Exercise tolerance in coronary patients: randomized trial of two-week treatment with molsidomine versus placebo

Tolerability to 1-year treatment with once-daily molsidomine in patients with stable angina

Prolonged-release molsidomine 16 mg once daily) QD (has proved effective in the short-term treatment of patients with stable angina. The purpose of this multicenter study was to assess its long-term tolerability and clinical effectiveness. A total of 320 patients with stable angina were treated for 1 year with molsidomine 16 mg QD administered open label as monotherapy or add-on therapy, when beta blockers and/or calcium antagonists were prescribed concomitantly) in 128 patients, ie, 40% of cases), depending on the severity of disease and/or local therapeutic policies. In all, 293 patients (91.6%) completed the study. The proportion of patients who reported drug-related adverse events (AEs) was 9.1%, which is not significantly different (P=.13) from the 5.9% observed during previous short-term (2-4 wk) treatment. Headache accounted for 80.6% of all drug-related AEs and required discontinuation of the drug in one quarter of patients who reported the symptom (ie, 1.9% of the 320 patients involved in the study). No serious drug-related AEs occurred during the study. Tolerability to molsidomine, evaluated with use of a visual analog scale (VAS), improved by 20% from beginning to end of 1-year follow-up. Two-by-two Bonferroni's comparisons were significant at the .05 level between the 2-month assessment and assessments performed at 8, 10, and 12 months. No age-time interaction was noted (P=.82). Heart rate, blood pressure, electrocardiogram, and blood parameters showed no statistically significant or clinically relevant changes during the study. Compliance with treatment was satisfactory throughout the follow-up period. There was no significant change in the weekly frequency of anginal attacks and consumption of short-acting nitroderivatives during the 1-year study (P=.07 and P=.12,respectively), but their frequency was significantly (ie, approximately 50%) lower than during a preceding short-term treatment period (P<.0001 and P=.014, respectively). Subjective clinical status, evaluated through an appropriate VAS, improved by 38% from start to end of 1-year follow-up. Bonferroni's comparisons between baseline and subsequent 2-month evaluations were all significant at the .05 level. No age-time interaction could be seen for frequency of anginal attacks and consumption of short-acting nitroderivatives, nor for clinical status )P=.10, P=.11, and P=.51, respectively). Neither tolerability to molsidomine nor effectiveness of the drug was biased by concomitant antianginal therapies, insofar as none of these parameters showed a significant treatment type (ie, molsidomine administered as monotherapy or add-on therapy)-time interaction (VAS for tolerability: P=.44; angina: P=.39; nitroderivatives: P=.72; VAS for clinical status: P=.62). Molsidomine 16 mg QD administered for 1 y to patients with stable angina was well tolerated and remained effective during the entire treatment period, independent of age and concomitant antianginal therapy.

Efficacy and safety of once- and twice-daily formulations of molsidomine in patients with stable angina pectoris: double-blind and open-label studies

Molsidomine, a sydnonimine acting as a heterocyclic direct nitric oxide donor, has been used for many years in several European countries for the treatment of patients with stable angina pectoris. The efficacy and tolerability of a novel once-daily 16-mg formulation of molsidomine (M16) were compared with those of the currently used twice-daily 8-mg molsidomine tablet (M8) in 666 patients. Study 1, a multicenter, randomized, double-blind, placebo-controlled, twin crossover study, involved 533 patients given acute and 2-week treatment with each drug formulation. Study 2, a multicenter, open-label, sequential, add-on trial, compared M16 and M8 in 133 patients. Drug effects on exercise capacity (study 1 only), frequency of anginal attacks and consumption of short-acting itroderivatives, and incidence of adverse events (AEs) were evaluated. Compared with placebo, M16 increased exercise capacity by 15% (P<.001) at the start of study 1 and by 13% (P<.001) after 2 weeks' treatment, and was not inferior to M8. In terms of anginal attack frequency and nitroderivative consumption, M16 was not inferior to M8 in either study. Moreover, compared with M8, M16 produced a statistically and clinically significant reduction in the incidence of anginal attacks in elderly (>/=75 y) but not in younger patients (<75 y) (study 2), nor in patients from study 1. No significant difference from M8 was found in either study in short-acting nitroderivative consumption. No tolerance to M8 or M16 was observed after 2-week treatment. No statistically significant differences in incidences of all AEs and drug-related AEs were observed between M16 and M8 in either study. The same held true for proportions of patients experiencing AEs and drug-related AEs on M16 vs M8: in study 1-14.3% and 11.8% for all AEs (P=.218), 6.9% and 5.4% for drug-related AEs (P=.280); in study 2-1.3% and 1.3% for all AEs, 0% and 1.3% for drug-related AEs (P>.10) in young patients; and in the elderly, 3.6% and 0% for drug-related AEs (P>.10). Only the proportion of elderly patients with all AEs was significantly higher with M16 than with M8: 14.5% vs 1.8% (P=.039). M16 once daily was effective and well tolerated in investigated patients with stable angina pectoris, particularly the elderly, affording 24 hours of therapeutic activity. M16 was not inferior to M8 given twice daily in terms of efficacy, safety profile, and tolerability.

