keytruda FAQ

Your health care provider will regularly check how well Keytruda is working for your cancer through looking at results of tests such as blood tests and CT scans or MRI scans. You may notice improvements within a few weeks to months after starting Keytruda. The complete therapeutic effect can take longer, depending on individual factors and disease progression.

Your cancer doctor (oncologist) will arrange for you to receive Keytruda in a health care setting, such as a hospital or infusion center. If you need support paying for Keytruda, the drugmaker may be able to help you. Check out their Merck Financial Support website at www.keytruda.com/financial-support/ to learn more about their patient assistance program or to ask your questions about insurance coverage and out-of-pocket costs. You can also contact the drugmaker at 855-398-7832.

Keytruda may be used to treat certain types of these lung cancers:

Keytruda can cause severe side effects including skin reactions, diarrhea, and high blood sugar levels. Contact your health care provider right away if you notice any new rash or existing rash that is getting worse; reddening of the skin; fever; blistering of the lips, eyes, or mouth; blisters on the skin; skin peeling; or dry skin. They will decide whether you should stop taking Keytruda. They may also recommend creams or antihistamines to help with your rash and itchiness. Skin reactions are a common side effect of Keytruda and can happen at any time after you start taking it and even after you stop. You may also be given a corticosteroid to treat your rash. Notify your health care provider as soon as diarrhea starts, and start taking your diarrhea medicine. Drink more fluids to avoid losing too much of your body water (dehydration). Mild to moderate diarrhea can happen any time after you start taking Keytruda. Your health care provider may treat you with corticosteroids if your diarrhea is mild or moderate. If you have severe diarrhea, you may receive another immunosuppressive treatment given to you as an intravenous infusion. Your health care provider will tell you if you need to monitor your fasting blood sugar levels (blood sugar after an overnight fast) while you are taking Keytruda. Contact your health care provider if you notice your blood sugar rising or start having symptoms like feeling more thirsty than usual, needing to pee more often or in greater amounts, or have blurred vision or headaches. Your health care provider will have you get lab tests regularly and decide how to best manage your blood sugar levels. If you’re receiving Keytruda alongside platinum-based chemotherapy, your health care provider will typically recommend taking certain medications before your infusion to help prevent common side effects like nausea and vomiting, which are usually caused by the chemotherapy. It’s important to follow their instructions carefully. In addition to taking prescribed medications, you can ask your health care provider for additional strategies to manage or prevent side effects. For example, eating bland foods and having several small meals throughout the day, avoiding greasy foods, and drinking only small amounts of clear liquids can help manage nausea and vomiting. If you have certain side effects while you take Keytruda, your health care provider may need to change how often you get infusions, pause your infusions, or even stop your medicine altogether. This will depend on how severe the side effect is and what type of treatment it requires.

Some cancer cells have what are called checkpoint proteins known as PD-L1 on their cell surface. The immune cells in our bodies also have proteins on their surface. When these proteins bind to each other, the T cells in our body get turned “off,” which stops them from killing cancer cells. Keytruda acts on proteins on the T cell called PD-1 and prevents these proteins from binding to PD-L1 proteins on the tumor cell. This turns the T cell back “on” and allows it to do its job of attacking and killing the tumor cell.

Keytruda remains in the body for several months after the last dose. Even after stopping Keytruda, immune-related side effects may continue. Regular follow-up is essential to manage any lingering side effects and ensure a smooth transition off the treatment.

Both Keytruda and Keytruda Qlex contain pembrolizumab, but Keytruda is given as an IV infusion over 30 minutes while Keytruda Qlex is given as an injection under the skin (subcutaneous) over 1 minute. Both products are given by a health care professional. Doses are usually given every three or six weeks. Your health care provider will decide the dose and schedule that is right for you. They may pause or stop your treatment if your cancer gets worse (progresses) or if you have certain side effects.

Depending on the type of cancer you have and your body’s response to Keytruda, your doctor will tell you how many doses of Keytruda you’ll need. The long-term effects of Keytruda aren’t yet known. In studies, treatment length was limited to a maximum of 3 years. Your doctor may have you stop treatment early if your cancer worsens or if you have bothersome or severe side effects of Keytruda.

Keytruda’s mechanism of action (how it works) is to promote the activity of your immune system in order to stop cancer cells from growing. The drug blocks a protein called programmed death receptor-1 (PD-1) from interacting with another protein called programmed death ligand-1 (PD-L1). This helps to activate your immune system so that it can detect cancer cells and stop them from growing and spreading. Your doctor will monitor your treatment progress with imaging tests. If these tests show that the cancer cells have stopped growing or that the tumor size has shrunk, this is a sign that Keytruda treatment is working. Your doctor will also order blood tests to see how active your immune system is. Side effects like inflammation can sometimes show that Keytruda is working. However, not having certain side effects doesn't necessarily mean the drug isn't working.

