Keytruda (pembrolizumab)

What is Keytruda?

Keytruda is a brand-name prescription drug. It’s FDA-approved to treat several forms of advanced cancers, including certain types of:

• skin cancer
• lung cancer
• head and neck cancer
• lymphoma
• bladder cancer
• stomach cancer
• esophageal cancer
• cervical cancer
• liver cancer
• kidney cancer
• endometrial cancer
• breast cancer
• other solid tumors

Keytruda is approved for all of these uses in adults. And for some conditions, Keytruda is approved for use in children. These conditions include certain forms of:

• lymphoma
• solid tumors
• skin cancer

Keytruda contains the drug pembrolizumab. It belongs to a class of drugs called PD-1 inhibitors. Keytruda is an immunotherapy drug, which means it tells certain parts of your immune system to attack cancer cells.

Keytruda is given as an intravenous (IV) infusion by healthcare providers. (With an IV infusion, the drug is injected into your vein over a period of time.) Keytruda is approved for use in combination with other drugs when treating certain types of cancer. But for some types of cancer, Keytruda is approved for use on its own.

Effectiveness

Keytruda has been found effective in treating each type of cancer listed above. To read about the effectiveness of Keytruda for these conditions, see the section “Keytruda uses” below.

FDA approval

In 2014, Keytruda was first approved by the Food and Drug Administration (FDA) to treat several types of cancer. Since its initial approval, Keytruda has been approved for new and expanded uses.

In 2019 alone, the FDA approved the drug for eight new or expanded uses. These uses included certain forms of head and neck cancer and esophageal cancer.

Keytruda uses

The Food and Drug Administration (FDA) approves prescription drugs such as Keytruda to treat certain conditions. Keytruda may also be used off-label for other conditions. Off-label use is when a drug that’s approved to treat one condition is used to treat a different condition.

Keytruda for non-small cell lung cancer

Keytruda is FDA-approved to treat several types of non-small cell lung cancer (NSCLC). This type of lung cancer is the most common form of lung cancer.

Lung cancer can develop from different types of cells in your lungs. If NSCLC comes from squamous cells, it’s called squamous NSCLC. But if NSCLC comes from cells other than squamous cells, it’s called non-squamous NSCLC. (Squamous cells are thin, flat cells. They’re found in different areas of your body, including on the surface of airways inside your lungs.)

For the following types of NSCLC, Keytruda can be used as a first-line treatment,* in combination with certain chemotherapy drugs (traditional drugs used to treat cancer):

• metastatic** non-squamous NSCLC that doesn’t have certain gene mutations (abnormal changes)
• metastatic squamous NSCLC

* With first-line treatment, Keytruda is the first drug used for the cancer.
** With metastatic NSCLC, the cancer has spread from the lungs to other parts of the body. Metastatic lung cancer is also called stage four (IV) lung cancer.

Keytruda is also approved for use on its own as a first-line treatment for certain types of NSCLC. For this use, the NSCLC must have high levels of an immune system protein called PD-L1. But it must not have certain gene mutations. Keytruda can be used in this way to treat either:

• stage three (III)* NSCLC in people who can’t receive either surgical treatment or a combination of chemotherapy and radiation therapy, or
• metastatic NSCLC

* With stage III NSCLC, the cancer has spread to areas near your lungs, but it hasn’t spread to other body parts yet.

In addition, Keytruda is also approved for use on its own to treat metastatic NSCLC in people:

• whose tumors have high levels of the PD-L1 protein, and
• whose cancer has gotten worse while taking or after taking certain chemotherapy drugs

However, for this use, if people have certain gene mutations, their cancer must have gotten worse with other cancer drugs approved to treat cancers with those mutations before Keytruda can be used.

Keytruda’s effectiveness for NSCLC

In clinical studies, Keytruda has been found to be effective in treating different forms of NSCLC.

In a clinical study, Keytruda (used with certain chemotherapy drugs) was effective as first-line treatment for metastatic, non-squamous NSCLC that had not been treated in the past. People taking Keytruda with certain chemotherapy drugs had better overall survival* and progression-free survival** than people taking a placebo with certain chemotherapy drugs. (A placebo is a treatment that contains no active drug.)

In this study, half of the people taking Keytruda with chemotherapy had a progression-free survival of at least 8.8 months. In comparison, half of the people taking a placebo with chemotherapy had a progression-free survival of at least 4.9 months.

In another clinical study, Keytruda, used with certain chemotherapy drugs, was also effective as first-line treatment for metastatic, squamous NSCLC that had not been treated in the past.

People taking Keytruda with certain chemotherapy drugs had better progression-free survival and response rates to treatment than did people taking a placebo with certain chemotherapy drugs.

In the study, half of the people taking Keytruda with chemotherapy had a progression-free survival of at least 6.4 months. In comparison, half of the people taking a placebo with chemotherapy had a progression-free survival of at least 4.8 months.

For more information on Keytruda’s effectiveness in people with NSCLC, please see the drug’s prescribing information.

* Overall survival describes the length of time people lived after they joined the study.
** Progression-free survival describes the length of time that people lived with their disease without the disease getting worse.

Keytruda for melanoma

Keytruda is FDA-approved to treat a certain type of skin cancer called melanoma. With melanoma, cancer develops in skin cells called melanocytes. These cells make melanin, which is the pigment that gives your skin its color.

Keytruda is approved to treat melanoma that can’t be surgically removed or that’s metastatic. (With metastatic melanoma, the cancer has spread from your skin to other parts of your body.)

In addition, Keytruda is approved as adjuvant therapy to treat melanoma that has spread to lymph nodes. (Adjuvant therapy is treatment that’s given after surgery or medication to prevent someone’s cancer from coming back.) For this use, Keytruda is given to people whose melanoma has been completely removed with surgery. The drug is used to prevent the skin cancer from coming back.

Keytruda is also approved to treat other types of skin cancer called Merkel cell carcinoma (MCC) and cutaneous squamous cell carcinoma (cSCC). For more information about these uses, see the section below called “Keytruda for skin cancer.”

Keytruda’s effectiveness for melanoma

In clinical studies, Keytruda was effective in treating different types of melanoma.

For example, in one clinical study of people with melanoma, those taking Keytruda had better overall survival* and progression-free survival** compared with people taking a cancer drug called ipilimumab (Yervoy).

In this study, half of the people taking Keytruda had a progression-free survival of up to 5.5 months or more. In comparison, half of the people taking ipilimumab had a progression-free survival of 2.8 months or more.

For more information on Keytruda’s effectiveness in people with melanoma, please see the drug’s prescribing information.

* Overall survival describes the length of time people lived after they joined the study.
** Progression-free survival describes the length of time that people lived with their disease without the disease getting worse.

Keytruda for microsatellite instability-high cancer and tumor mutational burden-high cancer

Keytruda is FDA-approved to treat solid tumors with certain gene mutations (abnormal changes). Specifically, Keytruda can be used to treat solid tumors with either the microsatellite instability-high (MSI-H) mutation or the mismatch repair deficient (dMMR) mutation.*

MSI-H and dMMR mutations prevent genetic material in your body from correcting its own mistakes. These mistakes are typically made when the genes are copied to make new proteins or cells.

Keytruda is approved for this use in adults and children whose cancer has all of the following characteristics:

• It worsened after using other treatments.
• It has no other safe or effective treatment options available.
• It either can’t be surgically removed or has spread to other parts of the body (called metastatic cancer).

Keytruda is also approved for use in people who have colorectal cancer, a type of solid tumor, with either MSI-H or dMMR mutation. But their cancer is either unable to be surgically removed or it’s metastatic.

