ST789: a new synthetic immunomodulator

ST 789 is a synthetic compound which belongs to a new family of hypoxanthine derivatives exhibiting an aminoacidic function at the N-9 position of the purine ring. Available literature indicates that hypoxanthine derivatives exhibit well established immunomodulant properties. Furthermore, the addition of arginine to these molecules proved able to strongly enhance their immunomodulant activity. We review here the immunomodulant properties of both arginine and arginine-containing compounds, and mostly of ST 789.