Hydroxymethylbutyrate and eicosapentaenoic acid: Preclinical studies to improve muscle function in critical care medicine

This review will discuss the effects of two biopharmaceuticals, hydroxymethylbutyrate (HMB) and eicosapentaenoic acid (EPA). HMB is a safe agent, with no known side effects. HMB alters skeletal muscle function by increasing muscle protein synthesis and decreasing proteolysis. HMB has been used in cancer patients and the elderly and has been demonstrated to improve muscle mass and function in these populations. However, HMB has not been tested in large clinical trials in critically ill patients. EPA is relatively safe and has been shown to increase muscle protein synthesis and reduce proteolysis. EPA has been tested in animal models of disease and in several patient populations. Most of these studies indicate that EPA can improve muscle mass and function without significant side effects. In one recent study, the OMEGA trial, a mixture of EPA and several other agents increased mortality in critically ill patients. As a result, EPA administration cannot currently be recommended for critically ill patients outside of a clinical trial.