Retifanlimab-dlwr (Intravenous)

Retifanlimab-dlwr injection is used to treat a type of skin cancer called Merkel cell carcinoma (MCC) that has come back or spread.

This medicine should only be given by your doctor or under their direct supervision.

It is very important for your doctor to monitor your progress during regular visits to ensure that this medicine is working correctly. Blood and urine tests may be required to check for side effects.

Using this medicine while pregnant can harm your unborn baby. If you are a woman who can become pregnant, your doctor may perform a pregnancy test before you begin this medicine to confirm that you are not pregnant. Use an effective form of birth control to prevent pregnancy during treatment with this medicine and for 4 months after your last dose. If you think you might be pregnant while using this medicine, inform your doctor immediately.

Tell your doctor right away if you experience a cough, chest tightness, or any breathing problems while taking this medicine. These could be signs of a serious lung issue.

Colitis (inflammation of the colon or bowel) may occur with this medicine. Let your doctor know immediately if you experience stomach pain or tenderness, watery or bloody diarrhea, or a fever after receiving this medicine.

Contact your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, unusual tiredness or weakness, or yellowing of your eyes or skin. These could indicate a serious liver issue.

Serious problems with the adrenal, pituitary, or thyroid glands (hormone glands) may occur while you are using this medicine. Inform your doctor if you experience persistent or unusual headaches, changes in mood or behavior (e.g., irritability or forgetfulness), lightheadedness, dizziness, fainting, unusual sluggishness, or weight gain.

This medicine may affect your blood sugar levels. If you notice a change in your blood or urine sugar test results or have any questions, consult your doctor.

This medicine may lead to serious kidney issues (e.g., nephritis, kidney failure). Tell your doctor immediately if you have bloody or cloudy urine, nausea, vomiting, difficulty breathing, swelling of the face, feet, or lower legs, unusual tiredness or weakness, or unusual weight gain.

Serious skin reactions (e.g., exfoliative dermatitis, Stevens-Johnson syndrome, drug rash with eosinophilia and systemic syndrome (DRESS), and toxic epidermal necrolysis) can occur with this medicine. Contact your doctor right away if you experience blistering, peeling, or loosening of the skin, chills, cough, diarrhea, itching, joint or muscle pain, red irritated eyes, red skin lesions (often with a purple center), severe acne or skin rash, sores or ulcers on the skin, mouth, or lips, swollen glands, unusual bleeding or bruising, or unusual tiredness or weakness while using this medicine.

This medicine may cause infusion-related reactions, which can be life-threatening and require immediate medical attention. Inform your doctor right away if you experience fever, chills or shaking, dizziness, trouble breathing, itching or rash, lightheadedness, or fainting after receiving this medicine.

This medicine may increase your risk of possible organ transplant rejection. Discuss this risk with your doctor.

Call your doctor immediately if you have difficulty breathing, swallowing, or talking, muscle weakness, severe tiredness, or sudden numbness and weakness in your arms or legs. These could indicate a nervous system issue.

Consult your doctor if you have a headache, confusion, seizures, stiff neck, or vomiting while using this medicine. These may be signs of encephalitis.

Pancreatitis (inflammation of the pancreas) may occur while you are receiving this medicine. Inform your doctor immediately if you experience sudden and severe stomach pain, chills, constipation, nausea, vomiting, fever, or lightheadedness.

Tell your doctor right away if you notice changes in your eyesight, severe or persistent muscle or joint pain, or severe muscle weakness after receiving this medicine.

In deciding to use a medicine, you and your doctor will consider the risks of taking the medicine against the benefits it may provide. For this medicine, keep the following in mind:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medicines. Also, let your healthcare professional know if you have any other allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

Studies have not been done to determine how retifanlimab-dlwr injection affects children. Safety and effectiveness have not been established for this age group.

Geriatric

Current studies have not shown any specific problems in older adults that would limit the use of retifanlimab-dlwr injection.

Breast Feeding

There are not enough studies in women to determine the risk to infants when using this medication while breastfeeding. Consider the potential benefits and risks before using this medication during breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while in other cases, two different medicines may be used together even if there may be an interaction. In such cases, your doctor may need to adjust the dose or take other precautions. Inform your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicines.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be taken around mealtime or with specific types of food due to possible interactions. Using alcohol or tobacco with some medicines can also lead to interactions. Talk to your healthcare professional about using your medicine with food, alcohol, or tobacco.