Keytruda is a biologic medication that contains the active ingredient pembrolizumab. A biologic is made from parts of living organisms. Currently, Keytruda is available only as a brand-name drug. It isn’t available in a biosimilar form. Biosimilars are like generic drugs. But unlike generics, which are made for nonbiologic drugs, biosimilars are made for biologic drugs. If you have a certain type of advanced cancer, your doctor may prescribe Keytruda. It’s prescribed for:

You’ll receive Keytruda at your doctor’s office or an infusion clinic. If you miss an appointment for your dose, call the office or clinic to reschedule your appointment. Missing doses of Keytruda may decrease your body’s response to the drug.

Your doctor may have you stop Keytruda treatment early if: your cancer isn’t responding well to Keytruda, or you’re having bothersome or severe side effects from the drug But, even if your cancer remains stable and you’re tolerating Keytruda’s side effects, your doctor may have you stop treatment after a certain amount of time. This is because the long-term effects of Keytruda aren’t known. In studies, the length of Keytruda treatment was limited to about 2 to 3 years. But this depended on the type of cancer being treated. Talk with your doctor to find out how long you might need to take Keytruda.

Keytruda’s mechanism of action (how it works) is to promote the activity of your immune system in order to stop cancer cells from growing. The drug blocks a protein called programmed death receptor-1 (PD-1) from interacting with another protein called programmed death ligand-1 (PD-L1). This helps activate your immune system so that it can detect cancer cells and stop them from growing and spreading. Your doctor will monitor your treatment progress with imaging tests. If these tests show that the cancer cells have stopped growing or that the tumor size has shrunk, this is a sign that Keytruda treatment is working. Your doctor will also order blood tests to see how active your immune system is. Side effects like inflammation can sometimes show that Keytruda is working. However, not having certain side effects doesn’t necessarily mean the drug isn’t working.

Currently, Keytruda isn’t used to treat ovarian cancer. Some studies have shown that Keytruda may be beneficial for a certain type of ovarian cancer. This was seen when Keytruda was used either alone or together with other cancer drugs. But more studies are needed to confirm Keytruda’s effectiveness and safety in treating ovarian cancer. As described in the “What is Keytruda used for?” section, Keytruda does treat solid tumors with a certain gene mutation that cannot be removed by surgery or are spreading. This could include certain types of brain cancer. For this condition, the drug can be given to adults and children ages 6 months and older. But Keytruda isn’t recommended for children ages 6 months and older with brain cancer or spinal cord cancer that has a certain gene mutation. A recent study showed that Keytruda isn’t beneficial for a type of advanced brain cancer called high-grade glioma. Another study showed that recurring glioblastoma (another form of brain cancer) isn’t improved with Keytruda treatment, given either alone or together with another cancer drug. If you’d like to know more about treatment options for ovarian cancer or brain cancer, talk with your doctor.

No, Keytruda isn’t a chemotherapy drug. It’s an immunotherapy drug. Chemotherapy is a type of cancer treatment that kills cancer cells or stops them from multiplying (making more cells). Immunotherapy, on the other hand, works with your immune system to help your body fight off cancer cells. If you’d like to know more about the difference between chemotherapy and immunotherapy, talk with your doctor.

You’ll receive Keytruda as an injection into your vein. So how well your body absorbs the drug doesn’t depend on whether you receive it with a full or empty stomach. Talk with your doctor if you have questions about eating around the times you receive Keytruda doses.

No, Keytruda isn’t currently used for prostate cancer or pancreatic cancer. One study showed that Keytruda may be effective and safe for a specific type of prostate cancer called programmed death ligand 1 (PD-L1)-positive, metastatic castration-resistant prostate cancer. (PD-L1 is a type of protein. With metastatic prostate cancer, the cancer has spread from the prostate to other parts of the body. And with castration-resistant prostate cancer, the cancer doesn’t improve with treatment that lowers certain hormone levels.) But more studies are still needed to look at treating prostate cancer with Keytruda. For pancreatic cancer, recent studies have looked at using immunotherapy as treatment. (And keep in mind that Keytruda is an immunotherapy drug.) Researchers are currently studying a drug combination that includes pembrolizumab (the active drug in Keytruda) for advanced pancreatic cancer. Talk with your doctor if you’re interested in treatment options for prostate cancer or pancreatic cancer.

Every person may have a different response to Keytruda. Keytruda may help slow down the growth of cancer. The drug's success rate can vary depending on: the type of cancer that’s being treated any other drugs you may be taking to treat cancer In studies of Keytruda, researchers reported how long people lived and how long their cancer remained stable after starting Keytruda. If you’d like to know about these study results and the success rate of Keytruda for your type of cancer, talk with your doctor.

Keytruda can start working right away to promote your immune system’s activity. (This is how the drug works to treat cancer.) But it’s not known how long your immune system’s activity needs to be stimulated in order for the drug to treat your cancer. How long Keytruda takes to work may also depend on any other cancer medications you’re taking. Every few weeks or months, your doctor will assess how well your cancer is responding to Keytruda.