A chemotherapy drug with few side effects has been developed by the University of Maryland's Greenebaum Cancer Center, in Baltimore, USA. The drug prevents further division of mutated cancerous cells. When the drug was tested for safety on 34 adult patients of leukemia, it was found that the drug did not have many side effects at lower concentrations. A high dose of 1,200 milligrammes, administered twice a day, could bring about neurological problems such as confusion, lack of balance and visual problems, but these effects disappeared 72 hours after the treatment was stopped. The degree of response shown by the patient varied according to the type of leukemia ( Blood 2001 , Vol 97, p 3361-3369).