TY - JOUR AU - Guilloteau, Adrien AU - Abrahamowicz, Michal AU - Boussari, Olayide AU - Jooste, Valérie AU - Aparicio, Thomas AU - Quantin, Catherine AU - Le Malicot, Karine AU - Binquet, Christine PY - 2021 DA - 2021/01/09 TI - Impact of time-varying cumulative bevacizumab exposures on survival: re-analysis of data from randomized clinical trial in patients with metastatic colo-rectal cancer JO - BMC Medical Research Methodology SP - 14 VL - 21 IS - 1 AB - As cancer treatment, biotherapies can be as effective as chemotherapy while reducing the risk of secondary effects, so that they can be taken over longer periods than conventional chemotherapy. Thus, some trials aimed at assessing the benefit of maintaining biotherapies during chemotherapy-free intervals (CFI). For example, the recent PRODIGE9 trial assessed the effect of maintaining bevacizumab during CFI in metastatic colorectal cancer (mCRC) patients. However, its analysis was hindered by a small difference of exposure to the treatment between the randomized groups and by a large proportion of early drop outs, leading to a potentially unbalanced distribution of confounding factors among the trial completers. To address these limitations, we re-analyzed the PRODIGE9 data to assess the effects of different exposure metrics on all-cause mortality of patients with mCRC using methods originally developed for observational studies. SN - 1471-2288 UR - https://doi.org/10.1186/s12874-020-01202-9 DO - 10.1186/s12874-020-01202-9 ID - Guilloteau2021 ER -