Distribution: Dolutegravir is highly bound (≥98.9%) to human plasma proteins based on
in vivo data and binding is independent of plasma concentration of dolutegravir. The apparent
volume of distribution (Vd/F) following 50-mg once-daily administration is estimated at 17.4 L
based on a population pharmacokinetic analysis.
Cerebrospinal Fluid (CSF): In 11 treatment-naïve subjects on dolutegravir 50 mg
daily plus abacavir/lamivudine, the median dolutegravir concentration in CSF was 18 ng/mL
(range: 4 ng/mL to 232 ng/mL) 2 to 6 hours postdose after 2 weeks of treatment. The clinical
relevance of this finding has not been established.