Additionally, Keytruda is used to treat solid tumors that are considered tumor mutational burden-high (TMB-H).* This cancer has a higher number of certain gene mutations.

* For these uses, Keytruda received accelerated approval from the FDA. Accelerated approval is based on information from early clinical trials. The FDA’s decision for full approval will be made after additional clinical trials are completed.

Keytruda’s effectiveness for MSI-H cancer

In several studies, Keytruda was effective in treating different types of MSI-H cancers. For example, in the studies:

• 32.2% of people taking Keytruda had their cancer partially go away
• 7.4% of people taking Keytruda had their cancer completely go away
• of people whose cancer either partially or completely went away, 78% kept these results for at least 6 months

Keytruda’s effectiveness for TMB-H cancer

In a clinical study, Keytruda was effective in treating TMB-H cancer. For details on how the drug performed in this study, see the drug’s prescribing information.

Keytruda for bladder cancer

Keytruda is FDA-approved to treat a specific type of bladder cancer called urothelial cancer. This form of cancer affects your urothelial cells, which line the inside of your bladder.

Keytruda is approved to treat urothelial cancer that is either locally advanced (has spread to nearby areas) or metastatic (has spread to other parts of the body) and either:

• can’t be treated with chemotherapy that’s made with platinum, or
• worsened during or after certain treatment with chemotherapy that’s made with platinum

In addition, Keytruda is also approved to treat a certain type of bladder cancer that forms on the lining inside your bladder and that doesn’t respond to certain treatments. For this use, Keytruda is given to people who’ve chosen not to have surgery or who aren’t able to have surgery for their cancer.

Keytruda’s effectiveness for bladder cancer

In studies, Keytruda was effective in people with certain types of bladder cancer. In one clinical study of people with urothelial cancer that couldn’t be treated by certain chemotherapy drugs:

• 20% of people who took Keytruda had their cancer partially go away
• 10% of people who took Keytruda had their cancer completely go away

For more information on Keytruda’s effectiveness in people with bladder cancer, please see the drug’s prescribing information.

Keytruda for liver cancer

Keytruda is FDA-approved to treat hepatocellular carcinoma.* This type of cancer is the most common form of liver cancer.

Keytruda is approved to treat hepatocellular carcinoma in people who’ve taken the cancer drug sorafenib (Nexavar) in the past for this condition.

* For this use, Keytruda received accelerated approval from the FDA. Accelerated approval is based on information from early clinical trials. The FDA’s decision for full approval will be made after additional clinical trials are completed.

Keytruda’s effectiveness for liver cancer

In a clinical study, Keytruda was effective in treating liver cancer in people whose cancer either worsened or came back after treatment with sorafenib (Nexavar). And Keytruda was effective for this use in people who couldn’t tolerate Nexavar’s side effects.

In the study:

• 16% of people taking Keytruda had their cancer partially go away
• 1% of people taking Keytruda had their cancer completely go away
• of people whose cancer either partially or completely went away, 89% kept these results for at least 6 months
• of people whose cancer either partially or completely went away, 56% kept these results for at least 12 months

Keytruda for head and neck cancer

Keytruda is FDA-approved to treat head and neck squamous cell carcinoma (HNSCC). With HNSCC, cancer develops in the skin or mucous membranes (moist surface tissues) of your mouth, throat, or nose. The cancer comes from squamous cells, which are thin, flat cells. These cells make up the lining of the mucous membranes in your head and neck.

For HNSCC, Keytruda can be given as first-line treatment. (With first-line treatment, Keytruda is the first drug given to treat the cancer.) For this use, Keytruda can be given in combination with certain other cancer drugs for HNSCC that’s either:

• metastatic (has spread to other parts of the body), or
• both recurrent (has returned after past treatment) and unable to be surgically removed

Keytruda can be used on its own as a first-line treatment for HNSCC that has the immune system protein called PD-L1. For this use, Keytruda is used to treat cancer that’s either metastatic or both recurrent and unable to be surgically removed.

In addition, Keytruda is used alone to treat either recurrent or metastatic HNSCC that has gotten worse during or after certain past treatments.

Keytruda’s effectiveness for head and neck cancer

In clinical studies, Keytruda was effective in treating HNSCC.

In one study of people with metastatic or recurrent HNSCC, those taking Keytruda with certain chemotherapy drugs had better overall survival than people who didn’t take Keytruda. (Overall survival describes the length of time people lived after they joined the study.)

In this study, half of the people taking Keytruda with chemotherapy (traditional drugs used to treat cancer) had an overall survival of at least 13.0 months. In comparison, half of the people taking a placebo (no active drug) with chemotherapy had an overall survival of at least 10.7 months.

For more information on Keytruda’s effectiveness in people with HNSCC, please see the drug’s prescribing information.

Keytruda for cervical cancer

Keytruda is FDA-approved to treat cervical cancer. This form of cancer develops in the cervix, which separates a woman’s uterus and vagina.

Keytruda is used to treat cervical cancer that has high levels of the immune system protein called PD-L1.

It’s given in combination with chemotherapy, with or without bevacizumab (Avastin), to treat cancer that’s either:

• persistent (hasn’t responded to treatment)
• recurrent (has returned after past treatment)
• metastatic (has spread to other parts of the body)

Keytruda is used by itself to treat recurrent or metastatic cervical cancer that has worsened either during or after chemotherapy.

Keytruda’s effectiveness for cervical cancer

In one clinical study, Keytruda was effective in treating cervical cancer. In one study:

• 11.7% of people taking Keytruda had their cancer partially go away
• 2.6% of people taking Keytruda had their cancer completely go away
• of people whose cancer either partially or completely went away, 91% kept these results for at least 6 months

Keytruda for gastric cancer

Keytruda is FDA-approved to treat gastric cancer (stomach cancer). It’s also approved to treat cancer that’s found in your gastroesophageal junction (the area where your stomach meets your esophagus).

For these uses,* Keytruda is given to people whose cancer is both:

• recurrent (has returned after past treatment), and
• either locally advanced (has spread to nearby areas) or metastatic (has spread to other parts of the body)

Keytruda can be prescribed for people whose cancer has each of the following characteristics:

• it’s adenocarcinoma (a type of cancer that’s found in glandular cells that normally produce mucus)
• it has high levels of the immune system protein called PD-L1
• it has gotten worse during or after past treatment with two of more certain types of cancer drugs

Additionally, Keytruda is approved to treat gastric or gastroesophageal cancer that is HER2-positive, which means it has certain receptors (attachment sites).* And it must be either:

• locally advanced and not treatable with surgery, or
• metastatic

For this use, Keytruda is given together with:

• trastuzumab
• chemotherapy made with fluoropyrimidine
• chemotherapy made with platinum

In combination with these other drugs, Keytruda can be used as a first-line treatment (the first treatment used for the cancer).

* For these uses, Keytruda received accelerated approval from the FDA. Accelerated approval is based on information from early clinical trials. The FDA’s decision for full approval will be made after additional clinical trials are completed.

Keytruda’s effectiveness for gastric cancer

In one clinical study, Keytruda was effective in treating gastric cancer. In the study:

• 11.9% of people taking Keytruda had their cancer partially go away
• 1.4% of people taking Keytruda had their cancer completely go away
• of people whose cancer either partially or completely went away, 58% kept these results for at least 6 months
• of people whose cancer either partially or completely went away, 26% kept these results for at least 12 months

Keytruda for Hodgkin disease

Keytruda is FDA-approved to treat classical Hodgkin lymphoma (cHL). This type of lymphoma is a cancer that develops in your B cells. (B cells are a part of your immune system.) And it’s the most common form of Hodgkin lymphoma.

