An antibody combined with a powerful chemotherapy drug shows promise in killing or decreasing acute lymphoblastic leukemia (ALL) cells. Antibodies are part of the body's immune system and work to fight off foreign invaders.
The University of Texas MD Anderson Cancer Center study found the combination therapy either eradicated or greatly reduced the disease in 61 percent of the 46 patients in the phase II study.
"New drug therapy helps fight acute lymphblastic leukemia."
The drug called inotuzumab ozogamicin, or CMC-544, links an antibody to a protein that's found on the surface of more than 90 percent of ALL cells. When the chemotherapy agent is added, the ALL cell draws it inside and dies.
Study participants included patients with ALL that resisted other therapies or had returned after treatment. Response rates for these second option therapies usually run between 20-30 percent. The combination therapy saw a 61 percent response rate.
Having a response rate of more than 50 percent in these patients makes CMC-544 the most effective single agent for ALL ever used, according to Hagop Kantarjian, M.D., professor and chair of MD Anderson's Department of Leukemia and study senior investigator.
Researchers say that combining inotuzumab with other chemotherapy medications might improve ALL treatment even more. Different dosing regimens may also improve results.
The study findings were presented at the 2011 American Society of Clinical Oncology annual meeting.
According to National Cancer Institute estimates, some 5,330 people received an ALL diagnosis in 2010 and 1,420 died of the disease. It's the most common form of cancer in children. Combined chemotherapy regimens have increased long-term survival from 5 percent of pediatric patients in the 1960s to 85 percent today.