Unresectable Dedifferentiated Liposarcoma

This phase III trial compares the effect of immunotherapy (pembrolizumab) plus chemotherapy (doxorubicin) to chemotherapy (doxorubicin) alone in treating patients with dedifferentiated liposarcoma (DDLPS), undifferentiated pleomorphic sarcoma (UPS) or a related poorly differentiated sarcoma that has spread from where it first started (primary site) to other places in the body (metastatic) or that cannot be removed by surgery (unresectable). Doxorubicin is in a class of medications called anthracyclines. Doxorubicin damages the cell's deoxyribonucleic acid (DNA) and may kill tumor cells. It also blocks a certain enzyme needed for cell division and DNA repair. A monoclonal antibody is a type of protein that can bind to certain targets in the body, such as molecules that cause the body to make an immune response (antigens). Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Adding immunotherapy (pembrolizumab) to the standard chemotherapy (doxorubicin) may help patients with metastatic or unresectable DDLPS, UPS or a related poorly differentiated sarcoma live longer without having disease progression.

This phase I trial tests the safety, side effects, and best dose of combination therapy with liposomal doxorubicin and peposertib in treating patients with sarcoma that has spread from where it first started, to other places in the body (metastatic), or cannot be removed by surgery (unresectable) and for which no known cure is available (advanced). Doxorubicin is in a class of medications called anthracyclines. Doxorubicin damages the cell's deoxyribonucleic acid (DNA) and may kill cancer cells. It also blocks a certain enzyme needed for cell division and DNA repair. Liposomal doxorubicin is a form of the anticancer drug doxorubicin that is contained inside very tiny, fat-like particles. Liposomal doxorubicin may have fewer side effects and work better than other forms of the drug. Peposertib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. It may also enhance the activity of chemo- and radiotherapy. There is some pre-clinical evidence in animal models that combining peposertib with liposomal doxorubicin can shrink or stabilize certain types of cancer for longer than either drug alone, but it is not known if this will happen in people. Combination therapy with liposomal doxorubicin and peposertib may be effective in treating patients with advanced sarcoma.

The purpose of this study is to find out whether mirdametinib in combination with palbociclib is an effective and safe treatment for people with metastatic, recurrent, and unresectable liposarcoma. This study will test different doses of mirdametinib in combination with a fixed dose of palbociclib to find the best safe dose for further testing.