STUDY OF THE PHARMACOKINETIC DOSE-LINEARITY OF A SUSTAINED-RELEASE FORMULATION OF BUNAZOSIN (E1015) IN HEALTHY-VOLUNTEERS

The dose-linearity of the pharmacokinetics of sustained-release bunazo sin was studied in 12 healthy volunteers following single oral dose ad ministration of a sustained-release formulation of bunazosin (Bunazosi n Retard(R); E1015) 3 to 18mg in an incremental fashion at weekly inte rvals. Mean peak plasma bunazosin concentration (5.1 to 38.6 mug/L) an d mean area under the concentration-time curve from 0 to 72 hours (70. 6 to 463.9 mug/L . h) were linearly related to dose (r = 0.82). Neithe r time to peak plasma concentration, plasma clearance, nor mean reside nce time were significantly correlated with dose. Symptomatic postural hypotension was evident with the higher doses of bunazosin.