Arginine deprivation therapy, based on a PEGylated genetically modified human arginase technology, targets cancer growth and survival by removing the supply of arginine to a proportion of cancers with disrupted urea cycle. A significant proportion of cancer types lack the ability to synthesize arginine due to deficient expression of certain metabolic enzymes of the urea cycle, including argininosuccinate synthetase 1, argininosuccinate lyase or ornithine transcarbamylase.

The FDA allowed the Company’s Investigational New Drug application for the arginase biologic product, PT01 (also known as Pegtomarginase), for the treatment of patients with advanced malignancies in 2019. PT01 is currently in Phase 1.

We believe this therapeutic has significant potential for patients both as a monotherapy as well as in combination with other Athenex therapeutics.