Myelodysplastic/Myeloproliferative Neoplasm With Ring Sideroblasts and Thrombocytosis, Not Otherwise Specified

This phase II trial tests the safety, best dose, and effectiveness of ropeginterferon alfa-2b for the treatment of patients with myelodysplastic syndrome/myeloproliferative neoplasm overlap syndromes and chronic myelomonocytic leukemia. Ropeginterferon alfa-2b is a form of interferon. Interferons are a type of signaling protein normally produced by the body as part of the immune response. Interferons interfere with the division of cancer cells and can slow cancer cell growth. Ropeginterferon alfa-2b is a long-acting form of a type of interferon called interferon alfa-2b. In the body, ropeginterferon alfa-2b causes the production of proteins that modulate the immune system and have anticancer effects.