A pilot double-blind randomized placebo-controlled study of molsidomine 16 mg once-a-day in patients suffering from stable angina pectoris: correlation between efficacy and over time plasma concentrations

OBJECTIVES

A new once-a-day (o.a.d.) formulation of molsidomine (16 mg) was evaluated in patients with stable angina pectoris. The aims were to characterize its pharmacokinetics after a single dose, to demonstrate its clinical efficacy and safety versus placebo and to investigate correlations between pharmacokinetics and pharmacodynamics.

METHODS

Forty-two patients were recruited in a double-blind, crossover, randomized placebo-controlled trial. The pharmacokinetics of molsidomine and SIN-1, its active metabolite, were determined at specific time points (3, 6, 10, 14, 18, 22 and 24 h) after the administration of a single dose of molsidomine 16 mg o.a.d. in all patients distributed into seven groups. Twenty-eight of these 42 patients showed a positive baseline cycloergometric exercise test response during the run-in placebo period and were used to compare the efficacy of molsidomine to placebo. Relationships between plasma concentration in molsidomine or SIN-1 and ischemic threshold were assessed in 16 of the 28 patients with a positive exercise test at baseline. Indeed, the censored variable ischemia-limited tolerance to exercise could not be evaluated in those patients who did not show exercise-induced ischemia anymore under molsidomine 16 mg o.a.d. Pharmacokinetic-pharmacodynamic relationships were evaluated using regression models and correlation coefficients.

RESULTS

The highest average concentration in molsidomine and SIN-1 occurred after 6 h, then a plateau of 15-20 ng/ml molsidomine and 0.8-3.0 ng/ml SIN-1 was maintained for at least 8 h and the mean residual molsidomine concentration 24 h post-drug intake was around 8 ng/ml, still in the effective range of 5-10 ng/ml. A significant increase in total workload (+52 W min, P=0.009), total exercise time (+32 s, P=0.003) and time to angina (+25 s, P=0.016) was measured with molsidomine 16 mg o.a.d. relative to placebo. Using linear regression, significant correlation coefficients were determined between molsidomine plasma concentrations (but not SIN-1) and exercise test improvements (r=0.827, P<0.001 for the total workload; r=0.772, P<0.001 for the total exercise time; and r=0.566, P=0.028 for the time to 1 mm ST-segment depression).

CONCLUSION

The pharmacokinetics of molsidomine 16 mg in patients with stable angina pectoris is compatible with a o.a.d. dosage regimen. This o.a.d. formulation is effective and well-tolerated, providing a 24-h therapeutic control of myocardial ischemia. A positive and significant linear relationship between molsidomine plasma concentration and the increase in exercise tolerance was observed.

Additional molsidomine in refractory unstable angina pectoris

In a prospective single-blind study we examined the effects of additional molsidomine in 20 patients (63 +/- 10 years; 15 males, 5 females) with unstable resting angina (greater than or equal to 3 attacks/24 hours) refractory to triple therapy (nitrates, calcium antagonists, and beta blockers) combined with heparin or aspirin. All but one patient had coronary artery disease documented by coronarography (n = 17) or by recent myocardial infarction (n = 3). Two patients had angiographically documented severe coronary spasms. Patients entered the study if coronary bypass surgery or PTCA could not be performed within 3 days after angiography (n = 9) or was not feasible due to anatomical or technical reasons (n = 6), concomitant malignant disease (n = 2), or age greater than 75 years (n = 3). All patients received molsidomine orally 12 to 24 mg/day. In 15 of the 20 patients molsidomine was given i.v. initially, starting with 20 mg i.v., followed by infusion of 1 to 4 mg/hour. Heart rate and blood pressure did not change significantly, and eight patients had a slight decrease of systolic and diastolic blood pressure. Severe adverse effects did not occur, and moderate headaches were reported by five patients. In 13 patients, unstable angina could be stabilized, and they remained free of resting angina; five had a marked reduction of the frequency of anginal attacks. In two patients, molsidomine was without demonstrable beneficial effects.(ABSTRACT TRUNCATED AT 250 WORDS)

[Molsidomine in the treatment of coronary insufficiency]

Molsidomine, a predominantly venous vasodilator, has been coronary disease. The basic mechanism of its anti-anginal effect is a reduction in myocardial oxygen consumption due to a fall in left ventricular end-diastolic pressure resulting from the vasodilator action of the drug. To this may be added direct dilatation of the main coronary vessels on the surface of the heart, which may account for part in its therapeutic effects in unstable and vasospastic angina. The effectiveness of molsidomine has been evaluated by controlled drug versus placebo or drug versus reference anti-anginal drug studies in 3 types of angina pectoris: exertion, unstable and vasospastic. The usefulness of the drug has also been established in acute and chronic left ventricular failure of ischaemic origin. Because of its high bioavailability when administered orally, molsidomine shows little inter-individual variations in its pharmacodynamic effects. Unlike nitrates, it can be administered for long period without gradual loss of activity with time. Finally, on several experimental models molsidomine has been shown to exert an antiplatelet effect, but the therapeutic implications of this finding have yet to be evaluated.