What You Need to Know About Washout Periods - 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 treatment. A washout may be required before joining a trial or before changing treatments within a trial. In MBC trials, the washout period is often two to six weeks.

There are two main reasons researchers require a washout period: to study the effects of only the treatment being studied and to ensure participant safety by removing the possibility of drugs interacting with each other in unexpected ways. However, trials with longer washout periods can be challenging for people with fast-growing tumors or tumors that are causing symptoms and affecting quality of life.

Because of patient and advocate concerns about the washout period, clinical trial regulators are working with researchers and patients to determine more appropriate guidelines for washout periods. In April 2024, the Food and Drug Administration (FDA) issued new guidelines about washout periods.

Read the following articles to learn about why washout periods are required, concerns around requiring people to stop treatment, potential solutions to prespecified washout periods, and the FDA’s new guidance.

What is the Washout Period and Why is it Needed?
Experts Comment on the New Guidelines From the FDA About Washout Periods


Last Modified on July 1, 2024



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