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Cemiplimab Side Effects

Medically reviewed by Drugs.com. Last updated on Apr 6, 2023.

Applies to cemiplimab: intravenous solution.

Serious side effects of Cemiplimab

Along with its needed effects, cemiplimab may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking cemiplimab:

More common

Less common

Rare

Other side effects of Cemiplimab

Some side effects of cemiplimab may occur 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 reduce 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

For Healthcare Professionals

Applies to cemiplimab: intravenous solution.

General

The most common adverse reactions as a single agent were fatigue, musculoskeletal pain, rash, diarrhea, and anemia. The most common adverse reactions in combination with platinum-based chemotherapy were alopecia, musculoskeletal pain, nausea, fatigue, peripheral neuropathy, and decreased appetite.[Ref]

Cardiovascular

Clinically significant immune-mediated cardiac/vascular adverse reactions (including myocarditis, pericarditis, vasculitis) occurred at an incidence of less than 1% in patients who received this drug or were reported with the use of other programmed death receptor-1/ligand-1 (PD-1/PD-L1) blocking antibodies; severe or fatal cases have been reported for some of these adverse reactions.

Very common (10% or more): Hypertension (includes hypertension, increased blood pressure, hypertensive crisis; up to 17%)

Uncommon (0.1% to 1%): Myocarditis (includes myocarditis, autoimmune myocarditis, immune-mediated myocarditis), pericarditis (includes autoimmune pericarditis, pericarditis)

Frequency not reported: Vasculitis

Dermatologic

Very common (10% or more): Alopecia (up to 37%), rash (includes rash, maculopapular rash, dermatitis, erythema, eczema, bullous dermatitis, erythematous rash, acneiform dermatitis, psoriasis, contact dermatitis, blister, pemphigoid, papular rash, hand dermatitis, skin exfoliation, autoimmune dermatitis, pruritic rash, macular rash, pustular rash, urticaria, atopic dermatitis, drug eruption, asteatotic eczema, skin reaction, psoriasiform dermatitis, nummular eczema, exfoliative rash, immune-mediated dermatitis, dyshidrotic eczema, nodular rash, allergic dermatitis, lichen planus, skin toxicity, erythema nodosum, exfoliative dermatitis, generalized exfoliative dermatitis, erythema multiforme, parapsoriasis; up to 34%), pruritus (includes pruritus, allergic pruritus; up to 22%), skin infection (includes skin infection, cellulitis, fungal skin infection, staphylococcal skin infection; up to 11%), actinic keratosis (10%)

Common (1% to 10%): Immune-mediated dermatologic/skin adverse reactions

Frequency not reported: Severe cutaneous adverse reactions (including Stevens-Johnson syndrome, toxic epidermal necrolysis)

Immune-mediated skin adverse reactions occurred in 1.9% (24/1281) of patients receiving this drug, including grade 2 (0.8%) and grade 3 (0.9%) adverse reactions. Skin adverse reactions led to permanent discontinuation of this drug in 0.2% of patients and withholding of therapy in 1.3% of patients. Among the 24 patients with immune-mediated skin adverse reactions, the median time to onset was 2 months (range: 2 days to 17 months) and the median duration was 2.9 months (range: 8 days to 38.8 months). Systemic corticosteroids were required in all patients with immune-mediated skin adverse reactions, which resolved in 71% of the 24 patients. This drug was withheld in 17 patients, with 13 restarting therapy after symptom improvement; of these 13 patients, 5 had recurrence of the skin adverse reaction.

Endocrine

Hypothyroidism occurred in 7% (87/1281) of patients receiving this drug, including grade 2 (6%) and grade 3 (less than 0.1%) adverse reactions. Hypothyroidism led to permanent discontinuation of this drug in 0.2% of patients and withholding of therapy in 0.7% of patients. Among the 87 patients with hypothyroidism, the median time to onset was 4 months (range: 15 days to 18.9 months) with a median duration of 9.2 months (range: 1 day to 37.1 months). Systemic corticosteroids were required in 1 of 87 patients with hypothyroidism, which resolved in 6% of the 87 patients; the majority of patients with hypothyroidism required long-term thyroid hormone replacement. This drug was withheld in 9 patients, with 1 restarting therapy after symptom improvement; hypothyroidism did not reoccur in this patient.

