Since recently, we have known that dual therapy (two active ingredients instead of three) can keep the viral load undetectable (read more here). But can monotherapy do the same? Researchers see dolutegravir as the best suited drug for monotherapy. It has a high genetic barrier (this means that the virus cannot easily become resistant to it), relatively few side effects and few interactions with other medicines.
At AIDS2018, two studies were presented which looked at whether monotherapy with dolutegravir can keep the viral load undetectable.
The MONCAY Study
The MONCAY study looks at what happens to viral loads if people switch from a treatment regimen of dolutegravir, abacavir and lamivudine to dolutegravir alone. The study involved 158 participants, of which one half switched and the other did not. After 24 weeks, researchers found that, for most people, monotherapy is just as good at suppressing the virus as triple therapy. Nevertheless, the study had to be ended prematurely because more people in the monotherapy group experienced virologic failures than in the triple therapy group. The study concluded that monotherapy with dolutegravir is not safe.
This study looked at whether dolutegravir is effective as a monotherapy in people who started taking HIV inhibitors without six months of becoming infected. It is thought that people who started taking HIV inhibitors early have a smaller HIV reservoir, that less immune activation occurs, and the virus is less diverse. According to researchers, that makes them the ideal group for studying whether monotherapy is effective and safe.
101 participants with an undetectable viral load were divided into two groups: 68 switched to monotherapy and 33 continued with their current therapy. The study found that monotherapy is just as effective as triple therapy for participants who started taking HIV inhibitors within six months of becoming infected and who had a suppressed viral load for at least 48 weeks. The message from researchers is that monotherapy is possible for some people living with HIV.
• Braun DL et al. Simplification to dolutegravir monotherapy is non-inferior compared to continuation of combination antiretroviral therapy in patients who initiated combination antiretroviral therapy during primary HIV infection: A randomized, controlled, non-inferiority trial. 22nd International AIDS Conference, Amsterdam, abstract TUAB0102, 2018.
• Hocqueloux L et al. Dolutegravir monotherapy versus dolutegravir/abacavir/lamivudine for HIV-1-infected virologically suppressed patients: Results from the randomized non-inferiority MONCAY trial. 22nd International AIDS Conference, Amsterdam, abstract TUAB0103, 2018.