Loncastuximab tesirine (Specialist drug)

NO UK SPC WAS AVAILABLE IN THE FETCHED BUNDLE — dose taken from the US prescribing information (ZYNLONTA, ADC Therapeutics America, label date 2026-06-12). US §2.1: 'ZYNLONTA as an intravenous infusion administered over 30 minutes on Day 1 of each cycle (every 3 weeks)... 0.15 mg/kg every 3 weeks for 2 cycles. 0.075 mg/kg every 3 weeks for subsequent cycles.' PREMEDICATION (§2.2): unless contraindicated, give dexamethasone 4 mg orally or intravenously twice daily for 3 days beginning the day before loncastuximab tesirine; if it does not begin the day before, dexamethasone should start at least 2 hours before the infusion. DOSE CALCULATION (§2.4): for patients with a body mass index >=35 kg/m2, calculate the dose using an adjusted body weight, ABW in kg = 35 kg/m2 x (height in metres)^2. Reconstitute each 10 mg vial with 2.2 mL Sterile Water for Injection to 5 mg/mL, then dilute the calculated dose volume into a 50 mL bag of 5% dextrose injection; do not shake. Administer via a dedicated infusion line with a sterile, non-pyrogenic, low-protein-binding in-line or add-on 0.2- or 0.22-micron filter. Do not mix with, or infuse alongside, other drugs. Extravasation has been associated with irritation, swelling, pain and/or tissue damage, which may be severe — monitor the infusion site. DOSE MODIFICATION (§2.3): withhold for absolute neutrophil count <1 x 10^9/L until it returns to >=1 x 10^9/L; withhold for platelets <50,000/mcL until >=50,000/mcL; withhold for Grade 2 or higher edema or effusion until resolved to Grade 1 or less; withhold for Grade 2 pericardial effusion until resolved and discontinue if it recurs, discontinue for Grade 3 or higher pericardial effusion; withhold for Grade 3 or higher AST/ALT rise or suspected drug-induced liver injury until Grade 1 or less and discontinue for confirmed DILI; withhold other Grade 3 or higher reactions until Grade 1 or less. If dosing is delayed by more than 3 weeks because of drug-related toxicity, reduce subsequent doses by 50%; if toxicity recurs after reduction, consider discontinuation. If toxicity requires dose reduction after the second 0.15 mg/kg dose (Cycle 2), the patient should receive 0.075 mg/kg for Cycle 3. PAEDIATRIC: 'Safety and effectiveness of ZYNLONTA in pediatric patients have not been established' (§8.4) — hence paedDose is null. ELDERLY (§8.5): no overall differences in safety or effectiveness were observed between patients 65 years and older and younger patients. Clinician to confirm the UK licensed posology and indication against the current SPC before publication.