Emerging drugs for the treatment of benign prostatic obstruction.
OBJECTIVE To assess the clinical efficacy and safety of the combined alpha1- and postsynaptic alpha2-blocker GYKI-16084 compared to placebo during a 28-day active treatment of patients with benign prostatic hyperplasia (BPH). PATIENTS AND METHODS After a 28-day placebo run-in phase, 7.5 and 15 mg GYKI-16084 or placebo were administered twice daily for 28 days to patients with BPH in a randomized single-blind Phase II study. Efficacy was primarily determined by changes in the American Urological Association (AUA) symptom scores and maximum urinary flow (Q(max)), while safety was assessed by orthostatic changes and adverse-event profile. A simplified International Index of Erectile Function questionnaire was used to assess effects on erectile function. RESULTS Data from 63 patients were evaluated; the decrease in the AUA score during the active phase was greater in the 15 mg group (-6.05, -32.7%) than in the placebo (-4.3, 22.7%) or 7.5 mg (-3.55, -19.5%) groups. Q(max) improved in both active treatment groups (+3.3 and +2.16 mL for the 7.5 and 15 mg groups, respectively) compared to placebo (+1.29 mL). None of the drug-related adverse events associated with selective alpha1-blockers were reported. CONCLUSION The combined alpha1- and postsynaptically selective alpha2-blocker GYKI-16084 significantly improved the AUA symptom scores and increased Q(max) in patients with BPH, without inducing any adverse reaction, orthostatic changes or erectile dysfunction.