How it is administered

Pembrolizumab is given as an intravenous (IV) infusion. This means it is administered directly into a vein, usually in your arm, over a period of about 30 minutes. The medication is available in vials containing 100 mg of pembrolizumab in 4 mL of solution. Your healthcare provider will prepare and give the infusion in a clinic or hospital setting. The typical dosing schedule is either every 3 weeks (200 mg) or every 6 weeks (400 mg), depending on your specific treatment plan and cancer type.

How it works

Pembrolizumab is a type of immunotherapy known as a PD-1 (programmed death receptor-1) blocking antibody. In some cancers, tumor cells use the PD-1 pathway to hide from the immune system. Pembrolizumab works by blocking the PD-1 receptor on T cells (a type of immune cell), preventing it from interacting with its ligands (PD-L1 and PD-L2) that are often found on tumor cells. By blocking this interaction, pembrolizumab helps restore the immune system’s ability to recognize and attack cancer cells.

For blood cancers, such as certain types of lymphoma, this can help the body’s own immune system fight the cancer more effectively. Pembrolizumab does not directly kill cancer cells, but instead boosts your immune response against them. This approach can lead to longer-lasting cancer control in some patients.

Who Should take it

Pembrolizumab is approved for use in several types of cancer, including certain blood cancers. For blood cancers, it is specifically indicated for:

• Adults with relapsed or refractory classical Hodgkin lymphoma (cHL)
• Pediatric patients with refractory cHL, or cHL that has relapsed after two or more lines of therapy
• Adults and pediatric patients with refractory primary mediastinal large B-cell lymphoma (PMBCL), or who have relapsed after two or more prior lines of therapy

While pembrolizumab is not specifically approved for Anaplastic Large Cell Lymphoma (ALCL), it may be considered in certain cases if other treatments are not suitable, but this would be at the discretion of your cancer care team. Always discuss your specific diagnosis and treatment options with your healthcare provider.

Who should not take it

There are no absolute contraindications listed for pembrolizumab, but it should be used with caution in certain situations. Patients who have had severe allergic reactions to pembrolizumab or any of its ingredients should not receive it.

Caution is also advised in patients with active autoimmune diseases, those who have had organ transplants, or those who are on immunosuppressive medications, as pembrolizumab can increase the risk of immune-related side effects. Pregnant women should avoid pembrolizumab, as it can harm an unborn baby. If you have a history of severe immune-mediated reactions or certain other medical conditions, your doctor will carefully weigh the risks and benefits before starting treatment.

Commonly used with

Pembrolizumab may be used alone (monotherapy) or in combination with other cancer treatments, depending on the type of cancer. For some blood cancers, it is typically used as a single agent, especially in relapsed or refractory cases. In other cancers, it may be combined with chemotherapy or targeted therapies. Your doctor will determine the best approach for your specific situation.

Commonly tested with

Pembrolizumab has been tested in combination with various other medications in clinical trials, including:

• Chemotherapy agents (such as platinum-based drugs)
• Other immunotherapies
• Targeted therapies (such as lenvatinib or axitinib in solid tumors)

For blood cancers, it is most often studied as a single agent, but research is ongoing to explore its use in combination with other drugs. Your treatment team will discuss the most current and effective options for your diagnosis.