
Angina sufferers experience repeated attacks of cardiac pain, usually when exercising, because plaque build-up within the coronary arteries does not allow sufficient oxygen to reach the heart.
It is normally treated with beta blockers or glyceryl trinitrate, and in severe cases angioplasty or coronary artery bypass surgery will be necessary.
CV Therapeutics has been developing an alternative drug therapy. Ranolazine is a partial fatty acid oxidation (pFOX) inhibitor, designed to improve the efficiency of the way the heart uses the oxygen it has available. The heart gets its energy either from glucose or fatty acids; using glucose produces more energy per unit of oxygen than fatty acids. pFOX inhibitors shift the metabolism towards glucose use and may be of benefit in treating angina.
Various trials have been carried out. In one, 158 patients discontinued their beta blocker therapy and were randomised into a double-blind three period crossover study in which they were given 400mg ranolazine three times a day, 100mg atenolol a day or placebo.1 Both drugs gave improvement in exercise tests, and those given ranolazine had significantly longer exercise duration. Unlike atenolol, it did not decrease blood pressure or heart rate.
A larger study was carried out in 823 patients with stable angina who were already receiving amlodipine, atenolol or diltiazem treatment.2 They were given placebo or 750 or 1,000mg of sustained release ranolazine twice a day in addition to their existing drugs for 12 weeks. Both doses of the new drug increased treadmill exercise duration by a greater amount than placebo and increased the time to angina. They also reduced the frequency of attacks and nitro-glycerine uses.