Hyperthyroidism occurred in 3% (39/1281) of patients receiving this drug, including grade 2 (0.9%) and grade 3 (less than 0.1%) adverse reactions. Hyperthyroidism led to withholding of therapy in 0.5% of patients; no patient discontinued this drug due to hyperthyroidism. Among the 39 patients with hyperthyroidism, the median time to onset was 1.9 months (range: 20 days to 23.8 months) and the median duration was 1.9 months (range: 9 days to 32.7 months). Systemic corticosteroids were required in 3 of 39 patients with hyperthyroidism, which resolved in 56% of the 39 patients. This drug was withheld in 7 patients, with 2 restarting therapy after symptom improvement; neither patient had recurrence of hyperthyroidism.

Thyroiditis occurred in 0.6% (8/1281) of patients receiving this drug, including grade 2 (0.3%) adverse reactions. Thyroiditis led to withholding of therapy in 1 patient; no patient discontinued this drug due to thyroiditis. Thyroiditis resolved in 13% of the 8 patients; systemic corticosteroids were not required in any patient with thyroiditis.

Hypophysitis occurred in 0.5% (7/1281) of patients receiving this drug, including grade 2 (0.3%) and grade 3 (0.2%) adverse reactions. Hypophysitis led to permanent discontinuation of this drug in 1 patient and withholding of therapy in 2 patients; neither patient restarted therapy. Among the 7 patients with hypophysitis, the median time to onset was 7.4 months (range: 2.5 to 10.4 months) with a median duration of 2.7 months (range: 9 days to 34.9 months). Systemic corticosteroids were required in 6 of 7 patients with hypophysitis, which resolved in 14% of the 7 patients.

Adrenal insufficiency occurred in 0.5% (6/1281) of patients receiving this drug, including grade 3 (0.5%) adverse reactions. Adrenal insufficiency led to permanent discontinuation of this drug in 1 patient and withholding of therapy in 1 patient; therapy was not restarted. Among the 6 patients with adrenal insufficiency, the median time to onset was 7.5 months (range: 4.2 to 18.3 months) and the median duration was 2.9 months (range: 22 days to 6.1 months). Systemic corticosteroids were required in 5 of 6 patients with adrenal insufficiency; the majority of these patients remained on systemic corticosteroids. Adrenal insufficiency resolved in 17% of the 6 patients.

Type 1 diabetes mellitus occurred in 1 of 1281 patients (grade 4). No patient discontinued this drug and 1 patient had therapy withheld due to type 1 diabetes mellitus. Therapy was restarted in the patient after symptom improvement; the patient received long-term insulin therapy.

Clinically significant immune-mediated endocrine adverse reactions (including hypoparathyroidism) occurred at an incidence of less than 1% in patients who received this drug or were reported with the use of other PD-1/PD-L1 blocking antibodies.

Very common (10% or more): Hypothyroidism (includes hypothyroidism, increased blood thyroid stimulating hormone [TSH], immune-mediated hypothyroidism; up to 12%)

Common (1% to 10%): Hyperthyroidism, increased blood TSH, decreased blood TSH

Uncommon (0.1% to 1%): Adrenal insufficiency, hypophysitis (includes hypophysitis, lymphocytic hypophysitis), thyroiditis (includes thyroiditis, autoimmune thyroiditis)

Frequency not reported: Hypoparathyroidism

Gastrointestinal

Immune-mediated diarrhea or colitis occurred in 2% (25/1281) of patients receiving this drug, including grade 2 (0.9%) and grade 3 (0.8%) adverse reactions. Diarrhea or colitis led to permanent discontinuation of this drug in 0.4% of patients and withholding of therapy in 1.2% of patients. Among the 25 patients with immune-mediated diarrhea or colitis, the median time to onset was 3.8 months (range: 1 day to 16.6 months) and the median duration of immune-mediated diarrhea or colitis was 2.1 months (range: 4 days to 26.8 months). Systemic corticosteroids were required in all patients with colitis, which resolved in 56% of the 25 patients. This drug was withheld in 16 patients, with 6 restarting therapy after symptom improvement; of these 6 patients, 4 had recurrence of colitis.

Clinically significant immune-mediated gastrointestinal adverse reactions (including pancreatitis [to include increases in serum amylase and lipase levels], gastritis/immune-mediated gastritis, duodenitis, stomatitis) occurred at an incidence of less than 1% in patients who received this drug or were reported with the use of other PD-1/PD-L1 blocking antibodies.

