2.5 Drug parameters
Raltegravir (RAL) was included in this study as a probe substrate for
the activity of UGT1A1 in pregnancy. RAL is solely metabolised by UGT1A1
and can be used to validate the ontogeny pf UGT1A1 in both pregnant and
non-pregnant populations. Similarly, clinical PK data of RAL in both
populations are available. Unlike CAB, clinical PK data for oral RPV in
pregnancy are available [20, 21, 41]. However, there are no
available PK data for LAI RPV in pregnancy. Physicochemical properties
and in vitro data for the drugs modelled in this study (RPV, RAL and
CAB) are listed in Table 1. Renal drug clearance was not implemented in
the model as all three drugs are mainly cleared by the liver.