CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

1044 Temporal Trends in CD4 Cell Count Soon After Seroconversion and HIV-RNA Viral Set-Point Nikos Pantazis 1 , Dominique Costagliola 2 , Ard van Sighem 3 , Inma Jarrin 4 , Laurence Meyer 5 , Caroline Sabin 6 , Christina Carlander 7 , John Gill 8 , Shema Tariq 6 , Bruno Spire 9 , Fiona Burns 6 , Elisa Ruiz-Burga 6 , Kholoud Porter 6 , Giota Touloumi 1 , for the CASCADE Collaboration 1 National and Kapodistrian University of Athens, Athens, Greece, 2 Sorbonne Université, Paris, France, 3 Stichting HIV Monitoring Foundation, Amsterdam, Netherlands, 4 Institute de Salud Carlos III, Madrid, Spain, 5 Université Paris-Saclay, Paris, France, 6 University College London, London, United Kingdom, 7 Karolinska University Hospital, Stockholm, Sweden, 8 Southern Alberta Clinic, Calgary, Alberta, 9 Aix Marseille Université, Marseille, France Background: We have previously reported on a temporal decrease in CD4 cell count at seroconversion (SC) and an increase in HIV-RNA viral load (VL) levels at 1 year (which we refer to as set-point) over the period 1980-2008. These markers of virulence reached a plateau in the mid 2000's. Here we update these analyses, focusing on changes since the introduction of combination ART in 1996. Methods: Data were derived from the CASCADE Collaboration. Included individuals seroconverted ≥1996, were ≥16 years, had an HIV- to HIV+ test interval ≤1 year or other laboratory evidence of SC, and CD4/VL measurements while ART naïve and AIDS-free. Exploratory analysis revealed gradient changes at ~4 months and ~1 year after SC for CD4 and VL, respectively. Analyses were based on piecewise linear mixed models. Calendar time effects were introduced through natural cubic splines. For CD4 at 4 months after SC and viral set-point analyses, those seroconverting after 1/1/2015 and 1/1/2014, respectively, were excluded, as they tended to initiate ART very soon after SC and reliable estimation of these quantities was not feasible. Models were adjusted for age, sex, transmission mode, region of origin, acute infection (< or ≥30 day HIV test interval) and type of viral assay. Results: Of 28556 individuals in CASCADE, 15059 (52.7%) fulfilled the inclusion criteria. The majority (70.5%) acquired HIV through sex between men and 10.3% men and 14.3% women through heterosexual contact. Median (IQR) age at SC was 33 (27, 41) years. Of 2701 with known subtype 2275 (84.2%) had a B subtype. Estimated (95% CI) CD4 cell count levels at 4 months after SC declined from 598 (562-635) for those seroconverting in 1996, to a plateau of ~559 (530-588) cells/μl for those seroconverting between 2006 and 2010 and slowly increased in more recent years (Figure, a). Viral set-point showed a similar but reversed trend with an increase from 4.31 (4.17-4.44) in 1996 to ~ 4.47 (4.36 4.58) log c/mL in 2006-2010 and a slow declining trend thereafter (Figure, b). Individuals with CRF02_AG subtype had approximately 62 cells/μl lower CD4 cell count at 4 months after SC (p=0.023) and all non-B subtypes were associated with non-significantly lower viral set-point compared to those with B subtype. Conclusion: Our results showed minimal changes in levels of both CD4 soon after SC and viral set-point after 2004 suggesting that these markers of HIV virulence may have plateaued.

