Effectiveness and Tolerability of Ivabradine with or Without Concomitant Beta-Blocker Therapy in Patients with Chronic Stable Angina in Routine Clinical Practice

INTRODUCTION: In the prospective, open-label, non-interventional, multicenter RESPONSI(f)VE study, the effectiveness, response rates and tolerability of ivabradine with or without beta blocker (BB) were evaluated in patients with chronic stable angina pectoris (AP) in daily clinical practice. METHODS: In patients with AP, ivabradine was given twice daily in flexible doses for 4 months. Resting heart rate (HR), number of angina attacks, short-acting nitrate use, severity of symptoms [by Canadian Cardiovascular Society (CCS) score] and tolerability with or without existing BB therapy were documented and analyzed using descriptive statistical methods. RESULTS: In total, 1250 patients with AP (mean age 66.0 ± 10.9 years, 59.6% male, 31.9% previous myocardial infarction) and an indication for ivabradine were included. Sixty-five percent of all patients received BB. Further concomitant standard medication included aspirin (74.2%), statins (69.3%), angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (84.2%), diuretics (40.0%), long-acting nitrates (15.7%), and calcium antagonists (21.4%). After 4 months of ivabradine treatment (mean daily dose 11.0 ± 2.7 mg), mean HR was reduced from 82.4 ± 11.8 beats per minute (bpm) to 67.1 ± 8.4 bpm. The average number of angina attacks/week decreased from 1.2 ± 1.9 to 0.1 ± 0.6 and the average use of short-acting nitrates/week from 1.5 ± 2.8 units to 0.2 ± 1.0 units. CCS classification of patients improved from 76% classified in CCS grades II or III and 24% in CCS grade I to 66% classified in CCS grade I and only 35% remaining in CCS grades II or III at study end. Response rate to ivabradine (defined as HR <70 bpm or HR reduction ≥10 bpm) reached 87%. HR reduction, symptomatic improvement and response rates were comparable in patients with or without BB. Adverse drug reactions were reported for 2.2% of patients. CONCLUSION: In this prospective study over a four-month period in clinical practice, ivabradine effectively reduced HR, angina attacks, and nitrate consumption in patients with AP with or without concomitant BB therapy. Ivabradine improved CCS scores and achieved a high treatment response rate with good general tolerability. FUNDING: Servier. TRIAL REGISTRATION: Controlled-trials.com identifier, ISRCTN73861224.