CROI 2016 Abstract eBook

Abstract Listing

Oral Abstracts

48LB Recovery of Bone Mineral Density After Stopping Oral HIV Preexposure Prophylaxis Robert Grant 1 ; Kathleen Mulligan 1 ;Vanessa McMahan 2 ; AlbertY. Liu 3 ; Juan Guanira 4 ; Suwat Chariyalertsak 5 ; Linda-Gail Bekker 6 ; Mauro Schechter 7 ;Valdilea G.Veloso 8 ; DavidV. Glidden 1 ; for the iPrEx StudyTeam. 1 Univ of California San Francisco, San Francisco, CA, USA; 2 Gladstone Insts, San Francisco, CA, USA; 3 San Francisco Dept of PH, San Francisco, CA, USA; 4 Investigaciones Médicas en Salud, Lima, Peru; 5 Univ of Chiang Mai, Chiang Mai, Thailand; 6 Desmond Tutu HIV Cntr, Cape Town, South Africa; 7 Projeto Praça Onze, Universidade Fed do Rio de Janeiro, Rio de Janeiro, Brazil; 8 Fiocruz, Rio de Janeiro, Brazil Background: Oral pre-exposure prophylaxis (PrEP) containing emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) is associated with small decreases in bone mineral density (BMD) compared with placebo. Whether BMD recovers completely after stopping PrEP is not known.

Methods: The iPrEx trial was a blinded randomized trial of daily oral FTC/TDF PrEP versus placebo among men and transgender women who have sex with men. The randomized phase was followed by an open label extension (iPrEx OLE) that started after a variable gap in PrEP use. An optional substudy measured BMD by dual-energy X-ray absorptiometry (DXA) every 24 weeks during PrEP use, 24 weeks after stopping PrEP, and at the beginning of iPrEx OLE. A concentration of tenofovir-diphosphate (TFV-DP) of 16 fmol per million (fmol/m) viably cryopreserved peripheral blood mononuclear cells was associated with a 90% reduction in HIV incidence and indicated use of 2 to 3 tablets per week. BMD in participants with week 24 TFV-DP levels above 16 fmol/mwere compared with those randomized to receive FTC/TDF who had lower drug concentrations and to those in the placebo group. Results: 498 people were enrolled in the iPrEx DXA substudy, in which BMD decreased during the first 24 weeks of PrEP use (Figure). 352 (71%) had DXA scans 24 weeks after stopping study medication, and 289 (58%) had scans at the start of iPrEx OLE, which occurred a median of 73 weeks (interquartile range: 59 to 87) after stopping study medication. Among those with scans at the start of iPrEx OLE, the median age was 29, and 12% percent identified as trans. Average BMD in the spine and hip accumulated after PrEP use stopped: among those with TFV-DP >16 fmol/m at week 24, average annualized recovery rates after stopping PrEP were 1.81±0.36% in the spine (P=0.01 vs. placebo) and 1.13±0.27% in the hip (P=0.002 vs. placebo). In this group, average BMD recovered completely within 6 months after stopping PrEP in the spine, and by the start of iPrEx OLE in both the hip and spine (Figure). Evidence of BMD recovery persisted after adjusting for differences in study retention by age and drug concentrations and in multiple imputations of BMD values. Conclusions: BMD loss is observed with levels of FTC/TDF PrEP use that are near the minimum required for providing high-level protection from rectal HIV exposure. In this predominately young adult population, there was recovery of BMD to placebo levels after stopping FTC/TDF PrEP.

Oral Abstracts

49 Male Partner Home HIV Testing vs Clinic Invitation in Pregnancy: A Randomized Trial Daisy Krakowiak 1 ; John Kinuthia 2 ; Alfred Osoti 2 ;Victor Asila 3 ; Molly Ann Gone 3 ; Jennifer Mark 1 ; Monisha Sharma 1 ; RuanneV. Barnabas 1 ; Carey Farquhar 1 1 Univ of Washington, Seattle, WA, USA; 2 Kenyatta Natl Hosp, Nairobi, Kenya; 3 Univ of Nairobi, Nairobi, Kenya

Background: Partner HIV testing during pregnancy has been difficult to achieve in sub-Saharan Africa as men seldom attend antenatal appointments. Home-based testing may be an effective alternative method to test partners and identify discordant couples in pregnancy. A randomized clinical trial was conducted in Kenya to determine whether home- based partner education and HIV testing (HOPE) during pregnancy results in higher uptake of testing by partners and increased detection of HIV-discordant couples compared to those who receive a clinic invitation letter. Methods: Pregnant women attending a first antenatal visit at Kisumu East District Hospital from October 2012 to May 2013 were randomized to receive the HOPE intervention or a clinic invitation letter for the woman’s partner (INVITE). The HOPE intervention was a scheduled home visit by a male/female pair of community health workers within 2 weeks of enrollment with couple HIV testing and counseling. In both arms, women had follow-up visits at 6 and 14 weeks postpartum at the clinic and couples had 6 month postpartum home visits. Relative risks were calculated between the two arms. Results: Among 1,101 women screened, 620 (56%) were eligible, and 601 (97%) were enrolled. At enrollment, mean age of women was 24.9 years and 19.1%were HIV positive. Retention was high at 6 months postpartum (88% of women, 86% of men). During the study period, 233 (87%) of 247 men in HOPE reported being tested for HIV during the study period compared to 108 (39%) of 240 men in INVITE (Relative Risk [RR] 2.10; 95% CI: 1.82-2.42). Furthermore, 217 (88%) of 248 women in HOPE knew their partner’s status compared to 98 (39%) of 254 women in INVITE (RR 2.27; 95% CI: 1.93-2.67), 192 (77%) of 248 women in HOPE had been tested as a couple compared to 62 (24%) of 254 women in INVITE (RR 3.17; 95% CI 2.53-3.98) and 33 (13%) of 248 women in HOPE were identified as being in a discordant partnership compared to 10 (4%) of 254 women in INVITE (RR 3.38; 95% CI: 1.70-6.71). Conclusions: Home partner testing resulted in significantly more partner and couple HIV testing, disclosure, and identification of discordant couples compared to a clinic invitation letter to the male partner. This intervention has the potential for prevention of incident HIV infection in pregnancy and MTCT as well as testing harder to reach populations. There is a need to develop strategies to adapt and scale-up similar interventions in settings with high HIV prevalence and lowmale partner participation in PMTCT.

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CROI 2016