CROI 2020 Abstract eBook

Abstract eBook

Poster Abstracts

Pittsburgh, PA, USA, 4 Northwestern University, Chicago, IL, USA, 5 Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA Background: Erectile dysfunction (ED) drugs are frequently used in men who have sex with men (MSM). Although commonly associated with increased vasodilation, there is evidence of beneficial immunomodulatory effects of these drugs in animal studies. However, studies on the effect of ED drugs on immune capacity and function in MSM are limited. Methods: A total of 1,391 HIV positive men and 307 HIV negative men were included from the Multicenter AIDS Cohort Study (MACS), an ongoing prospective HIV/AIDS cohort study in the U.S., from 1998 onwards, with ages ranging from 19 to 70 years. We used marginal structural models in the form of g-computation in complex longitudinal setting to assess the causal mean differences (MD) in CD4 and CD8 T cells for 10 years, as well as other immune biomarkers up to 4 observations. Results: ED drug use over time was associated with an increase in the number of CD4 cells in HIV positive men. After controlling for important confounding variables such as age, viral load and ART, the causal MD in CD4 cell counts in HIV positive men after 1 year of ED drug use was 57.6 cells/µL and increased to 117.7 cells/µL after 10 years. CD8 cell counts were higher among ED drug users over a 10-year period compared to non-users in the HIV positive group but showed almost no significant differences in HIV negative group. HIV positive ED drug users also showed reduced levels of pro-inflammatory markers, IL-6 (MD: -1.98, 95% CI = -2.22 – -1.75) and TNF-α (MD: -2.31, 95% CI: -2.48 – -2.14) after one year of observation. An anti-inflammatory cytokine, IL-10, was higher in ED drug users compared to non-users. HIV negative subjects showed similar effects with ED drug use over time with respect to inflammatory markers. Conclusion: ED drug use was associated with a significantly higher CD4 T cell outcome in HIV positive MSM. Furthermore, analyses of immune biomarkers showed ED drug use to have been associated with lower pro-inflammatory and higher anti-inflammatory markers over time. This observation suggests a favorable immunomodulatory effect of ED drugs in MSM. 878 PREEXPOSURE PROPHYLAXIS ADHERENCE AND PERSISTENCE IN KENYAN TRANSGENDER WOMEN AND MSM Makobu Kimani 1 , Elisabeth M. van der Elst 1 , Oscar Chirro 1 , Fauz Ibrahim 2 , Nana Background: Transgender women (TGW) and men who have sex with men (MSM) in sub-Saharan Africa have high HIV acquisition risks and can benefit from daily pre-exposure prophylaxis (PrEP) if taken regularly. We set out to assess PrEP adherence by measuring tenofovir-diphosphate (TFV-DP) levels and explore motives for PrEP persistence in a sample of TGW and MSM in coastal Kenya. Methods: Participants enrolled in a one-year PrEP programme and made quarterly visits irrespective of whether they were still using PrEP. At their month 6 visit, participants provided a dried blood spot to be tested for TFV-DP levels; protective levels were defined as those compatible with ≥4 pills per week (700-1249 fmol/punch). Before TFV-DP levels were available, sub-set of these participants completed in-depth interviews (IDIs). All TGW and purposively selected MSM participated in the IDIs. We used semi-structured topic guides to explore motives to start and adhere to PrEP, and reasons to stop it. IDI data were analyzed thematically. Results: Fifty-three participants (42 MSM and 11 TGW) were enrolled. At month 6, 12 (22.6%) participants (9 MSM and 3 TGW) were lost to follow up. Any TFV-DP was detected in 62.5% (5/8) of TGW vs. 15.2% of MSM (5/33, p=0.004). Protective levels were detected in 37.5% of TGW (3/8) but not in any MSM. Nineteen IDIs were conducted, with 7 TGW and 8 MSM on PrEP, and 1 TGW and 3 MSM off PrEP. Unplanned or frequent risky sexual risk behaviour, including condomless anal intercourse, were the main motives for PrEP uptake. Among TGW, the notion that PrEP reinforced their female gender identity seemed to aid adherence. Inconsistent PrEP use was attributed to situational factors and included illness, concomitant drug use, travel, and less sexual satisfaction. Motives to discontinue PrEP included negative reactions from partners, experience of side-effects, and change in risk taking behaviour. Conclusion: Although 1 in 5 participants were lost to follow up, almost 40% of TGWwere protected by PrEP. MSM appear to have greater challenges adhering to PrEP. TGW appeared to have had more agency to take PrEP. Personal and Mukuria 1 , Tobias F. Rinke de Wit 3 , Susan M. Graham 4 , Eduard Sanders 1 1 KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya, 2 Kilifi County Department of Health, Kilifi, Kenya, 3 Academic Medical Center, Amsterdam, Netherlands, 4 University of Washington, Seattle, WA, USA

