HMR 1556 is primarily studied for its potential application in the treatment of cardiovascular diseases. It acts as a selective inhibitor of the IKs potassium channel, which plays a significant role in cardiac repolarization. By modulating this channel, HMR 1556 can help regulate heart rhythm and is being explored as a therapeutic agent for conditions like arrhythmias. Its ability to prolong the action potential duration in cardiac cells makes it a candidate for managing certain types of heart rhythm disorders. Research is ongoing to evaluate its efficacy and safety in clinical settings.