Executive Summary

DP-AZT IS MORE POTENT AGAINST HIV-INFECTED CELLS, LESS TOXIC to non-infected cells in tissue culture assays, researchers at the Tulane University School of Medicine in New Orleans report. The modified version of AZT offers promise because of its higher selectivity for HIV cells and lower selectivity for bone marrow cells. Animal studies are currently underway, according to Tulane researcher Sudhir Gogu, PhD. Results of the Tulane study were presented at the 73rd annual meeting of the Federation of American Societies for Experimental Biology (FASEB) in New Orleans. Funded by the National Institutes of Health, the research showed that when tested in cell cultures, DP-AZT "was half as toxic as AZT to mouse bone marrow cells" while it "also inhibited the growth of HIV and the production of viral protein in blood lymphocytes," a FASEB study abstract states. According to the antiviral assay, DP-AZT was 2.5 times more potent than AZT. DP-AZT (dihydro-methyl-pyridinyl-carbonyl-oxy-azidodideoxythymidine) was designed "to achieve sustained levels in the brain," the abstract states. "The new drug remains in the inactive form in certain cells and is more rapidly changed to the active form -- AZT -- in other cells. Once inside cells, DP-AZT is changed by enzymes into AZT." Fortunately, the abstract says, "bone marrow cells do not change DP-AZT to the active form as efficiently as other cells, thereby reducing its toxicity to bone marrow." Krishna Agrawal, PhD, Tulane University, noted that "such an approach may also lead to improved chemotherapy for cancer," since "drugs that are selectively broken down inside tumor cells will be more potent and less toxic."