876 PREDICTIVE VALUE OF THE CD8 COUNTS AND CD4/CD8 RATIO AT 2 YEARS OF SUCCESSFUL ART Sergio Serrano-Villar 1 , Kunling Wu 2 , Peter W. Hunt 3 , Judith J. Lok 2 , Talía Sainz 4 , Santiago Moreno 1 , Steven G. Deeks 1 , Ronald Bosch 2 1 Hospital Ramón y Cajal, Madrid, Spain, 2 Harvard T.H. Chan School of Public Health, Boston, MA, USA, 3 San Francisco General Hospital, San Fransisco, CA , USA, 4 La Paz University Hospital, Madrid, Spain Background: While increased CD8+ T cell counts and low CD4/CD8 ratio during treated HIV CD4/CD8 ratio correlate with immunosenescence, cohort studies have yielded conflicting results on its additional predictive value to identify HIV-infected individuals at higher risk of clinical events. Methods: We selected treatment-naive individuals initiating ART from ACTG studies 384, 385, A5095, A5142, A5202 and A5257 who had achieved viral suppression at year 2. We examined the effect of CD4/CD8 at year 2 on the probability of AIDS and serious non-AIDS events in years 3-7, using A5001 long-term follow-up. We examined different CD8+ T cells and CD4/CD8 ratio categorizations. We used inverse probability weighting methods to address informative censoring, combined with multivariable logistic regression models. Results: Among 5133 participants who met our inclusion criteria, 961 reached year 7 while on suppressive ART, and 3787 (74%) were censored due to treatment failure, ART discontinuation or drop-off. 385 had a clinical event during years 3-7. At ART initiation, the median age was 38 years, 959 (19%) were female, 2168 (42%) were white, 407 (8%) reported current or previous IDU; year 2 median CD4 counts 503 cells/uL (348-668), CD8 counts 772 cells/uL(578-1022), CD4/CD8 ratio 0.65 (0.41-0.95). Adjusted odds ratios indicated that CD8+ T cell counts had the clearest stepwise effect across the full range of values for the association with clinical events at the different cut-offs. CD4/CD8 ratio was also predictive of greater risk of events through year 7 at extremely low values (Table 1). The estimated probability of an event in years 3-7 was 30% among participants with CD4/CD8 ratio <0.15 and 15% among those ≥0.15 (P=0.001). Sensitivity analyses did not reveal major differences when restricting to infectious vs. non-infectious events or AIDS vs. non-AIDS events. Conclusion: The results of this analysis with pooled data from clinical trials support the value of the CD8+ T cell count as a predictor of clinical progression. People with very high CD8 counts during suppressive ART might benefit from closer monitoring and may be a target population for novel interventions.

Poster Abstracts

877 EFFECT OF ERECTILE DYSFUNCTION DRUGS ON T CELLS AND IMMUNE MARKERS IN MEN Jee Won Park 1 , Adrian Dobs 2 , Ken Ho 3 , Frank J. Palella 4 , Eric C. Seaberg 5 , Onyebuchi A.Arah 1 , Otoniel Martínez-Maza 1 , Roger Detels 1 1 University of California Los Angeles, Los Angeles, CA, USA, 2 Johns Hopkins University School of Medicine, Baltimore, MD, USA, 3 University of Pittsburgh,

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