Valganciclovir

⚠ THIS DRAFT REPLACES AN EARLIER US-ONLY DRAFT. VERBATIM §4.2: 'Caution – Strict adherence to dosage recommendations is essential to avoid overdose.' 'Oral valganciclovir 900 mg b.i.d. is therapeutically equivalent to intravenous ganciclovir 5 mg/kg b.i.d.' Induction: 'For patients with active CMV retinitis, the recommended dose is 900 mg valganciclovir (two Valcyte 450 mg tablets) twice a day for 21 days and, whenever possible, taken with food.' Maintenance: 'Following induction treatment, or in patients with inactive CMV retinitis, the recommended dose is 900mg valganciclovir (two Valcyte 450 mg tablets) once daily and, whenever possible, taken with food. Patients whose retinitis worsens may repeat induction treatment; however, consideration should be given to the possibility of viral drug resistance.' Transplant prophylaxis: 'For kidney transplant patients, the recommended dose is 900 mg (two Valcyte 450 mg tablets) once daily, starting within 10 days post-transplantation and continuing until 100 days post-transplantation. Prophylaxis may be continued until 200 days post-transplantation.' 'For patients who have received a solid organ transplant other than kidney, the recommended dose is 900 mg (two Valcyte 450 mg tablets) once daily, starting within 10 days post-transplantation and continuing until 100 days post-transplantation.' This §4.2 is COMPLETE in the bundle (no truncation marker) and covers both halves of this page's stated identity — CMV prevention AND treatment, oral. §4.4 and §4.8 ARE truncated, so the warnings and adverse-effect lists below are partial. ELDERLY, VERBATIM: 'Safety and efficacy have not been established in this patient population. No studies have been conducted in adults older than 65 years of age. Since renal clearance decreases with age, Valcyte should be administered to elderly patients with special consideration of their renal status.' HEPATIC IMPAIRMENT: 'Safety and efficacy of Valcyte tablets have not been established in patients with hepatic impairment.' HAEMODIALYSIS: 'For patients on haemodialysis (Clcr < 10 ml/min) a dose recommendation cannot be given. Thus Valcyte film-coated tablets should not be used in these patients.' HANDLING: 'Since Valcyte is considered a potential teratogen and carcinogen in humans, caution should be observed in handling broken tablets. Avoid direct contact of broken or crushed tablets with skin or mucous membranes.'

⚠ dosePerKg IS NULL DELIBERATELY AND MUST STAY NULL — the paediatric dose is NOT weight-based. It is calculated from body surface area AND renal function, so a per-kilogram calculator would produce a wrong dose. INDICATION: prevention of CMV disease in paediatric solid organ transplant patients only. VERBATIM §4.2: 'In paediatric solid organ transplant patients, aged from birth, who are at risk of developing CMV disease, the recommended once daily dose of Valcyte is based on body surface area (BSA) and creatinine clearance (Clcr) derived from Schwartz formula (ClcrS), and is calculated using the equation below: Paediatric Dose (mg) = 7 x BSA x ClcrS.' 'If the calculated Schwartz creatinine clearance exceeds 150 mL/min/1.73m2, then a maximum value of 150 mL/min/1.73m2 should be used in the equation.' Schwartz k values, verbatim: 'k = 0.45* for patients aged < 2 years, 0.55 for boys aged 2 to < 13 years and girls aged 2 to 16 years, and 0.7 for boys aged 13 to 16 years. Refer to adult dosing for patients older than 16 years of age. The k values provided are based on the Jaffe method of measuring serum creatinine and may require correction when enzymatic methods are used. *For appropriate sub-populations a lowering of k value may also be necessary (e.g. in paediatric patients with low birth weight).' ROUNDING, VERBATIM: 'All calculated doses should be rounded to the nearest 25 mg increment for the actual deliverable dose.' ⚠ NOTE THE UK/US DIFFERENCE: the previous draft of this page carried 'round to the nearest 10 mg' and age ranges of 4 months–16 years (kidney) and 1 month–16 years (heart), taken from the US oral-solution label. The UK SPC rounds to the nearest 25 mg and states 'aged from birth'. Use the UK figures on this UK page. CMV RETINITIS IN CHILDREN IS NOT ESTABLISHED, VERBATIM: 'The safety and efficacy of Valcyte in the treatment of CMV retinitis have not been established in adequate and well-controlled clinical studies in paediatric patients.' ONGOING ADJUSTMENT: 'It is recommended to monitor serum creatinine levels regularly and consider changes in height and body weight and adapt the dose as appropriate during the prophylaxis period.' concentration is null because the fetched UK product is a 450 mg TABLET — no oral-liquid mg/ml figure exists in this UK source (the US label in the bundle describes a 50 mg per mL oral solution, a different product and market). Verify any under-18 dose against a children's formulary. SUMMARY OF THE FORMULA: Paediatric Dose (mg) = 7 × BSA (Mosteller) × Schwartz creatinine clearance (ClcrS capped at 150 mL/min/1.73m²), rounded to the nearest 25 mg, maximum 900 mg, once daily.