This study looks at how a medicine called maridebart cafraglutide can help people with heart failure (HF) who are also obese. Heart failure happens when the heart doesn't pump blood well. The study focuses on two types: HF with preserved ejection fraction (HFpEF) and HF with mildly reduced ejection fraction (HFmrEF). Ejection fraction is a measure of how well the heart pumps. The trial is a phase 3 study, meaning it's in the late stages where it's tested on many people to see how well it works and if it's safe. It includes a double-blind period where neither the participants nor the researchers know who gets the actual medicine or a placebo, and an open-label extension (OLE) where everyone knows the treatment being given.

• The study lasts until about 850 heart-related events are recorded.
• Participants must be at least 18 years old and have a BMI of 30 or higher.
• People with certain heart conditions or uncontrolled diabetes cannot join.