Very common (10% or more): Diarrhea (includes diarrhea, colitis, autoimmune colitis, enterocolitis; up to 33%), nausea (up to 25%), constipation (up to 14%), vomiting (includes hematemesis, vomiting; up to 12.2%), abdominal pain (includes abdominal pain, upper abdominal pain, lower abdominal pain, gastrointestinal pain, abdominal distension, abdominal discomfort; up to 12%)

Common (1% to 10%): Immune-mediated colitis, colitis (includes colitis, autoimmune colitis, enterocolitis, immune-mediated enterocolitis), stomatitis

Uncommon (0.1% to 1%): Mesenteric artery thrombosis, gastritis (includes gastritis, immune-mediated gastritis)

Frequency not reported: Pancreatitis (includes increased serum amylase levels, increased serum lipase levels), duodenitis

Genitourinary

Very common (10% or more): Urinary tract infection (includes urinary tract infection, cystitis, urosepsis, pyelonephritis, kidney infection, acute pyelonephritis, bacterial cystitis, Escherichia urinary tract infection, pyelocystitis, bacterial urinary tract infection, pseudomonal urinary tract infection; up to 13%)

Frequency not reported: Noninfective cystitis

Hematologic

Very common (10% or more): Anemia (up to 43.6%), hemorrhage (includes tumor hemorrhage, hematuria, epistaxis, eye hemorrhage, hemoptysis, intracranial hemorrhage, hemorrhagic diathesis, postmenopausal hemorrhage, rectal hemorrhage, skin hemorrhage, skin neoplasm bleeding, ulcer hemorrhage, vaginal hemorrhage, wound hemorrhage, subcutaneous hematoma; up to 18%), neutropenia (up to 15.4%), thrombocytopenia (includes thrombocytopenia, immune thrombocytopenia; up to 13.1%), decreased neutrophil count (grade 3 to 4; 10%)

Common (1% to 10%): Lymphopenia, increased INR, prolonged activated partial thromboplastin time, leukopenia, decreased lymphocyte count, decreased WBC count, decreased platelet count

Frequency not reported: Hemolytic anemia, aplastic anemia, immune thrombocytopenia

Postmarketing reports: Hemophagocytic lymphohistiocytosis

Clinically significant immune-mediated hematologic adverse reactions (including hemolytic anemia, aplastic anemia, immune thrombocytopenia) occurred at an incidence of less than 1% in patients who received this drug or were reported with the use of other PD-1/PD-L1 blocking antibodies.

Hepatic

Immune-mediated hepatitis occurred in 2.4% (31/1281) of patients receiving this drug, including grade 2 (0.2%), grade 3 (1.6%), grade 4 (0.3%), and fatal (less than 0.1%) adverse reactions. Hepatitis led to permanent discontinuation of this drug in 1.4% of patients and withholding of therapy in 0.7% of patients. Among the 31 patients with immune-mediated hepatitis, the median time to onset was 2.8 months (range: 7 days to 22.5 months) and the median duration of hepatitis was 2.3 months (range: 5 days to 8.7 months). Systemic corticosteroids were required in all patients with hepatitis, and 4 patients required additional immunosuppression with mycophenolate; hepatitis resolved in 39% of the 31 patients. This drug was withheld in 9 patients, with 5 patients restarting therapy after symptom improvement; of these 5 patients, 1 had recurrence of hepatitis.

Very common (10% or more): Increased ALT (up to 16.3%), increased AST (up to 14.7%), liver function test abnormalities (includes increased ALT, increased AST, increased conjugated bilirubin, increased blood alkaline phosphatase, increased blood bilirubin, increased GGT; 10%)

Common (1% to 10%): Immune-mediated hepatitis, increased blood bilirubin, hepatitis (includes autoimmune hepatitis, immune-mediated hepatitis, hepatitis, hepatotoxicity, hyperbilirubinemia, hepatocellular injury, hepatic failure, abnormal hepatic function)

Uncommon (0.1% to 1%): Acute hepatitis, increased transaminases, increased GGT

Immunologic

Very common (10% or more): Immune-mediated adverse reactions (including hypothyroidism, hyperthyroidism, immune-mediated pneumonitis, immune-mediated hepatitis, immune-mediated colitis, immune-mediated skin adverse reactions; up to 21%)

Common (1% to 10%): Antidrug antibodies

Frequency not reported: Hemophagocytic lymphohistiocytosis, systemic inflammatory response syndrome, histiocytic necrotizing lymphadenitis (Kikuchi lymphadenitis), sarcoidosis

Postmarketing reports: Solid organ transplant rejection

Immune-mediated adverse reactions have occurred in various organ systems and tissues and have affected more than 1 body system simultaneously. Severe or fatal cases have been reported for some of these adverse reactions.

