Keytruda (pembrolizumab) is a brand-name intravenous infusion that’s prescribed for certain types of cancer. It works by blocking activity at specific receptors which help prevent cancer cells from growing.
Keytruda belongs to a group of drugs called programmed death receptor-1 (PD-1) inhibitors. It’s also a type of immunotherapy. This means that it helps your immune system attack cancer cells.
Keytruda works by inhibiting (blocking) the activity of an immune system protein called PD-L1. It’s also known as a checkpoint protein.
This checkpoint protein attaches to PD-1 receptors (attachment sites). PD-1 receptors are found on cancer cells and healthy cells.
When PD-L1 attaches to PD-1 receptors, this signals certain immune system cells called T cells to stop attacking “invaders.” (Cancer cells are an example of cells that your body sees as invaders.) The action of PD-1 receptors allows cancer cells in your body to continue to grow without being attacked.
Some cancer cells have higher levels of PD-1. The extra PD-1 receptors help the cancer cells survive without being attacked by your immune system’s T cells.
Keytruda attaches to PD-1 receptors so that PD-L1 proteins cannot attach to them. By blocking the action of PD-L1, Keytruda lets your T cells continue attacking cancer cells. This boost in immune system function is meant to prevent your cancer from growing and spreading.
It depends. The timing of when Keytruda starts to work is different for each person and may depend on the condition you’re using Keytruda to treat.
How long does Keytruda stay in your system after stopping treatment?
Keytruda stays in your system for up to 4 months after your last dose.
Keytruda has a half-life of 22 days. This means it takes 22 days for your body to clear half a dose of Keytruda.
Due to the long-acting effects of Keytruda, there are certain precautions to keep in mind after treatment ends. If you can become pregnant, it’s recommended to use birth control for 4 months after your last dose. It’s also recommended to avoid breastfeeding for 4 months after your last dose.
If you have questions about what to expect after stopping Keytruda, talk with your doctor or pharmacist.
Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.
