The study is looking at how safe and effective a new drug, called R2R01, is when used with the usual treatment for heart failure, compared to the usual treatment alone. Heart failure is when the heart can't pump blood as well as it should. The study lasts up to 51 days and involves taking the study drug or a placebo (a fake treatment) once a day for 7 days. There are four groups, each receiving different doses of R2R01 or a placebo. Patients need to be at least 18 years old, have worsening heart failure, and be able to take care of themselves at home. They must stay in the clinic for 3 days during the study for observation. The study will happen at 8 centers across the US, and only outpatients will participate, meaning you won't be admitted to the hospital for the study.

• Study Duration: Up to 51 days with a 3-day clinic stay.
• Treatment: Daily dose of R2R01 or placebo for 7 days.
• Eligibility: Must have heart failure and be 18 or older.