For this condition, Keytruda is given to adults with refractory or relapsed cHL. With refractory cHL, the cancer either doesn’t improve with treatment or doesn’t stay improved after treatment for very long. And with relapsed cancer, it comes back after being treated in the past.

Keytruda is also used in children to treat cHL that has relapsed after two or more past treatments.

Keytruda’s effectiveness for Hodgkin disease

In a clinical study, Keytruda was effective in treating cHL. In the study:

• 47% of people taking Keytruda had their cancer partially go away
• 22% of people taking Keytruda had their cancer completely go away
• of people whose cancer either partially or completely went away, half of them kept these results for at least 11.1 months

Keytruda for lymphoma

Keytruda is FDA-approved to treat primary mediastinal large B-cell lymphoma (PMBCL). This condition is a type of blood cancer. It develops in your mediastinum (the area in the middle of your chest). PMBCL affects your B cells, which are a type of white blood cell in your immune system.

Keytruda can be given to adults and children with PMBCL. The drug can treat PMBCL that either hasn’t gotten better with or has worsened after using two or more past cancer treatments.

For this use, Keytruda isn’t used in people who need urgent cytoreductive therapy. Doctors use this therapy to rapidly bring down the level of white blood cells, including B cells, in the body.

Keytruda’s effectiveness for lymphoma

In one clinical study, Keytruda was effective in treating PMBCL. In the study:

• 34% of people taking Keytruda had their cancer partially go away
• 11% of people taking Keytruda had their cancer completely go away

Keytruda for skin cancer

Keytruda is FDA-approved to treat skin cancers called Merkel cell carcinoma (MCC)* and cutaneous squamous cell carcinoma (cSCC).

Keytruda for Merkel cell carcinoma

For MCC, Keytruda can be given to adults and children.

MCC develops in certain skin cells called Merkel cells. These cells are involved with nerves in your skin. And they may also be involved with certain hormones in your body.

Keytruda is approved to treat MCC that’s both recurrent (has returned after past treatment) and either:

• locally advanced (has spread to nearby areas), or
• metastatic (has spread to other parts of the body)

In addition, Keytruda is also approved to treat another type of skin cancer called melanoma. For more information about this use, see the section “Keytruda for melanoma” above.

* For this use, Keytruda received accelerated approval from the FDA. Accelerated approval is based on information from early clinical trials. The FDA’s decision for full approval will be made after additional clinical trials are completed.

Keytruda’s effectiveness for Merkel cell carcinoma

In one study, Keytruda was effective in treating MCC in people who hadn’t had MCC treatment in the past. In the clinical study:

• 32% of people taking Keytruda had their cancer partially go away
• 24% of people taking Keytruda had their cancer completely go away
• of people whose cancer either partially or completely went away, 96% kept these results for at least 6 months
• of people whose cancer either partially or completely went away, 54% kept these results for at least 12 months

Keytruda for cutaneous squamous cell carcinoma

For cSCC, Keytruda can be given to adults.

This condition develops in certain skin cells called squamous cells. They’re flat cells located in the outer layer of the skin.

Keytruda is used for cSCC that’s either:

• metastatic (has spread to other parts of the body) or recurrent (has returned after past treatment), or
• locally advanced (has spread to nearby areas), but can’t be cured with surgery or radiation therapy

Keytruda’s effectiveness for cutaneous squamous cell carcinoma

Current treatment guidelines include Keytruda as a treatment option for cSCC.

In a clinical study, Keytruda was shown to be effective in treating cSCC. For details on how the drug performed in this study, see the drug’s prescribing information.

Keytruda for kidney cancer

Keytruda is FDA-approved to treat advanced renal cell carcinoma (kidney cancer). For this condition, it’s approved for use in combination with either axitinib (Inlyta) or lenvatinib (Lenvima).

Keytruda can be given as a first-line treatment to adults with advanced kidney cancer. (With first-line treatment, the drug is the first treatment used for the cancer.)

Keytruda’s effectiveness in kidney cancer

In one study, Keytruda was effective in treating kidney cancer when used in combination with axitinib (Inlyta). In the clinical study, people taking Keytruda with axitinib had better overall survival* and progression-free survival** compared with people taking a cancer drug called sunitinib (Sutent).

At 12 months of treatment, 90% of people taking Keytruda with axitinib were still alive. In comparison, 78% of people taking sunitinib without Keytruda were still alive at 12 months. Half of the people taking Keytruda with axitinib also had a progression-free survival of at least 15.1 months. In comparison, half of the people taking sunitinib had a progression-free survival of at least 11.0 months.

* Overall survival describes the length of time people lived after they joined the study.
** Progression-free survival describes the length of time that people lived with their disease without the disease getting worse.

Keytruda for esophageal cancer

Keytruda is FDA-approved to treat squamous cell esophageal cancer and gastroesophageal cancer in certain cases.

Esophageal cancer develops in squamous cells (thin, flat cells) found on the surface of your esophagus. (The esophagus is a tube that connects your throat to your stomach.) Gastroesophageal cancer forms in the area where your stomach meets your esophagus.

Keytruda treats these types of cancer that can’t be treated with surgery or a combination of chemotherapy and radiation. And the cancer must be either:

• locally advanced (has spread to nearby areas), or
• metastatic (has spread to other parts of the body)

Keytruda’s effectiveness for esophageal cancer

In clinical studies, Keytruda was effective in treating esophageal cancer. In one clinical study, people taking Keytruda had better overall survival compared with people taking chemotherapy (traditional drugs used to treat cancer). (Overall survival describes the length of time people lived after they joined the study.)

For example, half of the people taking Keytruda had an overall survival of at least 10.3 months. In comparison, half of the people taking chemotherapy had an overall survival of at least 6.7 months.

Keytruda for endometrial cancer

Keytruda is FDA-approved to treat advanced endometrial cancer. For this use, Keytruda is given in combination with another cancer drug called lenvatinib (Lenvima).

With endometrial cancer, the cancer develops in the lining (endometrium) of your uterus. Advanced endometrial cancer has spread out of your uterus and pelvis to other parts of your body.

Keytruda is approved to treat advanced endometrial cancer that doesn’t have certain gene mutations (abnormal changes). This drug is prescribed for people:

• who aren’t able to have either surgery or radiation therapy, and
• whose cancer worsened after past systemic treatments (therapy that affects your whole body)

Keytruda’s effectiveness for endometrial cancer

In studies, Keytruda, used in combination with lenvatinib, was effective in treating advanced endometrial cancer. In one clinical study:

• 25% of people taking Keytruda had their cancer partially go away
• 5% of people taking Keytruda had their cancer completely go away

Keytruda for breast cancer

Keytruda is FDA-approved to treat a type of breast cancer called triple-negative breast cancer. This type of cancer forms in the breast. And it lacks certain proteins and receptors (attachment sites).

Keytruda treats triple-negative breast cancer that:

• has a high risk of getting worse
• is in an early stage

For this use, Keytruda is given in combination with both chemotherapy and surgery. And it’s continued by itself after surgery has been done.

Keytruda is also used in combination with chemotherapy to treat triple-negative breast cancer that:

• is recurrent (has come back after past treatment) and can’t be cured with surgery or is metastatic (has spread to other parts of the body), and
• has the immune system protein called PD-L1

Keytruda’s effectiveness for breast cancer

Keytruda is recommended in current treatment guidelines as a treatment option for triple-negative breast cancer in certain situations.

In clinical studies Keytruda has been effective in treating this type of breast cancer. For details on how this drug performed in studies, see the drug’s prescribing information.

