Trimetazidine in Angina Combination Therapy--the TACT study: trimetazidine versus conventional treatment in patients with stable angina pectoris in a randomized, placebo-controlled, multicenter study

Abstract

The aim of this study was to assess the efficacy and acceptability of trimetazidine (TMZ) in combination with hemodynamic agents (beta-blockers or long-acting nitrates) in 177 stable angina patients. In this randomized, placebo-controlled study (TACT: Trimetazidine in Angina Combination Therapy), stable angina patients resistant to nitrates or beta-blockers were selected. After a 1-week selection period (W0), patients who had a difference of <10% in duration between 2 positive exercise tests, defined as 1-mm ST-segment depression (STD) 80 milliseconds after J point with angina pain or 1.5 mm without pain were randomly treated with TMZ (20 mg t.i.d., n = 90) or placebo (Pbo t.i.d., n = 87) orally. A final exercise test was performed after 12 weeks of treatment (W12). The efficacy was assessed by exercise test duration, time to 1-mm STD, time to angina onset, mean number of angina attacks, mean short-acting nitrate consumption, and rate-pressure product. Differences (W12 - W0) in these parameters were analyzed using the Student t test. All statistical tests were conducted at the 5% significance level. At inclusion and during the study, 52% of patients received long-acting nitrates, and 48% were treated with a beta-blocker as monotherapy. At the beginning of the study, the TMZ and Pbo groups were statistically homogeneous with respect to all analyzed characteristics (demographic characteristics, characteristics of anamnesis, characteristics used for evaluation of antianginal therapy efficacy). For various reasons, 11 patients (7 from the Pbo group and 4 from the TMZ group) were excluded from the trial. A total of 166 patients (80 from the Pbo group and 86 from the TMZ group) completed the study in full compliance with the protocol. After 12 weeks of therapy, exercise test duration increased from 417.7 +/- 14.2 (W0) to 506.8 +/- 17.7 seconds (W12) in the TMZ group versus 435.3 +/- 14.8 (W0) to 458.9 +/- 16.2 seconds (W12) in the Pbo group (P < 0.05). Time to 1-mm STD increased from 389.0 +/- 15.3 (W0) to 479.6 +/- 18.6 seconds (W12) in the TMZ group versus 411.8 +/- 15.2 (W0) to 428.5 +/- 17.3 seconds (W12) in the Pbo group (P < 0.05). Time to onset of anginal pain increased from 417.0 +/- 16.9 (W0) to 517.3 +/- 21.0 seconds (W12) in the TMZ group versus 415.1 +/- 16.5 (W0) to 436.4 +/- 18.5 seconds (W12) in the Pbo group (P < 0.005). The mean number of anginal attacks per week decreased from 5.6 +/- 0.6 to 2.7 +/- 0.5 in the TMZ group versus 6.8 +/- 0.7 to 5.1 +/- 0.7 in the Pbo group (P < 0.05), mean consumption short-acting nitrates per week decreased from 5.2 +/- 0.9 to 2.8 +/- 0.8 in the TMZ group versus 5.5 +/- 0.8 to 4.1 +/- 0.9 in the Pbo group (NS). No change in the rate-pressure product was seen in both. The combination of trimetazidine with beta-blockers or long-acting nitrates significantly improves exercise stress test parameters and angina symptoms compared with placebo. Due to its metabolic effect, free of any hemodynamic action, trimetazidine has proven to be beneficial for combination in patients with stable angina.