Zusammenfassung
Als Voraussetzung für die Zulassung neuer Antidepressiva wird von den Arzneimittelbehörden
nach wie vor der Nachweis einer signifikant besseren Wirkung im Vergleich zu Plazebo
in kontrollierten Studien gefordert. Demgegenüber stehen - nicht zuletzt aus den Reihen
der Ärzteschaft - ethische Bedenken hinsichtlich eines möglichen zusätzlichen Risikos,
welchem die Kontrollgruppe durch das damit verbundene Unterbleiben einer Behandlung
mit Antidepressiva ausgesetzt sei. Der vorliegende Artikel gibt einen Überblick über
häufig vorgebrachte Argumente pro und kontra Plazebokontrollen in Antidepressiva-Studien,
behandelt die Problematik der verschiedenen Wirkfaktoren von Antidepressiva und Plazebo
in der Behandlung der Depression und diskutiert abschließend einige Vorschläge zur
Planung plazebokontrollierter Studien, welche deren Aussagekraft verbessern können
und dabei das Risiko für den Patienten so gering wie möglich halten. Eine weltweite
Lösung des Problems ist grundsätzlich anzustreben. Das aus der Deklaration von Helsinki
vereinzelt herausgelesene Verbot einer Verwendung von Plazebo in Antidepressiva-Studien
sollte so lange ausgesetzt werden, bis Antidepressiva mit einer klareren Überlegenheit
gegenüber Plazebo zur Verfügung stehen.
Abstract
For the approval of a new antidepressant for clinical use drug authorities still demand
the proof of a significantly superior efficacy of the compound over placebo shown
in controlled comparison studies. On the other side serious ethical concerns have
been raised upon the use of placebos in clinical trials with depressed patients in
that this would implicitly mean a withholding of an efficacious treatment from patients
in the control groups of such trials. This article summarises frequently quoted arguments
for and against placebo use in antidepressant clinical trials focussing on the specific
issues involved in the therapeutic effect of antidepressants and placebos in depressed
patients and discusses measures that might contribute to study designs that may better
evaluate the true efficacy of a new drug while keeping the risk for the individual
patient at the lowest possible level. A worldwide solution of the problem is clearly
called for. A ban of placebos in antidepressant trials as it might be derived from
the Declaration of Helsinki should be postponed until antidepressants with a more
convincing superiority over placebo have been developed.
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Dr. E. A. Deisenhammer
Universitätsklinik für Psychiatrie
Anichstraße 35
6020 Innsbruck
Österreich
Email: eberhard.deisenhammer@uibk.ac.at