Peptide Found in Human Blood Inhibits 60 Strains of HIV, Study Says
A peptide found in human blood inhibited 60 strains of HIV from infecting cells in laboratory tests, according to a study published Thursday in the journal Cell, the San Francisco Chronicle reports. Researchers found the peptide can inhibit HIV strains that have developed resistance to existing medications --a discovery that could lead to the development of new HIV/AIDS drugs -- the Chronicle reports. Frank Kirchhoff of the University of Ulm in Germany and colleagues found the peptide, which they call VIRIP, in the residue left in filters used by kidney dialysis patients to clean their blood. According to Kirchhoff, by altering two amino acids, VIRIP's antiviral potency increased one hundredfold. VIRIP attacks a protein, called GP-41 and found on the surface of HIV, that the virus uses to penetrate the surface of human cells, the Chronicle reports. According to Warner Greene, director of the Gladstone Institute of Virology and Immunology who was not involved with the study, VIRIP stands out because it is collected from human blood. He added that the peptide might work synergistically with the antiretroviral drug Fuzeon, which also is known as enfuvirtide or T-20 and was approved by FDA in March 2003. Greene said that it is possible that VIRIP also has potential as an active ingredient for microbicides, which include gels, foams and creams that could be applied prior to sexual intercourse to prevent the sexual transmission of HIV and other sexually transmitted infections. VIRIP can be manufactured in lab settings and has been licensed by the German biotechnology company Viro Pharmaceuticals, whose scientific director is a co-author of the study. According to the Chronicle, Viro is conducting animal studies to determine if VIRIP is safe to test among humans. Although the results so far "look promising," it will take at least five years of animal and human trials before a drug implementing VIRIP is available, according to Kirchhoff.
According to the Chronicle, VIRIP likely will be more costly to produce and will have to be injected because it is a peptide -- a larger and more complex chemical structure than medications made up of chemical compounds. Although the "big advantage of [VIRIP] is that it is available in huge quantities," a "peptide is obviously not ideal" for treating HIV, Kirchhoff said. He added that he hopes additional research will determine how smaller chemical compounds can be created that would perform just as well and in the same way as VIRIP. "In the long-run, we must go away from peptides," he said (Russell, San Francisco Chronicle, 4/20). Roger Pebody, a treatment adviser at the Terrence Higgins Trust, said, "This is early stage research but may be very useful in developing a new class of HIV drugs." He added, "It may take years, but let's hope that this leads to an effective future treatment for HIV" (BBC News, 4/20).
The study is available online.