QUINAPRIL HYDROCHLORIDE EFFECTS ON RENAL-FUNCTION IN PATIENTS WITH RENAL DYSFUNCTION AND HYPERTENSION - A DRUG-WITHDRAWAL STUDY

Patients with mild to moderate hypertension (diastolic blood pressure greater than or equal to 95 and less than or equal to 115 mmHg) and re nal dysfunction entered one of two studies to assess the safety of eff icacious daily doses of quinapril on renal function and blood pressure . Twenty-four patients with moderate renal impairment (MRI) (creatinin e clearance >30 and less than or equal to 60 ml/min) entered 24 weeks of open-label quinapril treatment; 31 patients with chronic renal fail ure (CRF) (creatinine clearance <30 ml/min) entered 16 weeks of open-l abel quinapril treatment. Patients with MRI initially received quinapr il 5 mg once daily (qd) followed by titration to a maximum dosage of 4 0 mg/day (furosemide optional at 40 mg only). Patients with CRF initia lly received quinapril 2.5 mg qd and were titrated up to 20 mg/day (fu rosemide optional). Open-label quinapril treatment resulted in signifi cant decreases in mean systolic (SBP) and diastolic (DBP) blood pressu re. The 20 patients with MRI and the 28 with CRF who completed the ope n-label phase were then randomly assigned to continue active drug or t o receive placebo in a 4-week, double-blind, drug-withdrawal phase. Du ring the double-blind withdrawal phase, placebo-treated patients had s ignificant increases in mean SBP and DBP from the end of open label. C reatinine clearance was essentially unchanged following open-label qui napril treatment or quinapril withdrawal. In conclusion, in patients w ith mild to moderate hypertension and renal dysfunction, quinapril in dosages of 5-40 mg qd for patients with MRI and 2.5 to 20 mg qd for pa tients with CRF significantly reduces blood pressure without adversely affecting renal function.