[Evaluation of pharmacokinetics and safety of valganciclovir oral suspension treatment in pediatric kidney graft recipients--preliminary report].

BACKGROUND: Invasive CMV disease in transplanted organ recipients is a life threatening condition. CMV infection is also known risk factor for acute rejection and chronic allograft nephropathy. The risk of CMV infection in pediatric population is high, especially in terms of primary infection. It can be significantly reduced under long term (3 months) prophylaxis with ganciclovir (GCV), available exclusively as parenteral drug. Since recently oral tablet pro-drug valganciclovir (VCV, Valcyte, Roche) is given in adult patients. This drug has proved similar efficacy and good bioavailability (roughly 70%), however there is no registered liquid form which can be precisely and safety administered in small children. MATERIAL AND METHOD: 10 children after kidney transplantation, aged 2-9.5 year (mean 5.1; SD +/- 2.3), body weight 8.5-19.5 kg (mean 14.6; SD +/- 3.5), with good graft function (serum creatinine 0.3-0.8 mg/dl) were given VCV oral suspension prepared in hospital pharmacy, using Valcyte tablets and commercially available vehicle (Paddock Laboratories, Inc) (60 mg/ml), 7.5 mg/kg b.w., 2-3 x/day. Through level (CO) of GCV in blood was measured in all patient, in 4 patient drug kinetics (4 measurements) was also analyzed preceded with evaluation of GCV elimination after intravenous infusion of GCV. RESULTS: There was no episode of drug toxicity nor drug withdrawal from other reason. CO (mean = 0.74 microg/ml; max. 1.15; min. 0.38; SD +/- 0.25) was close to predefined values (0.4-1.0 microg/ml). Concentration profile of GCV (Cmax 1.0-1.5 h post dose) was similar to profile observed in adult patient treated with VCG tablets. CONCLUSION: Treatment with VCV suspension provides precise dosage and seems to be safe in patient with low body weight. It enables ambulatory prophylaxis and treatment of CMV infection.