Off-label uses for Keytruda

In addition to the uses listed above, Keytruda may be used off-label for other purposes. Off-label drug use is when a drug that’s approved for one use is used for a different use that’s not approved.

Keytruda for pancreatic cancer

Keytruda isn’t FDA-approved to treat pancreatic cancer. But sometimes it’s used off-label for this purpose.

Current treatment guidelines list Keytruda as a second-choice treatment option for people with pancreatic cancer that has either:

• microsatellite instability-high (MSI-H) gene mutations,* or
• mismatch repair deficient (dMMR) genetic mutations

* Mutations are abnormal changes in a gene.

For this use, Keytruda is given to people who used treatments in the past for their pancreatic cancer. But their condition either didn’t improve with or worsened after these past treatments.

If you’d like to know more about using Keytruda to treat pancreatic cancer, talk with your doctor.

Keytruda for ovarian cancer

Keytruda isn’t FDA-approved to treat ovarian cancer. But sometimes it’s used off-label for this condition.

Current treatment guidelines list Keytruda as an option for people with ovarian cancer that has either:

• microsatellite instability-high (MSI-H) gene mutations,* or
• mismatch repair deficient (dMMR) genetic mutations

* Mutations are abnormal changes in a gene.

These guidelines also list Keytruda as a treatment for ovarian cancer that has numerous gene mutations and is called tumor mutational burden-high (TMB-H).

If you’d like to know more about using Keytruda to treat ovarian cancer, talk with your doctor.

Keytruda for brain cancer

Keytruda isn’t FDA-approved to treat brain cancer, including a fast-growing form of brain cancer called glioblastoma.

However, treatment guidelines recommend Keytruda as an option for people whose cancer has spread from other parts of their body to their brain. For example, this may include certain types of skin or lung cancer that has spread into their brain. (When cancer spreads from where it started to other parts of the body, it’s called metastatic cancer.)

In one clinical study, Keytruda was used by people with either melanoma or non-small cell lung cancer (NSCLC) who had brain metastasis. Of people with melanoma who had brain metastasis, 22% had their brain cancer either go away or shrink in size. Of people with NSCLC who had brain metastasis, 33% had the same result.

Studies are being done to see whether Keytruda can play a role in treating glioblastoma and other brain cancers.

If you’d like to know more about using Keytruda to treat cancer in your brain, talk with your doctor.

Keytruda for cholangiocarcinoma

Keytruda is not FDA-approved to treat cholangiocarcinoma, but it’s sometimes used off-label for this purpose. Cholangiocarcinoma is a form of cancer that’s related to liver cancer. It develops in your bile ducts, which are found in and around your liver.

Treatment guidelines recommend Keytruda as an option for people with cholangiocarcinoma who have certain gene mutations (abnormal changes).

If you’d like to know more about using Keytruda to treat cholangiocarcinoma, talk with your doctor.

Keytruda for multiple myeloma (not a typical off-label use)

Keytruda isn’t FDA-approved to treat multiple myeloma. In fact, the manufacturer of Keytruda reports that using this drug with other cancer drugs to treat multiple myeloma is related to an increased risk of death.

In 2017, the FDA alerted healthcare providers of this increased risk of death. And at that time, the FDA required researchers to stop clinical studies that were testing Keytruda for multiple myeloma treatment.

If you’d like to know more about treatment options for multiple myeloma, talk with your doctor.

Keytruda and children

Keytruda is FDA-approved for use in children with the following types of cancer:

• classical Hodgkin lymphoma (cHL)
• primary mediastinal large B-cell lymphoma (PMBCL)
• microsatellite instability-high cancer (MSI-H cancer)
• Merkel cell carcinoma (MCC)
• solid tumors with certain gene mutations (abnormal changes) called:
  • microsatellite instability-high (MSI-H)
  • mismatch repair deficient (dMMR)
  • tumor mutational burden-high (TMB-H)

To learn more about these types of cancer, see the descriptions above in this “Keytruda uses” section.

It’s important to note that Keytruda isn’t approved to treat certain cancers of the central nervous system in children. These include cancers of the brain or spinal cord that have MSI-H or TMB-H genetic mutations.

Keytruda generic

Keytruda is available only as a brand-name medication. It’s not currently available in generic form. A generic drug is an exact copy of the active drug in a brand-name medication.

Keytruda contains the active drug pembrolizumab.

Keytruda side effects

Keytruda can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking Keytruda. These lists do not include all possible side effects. And you may have side effects other than those listed below if you’re taking Keytruda in combination with other drugs.

For more information on the possible side effects of Keytruda, talk with your doctor or pharmacist. They can give you tips on how to deal with any side effects that may be bothersome.

Note: The Food and Drug Administration (FDA) tracks side effects of drugs they have approved. If you would like to report to the FDA a side effect you’ve had with Keytruda, you can do so through MedWatch.

More common side effects

The more common side effects of Keytruda can include:

• belly pain
• constipation
• cough
• diarrhea
• decreased appetite
• shortness of breath
• fatigue (lack of energy)
• fever
• rash or itchy skin
• bone or muscle pain
• nausea

Most of these side effects may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from Keytruda can occur. Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency.

Serious side effects and their symptoms can include the following:

• Colitis (inflammation in your colon) that’s caused by an immune system reaction. Symptoms can include:
  • bloating or cramping in your belly
  • diarrhea
  • fever
• Hepatitis (inflammation in your liver) or liver damage that’s caused by an immune system reaction. Signs and symptoms can include:
  • high levels of liver enzymes (certain types of proteins)
  • pain in the upper right area of your belly
  • itchy skin
  • jaundice (yellowing of your skin or the whites of your eyes)
  • nausea or vomiting
• Hormone disorders, including hypothyroidism (low thyroid hormone level), that are caused by an immune system reaction. Symptoms can include:
  • fatigue (lack of energy)
  • depression
  • dry skin
  • constipation
  • muscle weakness
  • hyperglycemia (high blood sugar level)
• Nephritis (inflammation in your kidneys) that’s caused by an immune system reaction. Symptoms can include:
  • urinating more often than usual
  • burning sensation when you’re urinating
  • pain in your pelvis
  • cloudy or bloody urine
  • fever
  • swelling, which commonly occurs in your feet, legs, and face
• Infusion reaction (an immune system reaction that happens during or shortly after receiving a drug infusion). Symptoms can include:
  • fever
  • chills
  • itchy skin
  • wheezing
  • rash
  • low blood pressure

Other serious side effects, which are explained in more detail below in “Side effects details,” include:

• pneumonitis (inflammation in your lungs)
• severe skin rashes

Side effect details

You may wonder how often certain side effects occur with this drug, or whether certain side effects pertain to it. Here’s some detail on several of the side effects this drug may or may not cause.

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Keytruda. In one clinical study, 0.4% of people stopped taking Keytruda because of allergic reaction to the drug.

Symptoms of a mild allergic reaction can include:

• skin rash
• itchiness
• flushing (warmth and redness in your skin)

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:

• angioedema (swelling under your skin, typically in your eyelids, lips, hands, or feet)
• swelling of your tongue, mouth, or throat
• trouble breathing

Call your doctor right away if you have a severe allergic reaction to Keytruda. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency.

Other reactions

With an allergic reaction, your immune system reacts to certain substances, such as drugs, inside your body. Other reactions of the immune system have also occurred with Keytruda. These immune reactions cause inflammation in specific organs or body parts.

