Beneficial effects of pumpkin seed soft extract on lower urinary tract symptoms and quality of life in men with benign prostatic hyperplasia: a meta-analysis of two randomized, placebo-controlled trials over 12 months

Abstract

In clinical practice, plant extracts are an option to treat mild-to-moderate lower urinary tract symptoms suggestive of benign prostate hyperplasia (LUTS/BPH). However, only a few herbal extracts have been investigated in long-term placebo-controlled studies. The safety and efficacy of a well-tolerated proprietary pumpkin seed soft extract (PSE) were investigated in two randomized placebo-controlled 12-month studies (Bach and GRANU study). Both trials studied LUTS/BPH patients with an International Prostate Symptom Score (IPSS) ≥13 points at baseline. The Bach study demonstrated positive effects of PSE compared to placebo, but no difference between treatments was observed in the GRANU study. We aimed to assess the efficacy of PSE in a meta-analysis using the patient-level data of these two studies. Pooled analysis was performed in the intention-to-treat set using last-observation-carried-forward (ITT-LOCF). An IPSS improvement of ≥5 points after 12 months of therapy was the predefined response criterion. Logistic regression and ANCOVA models included the covariables treatment group, study, center size, and baseline IPSS. Each analysis was repeated for the per-protocol (PP) set. The ITT/PP analysis sets consisted of 687/485 and 702/488 patients in the PSE and placebo groups, respectively. At the 12-month follow-up, the response rates in the PSE group were 3% (ITT) and 5% (PP) higher than those in the placebo group. The odds ratio of response obtained by logistic regression analysis for comparing PSE versus placebo was 1.2 (95% CI 0.9, 1.5), favoring PSE (ITT- LOCF). For the IPSS change from baseline to 12 months, the ANCOVA estimated difference between the treatment groups was 0.7 points (95% CI 0.1, 1.2) in favor of PSE. The variables study, baseline IPSS, and center size had a relevant influence on treatment response. Although the Bach and the GRANU study showed contradictory results, the analysis in a pooled form still pointed towards an advantage of PSE; namely, more patients in the PSE group showed an IPSS improvement of at least 5 points after 12 months. Therefore, the results of this meta-analysis suggest that patients with moderate LUTS/BPH may benefit from PSE treatment in terms of symptomatic relief.