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Neurourology and Urodynamics 26:464 (2007) EDITORIAL COMMENT Dear Dr. Edgar and colleagues, I read your comprehensive and interesting article review- ing the experimental data relating to the possible mechanisms underlying the potential clinical activity of Pygeum africanum extract. I wish to clarify the potential clinical applicability of these interesting data. Whilst there is interest in phytotherapy of BPH/LUTS, particularly within the framework of complemen- tary medicine, clearly it is important to critically assess the evidence base supporting the use of phytotherapy. As you know plant extracts are complex mixtures of various agents and are in a sense unique, as the extraction procedures may differ even if the preparations originate from the same plant and the exact compositions of the preparations vary and are only partially chemically defined. The clinical efficacy of the P. africanum extract (Tadenan 1 ) has been evaluated in placebo-controlled 1–5 and in open studies 6,7 using both subjective and objective assessment criteria. However, these studies were performed years ago and do not meet the strict guidelines recommended by the International Consultation Conferences. Abbou 8 reported the results of a randomized trial compar- ing Alfuzosin to an extract from P. africanum: 331 patients completed the 8-week study. Alfuzosin was more effective than P. africanum with regard to peak flow rate, decrease of residual urine, and improvement of storage symptom score. A systematic review and quantitative meta-analysis has been performed on the studies of the therapeutic efficacy and tolerability of P. africanum in men with lower urinary tract symptoms (LUTS); where it was used either alone or in combination with other phytotherapeutic agents with a control group who received placebo or other pharmacological therapy and where the treatment duration was at least 30 days. Compared with placebo in six studies, P. africanum provided a moderate improvement in LUTS and flow rate. Nocturia was reduced by 19% and residual urine volume by 24%; peak urine flow was increased by 23%. Adverse effects due to P. africanum were mild and similar to placebo. The overall dropout rate was 12% and was similar for P. africanum (13%), placebo (11%), and other controls (8%; P ¼ 0.4 versus placebo and P ¼ 0.5 versus other controls). 9 Clearly the literature on P. africanum for the treatment of male LUTS is limited by the short duration of studies and the variability in study design, the type of phytotherapeutic preparation, and the nature of reported outcomes. In the light of the limited clinical data I would agree with your observa- tions that neither in vitro nor in vivo can be extrapolated to man and therefore have little clinical relevance. You clearly identify the need for adequately powered double-blind placebo-controlled studies of sufficient duration to answer these questions and on behalf of the WHO pharmacotherapy committee I would strongly encourage these to be carried out, before any meaningful conclusions can be drawn. Christopher Chapple* Editor-in-Chief REFERENCES 1. Bartlet A, Albrecht J, Aubert A, et al. Efficacy of Pygeum africanum extract in the treatment of micturitional disorders due to benign prostatic hyperplasia: evaluation of objective and subjective parameters: A multicentre, placebo- controlled double-blind trial. Wien Klin Wochenschr 1990;102:667–73. 2. Dufour B, Choquenet C, Revol M, et al. Controlled study of the effects of Pygeum africanum extract on the functional symptoms of prostatic adenoma. Ann Urol (Paris) 1984;193–5. 3. Maver A. Traitement m edical de l’hypertrophie fibroade ´nomateuse de la prostate a ` l’aide d’une nouvelle substance ve ´ge ´tale. Minerva Med 1972;63: 2126–36. 4. Ranno S, Minaldi G, Viscusi G, et al. Efficacia e tollerabilita ` del trattamento dell’adenoma prostatico con Tadenan 50. Prog Med 1986;42:165–9. 5. Rizzo M, Tosto A, Paoletti MC. Terapia medica dell’adenoma della prostata. valutazione clinica comparativa tra estratto di Pygeum africanum ad alte dosi e placebo. Farmacia Terapia 1985;2:105–10. 6. Andro MC, Riffaud JP. Pygeum Africanum extract for the treatment of patients with benign prostatic hyperplasia; A review of 25 years of published experience. Curr Therap Res 1995;56:796–817. 7. Mandressi S, Tarallo U, Maggioni A, et al. Medical treatment of benign prostatic hyperplasia: Efficacy of the extract Serenoa repens (Permixon 1 ) compared to that of the extract of Pygeum africanum and a placebo. Urologia 1983;50:752–8. 8. Abbou CC, Hoznek A, McCarthy C, et al. Alfuzosin, an uroselective alpha-1- blocker versus Pygeum Africanum, a plant extract: A randomised controlled trial in patients with symptomatic benign prostatic hypertrophy (BPH). Eur Urol 1996;30: Abstr 241. 9. Ishani A, MacDonald R, Nelson D, et al. Pygeum africanum for the treatment of patients with benign prostatic hyperplasia: A systematic review and quantitative meta-analysis. Am J Med 2000;109:654–64. Re: Edgar AD, Levin R, Constantinou CE, et al. 2007. A Critical Review of the Pharmacology of the Plant Extract of Pygeum africanum in the Treatment of LUTS. Neurourol Urodynam 26:458–463 *Correspondence to: Christopher Chapple, Neuorurology & Urodynamics Editor- ial Office, Room H26, H-Floor, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 21F, United Kingdom. E-mail: [email protected]. Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/nau.20452 ß 2007 Wiley-Liss, Inc.

