polatuzumab vedotin: clinical use

Prescribing considerations

• Treatment requires supervision by a clinician experienced in cancer care and use with the appropriate licensed combination medicines.
• Give antihistamine and antipyretic premedication if not already administered.
• Consider G-CSF and anti-infective prophylaxis according to clinical risk and local policy.
• Assess pre-existing neuropathy, infection, hepatic impairment, tumour burden and medicines affecting CYP3A4 or P-glycoprotein.
• Avoid administration in moderate or severe hepatic impairment because unconjugated MMAE exposure may increase.
• Record the product name and batch number for biological traceability.

Contraindications and cautions

• Hypersensitivity to polatuzumab vedotin or an excipient
• Active severe infection

Monitoring

• Full blood count before each administration and more frequently when clinically indicated
• New or worsening sensory, motor or gait symptoms
• Bacterial, viral, fungal and opportunistic infection
• Infusion and delayed hypersensitivity reactions
• Liver enzymes and bilirubin
• Tumour lysis risk in patients with bulky or rapidly proliferating disease
• Neurological, cognitive or behavioural changes suggesting PML
• Venous access and signs of extravasation

Clinical pharmacology

Polatuzumab vedotin is a CD79b-directed humanised IgG1 antibody–drug conjugate linked to MMAE. Internalisation and lysosomal cleavage release MMAE, which inhibits microtubule function and induces apoptosis. Unconjugated MMAE is affected by CYP3A4 and P-glycoprotein activity.

Formulation and product differences

• Supplied as a white to greyish-white powder for concentrate in two single-use vial strengths.
• Both presentations contain the same active ingredient and excipients and produce the same concentration after reconstitution.
• The formulation contains polysorbate 20 and is essentially sodium-free.

Solution for infusion

Route: Intravenous

Strengths: 30 mg, 140 mg