Ivabradine is a specific heart rate-lowering antianginal agent that was evaluated in a clinical development program involving approximately 3,000 patients with stable coronary artery disease, most with angina pectoris. We analyzed the pharmacokinetics, efficacy (evaluated by exercise tolerance testing), safety, and effects on glucose metabolism of ivabradine in patients with diabetes mellitus (DM) in this program. Most analyses included data from 535 patients with DM, approximately 18% of the overall patient sample. Patients with DM were older, more likely to be women, and more likely to have more severe angina pectoris than patients without DM. The pharmacokinetics of ivabradine did not differ in patients with DM versus those without DM. A reduction in the heart rate at rest with ivabradine was similar in those with (15.2%) and without (15.7%) DM. At baseline, the exercise capacity tended to be lower in the patients with DM, but the improvements in most exercise tolerance measures with ivabradine treatment were similar in patients with and without DM. No special safety concerns were associated with ivabradine in those with DM. The rates of sinus bradycardia and visual disturbances, known to be related to the action of ivabradine, showed no relative increase in the patients with DM. Ivabradine treatment was not associated with adverse effects on glucose metabolism. In conclusion, ivabradine was effective in preventing angina in patients with DM and was not associated with particular safety concerns or adverse effects on glucose metabolism. Ivabradine represents an attractive alternative to beta blockers in patients with stable angina pectoris and DM.