Examples of immune reactions that can occur with Keytruda use include:

• pancreatitis (inflammation in your pancreas)
• arthritis (inflammation in your joints)
• myasthenia gravis (inflammation in your skeletal muscles)
• uveitis (inflammation in a certain area of your eye)
• encephalitis (inflammation in your brain)

Symptoms of immune reactions vary depending on which area of your body is affected. If you’re having pain or other unusual symptoms, and you think you’re having an immune reaction, call your doctor right away.

Rash

Rash is one of the most common side effects of Keytruda. In clinical studies, up to 24% of people taking Keytruda alone had a rash. In the studies, different types of rashes were seen. These types included maculopapular rashes (rashes made up of red bumps or flat, red patches) and pruritic rashes (rashes that cause itching).

Rashes caused by Keytruda may also be a symptom of a more serious immune system reaction. In clinical studies, serious rashes occurred, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN).

SJS and TEN are severe, painful conditions that cause blisters on your body. They’re each diagnosed based on the percentage of your body surface area that’s affected. Each rash is diagnosed as follows:

• with SJS, less than 10% of your body is affected
• with TEN, more than 30% of your body is affected

Other symptoms of serious skin rashes include:

• burning pain on your skin
• itchy skin
• fever
• flu-like symptoms, such as chills, body aches, and muscle aches

Serious skin rashes can cause layers of your skin to peel off, leaving open sores exposed. Because these rashes can sometimes be life threatening, they require medical treatment right away.

If you have any form of skin rash while you’re taking Keytruda, call your doctor. They’ll recommend whether or not your condition needs medical attention right away.

Pneumonitis

Pneumonitis (inflammation in your lungs) is a serious, and possibly life threatening, side effect of Keytruda.

Pneumonitis is an immune system reaction that’s triggered by an outside substance, such as Keytruda. Symptoms of pneumonitis include:

• headache
• fever
• chills
• muscle aches
• tightness in your chest
• dry cough

In clinical studies of people with non-small cell lung cancer (NSCLC), up to 8.2% had pneumonitis while taking Keytruda. The studies reported that the risk of pneumonitis was higher for people who’d had radiation therapy to their lung and chest area in the past than in people who hadn’t had past radiation therapy.

For many people in the studies, their pneumonitis was treated with high dose corticosteroids. (These drugs helped to reduce inflammation in people’s lungs.) About half of the people were successfully treated. However, 3.7% of people in the studies stopped taking Keytruda because of pneumonitis.

Pneumonitis also occurred in people who took Keytruda for other types of cancer. In clinical studies of cancers other than lung cancer, 3.4% of people taking Keytruda had pneumonitis. The condition was successfully treated in more than half of the people. However, 1.3% of these people stopped taking Keytruda because of pneumonitis.

If you’re concerned about developing pneumonitis with Keytruda treatment, talk with your doctor. And if you have any symptoms of pneumonitis while taking Keytruda, call you doctor right away.

Hair loss

It’s possible to have hair loss while you’re taking Keytruda. In fact, during clinical studies of people with lung cancer, hair loss occurred in up to 47% of people taking Keytruda with chemotherapy. (Chemotherapy describes traditional drugs used to treat cancer.) Of people taking chemotherapy without Keytruda, up to 36% had hair loss.

Hair loss is a common concern for people having cancer treatment. However, this side effect is usually temporary, and it often improves once treatment is complete.

If you have questions about your risk of hair loss during Keytruda treatment, talk with your doctor. They can recommend ways to help manage this side effect during your treatment.

Diarrhea

In clinical studies, diarrhea was one of the most common side effects of Keytruda. When Keytruda was used alone, up to 28% of people taking it had diarrhea. And when Keytruda was used in combination with other drugs, up to 64% of people had diarrhea.

However, diarrhea may also be a symptom of immune-mediated colitis. This condition is a serious side effect of Keytruda. Immune-mediated colitis is inflammation in your colon that’s caused by an immune system reaction to the drug. It leads to diarrhea, belly pain, bloating, and fever.

In clinical studies, 1.7% of people who took Keytruda had immune-mediated colitis. For most people, the condition was successfully treated with corticosteroids. But 0.5% of people stopped taking Keytruda because of this side effect.

If you have diarrhea during Keytruda treatment, and it lasts longer than a few days, call your doctor. They’ll be able to recommend whether you need treatment for the diarrhea.

They may also check to make sure you aren’t dehydrated (having a low body fluid level). (In some cases, diarrhea can lead to dehydration.) Your doctor can also recommend whether you need medical treatment for dehydration.

Fever

Fever is one of the most common side effects of Keytruda. In clinical studies, between 10% and 28% of people taking the drug had a fever. In one study of people with lung cancer, 2% of people stopped taking Keytruda until their fever went away.

If you have a fever while you’re taking Keytruda, talk with your doctor. They can recommend safe medications for you to take to lower your body temperature and help you feel better.

Fatigue

In clinical studies, fatigue (lack of energy) was one of the most common side effects of Keytruda. In fact, between 23% and 65% of people taking Keytruda had fatigue during treatment.

If you feel fatigued while you’re using Keytruda, talk with your doctor. They can recommend ways to help improve your energy level during treatment. For example, certain exercises (such as yoga) or cognitive behavioral therapy may help reduce your fatigue.

Kidney failure

Kidney failure wasn’t a side effect of Keytruda seen in clinical studies. However, immune system reactions that cause nephritis (inflammation in your kidneys) have occurred with Keytruda use.

In some cases, nephritis can be a serious condition. And if it’s not treated, it could possibly lead to severe kidney problems, such as kidney failure. Symptoms of nephritis can include changes in urination and pain in your pelvis.

In clinical studies, nephritis occurred in 0.3% of people who took Keytruda on its own. And of those who took Keytruda with other cancer drugs, 1.7% had nephritis.

During Keytruda treatment, your doctor will monitor your kidney function. If you develop nephritis, your doctor will likely prescribe corticosteroids to reduce the inflammation in your kidneys.

If you have any symptoms of nephritis during Keytruda treatment, call you doctor. They can recommend whether you need medical treatment.

Side effects in children

The side effects of Keytruda seen in children are similar to those seen in adults. However, in a small clinical study, children who took Keytruda had higher rates of certain side effects than did adults using the drug.

Side effects of Keytruda that were more common in children than in adults included:

• fatigue (lack of energy)
• vomiting
• belly pain
• hyponatremia (low sodium level)
• elevated liver enzymes (certain types of proteins)

If you have questions or concerns about side effects in children using Keytruda, talk with your pharmacist or your child’s doctor.

Keytruda cost

As with all medications, the cost of Keytruda can vary. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use.

Financial and insurance assistance

If you need financial support to pay for Keytruda, or if you need help understanding your insurance coverage, help is available.

Merck Sharp & Dohme Corp., the manufacturer of Keytruda, offers a program called The Merck Access Program. For more information and to find out if you’re eligible for support, call 855-257-3932 or visit the program website.

Alternatives to Keytruda

Other drugs are available that can treat your condition. Some may be better suited for you than others. If you’re interested in finding an alternative to Keytruda, talk with your doctor. They can tell you about other medications that may work well for you.

Keytruda is used to treat several types of cancer in adults and children. It’s called an immunotherapy drug. These types of drugs tell certain parts of your immune system to attack cancer cells.

Examples of other immunotherapy drugs that may be used to treat different types of cancers include:

• alemtuzumab (Campath)
• trastuzumab (Herceptin, Herzuma, Ogivri)
• nivolumab (Opdivo)
• cemiplimab (Libtayo)
• atezolizumab (Tecentriq)
• avelumab (Bavencio)
• durvalumab (Imfinzi)
• ipilimumab (Yervoy)
• bevacizumab (Avastin, Mvasi)
• cetuximab (Erbitux)

Note: Some of the drugs listed above are used off-label to treat certain forms of cancer. With off-label use, a drug that’s approved to treat certain conditions is used to treat another condition.

