ACT-281959 (molecular weight 850.9 g/mol), the di-ester prodrug of ACT-246475 (molecular weight 618.6 g/mol), was developed to improve absorption after oral dosing and is rapidly converted by esterases in vivo to ACT-246475 in two-steps via the formation of ACT-409100 (molecular weight 734.7 g/mol), the mono-ester prodrug. ACT-281959 is a novel potent and selective P2Y12 receptor antagonist with a wider therapeutic window. ACT-281959 showed antithrombotic efficacy after oral administration in the rat ferric chloride model. ACT-281959 entered clinical studies in healthy volunteers. ACT-281959 had been in phase I clinical trials by Actelion for the treatment of thrombosis. But there is no development reported for this study recently.

MDCO 700 (formerly ABP 700) is hypnosedative and anaesthetic agent that was being developed by The Medicines Company for the induction of general anesthesia and procedural sedation. It is a positive allosteric modulator of the GABAA receptor. It is a second generation analogue of etomidate, developed to retain etomidate's beneficial haemodynamic and respiratory profile but diminishing its suppression of the adrenocortical axis. Infusions of ABP-700 showed a dose-dependent hypnotic effect, and did not cause severe hypotension, severe respiratory depression, or adrenocortical suppression. The drug development for anaesthesia has been discontinued.