Cardioprotective agent - MC-1

Patients undergoing cardiac bypass surgery and angioplasty - not to mention those who experience acute coronary syndrome events - are at risk of the heart becoming further damaged by ischaemia or ischaemia reperfusion injury.

There are as yet no drugs available that provide a direct cardioprotective effect in such cases, and Canadian company Medicure is developing MC-1 as a potential first-in-class drug that could improve patient survival and quality of life.¹

MC-1 is a naturally occurring metabolite of vitamin B6. In a trial to evaluate its effectiveness as a cardioprotective agent in patients undergoing elective percutaneous coronary intervention, 60 patients were randomised to placebo or 10mg/kg MC-1 at least four hours before treatment, and then a further 5 mg/kg given twice a day for 14 days.² Those given the drug had significantly lower levels of CK-MB, indicating lower infarct sizes.

A Phase II trial has also been carried out in 901 high risk coronary artery disease patients who were undergoing coronary artery bypass graft surgery, who were given 250mg or 750mg of the drug a day or placebo. Those given the lower dose had a 37% reduction in the combined incidence of death, non-fatal myocardial infarction and non-fatal stroke compared with placebo, and the lower dose was found to be more effective than the higher dose.

It is also being investigated in conjunction with the angiotensin converting enzyme inhibitor lisinopril in hypertensive diabetics.³ A randomised double-blind placebo controlled crossover study was carried out in 160 patients with Type II diabetes and hypertension; they were given MC-1 and lisinopril or placebo for eight weeks, and then placebo or MC1-alone for a further eight weeks, or eight weeks of the combination treatment followed by eight weeks of placebo or lisinopril alone. It was found that the combination was more effective than either drug on its own in reducing blood pressure. There were few adverse events related to the treatment.