CROI 2020 Abstract eBook

Abstract eBook

Poster Abstracts

776 RILPIVIRINE IN HIV-1–INFECTED WOMEN INITIATING PREGNANCY: TO SWITCH OR NOT TO SWITCH? Pierre Frange 1 , Roland Tubiana 2 , Jeanne Sibiude 3 , Ana Canestri 4 , Cedric Arvieux 5 , Cecile Brunet-Cartier 6 , Laurent Cotte 7 , Sophie Matheron 8 , Jacques Reynes 9 , Laurent Mandelbrot 3 , Josiane Warszawski 10 , Jérôme Le Chenadec 10 , for the ANRS EPF CO1/CO11 Study Group 1 Necker Hospital, Paris, France, 2 AP–HP, Hôpitaux Universitaires Pitié Salpêtrière, Paris, France, 3 Hôpital Louis-Mourier, Colombes, France, 4 Tenon Hospital, Paris, France, 5 CHU de Rennes, Rennes, France, 6 CHU Hôtel-Dieu, Nantes, France, 7 Hospices Civils de Lyon, Lyon, France, 8 AP–HP, Hôpital Bichat-Claude Bernard, Paris, France, 9 CHU de Montpellier, Montpellier, France, 10 INSERM, Le Kremlin-Bicetre, France Background: Data about safety and efficacy of rilpivirine (RPV) during pregnancy remain scarce. Because RPV plasma concentrations are reduced during 2nd and 3rd trimesters of pregnancy and viral breakthroughs were observed, French guidelines recommend switching to RPV-free cART during pregnancy. This study aimed to describe the characteristics of women initiating pregnancy while on RPV and to compare the outcome of virologically- suppressed subjects continuing RPV until delivery or switching to RPV-free cART. Methods: We included all women in the French Perinatal HIV cohort receiving RPV at the time of conception in 2010-2018, with prospective, monthly follow- up of pregnant women and pediatric follow-up from birth to 18–24 months. We compared maternal and infant characteristics in case of maintain of RPV throughout pregnancy or switch to RPV-free cART. In women with available results of HIV-1 viral load (VL) before 14 weeks of gestation (WG) and viral suppression (VL<50 copies/mL) while on RPV, we compared the probability of viral rebound (≥50 copies/mL) during pregnancy between those continuing RPV versus those switching to RPV-free cART. Results: Overall, 248 women were receiving RPV, mostly combined with TDF/FTC in single-tablet regimens (93.5%). At the beginning of pregnancy, most women were virologically suppressed (88.2%) and median CD4 count was 564/µL (IQR: 431-716). During pregnancy, 185 women (74.6%) switched to RPV-free cART (mostly IP/r + NRTI(s)), at a median gestational age of 8.0 WG (IQR: 6.0 – 12.0). The VL nearest delivery was <50 copies/mL in 95.7% of women. Few adverse events occurred during pregnancy (birth defects: 3.8%; ectopic pregnancies: 0.4%; stillbirths: 1.6%; preterm deliveries: 8.9%; very preterm deliveries; 2.8%) with similar proportions in patients continuing RPV and in those switching to RPV-free cART. The characteristics of newborns were similar between groups. No child was infected with HIV. Among 69 women with documented viral suppression before 14 WG, the risk of viral rebound during pregnancy was significantly higher when switching to a RPV-free cART than when continuing RPV until delivery (21.0% versus 0.0%, p = 0.046) (Figure). Conclusion: Continuing RPV in virologically-suppressed women initiating pregnancy may be associated with better virological outcome than changing cART. Larger studies are required to confirm these results and establish the safety of fetal exposure to RPV in the long term.

777 COST-EFFECTIVENESS OF BROADLY NEUTRALIZING ANTIBODIES FOR INFANT HIV PROPHYLAXIS Caitlin Dugdale 1 , Sallie Permar 2 , Lynda Stranix-Chibanda 3 , Rochelle P. Walensky 1 , Genevieve Fouda 2 , Landon Myer 4 , Coleen K. Cunningham 5 , Milton C. Weinstein 6 , Valériane Leroy 7 , Elizabeth J. McFarland 8 , Kenneth Freedberg 1 , Andrea L. Ciaranello 1 1 Massachusetts General Hospital, Boston, MA, USA, 2 Duke Human Vaccine Institute, Durham, NC, USA, 3 University of Zimbabwe, Harare, Zimbabwe, 4 University of Cape Town, Cape Town, South Africa, 5 Duke University, Durham, NC, USA, 6 Harvard T.H. Chan School of Public Health, Boston, MA, USA, 7 INSERM, Toulouse, France, 8 University of Colorado Anschutz Medical Campus, Aurora, CO, USA Background: Injectable infant prophylaxis with a broadly neutralizing antibody (bNAb) could help overcome gaps in the prevention of vertical HIV transmission cascade by providing long-acting protection from postnatal transmission, but there are few insights into the potential cost-effectiveness of this strategy. Methods: Using the Cost-effectiveness of Preventing AIDS Complications (CEPAC)-Pediatric model, we simulated children known to be HIV-exposed from birth through death in South Africa. We compared four strategies: standard of care oral prophylaxis for 6-12 weeks per WHO guidelines (SOC), and oral prophylaxis plus a bNAb given at birth (bNAb birth), birth and 3 months (bNAb birth+3 m), or every 3 months throughout breastfeeding (bNAb extended). Base-case model inputs, varied in sensitivity analyses, included: prophylaxis uptake (oral: 50-86%, bNAb: 54-96%, each by month postpartum), preventive efficacy (oral: 90%, bNAb: 80%), duration of effect (bNAb: 3m), costs (oral: $7-11/m, bNAb: $60/dose), and mean breastfeeding duration (both: 6m). Simulated transmission risks were based on maternal ART use, viral load, and breastfeeding status. Model outcomes included total pediatric HIV incidence, pediatric life-expectancy (LE), lifetime HIV-related per-person costs (2019 USD), and incremental cost-effectiveness ratios (ICERs) calculated from discounted (3%/y) LE and costs. We defined cost-effective as an ICER <$900/YLS. Results: All bNAb strategies led to lower total pediatric HIV incidence and greater LE, but greater lifetime HIV-related costs than SOC (Fig 1). bNAb extended was the preferred strategy and was cost-effective: ICER $420/YLS vs. SOC. bNAb extended remained the preferred strategy unless bNAb efficacy was <60% or costs exceeded $100/dose. When the analysis was restricted to only high-risk infants, as defined by WHO infant prophylaxis guidelines, bNAb extended remained the preferred strategy and was cost-effective at base case bNAb costs and efficacy. Conclusion: At current estimates of efficacy and costs as high as $100/dose, bNAb prophylaxis for children who are HIV-exposed throughout breastfeeding would be a cost-effective strategy to prevent vertical HIV transmission in South Africa. More data on the efficacy of bNAb prophylaxis for infants and its implementation costs in sub-Saharan Africa are needed.

Poster Abstracts

CROI 2020 287