When the clinical trial is finished

Some clinical trials go on for many years. While your part in the trial may be done, all participants have to finish treatment and follow-up before any results can be analyzed. This could take a while because not everyone started at the same time. When the trial is over, it takes time for the researchers to look carefully at all the results before making any conclusions.

An endpoint is something that researchers can measure that helps the researchers to find out how effective the new treatment is. For example, researchers may compare the measurements of CT scans taken before, during and after treatment to see if the tumour has gotten smaller, has gotten bigger or hasn’t changed at all. Survival is another endpoint for many clinical trials. Overall survival is the amount of time that people in the trial are still alive from the time that the experimental treatment started. Other survival measurements include progression-free survival and disease-free survival.

The results of clinical trials are often presented at scientific meetings and published in scientific journals. A really important finding may also be reported in the media.

Approving a new drug or treatment

After clinical trials show that a new drug or treatment for cancer is safe and effective, it is submitted to Health Canada for approval. Once approved, doctors can then recommend this treatment to people with cancer.

It often takes more than 10 years for a new drug or treatment to go from preclinical trials, through clinical trials, to the approval process before it is available as a standard treatment to people with cancer.

Expert review and references

  • Delacruz A & McCall S . Principles of cancer clinical trials. Yarbro CH, Wujcki D, Holmes Gobel B, (eds.). Cancer Nursing: Principles and Practice. 8th ed. Burlington, MA: Jones and Bartlett Learning; 2018: 9: 227-242.
  • National Cancer Institute. What are clinical trials?. 2016: https://www.cancer.gov/about-cancer/treatment/clinical-trials/what-are-trials.
  • Simon RM . Design and analysis of clinical trials. DeVita VT Jr, Lawrence TS, Rosenberg SA. Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 36:398-415.

Medical disclaimer

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