The international terazosin trial: a multicentre study of the long-term efficacy and safety of terazosin in the treatment of benign prostatic hyperplasia. The ITT Group.

OBJECTIVE

To evaluate the long-term efficacy and safety of terazosin in the treatment of benign prostatic hyperplasia (BPH).

METHODS

Thirty-three sites in 13 countries enrolled men with BPH who had an International Prostate Symptom Score (IPSS) > or = 12 [corrected]. After a 2-week, no-treatment lead-in period and a 26-week, single-blind treatment period, patients responding to terazosin were randomly assigned to receive either terazosin or placebo for a 24-week, double-blind withdrawal period.

RESULTS

Of the initial 427 patients enrolled, 378 were evaluable, 273 of whom completed the single-blind period, of which 186 patients were randomized. During the single-blind treatment period, IPSS, quality-of-life score (QOL), peak flow rate (PFR), and nocturia score (NOC) improved significantly (p < or = 0.05). During the double-blind withdrawal period, IPSS, QOL, PFR, and NOC deteriorated significantly in the placebo group compared with the terazosin group. The most common adverse event resulting in premature termination from the study was dizziness. There were no clinically important mean reductions in diastolic blood pressure (DBP) for patients normotensive at baseline. Terazosin significantly reduced mean DBP in hypertensive patients during the single-blind period and maintained the reduction during the double-blind period.

CONCLUSION

Treatment with terazosin has a beneficial effect on BPH, continuing for at least 12 months, and can be safely considered for medium- to long-term use in those who benefit.