What is a Washout Period? - Metastatic Breast Cancer Trial Talk

Inside Clinical Trials

In clinical trials, a washout period describes the length of time that someone enrolled in a trial must not receive any treatment before receiving the trial’s experimental therapy. A washout may be required before joining a trial or before changing treatments within a trial. In metastatic breast cancer trials, the washout period is often two to six weeks.

There are two primary reasons researchers require a washout period: to study the effects of the therapy under investigation and to ensure the safety of people enrolled in the trial. However, trials with longer washout periods can be challenging for people with fast-growing or symptomatic tumors.

Because of patients’ and advocates’ concerns about the washout period, clinical trial regulators are working with researchers and patients to determine more appropriate guidelines for washout periods. Read the following articles to learn why washout periods are required, ethical issues related to requiring people to stop treatment, and potential solutions to patient concerns.


Last Modified on March 14, 2021



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