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A Study of Pembrolizumab in Patients with Metastatic or Recurrent Ultra-Rare Sarcomas, URSa-1 Trial

Trial Status: active

This phase II trial tests how well pembrolizumab works in treating patients with an ultra-rare (or rare) type of sarcoma, such as pleomorphic liposarcoma, perivascular epithelioid cell tumor (PEComa), epithelioid sarcoma, CIC-rearranged sarcoma, or sclerosing epithelioid fibrosarcoma that has spread from where it first started (primary site) to other places in the body (metastatic) or that has come back after a period of improvement (recurrent). Ultra-rare sarcomas are a soft tissue cancer that is not common (chance of one in a million or lower) and can grow in the smooth muscles or extremities (usually arms and legs). The smooth muscles are in the hollow organs of the body, including the intestines, stomach, bladder, uterus, and blood vessels. Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of cancer cells to grow and spread.