This clinical trial is focused on studying a blood cancer called Chronic Myelomonocytic Leukemia (CMML), specifically in patients who are at a higher risk. The study is investigating the safety and effectiveness of a combination treatment using two medications: Venetoclax and Vidaza (Azacitidine). Venetoclax is taken as a tablet, while Vidaza is given as an injection. The purpose of the study is to determine how safe this combination is for patients and how well it works in treating the disease.

Participants in the study will receive the combination of Venetoclax and Vidaza over a period of time. The study is divided into different phases, starting with a safety run-in phase to monitor any side effects. Following this, the main phase of the study will assess how the treatment affects the disease, including the overall response rate, which measures how the disease responds to the treatment. The study will also look at other outcomes, such as how long the response lasts and the overall survival of the participants.

The trial aims to provide valuable information about the potential benefits and risks of using Venetoclax and Vidaza together for treating higher-risk CMML. This information could help improve treatment options for patients with this type of leukemia. Participants will be closely monitored throughout the study to ensure their safety and to gather data on the effectiveness of the treatment.