CROI 2015 Program and Abstracts

Abstract Listing

Poster Abstracts

Conclusions: All three formulations were found to be safe and acceptable. There was a trend towards higher tissue levels of TFV associated with exposure to the RF gel. Exposure to all three gels was associated with significant inhibition of explant infection. There was a significant negative correlation between compartmental PK and explant infection. Based on these data, either the RGVF or the RF gel could be advanced into later stage development as a candidate rectal microbicide. 995 Female Condom Functionality in the Presence of a Vaginal Ring Annalene M. Nel 1 ; Mildie Leuvennink 1 ; NelietteVan Niekerk 1 ;TerriWalsh 2 ; Ron Frezieres 2 1 International Partnership for Microbicides, Paarl, South Africa; 2 California Family Health Council Inc, Los Angeles, CA, US Background: IPM is evaluating the safety and efficacy of a dapivirine vaginal ring for the prevention of HIV-1 acquisition through male to female transmission. Once the safety and efficacy of the dapivirine vaginal ring have been proven, it should be fully compatible with concurrent use of male and female condoms. The functionality of female condoms (FCs) with the vaginal ring was evaluated. Methods: The total clinical failure rate of FCs in the presence and absence of a placebo vaginal ring was assessed in an open-label, randomized, two-period, crossover non- inferiority trial. Eighty-one healthy, monogamous, heterosexual couples, aged 18-55 years, were enrolled. Each couple used 4 study FCs when the female was wearing the vaginal ring and 4 study FCs when the female was not wearing the ring. The total clinical failure rate was defined as the number of FCs with breakage, complete slippage, misdirection or invagination during intercourse, divided by the number of FCs used. The safety, tolerability and acceptability of FCs in the presence of the vaginal ring and the frequency of ring expulsion or removal were assessed. Results: 297 FCs were used with the vaginal ring and 299 FCs without the ring. The total clinical failure rate was 14.1%with the vaginal ring and 15.7%without the ring. The difference “with ring–without ring” was -2.1% (95% CI: -7.8%; 3.6%). The upper bound of the CI was less than the pre-defined non-inferiority margin of 8%. No clinical breakage during intercourse was reported with or without the ring. Five adverse events (AEs) were reported: genital burning sensation (1 male), pelvic discomfort, bacterial vaginitis and two events of vulvovaginal discomfort (4 females). Two product-related AEs were reported (Grade 1): bacterial vaginitis (with ring) and vulvovaginal discomfort (without ring). No serious AEs were reported; no AE led to trial discontinuation. Use of the vaginal ring resulted in more couples feeling the vaginal ring or FC inner ring, more movement of these rings during intercourse and more interference of the rings with intercourse, which increased the odds of them being bothered by the vaginal ring, affecting sexual satisfaction. Conclusions: Female condom use was safe with vaginal ring use. The presence of the vaginal ring did not negatively affect the total clinical failure rate of FCs. No ring expulsions or removals during intercourse were reported. 2:30 pm– 4:00 pm HIV Testing and the Continuum of Care in the IndustrializedWorld 996 Continuous Retention Predicts Viral Suppression Across the US and Canada Peter F. Rebeiro 1 ; Baligh R.Yehia 2 ; Kelly Gebo 3 ; Bryan Lau 3 ; Kenneth H. Mayer 4 ; Michael A. Horberg 5 ; Mari Kitahata 6 ; John Gill 7 ;Timothy Sterling 1 ; Stephen J. Gange 3 North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) 1 Vanderbilt University, Nashville, TN, US; 2 University of Pennsylvania, Philadelphia, PA, US; 3 Johns Hopkins University, Baltimore, MD, US; 4 Harvard University, Boston, MA, US; 5 Mid-Atlantic Permanente Research Institute, Kaiser Permanente Mid-Atlantic States, Rockville, MD, US; 6 University of Washington, Seattle, WA, US; 7 University of Calgary, Alberta Health Services, Calgary, Canada Background: Retention in care is an HIV care continuum priority. We examined the association between continuous clinical retention (CR) and HIV viral suppression (VS) and evaluated whether this association was similar across geographic regions in the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD), a large, geographically diverse HIV cohort collaboration in the US and Canada. Methods: Adults with ≥ 2 HIV primary care visits ≥ 5 years apart from2000-2012 in NA-ACCORD clinical cohorts were classified as CR if they had ≥ 2 visits within each calendar year, >90 days apart (the US National HIV/AIDS Strategy indicator). Patients’ CR status was assigned for their first 5 years in the cohort. Individuals were assigned to US Centers for Disease Control and Prevention-defined regions or to Canada based on state/province-level residential (12 cohorts) and clinic (2 cohorts) location. VS was defined as an HIV-1 RNA<200 copies/mL at last measurement in the last semester. The prevalence of VS was estimated and the association with CR quantified with prevalence ratios (PR)s usingmodified Poisson regression both overall and by region. Age, sex, race/ethnicity, HIV acquisition risk, baseline CD4+ count, and baseline ART were adjusted for as potential confounders of the CR-VS relationship. Results: Among 37,937 adults contributing 189,685 person-years of follow-up, 38% experienced CR (41% in the Northeast, 43% in the Midwest, 36% in the South, 35% in the West, and 38% in Canada), and CR was significantly associated with increased prevalence of VS (PR=1.41 vs. no CR, p<0.05). The prevalence of VS among those with CR was highest in the West and Canada (68% and 85%, respectively) and lowest in the South (46%), though the influence of CR on VS was of similar strength within every region (p>0.05, Figure). TUESDAY, FEBRUARY 24, 2015 Session P-W1 Poster Session Poster Hall

Poster Abstracts

587

CROI 2015