Potential for Conflict of Interest in the Evaluation of Suspected Adverse Drug Reactions:  A Counterpoint

Health care practitioners and patients seek safe and effective drugs. However, no drug is completely safe; all drugs have toxic effects that must be balanced with their benefits in deciding whether they should be marketed or used in any given person. To inform such decisions, the United States relies on a drug approval system whereby preclinical studies precede 3 phases of clinical studies. Collectively, these usually include 500 to 3000 exposed patients and 2 or more confirmatory trials, demonstrating before marketing that a drug is effective and reasonably safe for its recommended use.¹ Thus, adverse reactions occurring in 1% or more of exposed patients are usually well described upon marketing. However, rarer adverse reactions are not well characterized until after marketing.² This reflects a deliberate societal decision to balance delays in access to new drugs with delays in information about rare adverse reactions. To provide the missing information, the United States maintains a postmarketing surveillance system including passive collection of spontaneous reports of adverse drug reactions (ADRs) to generate signals of possible adverse drug events. This is supplemented by formal pharmacoepidemiology studies testing those hypotheses, confirming or disproving potential signals from the spontaneous reporting system (SRS).²