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Trial findings mark 'significant advance' in angina treatment Vienna, September, 2003 Results from the INITIATIVE study1, the largest phase III trial ever carried out for the treatment of stable angina, herald what has been described as a 'significant advance' in the management of the condition, which afflicts 4% of adults in the UK and costs the NHS some ?700 million per year2. Findings from the 4-month, multi-centre study, presented for the first time at the European Society of Cardiology (ESC) Congress in Vienna, show that ivabradine (Procoralan® , Servier), a new chemical entity, was at least as effective as the beta blocker atenolol but did not display any of the side-effects commonly associated with beta-blockers, such as sexual dysfunction, asthenia or bronchospasm. Ivabradine is the first selective and specific If inhibitor, a new class of compound, which exclusively reduces heart rate by specific action on the sino-atrial node. Unlike some other treatments which also reduce heart rate, ivabradine does not influence myocardial contractility or blood pressure, and it preserves atrioventricular conduction and vascular repolarisation.3 This is a significant factor, since according to a recent survey of cardiologists4 carried out for the newly formed Angina Forum, beta blockers are contraindicated or not tolerated in around one in five angina patients. Others suffer side-effects but continue on the medication. Results presented earlier this year had already shown that ivabradine had significant anti-anginal and anti-ischaemic efficacy compared to placebo3; the aim of INITIATIVE was to demonstrate its 'non-inferiority' to a beta blocker in a larger trial. INITIATIVE, a multi-centre trial involving nine countries, was a 4-month randomized, double blind comparative (ivabradine versus atenolol) study of 939 patients with a 3-month history of stable angina and documented coronary artery disease1. Ivabradine significantly increased total exercise duration and was shown to be at least as effective as atenolol after both 1 month and 4 months of treatment in all treatment groups. All exercise test criteria were similarly improved, including time to limiting angina, time to angina onset and time to 1-mm ST-segment depression (an electrocardiographic indication of ischaemia). Ivabradine, which is expected to be available on the UK market within the next two years, is currently in Phase III trials as part of the largest clinical programme ever carried out to evaluate anti-ischaemic efficacy with exercise tests. The ongoing clinical development programme conducted by Servier involves more than 4,000 patients. Notes The Angina Forum is a newly formed multidisciplinary group of medical professionals with an interest in the management of angina. The major aim of the group is to explore and highlight issues in angina management and advise on medical and surgical developments. References 1. Anti-anginal and anti-ischaemic effects of the If current inhibitor ivabradine versus atenolol in stable angina. Tardif JC for the INITIATIVE study investigators. A four-month, randomized, double blind, multi-centre trial. Oral Communication August 31, 2003. European Society of Cardiology Congress, Vienna, Austria. 2. Health Survey for England - Cardiovascular Disease 1999 3. Borer J S et al for the Ivabradine Investigators Group. Anti-anginal and anti-ischaemic effects of ivabradine, an If inhibitor, in stable angina. Circulation. 2003;107:817-823. 4. Cardiologists' attitudes to angina management. Survey of 75 cardiologists conducted by NOP Healthcare, August 2003. See also: ANGINA ADVANCE (8/9/03) |