title: The assessment of efficacy, toxicity and quality of care in long-term drug treatment.
abstract: Drug studies in man are usually divided into four phases. The first phase is to establish that the drug has a pharmacological action in man and in which dose range it occurs. The second phase is a study of the therapeutic effect of the drug in small numbers of closely observed patients. The third phase consists of large-scale studies which may involve hundreds or thousands of patients; such studies are designed to accumulate less detailed information about efficacy and to provide information about low frequency toxic events. At the end of this stage the drug is submitted to a regulatory body for a license to market it. Information derived from these studies usually has several important deficiencies. There is unlikely to be much evidence about the efficacy of the drug in relation to that of other substances used to treat the same condition. The carefully regulated conditions of the clinical trial may bear little relationship to the way the drug will be used in practice. Most important, the evidence obtained on efficacy may relate chiefly to the pharmacological action of the drug, e.g. in lowering blood pressure or blood sugar, or reducing inflammation, and may not bear directly upon therapeutic outcome. For these reasons much attention is being focused on monitoring of the way drugs are used after marketing. To provide evidence of therapeutic efficacy may require studies of such large scale and high cost that they are beyond the research of individual pharmaceutical companies and will require national or international action. Monitoring of the way drugs are used inevitably means studying not just the performance of the drug but also of the doctors who prescribe it. Studies that have been made of the quality of care of patients treated with anti-hypertensive drugs and those requiring anticoagulants are not reassuring concerning the general level of such quality.
mesh_terms: D003362:Cost-Benefit Analysis; D004341:Drug Evaluation; D004358:Drug Therapy / Q000592:standards*; D004363:Drug Utilization; D064420:Drug-Related Side Effects and Adverse Reactions; D006801:Humans; D007880:Legislation, Drug; D008004:Licensure; D004364:Pharmaceutical Preparations / Q000138:chemical synthesis; D010600:Pharmacology; D011787:Quality of Health Care; D012106:Research; D014116:Toxicology; D006113:United Kingdom; D014481:United States
chemical_list: D004364:Pharmaceutical Preparations