Anemia caused by chronic kidney disease (CKD) affects approximately 1.2 million cats and dogs in the United States each year. Current treatment options involve the use of medicines designed for humans. These medications are not FDA approved for use in cats and dogs, but in the absence of other treatment options, they are used off-label. Use of human anemia drugs in animals runs the risk of triggering a severe autoimmune reaction that puts the animal's health at great risk. Our intent is to develop a safe medication to treat anemia in companion animals. This medication will be a novel, synthetic peptide that treats anemia, while not triggering the often fatal autoimmune reaction that is caused by repeated use of human anemia drugs. The estimated pet population in the U.S. is 86M owned cats and 78M dogs, according to the American Pet Products Association. The Banfield 2012 State of Pet Health study indicates that 1.5% of cats have CKD. Approximately 30%-65% of cats will develop anemia as their renal disease worsens. CKD is more common in cats, but cancer, another major cause of anemia, is common in dogs. We estimate that approximately 400,000 cats and dogs would receive treatment with this drug each year. In addition to commercialization potential, the proposed study can provide information on synthetic anemia drugs, which can impact human health. The global One Health initiative, a consortium of medical societies, government agencies, and doctors recognizes that human health (including mental health through human- animal bond), animal health, and the ecosystem are inexorably linked. Insight from this study could lead to a new class of synthetic anemia drugs for humans. Our ongoing experiments have identified peptides that bind to the feline and canine receptors responsible for stimulating production of red blood cells. We propose to make these peptides in a form that should activate these receptors, and then test them in cultured cells we will construct using the feline and canine receptors. This will allow us to pick the best peptides as candidates for our new drug. This work will set the stage for testing of the drug candidates in cats and dogs to demonstrate their ability to treat anemia.