Potential role of postmarketing research

To consider beneficial and adverse effects during one and the same postmarketing study seems to be perfectly logical, but is difficult to accomplish from a methodological point of view. This is caused by the particular conditions and design of clinical trials in Phases I-III as opposed to those in the postmarketing phase. Postmarketing research becomes to a large extent an activity independent from the pharmaceutical company, yielding information about groups of patients, concomitant therapies and many other factors that were only partly considered in Phases I-III. The heterogeneity and volume of data produced after marketing, requires for their intelligent integration and interpretation, an effort to assure a minimum quantity of data in every case report or in every study and of acceptable quality. Another requirement is the wider use of generally accepted terminologies, criteria for categorization etc. Without these prerequisites a lot of information is being lost or risks being misinterpreted. More attention to these factors would considerably improve the cost-efficiency of postmarketing research.