CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

using high-sensitivity ELISA. IL-6 levels were analyzed using Mann-Whitney tests and linear regression adjusted for potential confounders in R studio. Results: A total of 118 patients with available week 0 and 48 plasma samples were included; 17% women, mean age 44 ± 11 years, 79% white, 62% MSM, 9% with past AIDS diagnosis, median nadir CD4 338 cells/uL, baseline CD4 counts 776/uL, median duration of HIV suppression 5.2 years, median IL6 levels within normal range (0.96 pg/mL [0.53-1.44]). No differences were observed in the general characteristics between groups. No significant differences in IL-6 changes were observed between groups from week 0 to 48 (median fold change for DTG/3TC, 1.1 [0.7-1.7]; for BIC/FTC/TAF, 1.2 [0.8-1.8], P = 0.688)(Figure 1). Multivariate linear regression analyses corroborated these findings (Coef -0.07, P = 0.931). Conclusion: This analysis revealed no significant impact on IL-6 levels when switching from DTG/3TC to BIC/FTC/TAF after 48 weeks. These preliminary findings suggest a neutral inflammatory effect for the ART switch, warranting further study to elucidate the longer-term influence on inflammation.

We evaluated the efficacy and safety of switching older adults from a first-line regimen to bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF). Methods: The B/F/TAF-elderly study is an open-label, randomized, active controlled, non-inferiority trial conducted at two sites in Kenya. Participants include HIV-1 positive older adults (≥60 years) on any first line regimen with HIV RNA <50 copies/mL for at least 12 weeks prior to enrolment and randomized 1:1 to switch to B/F/TAF or continue current ARV regimen (CAR). The co-primary endpoints are proportion of participants with HIV-1 RNA ≥50 copies/mL at week 48 in the intention-to-treat-exposed population using FDA Snapshot algorithm with a non-inferiority margin of 4%, and mean percentage change in lumbar spine bone mineral density (BMD) from baseline to week 48. The trial is continuing to week 96. ClinicalTrials.govNCT0524360 Results: Between Feb and May 2022, 520 participants were randomized and received treatment (260 B/F/TAF, 260 CAR). Of these, 296 were enrolled in the BMD monitoring population (143 B/F/TAF, 153 CAR). All participants were black, median age 64 years (range 60-80), 267 (51%) were female, with baseline characteristics balanced between arms. At baseline, 495 (95%) participants were on tenofovir disoproxil fumarate (TDF) and 177 (60%) of the BMD population had osteoporosis. At week 48, 5/260 participants (1.9%) in the B/F/TAF arm and 7/260 (2.7%) in the CAR arm had HIV-1 RNA ≥50 copies/mL (difference [95% CI], -0.8% [-3.4 to 1.8]), meeting non-inferiority criteria (Figure 1A). No participant with protocol defined virologic failure met the threshold for drug resistance testing of ≥500 copies/ml. The mean percentage change in lumbar spine BMD was +2.17% (SD 5.23) in the B/F/TAF arm and +0.61% (SD 5.44) in the CAR arm (difference [95% CI], 1.56 [0.32 to 2.79], p=0.014, Figure 1B). Grade 3 or 4 adverse events (AEs) were uncommon (3.1% on B/F/TAF; 2.3% on CAR) with no treatment-related serious AEs. Participants discontinuing study drug due to any AE was 1 (0.4%) on B/F/TAF and 15 (5.8%, all due to declining kidney function) on CAR. Conclusion: Switching to B/F/TAF may be effective and safe for virally suppressed adults ≥60 years on a TDF containing regimen and is associated with improvement in BMD and fewer requirements for regimen modification due to worsening kidney function. Impact of Switching From Dual to Triple Therapy on Inflammation: INSTINCT Study Sergio Serrano-Villar 1 , Laura Martín-Pedraza 1 , Carmen Busca 2 , Juan Manuel Tiraboschi 3 , Jesús Santos 4 , Luis Fernando López-Cortés 5 , Carmen Hidalgo Tenorio 6 , Vicente Estrada 7 , María José Crusells Canales 8 , Alfonso Cabello Úbeda 9 , Alberto Díaz de Santiago 10 , María Novella 11 , Miguel Torralba 12 , Marta De Miguel 13 , Santiago Moreno 1 1 Hospital Ramón y Cajal, Madrid, Spain, 2 La Paz University Hospital, Madrid, Spain, 3 Hospital Universitario de Bellvitge, Barcelona, Spain, 4 Hospital Virgen de la Victoria, Málaga, Spain, 5 Hospital Universitario Virgen del Rocio, Sevilla, Spain, 6 University Hospital Virgen de las Nieves, Granada, Spain, 7 Hospital Universitario Clí¬nico San Carlos, Madrid, Spain, 8 Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain, 9 Fundacion Jimenez Diaz, Madrid, Spain, 10 Hospital Puerta de Hierro, Madrid, Spain, 11 Hospital Universitario Príncipe de Asturias, Madrid, Spain, 12 Hospital Universitario de Guadalajara, Guadalajara, Spain, 13 Fundación SEIMC-GeSIDA, Madrid, Spain Background: Because inflammation is associated with mortality and has been linked to HIV transcription in lymphoid tissues during ART, it is necessary to address the long-term effects of switching ART regimens with different numbers of antiretrovirals on inflammation. Methods: In this interim analysis of the randomized, open-label, multicenter INSTINCT trial (clinicaltrial.gov: NCT04076423), we evaluated the effect of switching from DTG/3TC to BIC/FTC/TAF vs. remaining on DTG/3TC on systemic inflammation up to 48 weeks. Participants were adults with confirmed, virologically suppressed HIV, on stable ART with DTG/3TC for a minimum of 48 weeks. Exclusions included previous virological failure, drug resistance, and autoimmune conditions. We focused on IL-6 changes from baseline to week 48