Keytruda vs. Opdivo

You may wonder how Keytruda compares to other medications that are prescribed for similar uses. Here we look at how Keytruda and Opdivo are alike and different.

Ingredients

Keytruda contains the drug pembrolizumab, while Opdivo contains the drug nivolumab.

Uses

Keytruda and Opdivo are both approved to treat certain types of the following cancers:

• melanoma
• non-small cell lung cancer (NSCLC)
• renal cell carcinoma (kidney cancer)
• classical Hodgkin lymphoma (cHL)
• head and neck squamous cell cancer (HNSCC)
• esophageal cancer
• gastric cancer (stomach cancer)
• gastroesophageal cancer
• urothelial carcinoma (bladder cancer)
• colorectal cancer with either microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) gene mutations*
• hepatocellular carcinoma (liver cancer)

* Gene mutations are abnormal changes in a gene.

Keytruda is also approved to treat:

• primary mediastinal large B-cell lymphoma (PMBCL)
• solid tumors with MSI-H or dMMR mutations or those with a high level of certain mutationscalled tumor mutational burden-high (TMB-H)
• cervical cancer
• Merkel cell carcinoma (MCC)
• cutaneous squamous cell carcinoma (cSCC)
• endometrial cancer
• triple-negative breast cancer

And Opdivo is also approved to treat:

• mesothelioma

Drug forms and administration

Keytruda and Opdivo are both given by intravenous (IV) infusion by healthcare providers. With an IV infusion, the drug is injected into your vein over a period of time. Keytruda and Opdivo infusions typically last at least 30 minutes.

Keytruda infusions are given once every 3 or 6 weeks. On the other hand, Opdivo infusions may be given once every 2, 3, or 4 weeks.

Side effects and risks

Keytruda and Opdivo contain different drugs that work in similar ways. Therefore, both medications can cause very similar side effects. Below are examples of these side effects.

More common side effects

These lists contain examples of more common side effects that can occur with Keytruda when it’s used alone, with Opdivo when it’s used alone, or with both drugs (when taken individually).

• Can occur with Keytruda:
  • few unique common side effects
• Can occur with Opdivo:
  • back pain
  • upper respiratory infections, such as the common cold
  • headache
  • vomiting
• Can occur with both Keytruda and Opdivo:
  • fatigue (lack of energy)
  • rash
  • muscle or bone pain
  • itchy skin
  • diarrhea
  • nausea
  • cough
  • shortness of breath
  • constipation
  • decreased appetite
  • fever
  • belly pain

Serious side effects

These lists contain examples of serious side effects that can occur with Keytruda, with Opdivo, or with both drugs (when taken individually).

• Can occur with Keytruda:
  • few unique serious side effects
• Can occur with Opdivo:
  • encephalitis (inflammation in your brain)
• Can occur with both Keytruda and Opdivo:
  • pneumonitis (inflammation in your lungs)
  • colitis (inflammation in your colon)
  • hepatitis (inflammation in your liver) or liver damage
  • hormone disorders
  • kidney problems, including nephritis (inflammation in your kidneys)
  • severe skin rashes
  • severe allergic reaction
  • infusion reaction (an immune system reaction that happens during or shortly after receiving a drug infusion)

Effectiveness

Keytruda and Opdivo have different approved uses, but they’re both used to treat certain types of the following cancers:

• melanoma
• non-small cell lung cancer (NSCLC)
• renal cell carcinoma (kidney cancer)
• classical Hodgkin lymphoma (cHL)
• head and neck squamous cell cancer (HNSCC)
• urothelial carcinoma (bladder cancer)
• esophageal cancer
• gastric cancer (stomach cancer)
• gastroesophageal cancer
• colorectal cancer with either MSI-H or dMMR gene mutations
• hepatocellular carcinoma (liver cancer)

These drugs haven’t been directly compared in clinical studies. But separate studies have found both Keytruda and Opdivo to be effective in treating these types of cancers.

One indirect comparison pooled the results of several studies of Keytruda and Opdivo. This comparison found that both drugs had similar effectiveness in treating NSCLC. Another analysis that combined the results of several studies also found these drugs had similar effectiveness in treating NSCLC.

Costs

Keytruda and Opdivo are both brand-name drugs. There are currently no generic forms of either drug. Brand-name medications usually cost more than generics.

The actual price you’ll pay for either drug depends on your insurance plan, your location, and the facility where you receive your treatments.

Keytruda vs. Tecentriq

You may wonder how Keytruda compares to other medications that are prescribed for similar uses. Here we look at how Keytruda and Tecentriq are alike and different.

Ingredients

Keytruda contains the drug pembrolizumab, while Tecentriq contains the drug atezolizumab.

Uses

Keytruda and Tecentriq are both approved to treat certain types of the following cancers:

• urothelial cancer (bladder cancer)
• non-small cell lung cancer (NSCLC)
• hepatocellular carcinoma (liver cancer)
• melanoma

Tecentriq is also approved to treat certain types of:

• small cell lung cancer (SCLC)

Keytruda is also approved to treat certain types of:

• renal cell carcinoma (kidney cancer)
• classical Hodgkin lymphoma (cHL)
• head and neck squamous cell cancer (HNSCC)
• colorectal cancer with either microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) gene mutations*
• primary mediastinal large B-cell lymphoma (PMBCL)
• solid tumors with either MSI-H or dMMR gene mutations or those with a high level of gene mutations called tumor mutational burden (TMB-H)
• gastric cancer (stomach cancer)
• esophageal cancer
• gastroesophageal cancer
• cervical cancer
• Merkel cell carcinoma (MCC)
• cutaneous squamous cell carcinoma (cSCC)
• endometrial cancer
• esophageal cancer
• triple-negative breast cancer

* Gene mutations are abnormal changes in a gene.

Drug forms and administration

Keytruda and Tecentriq are both given by intravenous (IV) infusion by healthcare providers. With an IV infusion, the drug is injected into your vein over a period of time. Keytruda and Tecentriq infusions typically last at least 30 minutes. But Tecentriq infusions may last a while longer.

Keytruda infusions are given once every 3 or 6 weeks. However, for most conditions, Tecentriq infusions are given once every 2, 3, or 4 weeks.

Side effects and risks

Keytruda and Tecentriq contain different drugs that work in similar ways. Therefore, both medications can cause very similar side effects. Below are examples of these side effects.

More common side effects

These lists contain examples of more common side effects that can occur with Keytruda, with Tecentriq, or with both drugs (when taken individually).

• Can occur with Keytruda:
  • muscle or bone pain
  • itchy skin
  • diarrhea
  • rash
  • fever
  • constipation
  • belly pain
• Can occur with Tecentriq:
  • weakness
• Can occur with both Keytruda and Tecentriq:
  • fatigue (lack of energy)
  • nausea
  • cough
  • shortness of breath
  • decreased appetite

Serious side effects

These lists contain examples of serious side effects that can occur with Keytruda, with Tecentriq, or with both drugs (when taken individually).

• Can occur with Keytruda:
  • nephritis (inflammation in your kidneys)
  • severe skin reactions
• Can occur with Tecentriq:
  • severe infections, including urinary tract infections (UTIs) and pneumonia
• Can occur with both Keytruda and Tecentriq:
  • colitis (inflammation in your colon)
  • hepatitis (inflammation in your liver) or liver damage
  • pneumonitis (inflammation in your lungs)
  • hormone disorders
  • infusion reaction (an immune system reaction that happens during or shortly after receiving a drug infusion)
  • severe allergic reaction

Effectiveness

Keytruda and Tecentriq have different FDA-approved uses, but they’re both used to treat urothelial cancer (bladder cancer), non-small cell lung cancer (NSCLC), and others.

