RESUMO
BACKGROUND: The recommendations in clinical guidelines are based on clinical trial findings and expert opinion. The influence of drug companies on these two factors is illustrated with two examples. METHODS: A judicially ordered expert review revealed that the market authorization holder (MAH) of gabapentin manipulated study data. Gabapentin was, therefore, chosen as an example for this article to analyze whether manipulated data serve as a basis for recommendations in German clinical guidelines. A search was carried out for manipulated publications on gabapentin that found their way into guidelines published by the Association of Scientific Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF). To analyze the possible effects of financial ties between guideline authors and drug companies, the S3 guideline on the treatment of psoriasis vulgaris with efalizumab was compared with guidelines whose authors had no conflicts of interest. One of the authors of this article had noted variable prescribing practices for psoriasis among dermatologists while carrying out an economic assessment for a German state Association of Statutory Health Insurance Physicians. RESULTS: The data that had been manipulated by the MAH of gabapentin served as a basis for recommendations to prescribe gabapentin in guidelines that were published by the AWMF. Efalizumab was judged more favorably in the S3 guideline than in a guideline issued by the National Institute of Health and Care Excellence: for example, the evidence for it was judged as good, the use of efalizumab for induction and combination therapy in psoriasis vulgaris was recommended, and efalizumab was said to improve patients' health-related quality of life. CONCLUSION: Public access to all trial data must be ensured so that independent evaluations are possible. We take the view that the responsibility for creating guidelines should be borne by authors and organizations that do not have any conflicts of interest.