A new mathematical model of HIV-fighting drugs reveals the biology beneath the varying success of such treatments. Infection with HIV was a death sentence until the introduction of multidrug cocktails, yet the differential effectiveness of the combinations has remained a puzzle. The research, published July 13 in Science Translational Medicine, could help refine therapies for HIV and other viruses such as hepatitis C.
Slightly boosting the dose of some HIV drugs has a profound effect if those drugs are attacking multiple targets, the new model reveals. Finding that more bullets can kill more targets may seem obvious, says AIDS researcher and Howard Hughes Medical Institute investigator Robert Siliciano of Johns Hopkins University. But the realization required a shift in thinking about a very old idea: the relationship between a drug’s dose and its effect.
For centuries, drug effectiveness has been visualized with what’s called the dose-response curve. This relationship often takes on a stretched-out “S” shape when graphed.