These drugs haven’t been directly compared in clinical studies. But separate studies have found both Keytruda and Tecentriq to be effective in treating certain types of bladder cancer, NSCLC, and SCLC.

In addition, the two drugs have been indirectly compared as treatment options for NSCLC. One review that combined the results of several studies found that Keytruda was more effective than Tecentriq in treating NSCLC. However, another review found that the two drugs may have similar effectiveness in treating NSCLC.

Costs

Keytruda and Tecentriq are both brand-name drugs. There are currently no generic forms of either drug. Brand-name medications usually cost more than generics.

The actual price you’ll pay for either drug depends on your insurance plan, your location, and the facility where you receive your treatments.

Keytruda dosage

The information in this section describes Keytruda dosages that are commonly used or recommended. But keep in mind that your doctor will determine the best dosage to suit your needs.

The Keytruda dosage your doctor prescribes for you will depend on your age. The sections below list typical dosages that are given to adults and children.

Drug forms and strengths

Keytruda contains the drug pembrolizumab. It comes as a liquid solution that’s available in one strength: 100 mg/4 mL.

Keytruda is given by healthcare providers as an intravenous (IV) infusion. With an IV infusion, the drug is injected into your vein over a period of time. Keytruda infusions typically last about 30 minutes.

Dosage for adults

The typical dosage of Keytruda varies based on the condition it’s used to treat. You’ll likely receive 200-mg doses once every 3 weeks or 400-mg doses once every 6 weeks.

Pediatric dosage

The usual dosage of Keytruda for children is 2 mg of drug per kilogram of their body weight. (A kilogram is equal to about 2.2 pounds.) The maximum dose of Keytruda that a child can receive is 200 mg.

For example, a child who weighs 50 pounds (about 23 kilograms) would receive 45 mg of Keytruda in each dose.

As with adults, Keytruda is also given to children as an IV infusion once every 3 weeks.

What if I miss a dose?

If you forget or miss your appointment for a Keytruda infusion, call your doctor’s office right away. The medical staff will help you reschedule your appointment.

Will I need to use this drug long term?

It depends. Keytruda is given for different lengths of time depending on how each person’s body responds to the drug.

Keytruda is typically given until your cancer either gets worse or you have bothersome or severe side effects. But even if your cancer doesn’t get worse and your side effects are manageable, Keytruda is used for no longer than a set length of time. This is because the safety and effectiveness of Keytruda treatment that lasts longer than a certain length of time hasn’t been studied.

For example, if the drug is stopping the cancer from getting worse, Keytruda can be used for up to 1 year in adults with melanoma who are taking Keytruda as adjuvant therapy. (Adjuvant therapy is treatment that’s given after surgery or medication to prevent someone’s cancer from coming back.)

In addition, Keytruda can be used for up to 2 years if it’s stopping the following types of cancer from getting worse:

• non-small cell lung cancer (NSCLC)
• head and neck squamous cell cancer (HNSCC)
• classical Hodgkin lymphoma (cHL)
• primary mediastinal large B-cell lymphoma (PMBCL)
• urothelial cancer (bladder cancer)
• microsatellite instability-high cancer (MSI-H cancer)
• gastric cancer (stomach cancer)
• cervical cancer
• hepatocellular cancer (liver cancer)
• Merkel cell carcinoma (MCC)
• renal cell carcinoma (kidney cancer)
• esophageal cancer
• endometrial cancer

Your doctor will monitor how your body responds to Keytruda. And they’ll recommend the appropriate length of time for you to take Keytruda.

Keytruda and alcohol

There aren’t any known interactions between Keytruda and alcohol.

However, Keytruda and alcohol can cause similar side effects, including nausea, diarrhea, and fatigue (lack of energy). If you drink too much alcohol during Keytruda treatment, these side effects could be worsened.

Talk with your doctor about whether it’s safe for you to drink alcohol during Keytruda treatment.

Keytruda interactions

Keytruda isn’t expected to interact with many medications, supplements, or foods. However, be sure to tell your doctor and pharmacist about all of the prescription drugs and over-the-counter products you take.

Different interactions can cause different effects. For instance, some interactions can interfere with how well a drug works. Other interactions can increase side effects or make them more severe.

Keytruda and other medications

Below we describe one medication that can interact with Keytruda. But this isn’t the only medication that may interact with Keytruda.

Before taking Keytruda, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Keytruda and axitinib

Taking Keytruda with another cancer drug called axitinib (Inlyta) increases your risk of liver damage. This risk is increased compared with using Keytruda alone.

Possible symptoms of liver damage may include:

• nausea or vomiting
• jaundice (yellowing of your skin or the whites of your eyes)
• pain on the right side of your belly
• dark or cloudy urine
• bruising more often than usual
• bleeding that doesn’t stop

If you’re taking Keytruda in combination with axitinib, your doctor will closely monitor your liver function. They’ll do this by checking certain blood tests.

If you have any symptoms of liver damage during treatment, call your doctor right away.

Keytruda and herbs and supplements

There aren’t any herbs or supplements that have been specifically reported to interact with Keytruda. However, you should still check with your doctor or pharmacist before using any of these products while taking Keytruda.

Keytruda and foods

There aren’t any foods that are known to interact with Keytruda. If you have questions about avoiding certain foods during Keytruda treatment, talk with your doctor or pharmacist.

Keytruda use with other drugs

When it’s used to treat certain types of cancer, Keytruda is approved for use in combination with other drugs.

For example, Keytruda is used with other drugs to treat non-small cell lung cancer (NSCLC). Drugs that are used with Keytruda for this purpose include:

• pemetrexed (Alimta)
• carboplatin
• paclitaxel (Abraxane)
• cisplatin
• oxaliplatin (Eloxatin)

And Keytruda is taken in combination with a cancer drug called axitinib (Inlyta) when it’s used to treat renal cell carcinoma (kidney cancer).

If you have questions about whether you’ll need to use other medications with Keytruda, talk with your doctor.

How Keytruda works

Keytruda is used to treat several types of cancer. It belongs to a class of drugs called PD-1 inhibitors.

Keytruda is called a monoclonal antibody, which is a type of drug that’s developed from immune system cells inside a lab. It’s also called an immunotherapy drug. This means that it tells certain parts of your immune system to attack cancer cells.

Keytruda works by inhibiting (blocking) the activity of an immune system protein called PD-L1. This protein is also referred to as a checkpoint protein.

This checkpoint protein attaches (binds) to PD-1 receptors (attachment sites). PD-1 receptors are found on normal cells and cancer cells.

When PD-L1 attaches to PD-1 receptors, this tells certain immune system cells called T cells to stop attacking “foreign” invaders. (Cancer cells are an example of cells that your body sees as foreign invaders.) The action of PD-1 receptors allows cancer cells in your body to continue to grow without being attacked.

Some cancer cells have a large number of PD-1 receptors. The extra PD-1 receptors help the cancer cells to survive without being attacked by your immune system’s T cells.

Keytruda attaches to PD-1 receptors so that PD-L1 checkpoint proteins can’t attach to them. By blocking the action of PD-L1, Keytruda allows your T cells to continue attacking cancer cells. This boost in immune system function helps prevent your cancer from getting worse.

How long does it take to work?

Keytruda starts working with your immune system soon after you start taking the drug. But because Keytruda is working to prevent cancer growth, it’s hard to say how long it takes to work.

