OBJECTIVES:
Primary
* Compare the efficacy of standard antiemetic therapy comprising ondansetron and dexamethasone combined with either aprepitant or placebo in controlling nausea and vomiting, as determined by the number of retch/emesis-free days, in patients undergoing hematopoietic stem cell transplantation.
Secondary
* Determine the safety of aprepitant in these patients.
* Compare nausea, appetite, taste changes, nutritional intake, and mucositis in patients treated with these regimens.
* Determine the pharmacokinetics of cyclophosphamide, carboxyethylphosphoramide mustard, hydroxycyclophylamide, and aprepitant in these patients.
OUTLINE: This is a randomized, placebo-controlled, single-blind, pilot study. Patients are randomized to 1 of 2 treatment arms.
* Arm I: Beginning on the first day of conditioning chemotherapy, patients receive oral aprepitant once daily and standard antiemetic therapy comprising oral or IV ondansetron and oral dexamethasone.
* Arm II: Patients receive oral placebo once daily and standard antiemetic therapy as in arm I.
In both arms, treatment continues until day 4 after stem cell transplant in the absence of unacceptable toxicity.
After completion of study therapy, patients are followed until day 18.
PROJECTED ACCRUAL: A total of 40 patients (20 per treatment arm) will be accrued for this study.
