A 6-MONTH STUDY OF THE EFFICACY AND SAFET Y OF DILTIAZEM-LP 300 MG IN1172 HYPERTENSIVE PATIENTS

This six-month, multicenter, open trial in 1172 patients with mild-to- moderate hypertension (supine diastolic blood pressure in the 95-114 m mHg range) was conducted to evaluate the efficacy and the clinical, la boratory, and electrocardiographic safety of diltiazem LP 300 mg. Afte r a washout period, diltiazem LP 300 mg (1 capsule per day) was given as single-drug therapy for six weeks. At the follow-up visits at six w eeks and four months, patients whose blood pressure was adequately con trolled were instructed to continue the same treatment, whereas those who remained hypertensive were given an additional antihypertensive ag ent. After six weeks of diltiazem LP 300 mg alone, a response (supine diastolic blood pressure less-than-or-equal-to 90 mmHg) was seen in 67 .4 % of patients. A total of 884 patients (75.49 %) continued diltiaze m LP 300 mg as monotherapy for the duration of the trial ; in the 288 (24.6 %) remaining patients, addition of a second antihypertensive age nt increased the response rate to 88.6 % after four months and 91.4 % after six months. Premature withdrawal occurred in 9.47 % of patients. Two-thirds of all adverse events and reasons for premature withdrawal were ascribable to the vasodilating effects of diltiazem. Mean heart rate decreased slightly (69.4 +/- 10.1 bpm at six months versus 76.6 /- 12.4 at baseline). The PR interval remained unchanged (0.17 +/- 0.0 3 sec at six months versus 0.16 +/- 0.02 sec at baseline). There were no significant modifications in any of the laboratory safety parameter s studied (serum creatinine, glucose, cholesterol and transaminase lev els). These data confirm that diltiazem LP 300 mg used as single drug therapy or in combination with another antihypertensive agent is effec tive and exhibits a satisfactory clinical laboratory and electrocardio graphic safety profile.