Immune-mediated adverse reactions occurred in up to 21% of patients treated with this drug in clinical trials, including grade 2 (up to 11.2%), grade 3 (up to 5.7%), grade 4 (up to 0.6%), and grade 5 (up to 0.4%). Immune-mediated adverse reactions led to permanent discontinuation of this drug in up to 4.6% of patients. The most common immune-mediated adverse reactions were hypothyroidism, hyperthyroidism, immune-mediated pneumonitis, immune-mediated hepatitis, immune-mediated colitis, and immune-mediated skin adverse reactions.

Clinically significant immune-mediated immunologic adverse reactions (including hemophagocytic lymphohistiocytosis, systemic inflammatory response syndrome, histiocytic necrotizing lymphadenitis [Kikuchi lymphadenitis], sarcoidosis, solid organ transplant rejection) occurred at an incidence of less than 1% in patients who received this drug or were reported with the use of other PD-1/PD-L1 blocking antibodies.

Metabolic

Very common (10% or more): Hyperglycemia (up to 17.6%), decreased appetite (up to 17%), hypoalbuminemia (up to 10.3%)

Common (1% to 10%): Hyponatremia, hypophosphatemia, hypercalcemia, hypokalemia, hyperkalemia, hypocalcemia, hypermagnesemia, hypernatremia

Uncommon (0.1% to 1%): Cachexia worsening (due to colitis), type 1 diabetes mellitus (includes diabetic ketoacidosis, type 1 diabetes mellitus, diabetes mellitus)

Musculoskeletal

Clinically significant immune-mediated musculoskeletal and connective tissue adverse reactions (including myositis/polymyositis/dermatomyositis, rhabdomyolysis [and associated sequelae, including renal failure], arthritis, polymyalgia rheumatica, arthralgia, muscular weakness, myalgia, Sjogren's syndrome) occurred at an incidence of less than 1% in patients who received this drug or were reported with the use of other PD-1/PD-L1 blocking antibodies.

Very common (10% or more): Musculoskeletal pain (includes arthralgia, back pain, myalgia, polyarthritis, pain in extremity, neck pain, noncardiac chest pain, arthritis, musculoskeletal chest pain, musculoskeletal pain, musculoskeletal stiffness, bone pain, immune-mediated arthritis, spinal pain, musculoskeletal discomfort; up to 36%)

Common (1% to 10%): Arthritis (includes arthritis, polyarthritis, immune-mediated arthritis)

Uncommon (0.1% to 1%): Sjogren's syndrome, myositis (includes myositis, dermatomyositis), muscular weakness, polymyalgia rheumatica

Frequency not reported: Polymyositis, dermatomyositis, rhabdomyolysis (with associated sequelae [including renal failure])

Nervous system

Clinically significant immune-mediated nervous system adverse reactions (including meningitis, encephalitis, myelitis, demyelination, myasthenic syndrome/myasthenia gravis [including exacerbation], Guillain-Barre syndrome, nerve paresis, autoimmune neuropathy, aseptic meningitis, paraneoplastic encephalomyelitis, chronic inflammatory demyelinating polyradiculoneuropathy, peripheral neuropathy, central nervous system inflammation) occurred at an incidence of less than 1% in patients who received this drug or were reported with the use of other PD-1/PD-L1 blocking antibodies.

Very common (10% or more): Peripheral neuropathy (includes peripheral neuropathy, paresthesia, dysesthesia, hypoesthesia, peripheral motor neuropathy, burning sensation, neuralgia, peripheral sensory neuropathy, polyneuropathy, peripheral sensorimotor neuropathy, polyneuropathy in malignant disease, toxic neuropathy, neuritis; up to 23%), headache (includes headache, sinus headache, migraine; up to 13%), dizziness (includes dizziness, vertigo, positional vertigo, postural dizziness; up to 12%)

Frequency not reported: Meningitis (includes aseptic meningitis), encephalitis, myelitis, demyelination, myasthenic syndrome/myasthenia gravis (including exacerbation), Guillain-Barre syndrome, nerve paresis, autoimmune neuropathy, ischemic stroke, paraneoplastic encephalomyelitis, chronic inflammatory demyelinating polyradiculoneuropathy

Ocular

Clinically significant immune-mediated ocular adverse reactions (including uveitis, iritis, other ocular inflammatory toxicities, keratitis) occurred at an incidence of less than 1% in patients who received this drug or were reported with the use of other PD-1/PD-L1 blocking antibodies. Some cases were associated with retinal detachment, and various grades of visual impairment (including blindness) have occurred.

