A retrospective study was performed to collect information regarding efficacy and toxicity of
cidofovir (CDV) in allogeneic stem cell transplant patients. Data were available on 82 patients. The indications for
therapy were cytomegalovirus (CMV) disease in 20 patients, primary preemptive
therapy in 24 patients, and secondary preemptive
therapy in 38 patients. Of the patients, 47 had received previous
antiviral therapy with
ganciclovir,
foscarnet, or both drugs. The dosage of CDV was 1 to 5 mg/kg per week followed by maintenance every other week in some patients. The
duration of therapy ranged from 1 to 134 days (median, 22 days). All patients received
probenecid and prehydration. Ten of 20 (50%) patients who were treated for CMV disease (9 of 16 with
pneumonia) responded to CDV
therapy, as did 25 of 38 (66%) patients who had failed or relapsed after previous preemptive
therapy and 15 of 24 (62%) patients in whom CDV was used as the primary preemptive
therapy. Of the patients, 21 (25.6%) developed renal toxicity that remained after cessation of
therapy in 12 patients. Fifteen patients developed other toxicities that were potentially due to CDV or the concomitantly given
probenecid. No toxicity was seen in 45 (61.6%) patients.
Cidofovir can be considered as second-line
therapy in patients with CMV disease failing previous
antiviral therapy. However, additional studies are needed before CDV can be recommended for preemptive
therapy.