CROI 2025 Abstract eBook

Abstract eBook

Poster Abstracts

Conclusions: These data support the paradigm that functional cure of HBV is not binary but represents a continuum of the quantity of HBsAg in plasma. This may partially explain why functional cure is gained (and lost) more often in PWHHB and that the phenomenon of occult HBV (in which HBV DNA is detected in plasma without HBsAg) may actually represent low level expression of HBsAg.

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Hepatitis B Reactivation PWH With Isolated Anti-Core Pattern on Therapies Excluding Tenofovir María del Mar Arcos-Rueda 1 , Alejandro de Gea Grela 2 , Luis Ramos 3 , Carmen Busca 2 , Rafael Mican 2 , Rocío Montejano Sanchez 3 , Maria Luisa Montes 2 , Jose Ignacio Bernardino 2 , Rosa De Miguel Buckley 2 , Jose R. Arribas 2 , Juan González García 3 , Luz Martín-Carbonero 3 1 La Paz University Hospital, Madrid, Spain, 2 Hospital La Paz Institute for Health Research, Madrid, Spain, 3 Hospital Universitario La Paz, Madrid, Spain Background: The isolated anti-core pattern (antiHBc+, antiHBs-, HBsAg-) is more frequently observed in people living with HIV (PWH). It suggests a past hepatitis B virus (HBV) infection; however, it can also indicate an occult HBV infection, which implicates a risk of viral reactivation. Historically, antiretroviral (ART) regimens containing tenofovir (TXF) have effectively suppressed HBV replication, reducing the risk of reactivation. However, dual HIV therapy regimens now commonly exclude TXF or other drugs with direct anti-HBV activity. The aim of this study was to evaluate the incidence of HBV reactivation in PWH with isolated anti-core pattern who are treated with dual ART regimens lacking TXF: DTG+3TC, DTG+RPV, or CAB+RPV-LA. Methods: Cross-sectional, single-center study including PWH with a history of isolated anti-core pattern who attended the HIV clinic between April and September 2024. All participants were on dual ART regimens without TXF. HBV serologies (antiHBc, antiHBs, HBsAg) and HBV-DNA levels were measured. Informed consent was obtained from all participants, and the study was approved by the Hospital La Paz Ethics Committee for Medical Research. Results are presented as absolute numbers (%) or medians (interquartile range, IQR). Results: Of 4219 PWH in our cohort, 9.8% (417) had an isolated anti-HBc pattern, and 32.6% (136) of them were on TXF-free ART regimens. The isolated anti-core pattern was confirmed in 77 of the 123 participants enrolled in the study (56 DTG+3TC; 13 DTG+RPV; 8 CAB+RPV-LA). The median age was 59 years (56-62), and 80% were male. The majority (96.7%) were Caucasian, and 81.6% had a history of cured hepatitis C infection. The median nadir CD4 count was 200 cells/mL (45-301), and the median duration on ART was 24 years (18-27). Among the 21 participants on regimens without HBV-active drugs, no cases of HBV reactivation were observed after a median time on the regimen of 3.6 years (1.1-4.6). The median duration of therapy with DTG+3TC was 3.6 years (2.4-4), and no HBV reactivation was detected in any participant. Only one participant (1/56) on DTG+3TC exhibited a transient HBV-DNA blip (29 IU/mL), which was not confirmed in a follow-up sample. Conclusions: Our findings suggest that the risk of HBV reactivation in PLHIV with isolated anti-core patterns who are treated with TXF-free dual ART regimens is extremely low after more than 3 years of follow-up. This holds true even for regimens that do not have direct anti-HBV activity, such as DTG+RPV and CAB+RPV-LA.

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HBsAg Seroclearance in HBV-Coinfected People With HIV in the Era of Tenofovir-Containing Therapy Chien-Ching Hung 1 , Yu-Shan Huang 2 , Hsin-Yun Sun 2 , Li-Hsin Su 2 , Yi-Ching Su 2 , Wen-Chun Liu 2 , Sui-Yuan Chang 3 1 National Taiwan General Hospital Yunlin, Yunlin, Taiwan, 2 National Taiwan University Hospital, Taipei, Taiwan, 3 National Taiwan University, Taipei, Taiwan Background: Long-term tenofovir-containing antiretroviral therapy (ART) achieves durable suppression of HIV and HBV, but its effect on functional cure of HBV infeciton in people with HIV (PWH) remains unclear. We aimed to determine the incidence of and factors associated with hepatitis B surface antigen (HBsAg) loss after treatment with tenofovir-containing ART in HBV coinfected PWH. Methods: Between 2011 and 2023, antiviral-naïve HBV-coinfected PWH seeking HIV care at the National Taiwan University Hospital and receiving tenofovir-containing ART as their initial antiretroviral regimen were retrospectively reviewed. HBV serologic markers and plasma HBV DNA were measured annually after ART initiation. Factors associated with HBsAg seroclearance were analyzed using the Kaplan-Meier method and Cox proportional hazards models. Clinical outcomes were compared between PWH with and those without HBsAg seroclearance. Results: A total of 161 HBV-coinfected PWH were enrolled. The median age of the included PWH was 36 years (range 31-41) and 142 (88.2%) were men who have sex with men. Sixteen (9.9%) PWH were born in the era of nationwide, universal neonatal HBV vaccination that has been implemented since July 1986. After a median of 7.8 years (range, 3.7-9.6) of follow-up, 15 (9.3%) PWH achieved HBsAg loss. Kaplan–Meier estimates showed that the cumulative incidence of HBsAg seroclearance was significantly higher in PWH born in the era of universal neonatal HBV vaccination and those with HBsAg ≤250 IU/mL (Figure). Using multivariate Cox proportional hazards models, being born in HBV vaccination era (adjusted hazard ratio [aHR] 14.756; 95% confidence interval [CI] 2.953 73.735, p =0.001) and havinr a baseline HBsAg level ≤250 IU/mL (aHR 9.027; 95% CI 2.640-30.871, p <0.001) were associated with HBsAg seroclearance after adjusting for age at enrollment, baseline CD4 count, plasma HBV DNA load, and HBeAg serostatus. None of the PWH with HBsAg seroclearance developed cirrhosis of the liver or hepatocellular carcinoma (HCC), while 7.8% and 1.4% of PWH without HBsAg seroclearance developed cirrhosis and HCC, respectively. Conclusions: In the era of tenofovir-containing ART, HBsAg seroclearance was uncommon in HBV-coinfected PWH. The statistically significant association between neonatal HBV vaccination history and HBsAg loss suggested that PWH who acquired HBV infection through horizontal transmission route may have a higher probability for functional cure of HBV infection.

Poster Abstracts

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HBV Reactivation Post-Switch to HBV-Inactive ART: A Scoping Review Kyle Ring 1 , Chloe Orkin 1 , Milosz Parczewski 2 , Marta Boffito 3 , Federico Garcia 4 , Anna Maria Geretti 5 1 Queen Mary University of London, London, UK, 2 Pomeranian Medical University, Szczecin, Poland, 3 Chelsea and Westminster NHS Foundation Trust, London, UK, 4 Hospital Universitario San Cecilio, Granada, Spain, 5 University of Rome Tor Vergata, Rome, Italy Background: HBV reactivation in people living with HIV and evidence of past HBV infection is an important consideration when evaluating the risk/benefit of discontinuing HBV-active ART in favor of other treatment regimens. We aimed to summarize available evidence on reactivation risk after switching to HBV inactive regimens, and to identify predictors that may guide clinical practice.

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