aTyr Pharma Inc is a biotherapeutics company, engaged in the discovery and clinical development of medicines for patients suffering from severe, rare diseases using its Physiocrine biology. It has discovered approximately 300 Physiocrines, a class of naturally occurring human proteins that it promotes homeostasis, a fundamental process of restoring stressed or diseased tissue to a healthier state. The company is developing Resolaris, an intravenous protein therapeutic for the treatment of rare myopathies with an immune component. Business activity is primarily conducted through the United States.