"Once-daily, low-dose aspirin did not significantly reduce the risk of the composite outcome of cardiovascular death, nonfatal stroke, and nonfatal myocardial infarction among Japanese patients 60 years or older with atherosclerotic risk factors...
[Hence] The [JPPP] study was terminated early by the data monitoring committee after a median follow-up of 5.02 years (interquartile range, 4.55–5.33) based on likely futility...We plan to conduct further analyses to establish whether aspirin had beneficial effects in particular subgroups of patients or if there were beneficial effects with respect to cancer prevention."
Is this the ethics committee-equivalent of first shoot, then ask questions? Why would you kill the study for futility before conducting a full analysis including cancer? I know that there are confounding issues if cancer was only a secondary endpoint, but at some point something must have gone ridiculously wrong, be it initial study design or the decision by the ethics committee. Perhaps, we are just dealing with sloppy writing, the monitoring committee knowing that cancer was unchanged, and the authors hoping that a signal will emerge now or in the future. Something isn't quite right here.
Either way, it'd be a travesty if there turns out to be a signal, yet the trial (n~14 000) was stopped precociously.
1. Ikeda, Yasuo, Kazuyuki Shimada, Tamio Teramoto, Shinichiro Uchiyama, Tsutomu Yamazaki, Shinichi Oikawa, Masahiro Sugawara, et al. 2014. “Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Japanese Patients 60 Years or Older with Atherosclerotic Risk Factors: A Randomized Clinical Trial.” JAMA 312 (23): 2510–20. doi:10.1001/jama.2014.15690.