Study Groups:~If you are found to be eligible to take part in this study, you will be assigned to a dose level of the study drugs based on when you join the study.~Up to 5 dose level combinations of regorafenib and cetuximab will be tested. Up to 3 participants will be enrolled at each dose level. The first group of participants will receive the lowest dose level combination. Each new group will receive a higher dose of either regorafenib or cetuximab than the group before it, if no intolerable side effects were seen. This will continue until the highest tolerable dose combination of regorafenib and cetuximab are found.~Once the highest tolerable dose combination is found, up to 10 more participants may be enrolled. This group (called the Dose Expansion group) is enrolled to help researchers study the safety and effectiveness of this dose level combination.~Study Drug Administration:~Each study cycle is 28 days.~You will take regorafenib by mouth on Days 1-5, 8-12, and 15-19 of each cycle. You will swallow the whole capsules with 1 cup of water (about 8 ounces) 1 time a day. Do not break, chew, or open your capsules. The doctor will discuss this with you.~You will receive cetuximab by vein over about 1-2 hours on Days 1, 8, 15, and 22 of each cycle.~Study Visits:~At each cycle, you will be asked to complete a questionnaire so the study team will better understand any symptoms you may be having that are related to use of the study drug.~On Day 1 of Cycle 1, blood (about 4 teaspoons) and urine will be collected for routine tests and pharmacodynamic (PD) tests. PD testing measures how the level of study drug in your body may affect the disease.~Between Days 8 and 14, Days 15 and 21, and Days 22 and 28 of Cycle 1:~°Blood (about 4 teaspoons) will be drawn for routine tests.~On Day 1 of Cycles 2 and beyond:~You will have a physical exam.~Urine will be collected for routine tests.~Once a week, blood (about 4 teaspoons) will be drawn for routine tests.~Every other cycle (every 8 weeks):~°You will have an x-ray and a CT scan to check the status of the disease.~Length of Study:~You may continue receiving regorafenib and cetuximab for as long as the doctor thinks it is in your best interest. You will no longer be able to take the study drugs if the disease gets worse, if intolerable side effects occur, or if you are unable to follow study directions.~You will be off study after the end-of-study visit.~End of Study Visit:~About 30 days after your last dose of study drugs:~You will have a physical exam.~Blood (about 4 teaspoons) and urine will be collected for routine and PD tests tests.~You will have an x-ray and a CT scan to check the status of the disease.~Follow-up:~You will be asked about any health problems you may have and if you have had any side effects. If your study doctor thinks it is needed, you may have follow-up for a longer period of time.~This is an investigational study. Regorafenib is FDA approved for the treatment of metastatic colorectal cancer. Cetuximab is FDA approved for the treatment of K-Ras wild type colorectal cancer as well as head and neck cancer. The combination of regorafenib and cetuximab is currently being used in advanced solid tumor patients for research purposes only.~Up to 83 patients will be enrolled in this study. All will take part at MD Anderson.
The goal of this clinical research study is to find the highest tolerable dose of the combination of regorafenib and cetuximab that can be given to patients with advanced solid tumors. The safety and effectiveness of this drug combination will also be studied.