SHP099 is a drug that acts as an inhibitor of the protein tyrosine phosphatase enzyme SHP-2 (PTPN11). It was developed as a potential agent for the treatment of cancer, but while it is potent, orally active and effective at inhibiting SHP-2 activity and slowing tumor growth, it was not developed for clinical use because of dose-limiting side effects. However it continues to be widely used in cancer research and a number of related derivatives have been developed. It has also been used to research the role of SHP-2 in other processes such as regulation of bone growth during development.