Rigosertib (ON-01910 sodium salt, with Estybon as trade name) is a synthetic benzyl styryl sulfone in development by Onconova Therapeutics. Rigosertib is in phase III clinical trials for the treatment of chronic myelomonocytic leukemia.
Its geometrical isomer (Z)-ON 01910÷Na has less cytotoxicity on cancer cells.
Rigosertib is a microtubule-destabilizing agent.