Elvitegravir with tipranavir/ritonavir or darunavir/ritonavir
Two studies are described evaluating potential pharmacokinetic interactions among elvitegravir and ritonavir-boosted tipranavir or darunavir.
In the tipranavir study healthy volunteers received elvitegravir/ritonavir (200/100 mg once daily) alone, or tipranavir/ritonavir (500/200 mg twice daily) alone, or elvitegravir (200 mg once daily) in combination with tipranavir/ritonavir (500/200 mg twice daily). For the darunavir study subjects received elvitegravir/ritonavir (125/100 mg once daily) alone, or darunavir /ritonavir (600/100 mg twice daily) alone, or elvitegravir (125 mg once daily) in combination with darunavir /ritonavir (600/100 mg twice daily). Steady state pharmacokinetics for elvitegravir, tipranavir, darunavir and ritonavir were determined.
No subjects discontinued for adverse events during treatment with elvitegravir/ritonavir alone. On coadministration, AUC and Cmax of elvitegravir/tipranavir and elvitegravir/darunavir were within respecified no-effect boundaries versus treatment alone; trough concentrations were also not substantially altered. The authors concluded that elvitegravir can be added to tipranavir/ritonavir or darunavir/ritonavir regimens without dose adjustment.
Mathias AA et al. Effect of ritonavir-boosted tipranavir or darunavir on the steady-state pharmacokinetics of elvitegravir. J Acquir Immune Defic Syndr, 2008, 49(2): 156-162.