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Scientists say they have high hopes for a drug that could one
day provide a new form of treatment for HIV-AIDS. A compound, which interferes
with an elusive protein used by the HIV virus to infect human cells, has worked
extremely well in monkeys. If the drug proves effective in human trials,
scientists say, it could bolster (加强) the effectiveness of two existing AIDS
drugs, particularly in fighting drug-resistant strains of the virus.
Researchers at the pharmaceutical (制药的) company Merck are very excited
about an experimental drug, which has worked as well in monkeys infected with a
primate version of the virus as any of the existing, anti-AIDS drugs.
It works by blocking one of three proteins, or enzymes, the HIV virus uses
to gain entrance into and infect human immune system cells.
Inhibitor drugs have been developed to block two of the proteins, to slow
progression of the disease after infection. They have become standard ther