An analysis of previously reported data beyond week 48 reinforces the clinical utility of baseline factors in the appropriate use of cabotegravir + rilpivirine long-acting (CAB + RPV LA). “Inclusion of initial model-predicted CAB/RPV trough concentrations (≤1st quartile) did not improve the prediction of [confirmed virologic failure (CVF)] beyond the presence of a combination of ≥2 baseline factors,” the authors conclude.
Using pooled data from 1,651 participants on 4- or 8-week dosing regimens, the authors looked at 2 models: baseline factor analyses exploring factors known at baseline and multivariable analyses exploring baseline factors plus post-baseline model-predicted CAB/RPV trough concentrations (4 and 44 weeks after injection). “Overall, 1.4% (n = 23/1,651) of participants had CVF through 152 weeks. The presence of RPV resistance-associated mutations (RAMs), HIV-1 subtype A6/A1, and body mass index (BMI) ≥ 30 kg/m2 was associated with an increased risk of CVF (P < 0.05 adjusted incidence rate ratio), with participants with ≥2 of these baseline factors having a higher risk of CVF. Lower model-predicted CAB/RPV troughs were additional factors retained for multivariable analyses.”