tokens: The protective effect of oral administration of the thiol compound sodium 2-mercaptoethane sulphonate ( MESNA ) against urothelial toxicity induced by ifosfamide ( IF ) was tested in a group of 45 patients with inoperable lung cancer under treatment with IF ( 2250 mg / m2 on days 2 - 5 ) as part of a polychemotherapy regimen repeated in a 4 - week cycle .