Surveillance of protocol deviations in Japanese oncology registration trials: a single institute experience

Background The contents and requirements of study protocols vary depending upon each clinical registration trial. This study aims to describe details of protocol deviations in Japanese oncology registration trials. Methods We reviewed deviation reports that were discussed by the Institutional Review Board between 2010 and 2015. Results A total of 499 clinical trials were performed, from which 967 deviations were reported. In the initial 3 years, 445 deviations occurred in 535 ongoing trials, while 522 deviations occurred in 876 trials in the subsequent 3 years. The frequency of deviations related to visit, examination, treatment, and others was 189 (19.5%), 446 (46.1%), 275 (28.4%), and 57 (5.9%), respectively. Serious deviations were common at the time of registration of trials and during treatment. The deviations were attributable to the institution (n = 520), subject (n = 93), sponsor (n = 28), schedule management (n = 162), disease condition (n = 95), and others (n = 69). Conclusion This study showed the number and detail responsible factors of protocol deviations. Our findings support to distinguish between the measures to reduce the serious deviations and to reduce the overall number of deviations.