PA-457, an
experimental anti-HIV drug in development by Panacos
Pharmaceuticals, shows such promise in suppressing HIV, even
drug-resistant strains of the virus, that developers have
moved it into larger human studies, BBC News reports.
Studies have shown PA-457 reduces HIV viral levels in
treatment-experienced patients by as much as 90%.
The drug is in a
new class of anti-HIV medications called maturation
inhibitors, which interfere with some of the last steps of
the HIV replication cycle. PA-457 works specifically
to block the formation of a protein that coats newly
made copies of HIV. Without the protective coat, viral
copies are unable to infect other cells in the body.
The larger
clinical trials, scheduled to begin this month, will examine
how PA-457 works in conjunction with other anti-HIV drugs in
48 HIV patients with drug-resistant infections.
Panacos officials
say the earliest the drug could be on the market is
2009. (The Advocate)