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Ending Cancer Clinical Trials Early

Most clinical trials run as planned from beginning to end. But sometimes trials are stopped early. For example, the IRB and DSMB may stop a trial if the people taking part are having unexpected and severe side effects. Or they may stop a trial if there is clear evidence that the harms are greater than the benefits.

In some cases, a trial might be stopped because:

  • It is going very well. If there is clear evidence early-on that a new treatment or intervention is effective, then the trial may be stopped so that the new treatment can be made available to others as soon as possible.
  • Enough people cannot be recruited to take part
  • The results of other trials are published that answer the research question or make it irrelevant
  • Reviewed: