CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

724

Epidemiologic Burden of Hepatitis D Virus in the United States Elizabeth M Marlowe , Brooke E. Swanson, Susan E. Realegeno, Ron M. Kagan, William A. Meyer Quest Diagnostics, San Clemente, CA, USA Background: Hepatitis D affects nearly 5% of people globally who have a chronic infection with hepatitis B, according to the World Health Organization. The prevalence of hepatitis D virus (HDV) in the United States is generally considered lower than in other countries; however, HDV seroprevalence studies of the US population are limited, and reported ranges vary depending on the study population. To increase HDV detection, universal HDV testing of hepatitis B surface antigen (HBsAg)-positive specimens has been proposed. The objective of this study was to estimate the epidemiological prevalence of HDV infection within the United States in HBsAg-positive specimens. Methods: Consecutive unique deidentified remnant HBsAg positive specimens submitted from August to September 2023 for routine clinical testing at Quest Diagnostics, representing each of the ten Health and Human Services (HHS) regions in the United States, were included in the study. A reflex algorithm using HBsAg-positive specimens for HDV total antibody testing was utilized, and further testing of anti-HDV antibody positive-specimens for HDV RNA was conducted. Results: A total of 2,379 HBsAg-positive specimens were included in the study. The overall cohort was 46% female with a mean age of 50.1 years (50.8 years male, 49.4 years female). The overall seroprevalence of anti-HDV was 1.8%. The highest number of anti-HDV-positive specimens (n=8) were observed in HHS regions 3, 4, and 9, with prevalence (95% CI) of 0.031 (0.010-0.052), 0.017 (0.005-0.028) and 0.018 (0.006-0.030), respectively. Of the 42 anti-HDV positive specimens, 31% were also positive for HDV RNA (viral load range: 198 - 1,070,000 IU/mL: n=10; <40 IU/mL: n=3). Conclusion: These data suggest that HDV infection prevalence is relatively low in the United States. Further HDV seroprevalence studies are needed to determine which specific US regions would obtain the greatest benefit from future potential HDV-related interventions. Incidence and Outcome of HDV Infection in People With HIV in the Era of Tenofovir-Containing Therapy Yu-Shan Huang , Shu-Yuan Ho, Li-Hsin Su, Yi-Ching Su, Wen-Chun Liu, Hsin-Yun Sun, Wang-Hui Sheng, Szu-Min Hsieh, Yu-Chung Chuang, Sui-Yuan Chang, Chien-Ching Hung National Taiwan University Hospital, Taipei, Taiwan Background: Tenofovir-containing antiretroviral therapy (ART) achieves high rates of HBV suppression and improves survival among HBV-infected people with HIV (PWH). We investigated the incidence of HDV infection among HBV infected PWH and the impact of HDV on mortality and liver-related outcomes in the era of tenofovir-containing ART. Methods: HBV-infected PWH seeking HIV care at the National Taiwan University Hospital between 2011 and 2022 were included and followed until September 2023. Screening for anti-HDV antibodies was performed on an annual basis on sequentially archived blood samples collected from the included PWH. The timing of incident HDV infection was estimated by the midpoint between the last time point of blood samples tested HDV-seronegative and the first time point of samples tested HDV-seropositive. Comparisons of clinical outcomes between HBV-infected PWH with and those without HDV infection were analyzed using the Kaplan-Meier method and multivariate Cox proportional hazards models. Results: A total of 534 PWH who had chronic HBV infection were included and 36 (6.7%) tested seropositive for HDV at baseline. The median age of the included PWH was 37.8 years (IQR, 32.6-44.8) and 438 (82.0%) were men who have sex with men. Among the 498 PWH testing HDV-seronegative at baseline, 49 (9.8%) seroconverted for HDV, with 45 who were receiving tenofovir containing ART at the time of seroconversion. After a total of 3873.54 person years of follow-up (PYFU), the overall incidence rate of HDV superinfection was 12.65 per 1000 PYFU. After a median follow-up duration of 9.6 years (IQR 5.3 12.2), with 90.3% of the total follow-up time covered by tenofovir-containing ART, the all-cause mortality rate, liver-related mortality rate, and incidence of hepatocellular carcinoma (HCC) and cirrhosis were 4.7% (25/534), 0.9% (5/534), and 1.5% (8/534) and 2.6% (12/454), respectively (Figure). Using multivariate Cox proportional hazards models, HDV infection was associated with liver related mortality (adjusted HR 11.632, 95% CI: 1.380-98.041, p=0.024). The risks

