SAN DIEGO - Adding a drug that activates genes to frontline combination therapy for acute myeloid leukemia resulted in an 85 percent remission rate after initial treatment, researchers at The University of Texas MD Anderson Cancer Center reported at the 53rd Annual Meeting of the American Society of Hematology.
Results of the Phase II clinical trial of 75 patients set the stage for a national Phase III clinical trial of the new combination compared to standard-of-care frontline combinations used at MD Anderson and elsewhere, said study leader Guillermo Garcia-Manero, M.D., professor in MD Anderson's Department of Leukemia.
Study patients received the drug vorinostat, known commercially as Zolinza, a histone deacetylase inhibitor, in addition to the chemotherapy drug cytarabine and idarubicin, an anthracycline antibiotic commonly used as chemotherapy.
"The overall response rates are encouraging, and most higher risk patients did very well," Garcia-Manero said. He will be the principal investigator of the Phase III trial, which will be conducted through the National Cancer Institute's Cooperative Oncology Groups.
Vorinostat activates suppressed genes by protecting acetyl chemical groups that adhere to histone proteins, which are connected to DNA like beads on a string. Acetylated histones make genes more accessible for transcription, so vorinostat presumably works by reactivating blocked tumor-suppressing genes.
According to the NCI's Surveillance Epidemiology and End Results database, about 14,000 new cases of AML are diagnosed annually in the United States and the disease kills about 9,000 people each year. AML is characterized by swift proliferation of immature white blood cells in the blood and bone marrow that crowds out normal cells, leaving patients exposed to infection, severe anemia and bleeding.
High response for higher risk patients
Overall, 57 patients achieved complete remiss
|Contact: Scott Merville|
University of Texas M. D. Anderson Cancer Center