Patients with cardiovascular disease who achieve target low-density lipoprotein (LDL) levels with statin therapy still have some cardiovascular risk. A clinical evaluated whether a combination treatment of simvastatin with extended-release niacin, by increasing high-density lipoprotein (HDL) was superior in reducing cardiovascular risk compared to simvastatin alone.

Subjects being treated with simvastatin were randomly assigned to receive extended-release niacin (1500 - 2000 mg/day, n= 1718) or placebo (n=1696). The primary endpoint was death due to coronary heart disease, myocardial infarction, ischemic stroke, hospitalization for an acute coronary syndrome, or symptom-drive coronary or cerebral revascularization.

The trial was terminated after three years due to lack of efficacy. Niacin co-administration significantly increased median HDL cholesterol from 35 mg/dL to 42 mg/dL) and lowered LDL cholesterol from 74 mg/dL to 62 mg/dL). The primary endpoint occurred in 286 patients in the niacin group and in 253 patients in the placebo group (p = 0.79).

Calculate the hazard ratio of the primary endpoint for the niacin group compared to placebo.