Drug combination unexpectedly flops
By Ben Harder
From Chicago, at the Interscience Conference on Antimicrobial Agents and Chemotherapy
A combination of therapies that researchers anticipated would work well against HIV failed to stop the virus from replicating in more than half the volunteers who received it. A second combination still appears promising, although the study is incomplete.
To compare two experimental drug regimens, researchers gave three antiretroviral drugs to each of 345 volunteers who were infected with HIV. Each day, half the volunteers received one pill containing efavirenz and another containing abacavir and lamivudine. The combination of those drugs is safe and effective against HIV. The other volunteers got tenofovir instead of the efavirenz, as well as the abacavir-lamivudine pill. The researchers then monitored the concentrations of HIV particles in volunteers’ blood.