Ganciclovir

Applies to adults and paediatric patients >=12 years of age with normal renal function (product: Ganciclovir 500 mg powder for solution for infusion, UK SPC). TREATMENT OF CMV DISEASE - induction 5 mg/kg IV over one hour every 12 hours for 14-21 days; maintenance (immunocompromised patients at risk of relapse) 5 mg/kg once daily on 7 days per week or 6 mg/kg once daily on 5 days per week, duration determined individually per local guidelines. Patients whose CMV disease progresses on maintenance or after withdrawal may be re-treated using the induction regimen. PREVENTION OF CMV DISEASE BY PRE-EMPTIVE THERAPY (adults and >=12 years) - induction 5 mg/kg every 12 hours for 7-14 days; maintenance 5 mg/kg once daily 7 days/week or 6 mg/kg once daily 5 days/week. UNIVERSAL PROPHYLAXIS (adults and patients >16 years) - 5 mg/kg once daily on 7 days per week or 6 mg/kg once daily on 5 days per week; duration based on the risk of CMV disease. ADMINISTRATION - must be given by intravenous infusion over 1 hour into a vein with adequate blood flow, preferably via a plastic cannula; do NOT give by rapid or bolus IV injection (excessive plasma levels increase toxicity) and do NOT give intramuscularly or subcutaneously (severe tissue irritation, solution pH ~11). The recommended dosage, frequency and infusion rates should not be exceeded. Ganciclovir is considered a potential teratogen and carcinogen in humans - handle with caution. Do not initiate if absolute neutrophil count <500 cells/microlitre, platelets <25,000 cells/microlitre or haemoglobin <8 g/dL; monitor full blood counts (white cell count every second day for the first 14 days, daily if baseline neutrophils <1,000/microlitre, previous leukopenia on myelotoxic therapy, or renal impairment). Elderly: no efficacy/safety studies; renal function declines with age - administer with special consideration of renal status. Hepatic impairment: safety and efficacy not studied. PAEDIATRICS - for treatment of CMV disease and pre-emptive therapy, the SPC states that for patients from birth to <12 years of age 'no recommendation on a posology can be made'. For universal prophylaxis from birth to <=16 years the once-daily IV dose is body-surface-area based, not per kg: paediatric dose (mg) = 3 x BSA (Mosteller) x CrCLS (Schwartz creatinine clearance), capping CrCLS at 150 mL/min/1.73m2 if the calculated value exceeds it; k = 0.33 for patients <1 year with low birth weight, 0.45 for patients <2 years, 0.55 for boys 2 to <13 years and girls 2 to 16 years, and 0.7 for boys 13 to 16 years (k values are based on the Jaffe method and may need correction with enzymatic assays). Review serum creatinine, height and weight regularly and amend the dose. Patients older than 16 years use adult dosing. Use warrants extreme caution in the paediatric population due to potential long-term carcinogenicity and reproductive toxicity - verify against a children's formulary.