Background:
HIV-2 infection remains a significant health problem in West Africa. Choices of antiretroviral drugs (ARVs) are limited but HIV-2 is fully susceptible to all nucleoside inhibitors (NRTIs) and integrase inhibitors (INSTIs). Bictegravir is active in vitro but no clinical data are available.
Methods:
A retrospective study of patients (Pts) followed for HIV-2 infection in the Infectious Diseases Unit at Bichat Hospital, Paris, France and treated with BIC/FTC/TAF. Data were obtained from flow charts after patients’ written informed consent and were censored at September 1st 2022.
Results:
Twenty-four Pts living with HIV-2 (PLHIV-2) received BIC/FTC/TAF, 14 women and 10 men. Median age was 56 yrs [IQR 50.2-60.2], median time since HIV-2 infection diagnosis was 19 yrs [IQR 8-23] and median nadir CD4 cell count 319/mm3 [IQR 174-432]. Zenith viral load was below 100 c/mL in 13 Pts and detectable in 11 Pts with a median value of 597 c/mL [IQR 513-567]. Five Pts were treatment-naive and 19 were receiving ARVs with a median of 2 [IQR 1-3] previous regimens. ARVs preceding switch to BIC/FTC/TAF was a backbone of 2 NRTIs combined with darunavir/r in 5 Pts, raltegravir in 10 Pts, and dolutegravir in 4. Eight of these 19 pretreated patients had an history of treatment failure.At time of BIC/FTC/TAF initiation, median CD4 cell count was 580/mm3 [IQR 380-697]. Three Pts only, all naïve, had detectable viral load (57, 94 et 130 c/mL) with a viral load assay threshold of 40 c/mL At time of evaluation, the median duration of BIC/FTC/TAF treatment was 21.7 months IQR [12.9-30.4]. No Pt discontinued treatment. Viral load was < 40 c/mL in all Pts. Median CD4 cell count was 655/mm3 [IQR 495-800], p = 0.06 by Wilcoxon signed rank test when compared with CD4 count at time of BIC/FTC/TAF initiation.
Conclusions:
In this observational study of PLHIV-2, BIC/FTC/TAF was well tolerated and efficient to achieve or maintain suppression of HIV-2 replication in all Pts. These results suggest that this BIC/FTC/TAF single-tablet-regimen is a valuable treatment option in PLHIV-2. Furthermore, TAF has a reduced risk of renal toxicity compared to TDF and is active against B hepatitis virus infection, that is frequent in Africa and overlaps with HIV-2 epidemics. More data in ARV-naive PLHIV-2 with detectable viral load at time of ARVs initiation should now be obtained to confirm the value of this combination in the treatment of HIV-2 infection.