RATIONALE: Acyclovir may be effective in preventing herpes simplex virus infection in patients with neutropenia.

PURPOSE: This randomized phase III trial is studying the side effects of acyclovir and is comparing two doses of acyclovir in preventing herpes simplex virus infection in patients with neutropenia.

OBJECTIVES:

• To determine the difference in nephrotoxicity between low-dose and weight-based intravenous acyclovir sodium as herpes simplex virus infection prophylaxis in patients with neutropenia.

OUTLINE: Patients are randomized to 1 of 2 treatment arms.

• Arm I: Patients receive weight-based IV acyclovir sodium every 8 or 12 hours.
• Arm II: Patients receive low-dose IV acyclovir sodium every 8 or 12 hours. Treatment continues for approximately 2 weeks unless clinical herpes simplex virus infection is confirmed or the patient is no longer neutropenic.

Inclusion Criteria:

• Be 18 years of age or older.
• Receiving treatment in inpatient oncology services at Wake Forest University Baptist Medical Center
• Receiving chemotherapy or have received chemotherapy within the past 2 weeks
• Seropositive herpes simplex virus (HSV)-1 or HSV-2 immunoglobulin antibody assay
• Creatinine clearance ≥ 50 mL/min
• Intravenous acyclovir sodium therapy is deemed necessary by the physician based upon clinical judgement (i.e., mucositis, vomiting, decreased GI absorption)

Exclusion Criteria:

• Pregnant or nursing
• Hypersensitivity to acyclovir sodium
• High tumor burden (i.e., WBC > 50,000/mm^3 at admission)
• Neutropenic, defined as one of the following:
• ANC < 500/mm^3
• ANC < 1,000/mm^3 with a predicted decrease to 500/mm^3
• Active HSV infection, as evidenced by any of the following:
• Positive HSV cultures
• Oral lesions
• Receiving 5 mg/kg acyclovir sodium every 8 hours

per the protocol, only nephrotoxicities (as measured by Creatinine increase over baseline were observed.