Myer L, Redd AD, Mukonda E, Lynch BA, Phillips TK, Eisenberg A, Hsiao NY, Capoferri A, Zerbe A, Clarke W, Lesosky M, Breaud A, McIntyre J, Bruno D, Martens C, Abrams EJ, Reynolds SJ.
Clin Infect Dis. 2019 Mar 16. pii: ciz209. doi: 10.1093/cid/ciz209. [Epub ahead of print]
Elevated viral load (VL) early after antiretroviral therapy (ART) initiation appears frequently in pregnant and postpartum women living with HIV, however the relative contributions of pre-ART drug-resistant mutations (DRM) versus non-adherence in the aetiology of elevated VL are unknown.
Within a cohort of women initiating ART during pregnancy in Cape Town, South Africa, we compared women with elevated VL after initial suppression (cases, n=80) incidence-density matched to women who maintained suppression over time (controls, n=87). Groups were compared on pre-ART DRM and detection of antiretrovirals in stored plasma.
The prevalence of pre-ART DRM was 10% in cases and 5% in controls (adjusted odds ratio [OR], 1.53; 95% confidence intervals [CI]:0.40-5.86); all mutations were to non-nucleoside reverse transcriptase inhibitors. At the time of elevated VL, 19% of cases had antiretrovirals detected in plasma, compared to 87% of controls who were suppressed at a matched time point (aOR, 131.43; 95% CI:32.75-527.40). Based on these findings we estimate that <10% of all elevated VL in the cohort may be attributable to pre-ART DRM versus >90% attributable to ART non-adherence.
DRM account for a small proportion of all elevated VL among women occurring in the 12 months after ART initiation during pregnancy in this setting, with non-adherence appearing to drive most episodes of elevated VL. Alongside the drive for access to more robust antiretroviral agents in resource-limited settings there is an ongoing need for effective strategies to support ART adherence in this patient population.