Aprepitant's Effect on Drug Metabolism in Multi-Day Combination (CHOP/R-CHOP) Chemotherapy Regimen in Lymphoma Patients

The Study Drugs: Aprepitant is designed to block the natural substance in the brain that causes nausea and vomiting. This may help to prevent and/or control nausea and vomiting caused by cancer chemotherapy treatment. CHOP and R-CHOP are commonly used chemotherapy regimens for treating NHL. In the blood, aprepitant may increase or decrease the drug levels of cyclophosphamide, vincristine, and/or prednisone (which are part of the CHOP and R-CHOP regimens), but this is not known for certain. This study is designed to help researchers learn the effect of combining aprepitant with CHOP and R-CHOP. Study Groups: If you are found to be eligible to take part in this study, you will be randomly assigned (as in the toss of a coin) to 1 of 2 groups. There is an equal chance of being assigned to either group. Standard Chemotherapy Administration: Both CHOP and R-CHOP typically have 21-day "cycles" but can vary from every 14 to 28 days. You will receive CHOP or R-CHOP according to the schedule prescribed by your doctor. You will also receive standard medications for preventing nausea and vomiting. You will sign a separate consent form that will describe these treatments in detail, along with their risks. Aprepitant Administration: Aprepitant is taken by mouth, with or without food. Group 1 will take aprepitant on Days 1, 2, and 3 of Study Cycle 1 only. Group 2 will take aprepitant on Days 1, 2, and 3 of Study Cycle 2 only. Study Diary: Prior to each study cycle, you will be given a study diary to use throughout the study. Once a day, you will record any side effects you may have experienced. You should bring your study diary to every study visit so the study staff can review it. Study Visits: Prior to each study cycle, you will have a study visit with the following tests/procedures performed: * Your medical history will be recorded. * You will have a physical exam, including measurement of vital signs and weight. * You will have a performance status evaluation. * You will fill out the same questionnaire you did at screening, about any nausea and vomiting you may be experiencing. * You will be asked about any other medications you may be taking. Be sure to tell the study doctor about all medications (including vitamins, herbal products, and nutritional supplements), because some medications/substances will cause side effects when taken at the same time as aprepitant. * The study staff will review your study diary. Pharmacokinetic Testing: You will have additional blood samples drawn for pharmacokinetic (PK) testing of cyclophosphamide, vincristine, and prednisone levels. PK testing measures the amount of the drug in the body at different time points. These PK blood draws will be about 2 tablespoons each. On Days 1 and 2 of Study Cycles 1 and 2, blood will be drawn for PK testing at the following times: before taking prednisone, 30 minutes after the start of the cyclophosphamide infusion, and at 60 minutes, 75 minutes, 90 minutes, and 2, 4, 6, 8, and 24 hours after the start of the cyclophosphamide infusion. Other Blood Tests: At least twice a week during Study Cycles 1 and 2, blood (about 1 teaspoon) will be drawn for routine tests. Aprepitant may increase the blood sugar during the first few days the drug is taken. Because of this, on Day 1 of Study Cycle 1, you will be given a glucometer (a machine to check your blood sugar). You will use the glucometer at home during the study (or in the hospital if you are admitted there for chemotherapy). You will be given instructions on how to use it, and what to be looking for. On Days 1-6 of Study Cycle 1, you will give yourself a "fingerstick" blood sugar test once a day (before breakfast). You will take a "fingerstick" blood sugar test before you receive each dose of aprepitant. Length of Study: You may receive up to 2 cycles of chemotherapy, including 1 cycle of aprepitant. If intolerable side effects occur or the disease gets worse, you will be taken off study early. End-of-Study Visit: At 30 days after your last dose of aprepitant, you will return for an end-of-study visit. At this visit, you will have the same tests/procedures performed that you did at the other study visits. You will return the glucometer to the study staff. This is an investigational study. The CHOP and R-CHOP regimens are commercially available and FDA approved for use in NHL. Aprepitant is commercially available and FDA approved (when used in combination with other nausea medication, such as ondansetron) for the prevention of nausea and vomiting that may be caused by chemotherapy. However, this study is considered experimental because researchers want to find out how aprepitant may affect the drug levels of cyclophosphamide, vincristine, and prednisone in the blood. (Cyclophosphamide, vincristine, and prednisone are part of the CHOP and R-CHOP regimens.) The use of aprepitant is authorized for this experimental purpose. Up to 18 patients will take part in this study. All will be enrolled at M. D. Anderson.