This study will test an experimental drug called KQB198 in combination with imatinib. The goal is to determine if this combination is safe and tolerable and assess how effective the combination is at treating GIST. Imatinib has been approved by the FDA for the treatment of different types of cancer including GIST.

This phase II trial tests the addition of chemotherapy, with carboplatin and paclitaxel, or chemo-immunotherapy, with carboplatin, paclitaxel and cemiplimab to standard salvage surgery followed by post operative radiation therapy and cisplatin for high risk patients, for the treatment of patients with PD-L1 positive head and neck squamous cell carcinoma that has come back and spread to nearby tissue or lymph nodes after a period of improvement (locally recurrent) or is persistent. Carboplatin is in a class of medications known as platinum-containing compounds. It works in a way similar to the anticancer drug cisplatin, but may be better tolerated than cisplatin. Carboplatin works by killing, stopping or slowing the growth of cancer cells. Paclitaxel is in a class of medications called antimicrotubule agents. It stops cancer cells from growing and dividing and may kill them. Immunotherapy with monoclonal antibodies, such as cemiplimab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Salvage surgery is surgery that takes place to remove tumor tissue after a failure of other treatment. High risk patients also receive radiation therapy uses high energy x-rays, particles, or radioactive seeds to kill cancer cells and shrink tumors. Cisplatin is in a class of medications known as platinum-containing compounds. It works by killing, stopping or slowing the growth of cancer cells. Adding chemotherapy or chemo-immunotherapy to standard salvage surgery may kill more tumor cells than salvage surgery alone in patients with PD-L1 positive locally recurrent or persistent head and neck squamous cell carcinoma.

This phase III trial compares the effect of bevacizumab in combination with carboplatin, paclitaxel and pembrolizumab to the usual treatments of carboplatin and paclitaxel with or without pembrolizumab in treating patients with stage III, IVA or IVB mismatch repair protein proficient (pMMR) and TP53 mutated endometrial cancer that may have spread from where it first started to nearby tissue, lymph nodes, or distant parts of the body (advanced) or that has come back after a period of improvement (recurrent). Bevacizumab is in a class of medications called antiangiogenic agents. It works by stopping the formation of blood vessels that bring oxygen and nutrients to tumor. This may slow the growth and spread of tumor. Carboplatin is in a class of medications known as platinum-containing compounds. Carboplatin works by killing, stopping or slowing the growth of tumor cells. Paclitaxel is in a class of medications called antimicrotubule agents. It stops tumor cells from growing and dividing and may kill them. Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the tumor, and may interfere with the ability of tumor cells to grow and spread. Adding bevacizumab to the combination of carboplatin, paclitaxel and pembrolizumab may be more effective than the usual treatment combinations of carboplatin and paclitaxel with or without pembrolizumab in treating patients with advanced or recurrent pMMR and TP53 mutated endometrial cancer.