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Exploratory evaluation of a commercially available Japanese medical record database as an external control for comparative clinical trials in new drug development: Amyotrophic lateral sclerosis

Clinical trials with internal control groups may not always be feasible, especially for rare diseases. We performed an exploratory evaluation of the Medical Data Vision Co., Ltd. (MDV) medical record database as an external control in clinical trials for drug development. Survival curves for amyotrophic lateral sclerosis (ALS) patients in the MDV database were compared with those for ALS patients in phase 3 trials of riluzole inside (1997) and outside (1996) Japan. Considering the time difference between MDV data collection (2008–2016) and riluzole trials (1996–1997), survival curves for ALS patients in the riluzole‐prescribed group in the MDV database and the placebo group in a celecoxib phase 3 trial (2006) in which 71% of patients received riluzole as first‐line treatment were also compared. The MDV database survival curves for the riluzole‐not prescribed and riluzole‐prescribed groups differed markedly from those for placebo groups and riluzole groups in two riluzole phase 3 trials. The survival curve for the placebo group in a celecoxib phase 3 trial was similar to that for the riluzole‐prescribed group in the MDV database until around 300 days after the start of observation. Our results were consistent with reports that patients diagnosed with ALS more recently survived longer and had slower disease progression than those diagnosed earlier. External comparative controls should consist of patient data collected in the same time period as when clinical trials were performed if the natural history of a disease is changing.