Care During Chemotherapy and Beyond


(SEm ip LI mab)

Trade Name(s): Libtayo®

Cemiplimab-rwlc is the generic name for the trade name drug Libtayo. In some cases, health care professionals may use the trade name Libtayo when referring to the generic drug name cemiplimab-rwlx, or just cemiplimab.

Drug Type: Cemiplimab-rwlc is a monoclonal antibody (for more detail, see "How Cemiplimab Works" below).

What Cemiplimab Is Used For

  • Treatment of metastatic cutaneous squamous cell carcinoma
  • Treatment of locally advanced cutaneous squamous cell carcinoma that is not amenable for curative surgery or radiation
  • Treatment of locally advanced and metastatic basal cell carcinoma
  • Treatment of patients with advanced non-small cell lung cancer (NSCLC) whose tumors have high PD-L1 expression.

Note: If a drug has been approved for one use, physicians may elect to use this same drug for other problems if they believe it may be helpful.

How Cemiplimab Is Given

  • Cemiplimab is given by an infusion into the vein (intravenous or IV) over 30 minutes every 3 weeks.

Side Effects

Important things to remember about the side effects of cemiplimab:

  • Most people will not experience all of the side effects listed.
  • There are many options to minimize or prevent side effects.
  • There is no relationship between the presence or severity of side effects and the effectiveness of the medication.

The following side effects are common (occurring in greater than 20%) for patients taking cemiplimab:

These are less common side effects (occurring in 10-19%) for patients receiving cemiplimab:

A rare but serious side effect of cemiplimab may be immune-related reaction. This immune-related reaction occurs when the immune system attacks normal cells in the body. When this side effect occurs, it affects primarily the skin, bowels, liver, nerves, and endocrine system, but virtually any organ system can be affected. This can occur during treatment but can also be seen weeks or months after discontinuation of treatment. Symptoms of this reaction will be monitored throughout treatment. Lab work will check for elevated liver enzymes and thyroid function.

Contact your healthcare provider right away if you have any new or worsening symptoms.

Not all side effects are listed above. Some that are rare (occurring in less than 10% of patients) are not listed here. However, you should always inform your healthcare provider if you experience any unusual symptoms.

When to Contact Your Doctor or Health Care Provider

Contact your health care provider immediately, day or night, if you should experience any of the following symptoms:

  • Confusion or hallucinations
  • Dark, tarry or bloody stools with or without severe stomach pain
  • Red, swollen, blistered or peeling skin
  • Any signs of the rare but serious complications listed above under "Side Effects"
  • Signs of reaction to the drug (wheezing, chest tightness, itching, bad cough, swelling of the face, lips, or throat).

The following symptoms require medical attention, but are not an emergency. Contact your health care provider within 24 hours of noticing any of the following:

  • Nausea (interferes with ability to eat and unrelieved with prescribed medication)
  • Vomiting (vomiting more than 4-5 times in a 24-hour period)
  • Diarrhea (4-6 episodes in a 24-hour period)
  • Black or tarry stools, or blood in your stools
  • Unusual bleeding or bruising
  • Blood in the urine
  • Skin or the whites of your eyes turn yellow
  • Urine turns dark or brown (tea color)
  • Skin rash with or without itching
  • Unusual weakness of legs, arms or face
  • Persistent or unusual headaches
  • Extreme fatigue (unable to carry on self-care activities)
  • Mouth sores (painful redness, swelling or ulcers)


  • Before starting cemiplimab treatment, make sure you tell your doctor about any other medications you are taking (including prescription, over-the-counter, vitamins, herbal remedies, etc.)
  • Do not receive any kind of immunization or vaccination without your doctor's approval while taking cemiplimab.
  • Inform your health care professional if you are pregnant or may be pregnant prior to starting
  • Men and women of childbearing potential should use effective contraception and not conceive a child while taking cemiplimab. Barrier methods of contraception, such as condoms, are recommended during treatment with cemiplimab and for at least 4 months after the last dose of cemiplimab.
  • Do not breast feed while taking cemiplimab and for at least 4 months after the last dose due to the potential of serious adverse reactions in breastfed infants.
  • Let all other healthcare providers, including emergency room staff, know that you are taking cemiplimab so they can manage your plan of care appropriately.

Self-Care Tips

  • Drink at least two to three quarts of fluid every 24 hours, unless you are instructed otherwise.
  • Avoid sun exposure. Wear SPF 30 (or higher) sun block and protective clothing.
  • In general, drinking alcoholic beverages should be kept to a minimum or avoided completely. You should discuss this with your doctor.
  • To reduce nausea, take anti-nausea medications as prescribed by your doctor, and eat small, frequent meals.
  • Get plenty of rest.
  • Maintain good nutrition.
  • Remain active as you are able. Gentle exercise is encouraged such as a daily walk.
  • If you experience symptoms or side effects, be sure to discuss them with your health care team. They can prescribe medications and/or offer other suggestions that are effective in managing such problems.

Monitoring and Testing While Taking Cemiplimab

You will be checked regularly by your doctor while you are taking cemiplimab, to monitor side effects and check your response to therapy. Periodic blood work will be obtained to monitor your complete blood count (CBC) as well as the function of other organs (such as your kidneys and liver) will also be ordered by your doctor.

How Cemiplimab Works

Cemiplimab is classified as a monoclonal antibody. Monoclonal antibodies are a relatively new type of “targeted” cancer therapy.

Antibodies are an integral part of the body’s immune system. Normally, the body creates antibodies in response to an antigen that has entered the body. The antibodies attach to the antigen in order to mark it for destruction by the immune system.

To make monoclonal antibodies in the laboratory, scientists analyze specific antigens on the surface of the cancer cells. Then, using animal and human proteins they create an antibody that will target that antigen on the cancer cell.

Since monoclonal antibodies only target specific cells, they cause less toxicity to healthy cells. These medications can only be used in cancers that have this antigen identified.

Cemiplimab is a selective antibody directed against programmed death 1 (PD-1) receptor on the cell surface. The drug blocks the PD-1 receptor, preventing binding and activation of PD-L1 and PD-L2. This mechanism causes the activation of T-cell medicated immune responses against tumor cells.

Note: We strongly encourage you to talk with your health care professional about your specific medical condition and treatments. The information contained in this website is meant to be helpful and educational, but is not a substitute for medical advice. is designed to provide the latest information about chemotherapy to patients and their families, caregivers and friends. For information about the 4th Angel Mentoring Program visit