cemiplimab: clinical use

Prescribing considerations

• Confirm that tumour type, disease setting, prior therapy and, for NSCLC, validated PD-L1 and genomic criteria match the licensed indication.
• Treatment should be initiated and supervised by clinicians experienced in cancer treatment.
• Review autoimmune disease, prior pneumonitis or interstitial lung disease, active infection, immunocompromise and transplant history.
• Provide the patient alert card and explain that immune toxicity may affect multiple organs and occur after discontinuation.
• Avoid routine dose reduction; manage toxicity through interruption, discontinuation and appropriate treatment according to severity.

Contraindications and cautions

• Hypersensitivity to cemiplimab or any excipient.
• Use particular caution with pre-existing autoimmune disease, solid-organ transplant, allogeneic stem-cell transplant history, severe hepatic impairment, active infection or previous interstitial lung disease.
• Polysorbate 80 may cause allergic reactions; L-proline may be harmful in hyperprolinaemia.

Monitoring

• Assess for immune-mediated toxicity at baseline, throughout treatment and after discontinuation.
• Monitor liver and renal function, thyroid function and blood glucose; investigate possible pituitary, adrenal or other endocrine dysfunction.
• Monitor respiratory, gastrointestinal, dermatological, neurological, cardiac and ocular symptoms.
• Observe for infusion reactions and record the product name and batch number.
• When combined with chemotherapy, follow each chemotherapy component's monitoring requirements.

Clinical pharmacology

Cemiplimab is a fully human IgG4 monoclonal antibody that blocks PD-1 interaction with PD-L1 and PD-L2. It is expected to be broken down into peptides and amino acids rather than cleared through conventional hepatic metabolism; its steady-state half-life is approximately 22 days.

Formulation and product differences

• The selected product is a single-use sterile concentrate requiring dilution before intravenous infusion.
• It is a clear to slightly opalescent, colourless to pale-yellow solution requiring refrigerated, light-protected storage before use.
• It contains L-proline and polysorbate 80. No alternative cemiplimab formulation is represented by the selected UK product.

Solution for infusion

Route: Intravenous

Strengths: 350 mg