Other Medical Problems

Having other medical problems may affect the use of this medicine. Be sure to tell your doctor if you have any other medical issues, especially:

• Colitis (inflammation of the bowels) or
• Diabetic ketoacidosis or
• Hepatitis (inflammation of the liver) or
• Hyperthyroidism (high levels of thyroid hormone) or
• Hypophysitis (inflammation of the pituitary gland) or
• Hypothyroidism (low levels of thyroid hormone) or
• Immune system problems or
• Nephritis (inflammation of the kidneys) or
• Nervous system problems (e.g., Guillain-Barré syndrome, myasthenia gravis) or
• Pneumonitis (inflammation of the lungs) or
• Type 1 diabetes—Use with caution. This may worsen these conditions.

• Organ transplant (e.g., kidney or liver transplant), recent—Use with caution. This may increase the risk of organ transplant rejection.

• Patients who have had allogeneic hematopoietic stem cell transplant (HSCT)—Use with caution. This may worsen side effects.

Along with its necessary effects, a medicine may cause some unwanted effects. Not all of these side effects may happen, but if they do, they might need medical attention.

Check with your doctor or nurse right away if any of the following side effects occur:

More common

• Back pain
• black, tarry stools
• blistering, peeling, or loosening of the skin
• bone pain
• chest pain
• chills
• constipation
• cough
• depressed mood
• diarrhea
• dizziness
• dry skin and hair
• fainting
• fast or irregular heartbeat
• feeling cold
• fever
• hair loss
• hoarseness or husky voice
• itching
• joint pain
• muscle cramps and stiffness
• nervousness
• painful or difficult urination
• red irritated eyes
• red skin lesions, often with a purple center
• sensitivity to heat
• slowed heartbeat
• sore throat
• sores, ulcers, or white spots in the mouth or on the lips
• swollen glands
• trouble breathing
• unusual bleeding or bruising
• unusual tiredness or weakness
• weight gain or loss

Less common

• Bloody or cloudy urine
• dark urine
• drowsiness
• general feeling of discomfort or illness
• headache
• light-colored stools
• nausea and vomiting
• stomach cramps
• swelling of the face, feet, or lower legs
• thickening of bronchial secretions
• upper right abdominal or stomach pain
• watery or bloody diarrhea
• yellow eyes and skin

Rare

• Anxiety
• bleeding gums
• bloating
• blurred vision
• burning feeling in the chest or stomach
• chest discomfort or tightness
• chest pain, possibly moving to the left arm, neck, or shoulder
• confusion
• constipation
• darkening of the skin
• decreased amount of urine
• difficulty in breathing, chewing, swallowing, or talking
• difficulty in moving
• double vision
• drooping eyelids
• dry mouth
• eye pain or redness
• flushing
• fruit-like breath odor
• heavier menstrual periods
• inability to move the arms and legs
• increased blood pressure
• increased hunger
• increased thirst
• increased urination
• indigestion
• irritability
• joint pain, swelling, or redness
• loss of appetite
• loss of consciousness
• lower back or side pain
• mental depression
• muscle aches or cramps
• nosebleeds
• numbness or tingling in the fingers, face, or feet
• pains in the stomach, side, or abdomen, possibly radiating to the back
• pale skin
• pinpoint red spots on the skin
• redness, soreness, or itching skin
• seizures
• sensitivity to light
• skin rash
• stiff neck or back
• stomach pain, discomfort, or upset
• sudden numbness and weakness in the arms and legs
• sweating
• tearing
• tenderness in the stomach area
• throbbing pain

Some side effects may happen that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or lessen some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Lack or loss of strength
• pain in the arms or legs

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Zynyz

Available Dosage Forms:

• Solution

Therapeutic Class: Antineoplastic Agent

Pharmacologic Class: Retifanlimab

Find detailed information on biosimilars for this medication.

A nurse or other trained health professional will give you this medicine. It is given through a needle placed into one of your veins. It must be given slowly, so the needle will have to remain in place for at least 30 minutes every 4 weeks.

This medicine comes with a Medication Guide. Read and follow these instructions carefully. Ask your doctor if you have any questions.

Missed Dose

This medicine needs to be given on a fixed schedule. If you miss a dose, call your doctor, home health caregiver, or treatment clinic for instructions.