Pazopanib, Lapatinib or Trastuzumab in Subjects With Solid Tumors

Study Groups: If you are found to be eligible to take part in this study, your doctor will decide which study drugs you will receive based on the disease type and the drugs you have taken in the past You will receive either a combination of pazopanib and lapatinib (Arm A) or a combination of pazopanib and trastuzumab (Arm B). Up to 5 dose levels of each combination will be tested. Up to 6 participants will be enrolled at each dose level of each combination. The first group of participants will receive the lowest dose level of each combination. Each new group(s) will receive a higher combination than the group before it, if no intolerable side effects were seen. Participants may be enrolled on 1-3 similar dose levels at the same time. You will be assigned to a dose level based on when you joined this study. This will continue until the highest tolerable dose(s) of the study drug combination is found. The dose of the study drug combination that you receive may be lowered if you have intolerable side effects. Once the highest tolerable doses of the different combinations are found, this dose of each combination will be given to an expansion group of 20 extra participants. Study Drug Administration: If you are in Arm A, you will take lapatinib by mouth 1 time each day. You will take pazopanib by mouth 1 time every other day (Day 1, 3, 5, and so on). You should take pazopanib and lapatinib either 1 hour before or 2 hours after eating a meal. If you are in Arm B, you will take pazopanib by mouth 1 time each day. You will receive trastuzumab by vein on Days 1, 8, 15, and 22 of each cycle. The first infusion will be over 90 minutes. If you handle the infusion well, the next infusions will be over 30 minutes. You should take pazopanib either 1 hour before or 2 hours after eating a meal. Each study cycle is 28 days. Study Visits: At all study visits, you will be asked about any drugs you may be taking and side effects you may be having. Week 3 of Cycle 1, blood (about 1 teaspoon) and urine will be collected for routine tests. During Week 3 of Cycles 2 and beyond, blood (about 1 teaspoon) will be drawn for routine tests. During Week 4 of Cycle 2 and then every 2-3 cycles: * You will have a CT scan, MRI scan, PET scan, and/or x-ray to check the status of the disease. * If the study doctor thinks it is needed, blood (about 1 teaspoon) will be drawn to measure tumor markers. Length of Study: You may continue taking the study drugs for as long as the doctor thinks it is in your best interest. You will be taken off study early if the disease gets worse, if you continue to have intolerable side effects, or if you are unable to follow study directions. Your participation on the study will be over once you have completed the end-of-study visit. End-of-Study Visit: Within 30 days after your last dose of study drugs, you will have an end-of-study visit. At this visit, the following tests and procedures performed: * Your medical history will be recorded. * You will have a physical exam. * You will be asked about any drugs you may be taking and side effects you may be having. * Your weight, vital signs, and performance status will be recorded. * Blood (about 2 teaspoons) and urine will be collected for routine tests. * If the study doctor thinks it is needed, blood (about 1 teaspoon) will be drawn to measure tumor markers. * If the study doctor thinks it is needed, you will have a chest x-ray, CT scan, MRI scan, and/or PET scan to check the status of the disease. This is an investigational study. Pazopanib is FDA approved and commercially available for the treatment of renal cell carcinoma. Lapatinib and trastuzumab are FDA approved and commercially available for the treatment of breast cancer. The combination of pazopanib and lapatinib or pazopanib and trastuzumab is investigational. Up to 174 participants will take part in this study. All will be enrolled at MD Anderson.