High level of retention and adherence at week 48 for MSM and TGW enrolled in the PrEP Brasil demonstration study Beatriz Grinsztejn, Brenda Hoagland, Ronaldo I. Moreira, Esper G. Kallas, Jose V. Madruga, Iuri C. Leite, Raquel de Boni, Peter L. Anderson, Albert Liu, Paula M. Luz, Valdiléa G. Veloso Supported by: Truvada® donated by Gilead Sciences. Inc.

Research recipient from Gilead, BMS, GSK/ViiV, Merck Truvada fro PrEP Brasil was donated by Gilead Drug levels assessments were sponsored by Gilead

OBJECTIVE PrEP Brasil is a demonstration study to assess feasibility of daily oral tenofovir-disoproxil-fumarate plus emtricitabine (TDF/FTC) provided at no cost to PrEP-naïve high-risk men who have sex with men (MSM) and transgender women (TGW) within the Brazilian public health system. We report week 48 PrEP retention, adherence to daily pill use, trends in sexual behavior and incidence of HIV and sexually transmitted infections. METHODS Study period: April 2014 to July 2016 3 centers in Rio de Janeiro and São Paulo Dried blood spots (DBS) were collected for tenofovir-diphosphate (TFV-DP) and FTC-triphosphate (FTC- DP) measurements at the University of Colorado Antiviral Pharmacology Laboratory All participants: DBS at weeks 4 and 48. Young MSM (18-24 years) and TGW: all visits At each visit: HIV and syphilis testing, CASI used to assess sexual risk and substance use At enrollment and week 48: rectal Chlamydia trachomatis and Neisseria gonorrhea A pilot sub-study of interactive text messages (SMS) was offered to all participants, those who agreed to participate were randomized 1:1 to receive messages. PrEP Retention: attendance of the week 48 visit, irrespective of attendance to other study visits. PrEP Engagement: ordinal five-level variable combining presence in the study visit and drug levels: (1) Missing visit, (2) No detectable medication (TFV-DP level undetectable), (3) TFV-DP consistent with less thank 2 doses/week, (4) TFV-DP 2-3 doses/week and (5) TFV-DP ≥4 doses/week. PrEP Adherence: dichotomous variable defined TFV-DP <700 fmol/punch and TFV-DP ≥700 fmol/punch.

RESULTS PrEP retention: 450 participants initiated PrEP, of which 376 (83%) were retained through 48 weeks PrEP engagement: PrEP adherence: 74% (277/450) had protective levels consistent with ≥4 doses/week ≥ 4 doses/ week in week 4 Sex with HIV+ partner Stimulants Schooling (≥ 12y vs <12y) Race (Black vs White) Steady partner (Yes vs No) Text message (Yes vs No) ALL 3.28 1.78 2.23 -- Young 3.39 3.08 2.48 0.35 0.36 2.15

CONCLUSIONS HIV incidence rate 0.52/100PY (95%CI 0.13-2.06) Syphilis incidence 9.0/100PY (95%CI 6.5-12.5) Rectal chlamydia: ranged from 8.0% at enrollment to 7.7% at week 48 (p=0.90) Rectal gonorrhea: ranged from 4.9% at enrollment to 3.7% at week 48 (p=0.41) CONCLUSIONS Our results show high levels of retention and adherence to PrEP corroborating PrEP’s feasibility in real-world settings of a middle-income country Sexual behavior and STI incidence remained stable over time, suggesting a lack of risk compensation in this population