Common brand names

• Keytruda

How it is administered

Pembrolizumab is given as an intravenous (IV) infusion. This means it is delivered directly into your vein through a drip, usually over 30 minutes. It is available as a clear to slightly opalescent, colorless to slightly yellow solution in vials containing 100 mg in 4 mL.

The typical dosing for adults is 200 mg every 3 weeks or 400 mg every 6 weeks, depending on your cancer type and treatment plan. Your healthcare provider will determine the exact schedule and dose for you.

How it works

Pembrolizumab is a type of immunotherapy known as a PD-1 (programmed death receptor-1) blocking antibody. In many cancers, including some blood cancers, cancer cells can hide from the immune system by activating a pathway called PD-1. This pathway normally helps keep the immune system from attacking healthy cells, but cancer cells can exploit it to avoid being destroyed.

Pembrolizumab works by blocking the PD-1 receptor on immune cells called T cells. By blocking this pathway, pembrolizumab helps your immune system recognize and attack cancer cells more effectively. This can slow down or stop the growth of cancer and, in some cases, shrink tumors. The treatment is used for several types of cancers, including certain blood cancers such as classical Hodgkin lymphoma and primary mediastinal large B-cell lymphoma.

Who should take it

Pembrolizumab is used to treat adults with several types of cancer, including certain blood cancers. For blood cancers, it is specifically approved for:

• Adults with relapsed or refractory classical Hodgkin lymphoma (cHL).
• Adults with refractory primary mediastinal large B-cell lymphoma (PMBCL), or those who have relapsed after two or more prior lines of therapy.

It may also be used for other cancers, such as melanoma, lung cancer, and others, depending on your specific diagnosis and previous treatments. Your doctor will decide if pembrolizumab is appropriate for you based on your cancer type, stage, and previous treatments.

Who should not take it

There are no absolute contraindications listed for pembrolizumab, but it should be used with caution in certain situations:

• If you have a history of severe immune-mediated reactions to pembrolizumab or similar drugs.
• If you have active autoimmune diseases or require immunosuppressive medications, pembrolizumab may not be suitable or may require careful monitoring.
• Pregnant women should not take pembrolizumab, as it can cause harm to an unborn baby. Women of childbearing potential should use effective contraception during treatment and for 4 months after the last dose.

Always discuss your full medical history with your doctor before starting pembrolizumab.

Commonly used with

Pembrolizumab may be used alone or in combination with other cancer treatments, depending on your specific diagnosis. In blood cancers, it is often used as a single agent, especially for relapsed or refractory cases. In solid tumors, it may be combined with chemotherapy or other targeted therapies.

Your doctor will decide the best combination based on your cancer type and previous treatments.

Commonly tested with

Pembrolizumab has been tested in combination with other cancer therapies, such as chemotherapy agents (e.g., platinum-based drugs), targeted therapies (like lenvatinib or axitinib), and other immunotherapies. In blood cancers, clinical trials have explored its use after other standard treatments have failed, or in combination with other agents in research settings.

If you are participating in a clinical trial, your doctor will explain the specific combination and monitoring involved.