Potential Rett Drug Binding to Its Target (IMAGE) Cold Spring Harbor Laboratory Caption X-ray crystallography shows at the atomic level how Tonks' experimental drug for Rett syndrome, called CPT157633, binds to its target, the enzyme PTP1B, which helps regulate a key metabolic signaling cascade. Credit Tonks Lab, CSHL Usage Restrictions please give credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.