Foscarnet as salvage therapy in HIV-2-infected patient with antiretroviral treatment failure

Previous studies have suggested the efficacy of foscarnet combined with thymidine analogues as salvage therapy in late-stage HIV-1 infection. Here, we report on the first case of foscarnet therapy in a patient infected with HIV-2 exhibiting virologic failure. The patient was known to be HIV-2-infected since 1992 and had received 11 sequential lines of combined antiretroviral therapy (cART) with almost all the available antiretroviral agents including raltegravir. A marked decrease in HIV-2 plasma viral load of 1.48log10copies/ml was observed at day 14 of foscarnet induction therapy associated with zidovudine and failing cART. An optimized cART was then introduced with lamivudine, zidovudine, lopinavir/r, etravirine and maraviroc. Four months after the end of foscarnet therapy, HIV-2 plasma viral load remained undetectable. This case report suggests that foscarnet may represent a therapeutic option for HIV-2-infected patients exhibiting multidrug resistance.