Re: Edgar AD, Levin R, Constantinou CE, et al. 2007. A critical review of the pharmacology of the plant extract of Pygeum africanum in the treatment of LUTS. Neurourol Urodynam 26:458–463

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Neurourology and Urodynamics 26:464 (2007)

EDITORIAL COMMENT

Dear Dr. Edgar and colleagues,I read your comprehensive and interesting article review-

ing the experimental data relating to the possible mechanismsunderlying the potential clinical activity of Pygeum africanumextract.

I wish to clarify the potential clinical applicability of theseinteresting data. Whilst there is interest in phytotherapy ofBPH/LUTS, particularly within the framework of complemen-tary medicine, clearly it is important to critically assess theevidence base supporting the use of phytotherapy.

As you know plant extracts are complex mixtures ofvarious agents and are in a sense unique, as the extractionprocedures may differ even if the preparations originate fromthe same plant and the exact compositions of the preparationsvary and are only partially chemically defined.

The clinical efficacy of the P. africanum extract (Tadenan1)has been evaluated in placebo-controlled1–5 and in openstudies6,7 using both subjective and objective assessmentcriteria. However, these studies were performed years ago anddo not meet the strict guidelines recommended by theInternational Consultation Conferences.

Abbou8 reported the results of a randomized trial compar-ing Alfuzosin to an extract from P. africanum: 331 patientscompleted the 8-week study. Alfuzosin was more effectivethan P. africanum with regard to peak flow rate, decrease ofresidual urine, and improvement of storage symptom score.

A systematic review and quantitative meta-analysis hasbeen performed on the studies of the therapeutic efficacy andtolerability of P. africanum in men with lower urinary tractsymptoms (LUTS); where it was used either alone or incombination with other phytotherapeutic agents with acontrol group who received placebo or other pharmacologicaltherapy and where the treatment duration was at least30 days. Compared with placebo in six studies, P. africanumprovided a moderate improvement in LUTS and flow rate.Nocturia was reduced by 19% and residual urine volume by24%; peak urine flow was increased by 23%. Adverse effectsdue to P. africanum were mild and similar to placebo. Theoverall dropout rate was 12% and was similar for P. africanum(13%), placebo (11%), and other controls (8%; P¼ 0.4 versusplacebo and P¼ 0.5 versus other controls).9

Clearly the literature on P. africanum for the treatment ofmale LUTS is limited by the short duration of studies and thevariability in study design, the type of phytotherapeuticpreparation, and the nature of reported outcomes. In the lightof the limited clinical data I would agree with your observa-tions that neither in vitro nor in vivo can be extrapolated toman and therefore have little clinical relevance. You clearlyidentify the need for adequately powered double-blindplacebo-controlled studies of sufficient duration to answerthese questions and on behalf of the WHO pharmacotherapycommittee I would strongly encourage these to be carried out,before any meaningful conclusions can be drawn.

Christopher Chapple*Editor-in-Chief

REFERENCES

1. Bartlet A, Albrecht J, Aubert A, et al. Efficacy of Pygeum africanum extract inthe treatment of micturitional disorders due to benign prostatic hyperplasia:evaluation of objective and subjective parameters: A multicentre, placebo-controlled double-blind trial. Wien Klin Wochenschr 1990;102:667–73.

2. Dufour B, Choquenet C, Revol M, et al. Controlled study of the effects ofPygeum africanum extract on the functional symptoms of prostatic adenoma.Ann Urol (Paris) 1984;193–5.

3. Maver A. Traitement m�edical de l’hypertrophie fibroadenomateuse de laprostate a l’aide d’une nouvelle substance vegetale. Minerva Med 1972;63:2126–36.

4. Ranno S, Minaldi G, Viscusi G, et al. Efficacia e tollerabilita del trattamentodell’adenoma prostatico con Tadenan 50. Prog Med 1986;42:165–9.

5. Rizzo M, Tosto A, Paoletti MC. Terapia medica dell’adenoma della prostata.valutazione clinica comparativa tra estratto di Pygeum africanum ad alte dosie placebo. Farmacia Terapia 1985;2:105–10.

6. Andro MC, Riffaud JP. Pygeum Africanum extract for the treatment of patientswith benign prostatic hyperplasia; A review of 25 years of publishedexperience. Curr Therap Res 1995;56:796–817.

7. Mandressi S, Tarallo U, Maggioni A, et al. Medical treatment of benignprostatic hyperplasia: Efficacy of the extract Serenoa repens (Permixon1)compared to that of the extract of Pygeum africanum and a placebo. Urologia1983;50:752–8.

8. Abbou CC, Hoznek A, McCarthy C, et al. Alfuzosin, an uroselective alpha-1-blocker versus Pygeum Africanum, a plant extract: A randomised controlledtrial in patients with symptomatic benign prostatic hypertrophy (BPH). EurUrol 1996;30: Abstr 241.

9. Ishani A, MacDonald R, Nelson D, et al. Pygeum africanum for the treatment ofpatients with benign prostatic hyperplasia: A systematic review andquantitative meta-analysis. Am J Med 2000;109:654–64.

Re: Edgar AD, Levin R, Constantinou CE, et al. 2007.A Critical Review of the Pharmacology of the Plant Extract of

Pygeum africanum in the Treatment of LUTS.Neurourol Urodynam 26:458–463

*Correspondence to: Christopher Chapple, Neuorurology & Urodynamics Editor-ial Office, Room H26, H-Floor, Royal Hallamshire Hospital, Glossop Road,Sheffield S10 21F, United Kingdom. E-mail: [email protected] online in Wiley InterScience(www.interscience.wiley.com)DOI 10.1002/nau.20452

� 2007 Wiley-Liss, Inc.