Keytruda (Pembrolizumab) - Intravenous

What Is Keytruda?

Keytruda (pembrolizumab) is an immunotherapy infusion (given through the veins) used to treat multiple types of cancer. It belongs to a class of medication called monoclonal antibodies, which is a type of immunotherapy.

As an immunotherapy, Keytruda targets cancer cells by blocking the PD-1 pathway. PD-1 is a specific protein receptor found on cells that keeps the immune system from attacking cells in the body. While this is usually a good thing, cancer cells in the body can use the PD-1 pathway to hide from these immune attacks. By blocking PD-1, Keytruda allows the body's immune system to recognize and attack cancer cells.

If you are undergoing therapy with Keytruda, you will need to receive it intravenously (in the veins) in a healthcare setting. A healthcare provider will administer it to you.

What Is Keytruda Used For?

Keytruda is used to treat different types of cancer. These include:

• Melanoma
• Non-small cell lung cancer
• Squamous cell cancer of the head and neck
• Classical Hodgkin lymphoma
• Primary mediastinal large B cell lymphoma
• Urothelial carcinoma
• Microsatellite instability-high or mismatch repair deficient cancer
• Gastric cancer
• Esophageal cancer
• Cervical cancer
• Merkel cell carcinoma
• Hepatocellular carcinoma
• Renal cell carcinoma
• Endometrial carcinoma
• Tumor-mutational burden high carcinoma
• Cutaneous squamous cell carcinoma
• Triple-negative breast cancer

How to Take Keytruda

Keytruda is given through the veins (intravenous infusion) every three to six weeks for as long as your oncologist recommends. It will usually take 30 minutes for each infusion.

The medication will be administered in a hospital or medical facility under the supervision of healthcare providers. Keep up with your appointments, and don't hesitate to discuss any concerns with the healthcare team.

Storage

Since a healthcare provider will administer Keytruda to you in a medical facility, there is no need to worry about storing the medication yourself.

What Are the Side Effects of Keytruda?

Side effects from Keytruda may be due to the effects of the medication itself or the ways it can cause a reaction from the immune system.

This is not a complete list of side effects and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your healthcare provider. You may report side effects to the Food and Drug Administration (FDA) at fda.gov/medwatch or 1-800-FDA-1088.

Common Side Effects

The most common side effects from Keytruda include:

• Fatigue
• Muscle pain
• Bone pain
• Decreased appetite
• Itching of the skin
• Diarrhea
• Nausea
• Rash
• Fever
• Cough
• Shortness of breath
• Constipation
• Abdominal pain

Side effects can occur at any time during treatment and after. Tell your cancer care team about any side effects, even mild ones. Oftentimes, side effects can be managed.

Severe Side Effects

Sometimes, the immune system may react to Keytruda by attacking healthy cells (immune-mediated reaction). This causes inflammation in this area. Some of these reactions may be severe. These may include:

• Pneumonitis (inflammation of the lungs): Symptoms may include chest pain, cough, and shortness of breath. 
• Colitis (inflammation of the colon): Symptoms may include diarrhea and abdominal pain.
• Hepatitis (inflammation of the liver): No symptoms may be present, but elevation in blood liver tests may be found.
• Endocrinopathies (inflammation of glands such as the pituitary gland, thyroid, or adrenal glands): Symptoms may include headache, vision changes, and fatigue.
• Nephritis (inflammation of the kidneys): Symptoms may include pelvic pain, difficulty urinating, frequent urination, and blood in the urine. 
• Skin inflammation: Symptoms may include itching or rash.

Depending on the severity of immunotherapy-related side effects, your oncologist may temporarily stop your treatment or discontinue it altogether.

Call your cancer (oncology) treatment team immediately if you experience severe side effects. Call 911 or go to the nearest emergency room if you feel your symptoms are life-threatening.

Dosage: How Much Keytruda Should I Take?

A healthcare provider will administer Keytruda intravenously (in the vein) at your scheduled appointments. The dosing schedule for Keytruda is either every three or six weeks. Your oncologist will determine how long you need to undergo this treatment. Each infusion takes about 30 minutes.

Modifications

It may be necessary to hold or stop altogether if severe side effects or immune reactions occur. Keytruda should also not be used while pregnant or breastfeeding.

Missed Dose

If you keep up with your regular appointments, you should not worry about missing any doses of Keytruda. Talk to your healthcare team if something comes up that might interfere with your treatment schedule.

Overdose: What Happens If I Take Too Much Keytruda?

Keytruda is only available by infusion at a hospital or cancer (oncology) treatment clinic and not taken at home. It’s unlikely that an overdose of Keytruda would occur.

Precautions

What Are Reasons I Shouldn’t Take Keytruda?

Keytruda may not be the right treatment for you if you are pregnant, as it can harm the fetus. If you can get pregnant, use effective birth control (contraception) while undergoing treatment and for four months after your last dose.

You may also be advised not to breastfeed while taking Keytruda and for four months after the last dose, as it can affect breast milk.

What Other Medications Interact With Keytruda?

There are no known serious interactions between Keytruda and other medications.

What Medications Are Similar?

There are other immunotherapies similar to Keytruda in the way they work to treat cancer.

These include:

• Opdivo (nivolumab)
• Tecentriq (atezolizumab)
• Imfinzi (durvalumab)

Like Keytruda, these drugs are also given intravenously to treat a range of cancer types.

How Can I Stay Healthy While Taking Keytruda?

Going through cancer treatment can be overwhelming. Taking good care of your mental and physical well-being is important.

Try eating a healthy, well-balanced diet with plenty of protein and calories that includes:

• Lots of fruits and vegetables
• Whole grains
• Cereals
• Some meat and milk products

The side effects of cancer medications can sometimes make eating difficult. You may be experiencing some nausea or appetite loss. This is normal. Talk to your healthcare team about how to best manage these side effects. A registered dietitian can also help you optimize your diet for your needs.

The following are a few other general tips for staying healthy during treatment:

• Drink plenty of water (8 to 12 cups) to stay hydrated, especially on days you feel you can't eat.
• Get enough sleep.
• Participate in exercise if you're feeling up to it.
• Join a support group.

Remember that you're not alone during this time. Your healthcare team is there to guide you through your treatment plan. If you experience side effects from Keytruda, contact your cancer (oncology) treatment team immediately, especially if they are severe.