This study focuses on people with Heart Failure, a condition where the heart cannot pump blood effectively throughout the body. The study will test a new medication called PF-07328948, which is taken as tablets by mouth. Some participants will receive the actual medication while others will receive a placebo. The purpose is to evaluate how well this new drug works and how safe it is for adults with heart failure when taken daily for 36 weeks.

The study will look at patients who have a specific type of heart failure where the heart’s ability to pump blood is only mildly reduced or preserved. Participants must have certain signs of heart failure, including elevated pressure in the heart chambers or previous hospital visits for heart failure symptoms. The study will measure how the treatment affects important aspects of the condition, such as physical function and quality of life.

Throughout the study, researchers will track any heart-related events, measure how far participants can walk in 6 minutes, and assess how participants feel in their daily activities. They will also monitor the levels of substances in the blood that indicate heart stress and keep track of any side effects that may occur during treatment. All participants must also be taking another type of medication called an SGLT2 inhibitor before and during the study.