CROI 2025 Abstract eBook

Abstract eBook

Poster Abstracts

Conclusions: SD and HD vaccination drive strong, transient responses to flu antigens. Old individuals and PWH have decreased H1 responses. Our data indicate that HD vaccine demonstrates limited efficacy in further enhancing immune responses of older PWH.

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Persistence of Seroprotection After Modified Hepatitis B Vaccine Schedule in People Living With HIV Caroline Troccoli 1 , Denise V. Potsch 1 , Pietra S. Nascimento 1 , Cristina B. Hoffer 1 , Paulo F. Barroso 1 , Juliana Miguel 2 , Livia Villar 2 1 Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil, 2 Oswaldo Cruz Institute – Fiocruz, Rio de Janeiro, Brazil Background: To evaluate the persistence of seroprotection, anti-HBs titers, and anamnestic response to challenge dose, following the Brazilian Ministry of Health's (MS) recommended HBV vaccination schedule in people living with HIV/ AIDS (PLHIV). Methods: Intervention study in PLHIV followed up in the outpatient clinics of the Infectious disease department at Federal University Hospital in Rio de Janeiro, who achieved seroprotection (anti-HBs ≥ 10mIU/mL) with the primary anti-HBV vaccination (4 doses of 40 µ g), in the original study between 2006 2010. In the current study (2021-2022), a blood sample was obtained prior to immunization, and one dose (40 µ g) of the anti-HBV vaccine was administered shortly thereafter. A second sample was taken between one and six months after immunization. Seroprotection and antibody titers were assessed in both samples using commercial eletrochemiluminescence assays for HBsAg, anti-HBc and anti-HBs. Individuals who received additional doses of HBV vaccine during the period were excluded. Results: 75 of the 148 PLHIV in the original study participated (51%), 44% men, median interval between studies 14 years, age 53 years (36-75) and CD4 774 cells/mm³ (257-1936), 100% on ART and 99% with undetectable HIV viral load. In the pre-immunization sample, seroprotection was demonstrated in 80% of individuals with anti-HBs titers between 10-99 mIU/mL (33%); ≥100-999 mIU/mL (37%) and ≥1000 mIU/mL (10%). In post-immunization samples, seroprotection was demonstrated in 96% of individuals with anti-HBs titers between 10-99 mIU/mL (4%); ≥100-999 mIU/mL (12%) and ≥1000 mIU/mL (80%) (p<0.01). A significant decrease in anti-HBs titers was observed between studies (baseline and current, p<0.01) and a significant increase in titers between pre- and post-immunization samples (p<0.01). The time interval between the challenge dose and the post-immunization sample did not affect anti-HBs titers (p=0.62). Markers of HBV infection (anti-HBc and HBsAg) were non-reactive in all participants. Conclusions: The scheme recommended by the Ministry of Health for vaccinating PLHIV against HBV resulted in sustained seroprotection for more than a decade. Even with the natural decline of antibodies, the use of a challenge dose was able to restore anti-HBs titers to the values obtained in the previous study. This ensures that it is the best scheme in the primary response to vaccination, and important in the generation of lasting immunologic memory. Delayed HIV-1 Rebound Correlates With Enhanced CD8+ T-Cell Activation in Human Trials Rasmi Thomas 1 , Philip Ehrenberg 1 , Gautam Kundu 2 , Daina Eiser 2 , Timothy Ezebuiro 2 , Carlo Sacdalan 3 , Somchai Sriplienchan 3 , Nittaya Phanuphak 4 , Sandhya Vasan 5 , Ashan Dayananda 5 , for the RV254 Study Team 1 US Military HIV Research Program, Bethesda, MD, USA, 2 Walter Reed Army Institute of Research, Silver Spring, MD, USA, 3 SEARCH, Bangkok, Thailand, 4 Institute of HIV Research and Innovation, Bangkok, Thailand, 5 Henry M Jackson Foundation, Bethesda, MD, USA Background: Antiretroviral therapy (ART) is an effective treatment for people living with HIV (PLWH) that can suppress the virus and prevent disease progression. However, the virus persists latently and rebounds in a majority

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Herpes Zoster Reactivation in a Cohort of People Living With HIV Vaccinated With Recombinant Vaccine Stefania Arsuffi 1 , Luca Rossi 1 , Fabio Riccardo Colombo 1 , Elisa Mirovic 2 , Miriam Inverardi 1 , Davide Laurenda 1 , Ilaria Izzo 2 , Deborah Castelli 2 , Francesca Gaffurini 2 , Itala Polesini 2 , Giorgio Tiecco 1 , Francesco Castelli 1 , Stefano Calza 1 , Eugenia Quiros-Roldan 2 , Emanuele Focà 1 1 University of Brescia, Brescia, Italy, 2 ASST Spedali Civili di Brescia, Brescia, Italy Background: People living with HIV (PLWH) have a higher risk of herpes zoster (HZ) reactivation and postherpetic neuralgia (PHN) compared to general population. Our study aims to evaluate prevalence of HZ reactivation and PHN after vaccination with recombinant vaccine in a population living with HIV, and to identify risk factors associated with recurrence. Methods: We conducted a prospective, observational, monocentric, cohort study, enrolling all the patients of at least 18 years of age who were vaccinated with recombinant vaccine for HZ (RZV) from January 2022 to December 2023. A questionnaire was proposed to all the subjects at least 6 months after vaccination, inquiring about previous history of HZ and PHN, and recurrence after vaccination. Moreover, we collected data regarding demographic characteristics, comorbidities, concomitant medication, viro-immunological status and antiretroviral (ARV) regimens. We performed a descriptive analysis and univariate logistic regressions to investigate associated risk factors. Results: We included 223 subjects (population characteristics are described in Table 1). We estimated the prevalence of events in a subgroup of 145 subjects with complete data: in particular, we recorded 54 subjects with pre-vaccination HZ (prevalence 37.24% [95%CI: 29.36% - 45.65%]) and 13 with post-vaccination HZ (prevalence 8.97% [95%CI: 4.86% - 14.84%]). The prevalence of pre vaccination postherpetic neuralgia was 19.23% [95%CI: 11.18% - 29.73%], with mean NRS 6.33 [95%CI: 4.9 - 7.76]; no case of postherpetic neuralgia was recorded after vaccination. Evaluating risk factors related to post-vaccination HZ, we didn’t find any association with current levels of HIV-RNA, CD4+ cell count, and CD4+/CD8+ ratio, duration of HIV infection, nadir of CD4+ cell count, previous AIDS-defining events or concomitant medications. We found a correlation between HZ and age (OR 1.06, 95%CI 1.01-1.13, p-value 0.031), hematological (OR 9.60, 95%CI 1.70-49.9, p-value 0.007), oncological (OR 5.36, 95%CI 1.04-22.8, p-value 0.028) and hepatic comorbidities (OR 3.67, 95%CI 1.10-12.0, p-value 0.030). Conclusions: Overall, this is the first real-world study that highlights the excellent clinical response to HZ vaccination, with a low prevalence of HZ reactivation and complete resolution of postherpetic neuralgia after the vaccination. Moreover, we identified clinical conditions promoting the recurrence HZ after vaccination.

Poster Abstracts

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CROI 2025 121