Common (1% to 10%): Visual impairment

Frequency not reported: Uveitis, iritis, other ocular inflammatory toxicities, retinal detachment, visual impairment (various grades, including blindness), Vogt-Koyanagi-Harada-like syndrome, keratitis

Other

Infusion-related reactions occurred in 7.3% (94/1281) of patients receiving this drug, including 0.2% of patients with grade 3 or 4 adverse reactions. Common symptoms of infusion-related reaction included nausea, pyrexia, and vomiting. Infusion-related reaction led to permanent discontinuation of this drug in 1 patient. At time of data cutoff, 98.9% of the 94 patients recovered from the infusion-related reaction.

Very common (10% or more): Fatigue (includes fatigue, asthenia, malaise; up to 50%), decreased weight (up to 11.2%), edema (includes peripheral edema, peripheral swelling, face swelling, face edema, localized edema, generalized edema, swelling; 10%)

Common (1% to 10%): Infusion-related reaction, increased blood alkaline phosphatase, pyrexia (includes pyrexia, hyperthermia, hyperpyrexia), deaths due to infections, death not otherwise specified, sudden death

Frequency not reported: General physical health deterioration, fall

Psychiatric

Very common (10% or more): Insomnia (up to 11%)

Frequency not reported: Confusional state

Renal

Very common (10% or more): Acute kidney injury (includes increased blood creatinine, acute kidney injury, renal failure, renal impairment, decreased glomerular filtration rate, toxic nephropathy; up to 14%)

Common (1% to 10%): Increased blood creatinine, nephritis (includes acute kidney injury, nephritis, renal failure, toxic nephropathy, renal impairment, immune-mediated nephritis, tubulointerstitial nephritis)

Uncommon (0.1% to 1%): Immune-mediated nephritis

Immune-mediated nephritis occurred in 0.7% (9/1281) of patients receiving this drug, including grade 2 (0.5%), grade 3 (less than 0.1%), and fatal (less than 0.1%) adverse reactions. Nephritis led to permanent discontinuation of this drug in 0.2% of patients and withholding of therapy in 0.4% of patients. Among the 9 patients with immune-mediated nephritis, the median time to onset was 2.1 months (range: 14 days to 12.5 months) and the median duration of nephritis was 1.5 months (range: 9 days to 5.5 months). Systemic corticosteroids were required in all patients with nephritis, which resolved in 78% of the 9 patients. This drug was withheld in 5 patients, with 4 restarting therapy after symptom improvement; of these 4 patients, 1 had recurrence of nephritis.

Respiratory

Very common (10% or more): Upper respiratory tract infection (includes upper respiratory tract infection, nasopharyngitis, sinusitis, influenza-like illness, rhinitis, influenza, viral upper respiratory tract infection, respiratory tract infection, influenza A virus test positive, pharyngitis, viral rhinitis, laryngitis, viral respiratory tract infection, acute sinusitis, tonsillitis, tracheitis; up to 22%), dyspnea (includes dyspnea, exertional dyspnea; up to 14%), cough (includes cough, productive cough, upper airway cough syndrome; up to 12%), pneumonia (includes atypical pneumonia, embolic pneumonia, lower respiratory tract infection, lung abscess, paracancerous pneumonia, pneumonia, bacterial pneumonia, Klebsiella pneumonia; up to 11%)

Common (1% to 10%): Immune-mediated pneumonitis, pneumonitis (includes pneumonitis, immune-mediated lung disease, interstitial lung disease, pulmonary fibrosis)

Uncommon (0.1% to 1%): Acute respiratory distress syndrome, pulmonary hemorrhage

Frequency not reported: Coronavirus disease 2019 (COVID-19) infection

Immune-mediated pneumonitis occurred in 2.6% (33/1281) of patients receiving this drug, including grade 2 (1.6%), grade 3 (0.6%), and grade 4 (0.3%) adverse reactions. Pneumonitis led to permanent discontinuation of this drug in 1.3% of patients and withholding of therapy in 1.4% of patients. Among the 33 patients with immune-mediated pneumonitis, the median time to onset was 2.7 months (range: 7 days to 22.2 months) and the median duration of pneumonitis was 1.1 months (range: 5 days to 16.9 months). Systemic corticosteroids were required in all patients with pneumonitis, which resolved in 61% of the 33 patients. This drug was withheld in 18 patients, with 10 patients restarting therapy after symptom improvement; of these 10 patients, 4 had recurrence of pneumonitis.

Frequently asked questions

References

1. Product Information. Libtayo (cemiplimab). Regeneron Pharmaceuticals Inc. 2023;SUPPL-16.

2. Product Information. Libtayo (cemiplimab). Sanofi-Aventis Australia Pty Ltd. 2023;lib-ccdsv7-piv4-05ju.

3. Product Information. Libtayo (cemiplimab). Sanofi. 2023.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

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