Patients with localized prostate cancer were followed to progression or maximum 24 weeks after a single injection in one lobe of 2-8 mL ready-made paste (corresponding to 400-1600 mg 2-Hydroxyflutamid). Progression was defined as an increase in PSA by \> 25% over baseline or on-treatment nadir.Among the 24 patients the primary endpoint, plasma PSA nadir, was reached by 20 patients (Responders). Efficacy was measured primarily as PSA nadir, and secondly as time to PSA nadir and prostate volume change. Safety was monitored throughout the whole study period.