In an open-label extension of a randomized, double-blind clinical trial, the long-term efficacy and tolerability of a fixed combination of 160 mg Sabal fruit extract WS 1473 and 120 mg Urtica root extract WS 1031 per capsule (PRO 160/120) were investigated in elderly men with moderate or severe lower urinary tract symptoms (LUTS) caused by benign prostatic hyperplasia (BPH). Two hundred and fifty-seven patients were randomly treated with 2 x 1 capsule/day PRO 160/120 or placebo for 24 weeks, followed by a 24-week control period and a 48-week follow-up period in which all patients received PRO 160/120. Efficacy measures included the assessment of LUTS [International Prostate Symptom Score ((I-PSS) self-rating questionnaire] and uroflow and sonographic parameters. Two hundred and nineteen subjects participated in the follow-up. Between baseline and end of observation (week 96) the I-PSS total score was reduced by 53% (P < 0.001), peak and average urinary flow increased by 19% (P < 0.001), and residual urine volume decreased by 44% (P = 0.03). The incidence of adverse events during follow-up was one in 1,181 treatment days; in only one event a causal relationship with intake of PRO 160/120 could not be excluded. Treatment with PRO 160/120 thus provides a clinically relevant benefit over a period of 96 weeks.