Clinical trials

The goal of this clinical trial is to learn if the drug istaroxime works to treat cardiogenic shock due to acute heart failure in adults. It will also learn about the safety of istaroxime. Researchers will compare istaroxime to a placebo (a look-alike substance that contains no drug) to see if istaroxime works to treat cardiogenic shock due to acute heart failure. The main questions it aims to answer are: * Does istaroxime relieve participants' shortness of breath compared to a placebo? * Does istaroxime provide clinical benefit in terms of lowering the risk of dying, having invasive procedures, being rehospitalized or having worsening heart failure, and/or increasing quality of life compared to a placebo? * Does istaroxime reduce the duration of the initial hospital stay compared with placebo? Participants will: * Receive a 48-hour intravenous infusion of istaroxime or placebo with possible additional retreatment depending on their clinical condition * Complete questionnaires rating their breathing and describing their quality of life * Return for visits 30 and 90 days after the start of Cycle 1 infusion. The trial will end when the last participant completes Day 30 and all participants have been followed for at least 30 days after their last IMP exposure. At trial termination, participants who have not been followed to Day 90 will have an end-of-study (EOS) visit.