Are drug clinical trials broadly applicable? The case of staphylococcal bacteraemia

Clinical trials are traditionally designed by pharmaceutical companies or clinical research organizations to address the requirements and regulations of national regulatory agencies such as the US Food and Drug Administration. The criteria for enrolment are strict and well-defined, necessitating the screening of large numbers of individuals for each subject enrolled. Common exclusion criteria include extremes of age and weight, pregnancy, previous treatment with effective antibiotics for the same infection, organ dysfunction, malignant diseases with a short survival time, advanced HIV etc. In clinical trials, cost, length of hospital stay, complexity of drug administration and patient and family preferences are rarely considered, and seldom make their way into the report of the trial. The limited patient population and under-representation of sicker, older individuals leads to underestimation of drug toxicity and overestimation of efficacy. Postmarketing studies are commonly used to document adverse reactions, but they are not supported by industry and receive limited funding. We chose to evaluate the applicability to general staphylococcal bacteraemia patient populations of clinical trials comparing antimicrobial agents used to treat Staphylococcus aureus bacteraemia.