Influence of SIN-1 on Platelet Ca2+ Handling in Patients with Suspected Coronary Artery Disease: Ex Vivo and In Vitro Studies

Pharmacotherapy in patients with vasomotor disorders

Background

Anginal symptoms in patients with non-obstructive coronary artery disease are frequently related to vasomotor disorders of the coronary circulation. Although frequently overlooked, a distinct diagnosis of different vasomotor disorders can be made by intracoronary function testing. Early detection and treatment seems beneficial, but little evidence is available for the medical treatment of these disorders. Nevertheless, there are several pharmacotherapeutic options available to treat these patients and improve quality of life.

Methods & findings

We performed an extensive yet non-systematic literature search to explore available pharmacotherapeutic strategies for addressing vasomotor disorders in individuals experiencing angina and non-obstructive coronary artery disease. This article presents a comprehensive overview of therapeutic possibilities for patients exhibiting abnormal vasoconstriction (such as spasm) and abnormal vasodilation (like coronary microvascular dysfunction).

Conclusion

Treatment of vasomotor disorders can be very challenging, but a general treatment algorithm based on the existing evidence and the best available current practice is feasible.

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.

Efficacy and safety of molsidomine once-a-day in patients with stable angina pectoris

BACKGROUND

The objective of this study was to compare the efficacy and tolerability of molsidomine prolonged-release 16 mg once-a-day (o.a.d.) with 8 mg twice-a-day (b.i.d.) and placebo in patients with stable angina pectoris.

METHODS

After a run-in placebo period of 7 days, the two formulations were compared acutely and then chronically (2 weeks) using cycloergometric tests and a randomized, multicenter, double-blind, double-dummy, crossover design in 533 patients. The quality of life was assessed using the frequency of anginal crises and nitrate sublingual tablets consumption.

RESULTS

Both formulations significantly improved exercise test parameters compared with placebo, being it after acute drug intake or after a 2-week treatment period and independently of spontaneous diurnal variation in exercise tolerance. Noninferiority of molsidomine 16 mg compared with 8 mg was demonstrated with a statistically significant superiority of the 16-mg formulation from 14 to 24 h postintake. Both treatments reduced incidence of anginal attacks and use of sublingual isosorbide dinitrate tablets. Tolerability of active drugs was satisfactory, the incidence of drug-related headache being not significantly different from placebo. Only hypotension was significantly more frequent with molsidomine 16 mg than with placebo, pretrial diastolic blood pressure being significantly lower in these patients than in those who did not develop hypotension during the study.

CONCLUSIONS

Both molsidomine formulations were effective in controlling patients' angina, did not induce any habituation and were well tolerated. However, the once-daily 16-mg formulation tended to provide better 24-h protection against myocardial ischemia than the 8-mg b.i.d. formulation.