whose post-treatment HCV sequence was different from baseline were defined as re-infection. Intermingling of sequences represented treatment failure. Re-infection rates were calculated using person-time of observation starting at the final reported date of SOF/VEL and ending at the earlier of HCV RNA >LLoQ or final study visit. Re-infection rates per 100 person-years (PY) were calculated with 95% confidence intervals constructed using Poisson distribution. Results: SVR in the primary analysis (intention to treat [ITT]) was 95% [95% CI 92.4-96.7] (379/399). Of 397 participants who had post-entry HCV RNA, 29 participants had HCV RNA >LLoQ and sequencing data available for re-infection analysis. Of these, six participants initially designated as non-SVR, and 11 participants initially classified as cured were determined to be HCV re-infections by phylogenetic analysis (total 17 re-infections). The SVR adjusting for re infection was 96.5% [95% CI 94.2-97.9] (385/399) compared to the ITT SVR of 95%. Of all participants, 17 had re-infection during 438 person-years of follow up (re-infection rate 3.9 per 100 PY [95% CI 2.4-6.2]). Of them, 12 were from HCV RNA collected at week 48 or 72. All 17 participants with HCV re-infection were assigned male sex at birth (13 endorsing MSM), 15 living with HIV, 14 had baseline genotype 1a, and 13 were from Thailand (of whom 11 were MSM with HIV and genotype 1a). Conclusion: Discounting re-infections, SVR observed in MINMON was 96.5%. The high HCV reinfection rate even prior to SVR, especially among MSM living with HIV underscores the need to scale-up evidence-based interventions to reduce re-infection while simultaneously increasing screening and treatment to minimize HCV viremic burden in the population. The figure, table, or graphic for this abstract has been removed. Impact of Healthcare Expenditure on HBV and HCV in Southern Western European Countries in 2000-2019 Claudia Palladino 1 , Rebeca Ramis 2 , Ifeanyi J. Ezeonwumelu 3 , Nuno Taveira 1 , Verónica Briz 2 1 Universidade de Lisboa, Lisbon, Portugal, 2 Institute of Health Carlos III, Madrid, Spain, 3 Gladstone Institute of Virology and Immunology, San Francisco, CA, USA Background: Viral hepatitis remains a threat to public health. This Global Burden Disease study was conducted to investigate the impact of the economic crisis that began in 2008 and which severely affected the Southern Western European (SWE) countries (Greece, Italy, Portugal, Spain), on the burden of HBV and HCV disease. Methods: Time series modelling was performed to quantify the impact of healthcare expenditure, defined as a percentage of gross domestic product, on the trend of the epidemiological estimates for HBV and HCV over the period 2000-2019. Estimates were retrieved from the Global Health Data Exchange of the Global Burden of Diseases 2019. Results: Mortality rates due to HBV stabilised in SWE during the period 2000 2019. Declining trends in incidence and prevalence of acute HBV and chronic HBV were observed in SWE, although the pace of decline was slower in the period 2010-2019. Acute HCV metrics and chronic HCV incidence and mortality showed a stable trend in SWE, whereas the prevalence of chronic HCV showed a fluctuating trend. Liver cancer due to both hepatitis infections showed a stagnating burden over time. An inverse association was observed between healthcare expenditure and both acute HBV and HCV infections, with results close to significance for acute HBV disability-adjusted life years (DALYs) [-2.54 (-5.09 – 0.01); p=0.05)] and years of life lost to premature mortality (YLLs) [-2.53 (-5.09 – 0.03); p=0.05)] in Greece. For acute HCV, the results showed that one unit (percentage) increase in healthcare expenditure was associated with a more beneficial effect on reducing incidence cases in Italy [-8.93 (-34.31 – 16.46); p=0.49], up to 80 times higher than in the other SWE countries. A similar inverse association between healthcare expenditure and cirrhosis and other chronic liver diseases (CCLD) metrics was found for both HBV and HCV, except for CCLD-HBV prevalence in Portugal and Spain. In addition, a positive but not significant association was found between healthcare expenditure and liver cancer metrics for both HBV and HCV. Conclusion: Epidemiological indicators for HBV and HCV showed a slower pace of decline in the period 2010-2019, with a better improvement for HBV and a stabilization of mortality and liver cancer burden due to both hepatitis. The economic crisis of 2008 had a negative impact on the burden of hepatitis B and C. Elimination of HBV and HCV by 2030 will be a major challenge in the SWE countries.

Poster Abstracts

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CROI 2024 213