Valganciclovir to Prevent Cytomegalovirus Infection in Patients Following Donor Stem Cell Transplantation

DISEASE CHARACTERISTICS: Have undergone allogeneic peripheral blood stem cell, cord blood, or marrow transplantation (related or unrelated, T-cell depleted or non-T-cell depleted, CD34-selected or non-selected, or myeloablative or non-myeloablative) within the past 80-120 days Positive pre-transplantation cytomegalovirus (CMV) serology of recipient and/or donor Seropositive recipients with one of the following: CMV infection before day 80, as determined by: pp65 antigenemia CMV DNA in plasma Peripheral blood leukocytes (PBL) or whole blood at any level detected by polymerase chain reaction or hybrid capture CMV pp67 mRNA CMV viremia by blood culture Surveillance bronchoalveolar lavage (culture or cytology) CMV disease more than 6 weeks prior to enrollment Presence of graft-versus-host disease (GVHD) at enrollment Acute GVHD that requires treatment with systemic corticosteroids of doses greater than 0.5 mg/kg OR Chronic clinically extensive GVHD requiring treatment with corticosteroids Continuous prophylaxis with ganciclovir, foscarnet, or cidofovir between engraftment and day 80 OR Seronegative recipient with seropositive donor who has CMV infection before day 80 No rising or uncontrolled CMV load (pp65 antigenemia levels no greater than 1/slide or no greater than 100 copies of CMV DNA per mL of plasma or per million PBL allowed) No CMV disease within 6 weeks prior to randomization No leukemic relapse Cytogenetic or molecular relapse allowed PATIENT CHARACTERISTICS: Age: 16 and over Performance status: Not specified Life expectancy: At least 2 weeks Hematopoietic: Absolute neutrophil count at least 1,000/mm^3 for at least 1 week prior to enrollment Hepatic: Not specified Renal: Creatinine no greater than 2.5 mg/mL Other: No hypersensitivity to ganciclovir or valganciclovir No uncontrolled diarrhea or severe gastrointestinal disease that would preclude oral medication Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for 90 days after study participation HIV negative Proficient in English PRIOR CONCURRENT THERAPY: Biologic therapy: See Disease Characteristics Chemotherapy: Not specified Endocrine therapy: See Disease Characteristics Radiotherapy: Not specified Surgery: Not specified Other: Prior ganciclovir, foscarnet, cidofovir, high-dose acyclovir, or valacyclovir as prophylaxis or preemptive therapy allowed No concurrent prophylactic foscarnet, cidofovir, or ganciclovir (IV or oral) No concurrent prophylactic high-dose acyclovir (more than 800 mg twice daily), valacyclovir (more than 500 mg twice daily), cidofovir (more than 0.5 mg/kg per week), or famciclovir (more than 500 mg/day) except for limited treatment courses at higher doses for varicella-zoster virus infections Concurrent low-dose (≤ 0.5 mg/kg per week) cidofovir allowed for limited treatment courses