prevent and manage AHD require an understanding of where the care cascade is failing. We analysed data from a series of studies in southern and east Africa, describing characteristics of individuals presenting with AHD between 2015 and 2021. Methods: We compared demographics and ART status in i) a cryptococcal antigen screening program in Botswana with CD4 counts<100 cells/μL in 2015/16; (ii) a similar cohort recruited in 2018/19 after universal ART introduction; and (iii) the multi-country AMBITION trial of cryptococcal meningitis conducted 2018/2021. Results: 1645 individuals were included in the 2015/16 cohort, 743 in the 2018/19 cohort, and 810 in the AMBITON trial. Median age, sex and CD4 counts were similar (37, 39, and 37 years; 50%, 55%, and 61% male; 54 cells/μL, 59 cells/μL, and 27 cells/µL). In the 2015/16 cohort 55% (911/1645) of individuals presenting with AHD were ART naïve; 40% (654/1645) had been newly diagnosed with HIV and 16% (257/1645) knew their HIV status but had not initiated treatment; 45% (734/1645) were ART experienced (either taking or previously taken ART). By 2018/19 and 2018/2021 individuals presenting with AHD were significantly more likely to be ART experienced (67% (499/743) and 64% (521/810), p<0.001). In the most recent AMBITION trial, of the 521 ART experienced patients, 14% (72/521) had initiated ART within the last 2 weeks, 23% (119/521) between 2 weeks and 6 months, 40% (207/521) had been on ART for over 6 months, and 24% (123/521) had started ART but discontinued after a median of 61 months (IQR 36-112); of those on ART for over 6 months, 31% (64/207) reported poor adherence and 88% (161/184) of those with viral load results available had a non-suppressed viral load. Conclusion: The proportion of AHD due to late HIV diagnosis and ART initiation has declined since the introduction of universal treatment in 2016, with most people with AHD now presenting having previously initiated ART. In addition to ongoing AHD presentations due to delayed HIV testing and ART initiation or default from care, a substantial proportion of AHD is occurring in individuals in care, who have either recently initiated or re-initiated ART with low CD4 counts, or who are experiencing treatment failure due to adherence or resistance issues, reflecting the cyclical nature of the care cascade. 1046 Global Trends in CD4 Count Measurement and Prevalence of CD4 <200 cells/μL at ART Initiation Renee De Waal 1 , Kara Wools-Kaloustian 2 , Ellen Brazier 3 , Keri N. Althoff 4 , Antoine Jacquet 5 , Stephany Duda 6 , Nagalingeswaran Kumarasamy 7 , Helen Byakwaga 8 , Gad Murenzi 9 , Amy C. Justice 10 , Didier Koumavi Ekouevi 11 , Carina Cesar 12 , Mark Pasayan 13 , Reshma Kassanjee 1 , for International epidemiology Databases to Evaluate AIDS 1 University of Cape Town, Cape Town, South Africa, 2 Indiana University, Indianapolis, IN, USA, 3 City University of New York, New York, NY, USA, 4 The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA, 5 University of Bordeaux, Bordeaux, France, 6 Vanderbilt University, Nashville, TN, USA, 7 VHS – Infectious Diseases Medical Centre, Chennai, India, 8 Mbarara University of Science and Technology, Mbarara, Uganda, 9 Rwanda Military Hospital, Kigali, Rwanda, 10 VA Connecticut Healthcare System, West Haven, CT, USA, 11 L'Université de Lomé, Lomé, Togo, 12 Fundación Huésped, Buenos Aires, Argentina, 13 Research Institute for Tropical Medicine, Manila, Philippines Background: Since the 'Treat-All' era, people with HIV (PWH) start antiretroviral therapy (ART) regardless of CD4 count; consequently, CD4 measurement at ART initiation is declining in many countries. However, CD4 counts are still necessary to identify people with advanced HIV disease, to monitor and evaluate ART programs, and to inform epidemiological models. We described CD4 availability and prevalence of CD4 <200 cells/µL at ART initiation using observational data from a global HIV cohort collaboration, the International epidemiology Databases to Evaluate AIDS (IeDEA). Methods: We included PWH who initiated ART at age 15–80 years during 2005–2019. We excluded those with HIV viral load <1000 copies/mL at ART start (assumed treatment-experienced). We described proportions of PWH with available CD4 (measured within 6 months before to 2 weeks after ART start); and among those with a CD4, those with CD4 <200 cells/µL; by year of ART start, region, age, and birth sex. Results: We included 1, 355, 104 PWH from 8 regions (Asia-Pacific: 24, 446, Latin America: 33, 243, North America: 51, 469, East Africa: 236, 981, West Africa: 37, 956, Central Africa: 51, 667, Southern Africa excluding South Africa: 602, 948, South Africa: 316, 394); 63% were female. Median (interquartile range, IQR) age at ART start was 37 (31–44) in men and 32 (26–39) in women. Across regions, CD4 availability was 58–86% in 2005, and 48–87% in 2015. By 2019, it remained between 61–86% in North America, Latin America, Asia-Pacific, and South Africa; but declined to 13–53% in other participating sub-Saharan

Poster Abstracts

1045 Advanced HIV Disease and the Care Cascade: Trends From 2015-2021 David S Lawrence 1 , Melanie Moyo 2 , Mark W. Tenforde 3 , Kwana Lechiile 4 , Charles Muthoga 4 , Tshepo B. Leeme 4 , Thomas S. Harrison 5 , Madisa Mine 6 , Joseph N. Jarvis 1 , for the AMBITION Study Group 1 London School of Hygiene & Tropical Medicine, London, United Kingdom, 2 University of Malawi, Blantyre, Malawi, 3 University of Pennsylvania in Botswana, Gaborone, Botswana, 4 Botswana Harvard AIDS Institute Partnership, Gabarone, Botswana, 5 St George's University of London, London, United Kingdom, 6 National Health Laboratory, Gaborone, Botswana Background: The burden of advanced HIV disease (AHD) remains high in much of Africa despite expanded access to ART. Designing interventions to effectively

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