Every few weeks during treatment, your doctor will monitor your cancer to see whether it’s growing or spreading. Talk with your doctor about how they’ll check your treatment progress while you’re using Keytruda.

Keytruda precautions

Before taking Keytruda, talk with your doctor about your health history. Keytruda may not be right for you if you have certain medical conditions. These include:

• History of stem cell transplant. If you’ve had an allogenic stem cell transplant (received stem cells from a donor), you may be at greater risk for graft-versus-host-disease after Keytruda treatment. With graft-versus-host-disease, your immune system attacks the transplanted stem cells. If you’ve had an allogenic stem cell transplant, talk with your doctor about whether Keytruda is safe for you.
• Receiving certain treatments for multiple myeloma. Using Keytruda with certain other drugs used to treat multiple myeloma is related to an increased risk of death. Be sure to tell your doctor if you’re receiving treatment for multiple myeloma.
• Pregnancy. Keytruda may cause harm to a developing fetus. Because of this, it’s recommended that you use an effective form of birth control during Keytruda treatment. And you should continue to use birth control for at least 4 months after your last dose of Keytruda. For more information, please see the “Keytruda and pregnancy” section below.
• Breastfeeding. Keytruda may cause harm to a child who is breastfed by a female taking the drug. Breastfeeding is not recommended during Keytruda treatment or for at least 4 months after your last dose of the drug. For more information, please see the “Keytruda and breastfeeding” section below.
• Allergy to Keytruda. If you’ve had a severe allergic reaction to a Keytruda infusion in the past, you shouldn’t take Keytruda. If you’re unsure if you’ve had a severe allergic reaction to Keytruda, talk with your doctor.

Note: For more information about the potential negative effects of Keytruda, see the “Keytruda side effects” section above.

Keytruda and pregnancy

There aren’t any human or animal studies that have shown whether Keytruda is safe to take during pregnancy. However, it’s thought that Keytruda’s activity in your body is harmful to a developing fetus.

Some animal studies tested drugs with activity similar to Keytruda’s activity. These studies have shown increased rates of miscarriage and stillbirth in pregnant females who received the drugs. But keep in mind that animal studies don’t always predict what will happen in humans.

Because this drug may not be safe to use during pregnancy, doctors will check for pregnancy before giving Keytruda to women who are able to become pregnant.

If you’re pregnant, talk with your doctor before starting Keytruda. And if you become pregnant while taking Keytruda, call your doctor right away.

Keytruda and birth control

It’s thought that Keytruda may be harmful to a developing pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while you’re using Keytruda.

Note: Sex and gender exist on spectrums. Use of the terms “male” and “female” below refers to sex assigned at birth.

For females using Keytruda

If you’re a female who’s sexually active and able to become pregnant, you should use a reliable form of birth control while taking Keytruda. And you should continue to use birth control for at least 4 months after your last dose of the drug.

For males using Keytruda

The manufacturer of Keytruda hasn’t stated whether males using Keytruda need to use birth control. If you’re a male who’s sexually active with a female partner who is able to become pregnant, talk with your doctor about your birth control needs during Keytruda treatment.

Keytruda and breastfeeding

There haven’t been any studies in animals or humans to show whether it’s safe to use Keytruda while breastfeeding.

However, because of the serious side effects that Keytruda may cause, it’s recommended that you don’t breastfeed during Keytruda treatment. And you shouldn’t breastfeed for at least 4 months after your last dose of Keytruda.

If you’re using Keytruda and considering breastfeeding, talk with your doctor. They can recommend safe and healthy ways to feed your child.

Common questions about Keytruda

Here are answers to some frequently asked questions about Keytruda.

What’s the success rate of Keytruda?

That’s different for each type of cancer that Keytruda is used to treat. And your individual response to Keytruda treatment will also be unique based on the form of cancer you have and your overall health.

In many clinical studies, Keytruda was successful in shrinking the size of people’s tumors and reducing how quickly their cancer worsened.

For example, in one study, up to 6% of people taking Keytruda for melanoma had their cancer completely go away. In another study, 22% of people taking Keytruda for classical Hodgkin lymphoma (cHL) had their cancer completely go away.

The number of people who had their cancer partially go away was typically much higher in each study. (For example, it was up to 47% for people with cHL).

For more information about the effectiveness of Keytruda, see the section “Keytruda uses” above. And be sure to talk with your doctor about what you can expect with Keytruda treatment.

How much longer will I live if I take Keytruda?

That depends on several factors, including the type and stage of your cancer, your age, and your overall health.

During clinical studies, Keytruda was used to treat many different types of cancer. In some cases, people taking Keytruda lived several months longer than people taking either other cancer drugs or a placebo (treatment with no active drug).

For more information about the effectiveness of Keytruda, see the section “Keytruda uses” above. And be sure to talk with your doctor about your possible results with Keytruda treatment.

Have side effects of Keytruda been linked with deaths?

Yes, some serious side effects of Keytruda have been fatal, but these deaths have been rare. These serious side effects can occur when your immune system reacts to Keytruda. For example, certain immune system reactions can lead to organ damage or organ failure.

Examples of immune system reactions that may occur with Keytruda treatment include:

• pneumonitis (inflammation in your lungs), which can lead to pneumonia and respiratory failure
• severe skin reactions, such as Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)
• reactions to stem cell transplants
• hepatitis (inflammation in your liver)

In clinical studies, as many as 0.1% of people taking Keytruda to treat different types of cancer died from pneumonitis. Also, in one study, 0.3% of people taking Keytruda to treat head and neck cancer died from pneumonitis.

Your doctor will closely monitor you for immune reactions. They can also tell you of any symptoms to watch for. If think you may be having an immune reaction to Keytruda, call your doctor right away.

How are immunotherapy and chemotherapy different?

Immunotherapy drugs, such as Keytruda, work by helping your immune system fight diseases. This includes diseases such as cancer. Immunotherapy drugs may do this by boosting your immune system so that it recognizes and attacks cancer cells. The drugs may also work by increasing the level of immune system proteins in your body.

Immunotherapy drugs are a type of targeted treatment. They’re often designed to target (work on) certain types of cancers with very specific gene mutations (abnormal changes). This makes immunotherapy drugs tailored to each person who’s receiving them.

On the other hand, chemotherapy (traditional drugs used to treat cancer) works by stopping cells in your body from dividing. (Cells that are dividing are making more cells.)

But chemotherapy drugs aren’t made to only target cells with specific gene mutations. Instead, chemotherapy works on most of the quickly dividing cells in your body. This includes both cancer cells and some healthy cells. Chemotherapy doesn’t just work on cancer cells.

In some cases, your doctor may prescribe a combination of chemotherapy and immunotherapy drugs for you. This is done in order to treat your cancer in more than one way.

Will my doctor order a lab test to check whether Keytruda is right for me?

Yes, they will most likely do that. Keytruda is used to treat certain types of cancer that have high levels of a protein called PD-L1. This protein is found on some cancer cells and on some healthy cells.

Some people’s cancer cells have more PD-L1 protein than other people’s cancer cells do. Because Keytruda works to block this protein, it’s used to treat cancers that have more of the protein.

If you have certain types of cancer, your doctor will order a test for you to see if you have elevated levels of PD-L1.

Some types of cancer have unique traits other than PD-L1 that help Keytruda work on them. (And just like the PD-L1 test, certain lab tests can be used to check for these traits.) For example, some solid tumors or colon cancers have genetic mutations (abnormal changes) that make Keytruda a good treatment choice.

Before your doctor prescribes Keytruda, they’ll check any tests that are needed to make sure it’s the right drug for you.