Comparing Saw Palmetto Extract and Finasteride for BPH Carraro JC, Raynaud JP, Koch G, et al. Comparison of phytotherapy (Permixon®) with finasteride in the treatment of benign prostate hyperplasia: A randomized international study of 1,098 patients. Prostate 1996; 29:231-40. Summary:
A six month, double-blind randomized equivalence study compared the effects for the saw palmetto extract Permixon® to the 5a-reductase inhibitor, finasteride (Proscar®). The study enrolled 1,098 men over the age of 50 years with moderate benign prostatic hyperplasia (BPH) and used the International Prostate Symptom Score (IPSS) as the primary end-point. Men were randomized to receive either 160 mg of Permixon® twice daily or finasteride at a single daily dose of 5 mg. Patients who had received either a-adrenergic receptor antagonists or other phytomedicines (e.g. Pygeum africanum or nettle root) were required to undergo a 2 week washout period prior to beginning treatment. Each patient was evaluated pre-study, and at 6, 13, and 26 weeks. At each visit, peak and mean urinary flow rates were measured, the IPSS was determined, and the patient was asked to complete quality of life and sexual function questionnaires. Additionally, at weeks 13 and 26, patients underwent transrectal and abdominal ultrasound examinations to assess prostatic volume and postvoid residual urine as well as blood chemistries, CBC, and serum prostate-specific antigen (PSA) assay (a baseline PSA was also performed). Of the 1,098 patients randomized to treatment, 553 received Permixon® and 545 received finasteride. Of these 951 completed the study with a total dropout of 16% in the Permixon® group and 11% in the finasteride group. Both treatments were determined to decrease the symptoms of BPH equally. Permixon® decreased the IPSS by 37% compared to 39% for finasteride. Quality of life improved in both groups 38% for Permixon® and 41% for finasteride. Peak urinary flow improved by 25% in the Permixon® compared to 30% in the finasteride group. Finasteride markedly decreased prostatic volume (18%) and PSA (41%) while Permixon® had minimal effect on volume (6% decrease) and no effect on PSA. Patients receiving Permixon® had minimal complaints of decreased libido and impotence while this was more common in the finasteride group. Dysuria was more frequent in the finasteride group while urinary retention was higher for the Permixon® group, but the differences did not exceed 1% for these complications. Commentary:
In the Feb/Mar 1997 TLfDP, I reported on the 3 year, open-label study with 435 BPH patients showing the efficacy of the commercial saw palmetto extract known in Europe as IDS 89.1 In the commentary, I made brief mention of this study which was unpublished at the time. The study was initially presented at the Third International Consultation on BPH in Monaco, June 26-29, 1995. According to an editorial in the same issue of Prostate, the presentation raised quite a stir at the conference.2 The editorial is largely complimentary and brings out some solid criticisms of the study including the lack of a placebo arm and the absence of a placebo run-in period. It is important to note that the study also indicates that finasteride did seem to work more effectively in reducing prostate size in men with larger prostates due to BPH while Permixon® was more effective in reducing the lower urinary tract symptoms (LUTS) of men with smaller prostate size. This is consistent with other studies on finasteride and one of the reasons it has recently come under fire.3 However, it also demonstrates the difficulty in trying to present clear parameters for demonstrating efficacy in the treatment of mild to moderate BPH. The use of LUTS has been recommended as a response to the lack of clarity in diagnosing BPH based on prostate size, urine flow, and subjective symptoms.
Permixon® is the original liposterolic extract of saw palmetto berries (Serenoa repens) created by the pharmaceutical division of Pierre Fabre in France. The hexane extract is comprised of free (90%) and esterified (7%) fatty acids, sterols, polyprenic compounds, and flavonoids. This particular extract was the template for current liposterolic extracts manufactured using either ethanol or CO2 extraction. As is the case with all liposterolic extracts, the therapeutic dose is 320 mg daily. Therapeutic results should be expected in six to eight weeks but it is important to remember that the new rule of thumb for determining clinical efficacy with BPH is six months or longer. As has been reported in previous reviews on saw palmetto, the liposterolic extract is largely devoid of the side effects noted for prescription BPH drugs.
This study establishes another milestone for saw palmetto extract as a viable option in the management of mild to moderate BPH. More long-term trials are still needed as well as the logical comparison of saw palmetto extract with a-adrenergic receptor antagonists. It may be that the diverse mechanisms of action found for saw palmetto and other phytomedicines are the best approach to a condition for which we continue to have poor clinical understanding. References
1. Bach D, Ebeling L. Long-term drug treatment of benign prostatic hyperplasia results of a prospective 3-year multicenter study using Sabal extract IDS 89. Phytomed 1996; 3:105-11.
2. Denis LJ. Editorial review of Comparison of phytotherapy (Permixon®) with finasteride in the treatment of benign prostate hyperplasia: A randomized international study of 1,098 patients. Prostate 1996: 29:241-2.
3. Boyle P, Gould AL. Prostate volume predicts outcome of treatment of BPH with finasteride: Meta-analysis of randomized clinical trials. J Urol 1996; 155:572A.