A multicentric, placebo-controlled, double-blind clinical trial of beta-sitosterol (phytosterol) for the treatment of benign prostatic hyperplasia. German BPH-Phyto Study group. Randomised, placebo-controlled, double-blind clinical trial of beta-sitosterol in patients with benign prostatic hyperplasia. Beta-sitosterol Study Group. A double-blind trial of the effect of beta-sitosteryl glucoside (WA184) in the treatment of benign prostatic hyperplasia.
To report the results of a double-blind, placebo-controlled trial to evaluate Azuprostat, a beta-sitosterol, in patients with symptoms of outlet obstruction caused by benign prostatic hyperplasia (BPH).
                A randomized, double-blind and placebo-controlled clinical trial was conducted to assess the efficacy and safety of 130 mg free beta-sitosterol (phytosterol) daily, using the international prostate symptom score (IPSS) as the primary outcome variable. In total, 177 patients with BPH were recruited for 6 months of treatment in 13 study centres. In addition to the relative difference in the IPSS, changes in quality of life, peak urinary flow rate (Qmax) and post-void residual urinary volume (PVR) were recorded. The drug used in the trial consisted of a chemically defined extract of phytosterols, derived for example from species of Pinus, Picea or Hypoxis, with beta-sitosterol as the main component.
                There were significant (P < 0.01) improvements over placebo in those treated with beta-sitosterol; the mean difference in the IPSS between placebo and beta-sitosterol, adjusted for the initial values, was 5.4 and in the quality-of-life index was 0.9. There were also significant improvements in the secondary outcome variables, with an increase in Qmax (4.5 mL/s) and decrease in PVR (33.5 mL) in favour of beta-sitosterol when adjusted for the changes after placebo.
                These results show that beta-sitosterol is an effective option in the treatment of BPH. Medical treatments have become available for benign hypertrophy of the prostate, including alpha-receptor blocking agents and 5-alpha-reductase inhibitors. Drugs derived from plants, for which no precise mechanism of action has been described, are widely used for this purpose in Europe. In a randomised, double-blind, placebo-controlled multicentre study, 200 patients (recruited between April and October 1993) with symptomatic benign prostatic hyperplasia were treated with either 20 mg beta-sitosterol (which contains a mixture of phytosterols) three times per day or placebo. Primary end-point was a difference of modified Boyarsky score between treatment groups after 6 months; secondary end-points were changes in International Prostate Symptom Score (IPSS), urine flow, and prostate volume. Modified Boyarsky score decreased significantly with a mean of -6.7 (SD 4.0) points in the beta-sitosterol-treated group versus -2.1 (3.2) points in the placebo group p < 0.01. There was a decrease in IPSS (-7.4 [3.8] points in the beta-sitosterol-treated group vs -2.1 [3.8] points in the placebo group) and changes in urine flow parameters: beta-sitosterol treatment resulted in increasing peak flow (15.2 [5.7] mL/s from 9.9 [2.5] mL/s), and decrease of mean residual urinary volume (30.4 [39.9] mL from 65.8 [20.8] mL). These parameters did not change in the placebo group (p < 0.01). No relevant reduction of prostatic volume was observed in either group. Significant improvement in symptoms and urinary flow parameters show the effectiveness of beta-sitosterol in the treatment of benign prostatic hyperplasia. Cholesterol-lowering agents are still used in some countries for the treatment of benign prostatic hyperplasia (BPH). A randomized, double-blind, placebo-controlled urodynamic study, carried out on 53 patients with proven outflow obstruction, has failed to prove that the drug, beta-sitosteryl beta-D-glucoside (WA184), is superior to placebo in the treatment of outflow obstruction due to BPH when administered at a dose of 0.3 mg/day. Possible reasons for this include an insufficient dose and duration of treatment (this drug is known to have a potent effect on cholesterol metabolism in the prostate) and the predominantly stromal pathological changes which characterize BPH and which may be unaffected by such agents.
The evidence suggests non-glucosidic B-sitosterols improve urinary symptoms and flow measures. Their long term effectiveness, safety and ability to prevent BPH complications are not known.