A randomized trial done in Kenya has found out that switching people living with HIV from a ritonavir-boosted protease inhibitor (PI) to a dolutegravir (Tivicay)-based regimen maintained viral suppression just as well.
According to a study published in the New England Journal of Medicine , done by Loice A. Ombajo, infectious disease specialist and lecturer at the University of Nairobi in Kenya, and colleagues conducted a prospective, open-label trial at four sites in Kenya involving patients without genotype information who had viral suppression while receiving treatment containing a ritonavir-boosted PI.
Participants were randomly assigned to switch to dolutegravir or continue the current regimen (398 and 397, respectively). The primary end point was a plasma HIV type 1 RNA level of at least 50 copies/mL at week 48.
“High pill burdens, long-term toxic effects, challenges regarding side effects, and high costs of regimens containing a ritonavir-boosted PI are well-established and are considerable disadvantages of the current second-line regimens in much of sub-Saharan Africa,” the group explained. “In settings with a high prevalence of tuberculosis, the effect of potential drug–drug interactions between a ritonavir-boosted PI and rifampin is considerable.”
The researchers found that at week 48, 5.0 and 5.1 percent of patients in the dolutegravir and ritonavir-boosted PI groups, respectively, met the primary end point, a result that met the criterion for noninferiority. At the time of treatment failure, the investigators observed no mutations conferring resistance to dolutegravir or the ritonavir-boosted PI. A similar incidence of treatment-related grade 3 or 4 events was seen in the dolutegravir and ritonavir-boosted PI groups (5.7 and 6.9 percent, respectively).
This trial provides information that can inform the current distribution of treatment regimens in Kenya and other similar settings, thus enabling consideration of a transition from ritonavir-boosted PI-based regimens to a dolutegravir-based regimen in almost 75 percent of patients currently receiving second-line therapy, which would provide advantages with regard to cost, risk of toxic effects, risk of drug-drug interactions, and pill burden.
The study was funded by ViiV Healthcare, the manufacturer of dolutegravir.