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cemiplimab

Libtayo · ATC code L01XC33

Also known as: Semiplimab

Key facts
Active substance
cemiplimab
ATC code
L01XC33
Authorisation
centrally authorised across the EU (EMA)
Dosage forms
LIBTAYO 350 mg concentrate for solution for infusion.
Marketing authorisation holder
Regeneron Ireland Designated Activity Company (DAC)
Information as of
2026-10-28

Key facts

Cemiplimab (Libtayo) is a monoclonal antibody against PD-1 (an immune checkpoint inhibitor) given by infusion for several advanced cancers.

What it is used for

  • Cutaneous squamous cell carcinoma: metastatic or locally advanced and not candidates for curative surgery or radiation; adjuvant treatment at high risk of recurrence after surgery and radiation.
  • Locally advanced or metastatic basal cell carcinoma after progression on or intolerance to a hedgehog pathway inhibitor.
  • Non-small cell lung cancer (NSCLC) without EGFR, ALK or ROS1 aberrations, first line: as monotherapy with PD-L1 in ≥ 50% of tumour cells; with platinum-based chemotherapy with PD-L1 in ≥ 1%.
  • Recurrent or metastatic cervical cancer with progression on or after platinum-based chemotherapy.

Dosing

  • Advanced CSCC, NSCLC, BCC and cervical cancer: 350 mg every 3 weeks as a 30-minute intravenous infusion until progression or unacceptable toxicity.
  • Adjuvant treatment of high-risk CSCC: 350 mg every 3 weeks for 12 weeks followed by 700 mg every 6 weeks, or 350 mg every 3 weeks; up to 48 weeks in total.
  • No dose reductions; dosing delay or discontinuation according to adverse reaction severity (see the full text).
  • Initiated and supervised by physicians experienced in cancer treatment; NSCLC requires PD-L1 testing with a validated test.

Contraindications

  • Hypersensitivity to the active substance or any excipient.

Important warnings

  • Severe and fatal immune-mediated adverse reactions (e.g. pneumonitis, colitis, hepatitis, endocrinopathies, skin reactions) may involve any organ, also after discontinuation; managed with withholding, corticosteroids or hormone replacement.
  • Reactions affecting several organs at once, such as myositis with myocarditis or myasthenia gravis, can occur.
  • Severe or life-threatening infusion-related reactions can occur.
  • Severe cutaneous adverse reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis) and haemophagocytic lymphohistiocytosis have been reported.

Side effects

  • Immune-mediated adverse reactions in 21% of patients on monotherapy; most common hypothyroidism (6.8%), hyperthyroidism (3.0%), pneumonitis (2.6%), hepatitis (2.4%), colitis (2.0%) and skin reactions (1.9%).
  • Adverse events were serious in 32.4% of patients on monotherapy and led to permanent discontinuation in 9.4%.

Interactions

  • Systemic corticosteroids or immunosuppressants before starting (except physiological doses ≤ 10 mg/day prednisone) should be avoided; they can be used after starting to treat immune-mediated reactions.

Pregnancy and breastfeeding

  • Not recommended during pregnancy unless the benefit outweighs the risk; women of childbearing potential should use contraception for at least 4 months after the last dose.
  • Do not breast-feed during treatment and for at least 4 months after the last dose.

Summary of the official product information, written with AI on 2026-10-29. Every number was checked automatically against the original text. Not reviewed by a physician – the full official text is authoritative.

Full official text →

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For patients

Package leaflet, verbatim

This product has no separate US patient information.

Authorisation and brand names by country

Medicines with exactly this active-substance composition, as listed in the national registers – alphabetical and without ranking. Whether a product is currently available is not shown here.

EU – centrally authorised (all member states)

  • LibtayoRegeneron Ireland Designated Activity Company (DAC) · EMEA/H/C/004844

Source: European Medicines Agency (EMA), product information

Brand names in 3 more European countries
Iceland
Libtayo
Liechtenstein
Libtayo
Norway
Libtayo

EMA – Article 57 product data (EU/EEA), 2026-10-29

Medelix receives no money from pharmaceutical companies. Brand names are listed alphabetically and without ranking.

Other substances in the same group

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Medelix answers clinical questions from guidelines, studies and product information – every claim with its source.

Sources

  1. European Medicines Agency. Libtayo – EPAR, Product Information. 2026-10-28. https://www.ema.europa.eu/en/documents/product-information/libtayo-epar-product-information_en.pdf

Editorial: Medelix editorial team · last updated 2026-10-28 · How these pages are made · Report an error

Source: European Medicines Agency (EMA), product information. Not advertising, not a treatment recommendation. For questions about your own treatment, ask your doctor or pharmacist.