The Value of Observational Cohort Studies for Cancer DrugsRandomized controlled trials - the gold standard for clinical drug evaluation -can't always predict adverse events in real-world settings. For the new cancer therapies, observational cohort studies (OCSs) can help evaluate their effects in broader populations and provide valuable information for future clinical trials.

摘要

The gold standard for determining the efficacy and safety of a new cancer therapy is the randomized controlled trial (RCT) (Silverman 2009). Randomization helps balance groups so that differences in outcomes can be attributed to the therapy being tested. RCTs, however, are challenging to conduct because of limited patient and financial resources, time constraints, competing studies, and changing physician and patient interest. Further, when RCTs are completed and produce positive (or negative) results, their findings may be limited in real-world applicability - cancer patients may not always mirror the characteristics of the patient group treated on study because of specific enrollment criteria, study-related procedures, ethical dilemmas, and differences inherent in those patients who chose to participate in the clinical trial. Consequently, how a new drug is used in practice may not always reflect how that drug was used on study, potentially affecting its real-world efficacy and safety profiles. Indeed, a major drawback of RCTs is their inability to definitively evaluate the safety profile of new cancer therapies - the true incidence of drug-related toxicities may not be determined, and newly emergent or rare events may go unreported (Avorn 2007, Ray 2003).