compared with 20 patients per cancer trial, 70 patients per depression trial, and 100 per diabetes trial.
Annual surveys from the Tufts Center for the Study of Drug Development indicate a consistently high turnover rate in the clinical investigator community. Investigators conducting a clinical trial to support a New Drug Application (NDA) or a change in labeling are required to complete FDA’s Form 1527. In 2007, 26,000 investigators registered this form with the FDA, 85 percent of whom participated in only one clinical trial. The issues facing clinical investigators were discussed throughout the workshop, and many participants echoed the theme of the Tufts data—it is difficult to conduct clinical trials in the United States and establish a career as a clinical investigator. While opportunities in clinical investigation can vary depending on whether or not an investigator is working in private practice or academia, for example, the challenges to successfully conducting a clinical trial in the United States are substantial. Making clinical investigation an attractive career option for academics and professionals was mentioned by a number of participants as an important component of any approach to improving the capacity of the clinical trials enterprise in the United States.
In addition to high turnover, the U.S. clinical investigator workforce is subject to an absolute decrease in its ranks. While there has been an annual decline of 3.5 percent in U.S.-based investigators since 2001, there has been an increase in investigators outside the United States. Figure 2-5 reveals that investigators from the rest of the world increased steadily between 1997 and 2007, making up for the decline in North American investigators over the same period. As of 2007, U.S. investigators constituted 57 percent of the global investigator workforce, a decrease from approximately 85 percent in 1997. According to the Tufts data, there are an estimated 14,000 U.S. investigators, compared with an estimated 12,000 investigators outside the United States. Currently, 8.5 percent of investigators are from Central and Eastern Europe, 5.5 percent from Asia, and 5.5 percent from Latin America.
Finally, Krall noted the difference between the role of a clinical investigator (i.e., the person who establishes the hypotheses to test, designs the trial, analyses and reports the results) and that of the individual who finds patients to participate in a trial and collects information about them. The latter role is essential to the ability to carry out research and should be recognized, rewarded, and developed to a greater degree, according to