Poster Abstracts

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Switching to DTG+3TC vs 3-Drug Regimens in Routine Clinical Care: Long-Term Swedish Data Erik Sörstedt 1 , George Nduva 2 , Saara Hiltunen 3 , Johanna Repits 2 , Fredrik Månsson 4 , Åsa Mellgren 1 , Eva Fernvik 5 , Adam Stubbs 5 , Melanie Schroeder 5 , Johanna Brännström 6 , Christina Carlander 6 1 University of Gothenburg, Gothenburg, Sweden, 2 GlaxoSmithKline, Stockholm, Sweden, 3 BCB Medical, Stockholm, Sweden, 4 Lund University, Lung Sweden, 5 ViiV Healthcare, Brentford, United Kingdom, 6 Karolinska Institute, Stockholm, Sweden Background: Swedish HIV treatment guidelines recommend that switching to the 2-drug regimen dolutegravir (DTG) + lamivudine (3TC) for maintaining virologic suppression should be considered in people living with HIV (PLHIV) in routine clinical care. We assessed long-term outcomes of switching to DTG+3TC (vs 3-drug regimens, 3DR) in virologically suppressed individuals in Sweden. Methods: Retrospective data of all ART-experienced PLHIV with HIV RNA <50 copies/ml and switching to either DTG+3TC or any 3DR were obtained from the Swedish National Quality Registry for HIV (InfCareHIV). Within-group precision rates for virological failure (VF, having two consecutive HIV RNA levels ≥200 copies/mL prior to/by assessment timepoint) were determined for DTG+3TC and 3DR groups at months M6, M12, M24, M36, and M42 post-switch. A logistic generalized estimating equations (GEE) model was used to find associations between patient demographic and clinical predictors on VF. Results: 2461 PLHIV switched regimen between July 2019 – May 2023; 1125 (46%) to DTG+3TC and 1336 (54%) to 3DR. The mean estimated time of extended exposure was 17.4 and 23.7 months for DTG+3TC and 3DR groups, respectively. 1778 PLHIV had data at M6, M12 (n=1418), M24 (n=985), M36 (n=444), and M42 (n=174). 37 on 3DR met VF – versus seven on DTG+3TC. VF rates for DTG+3TC group were 0.0013 (95% CI 0.0002, 0.009) at M6, and 0.0036 (0.0009, 0.014) at M12, 0.003 (0.0005, 0.02) at M24, 0.018 (0.005, 0.07) at M36, and 0.029 (0.004, 0.2) at M42. VF rates for 3DR group were 0.003 (0.001, 0.009) at M6, 0.014 (0.008, 0.024) at M12, 0.018 (0.01, 0.031) at M24, 0.021 (0.01, 0.044) at M36, and 0.023 (0.009, 0.061) at M42. In a GEE model (adjusting for treatment, ART adherence, time, sex, age, baseline CD4, HIV subtype, baseline drug resistance mutations, HBV, and HCV serostatus, viral blips before baseline and during the study), male sex, and CD4 count ≥500 at baseline were significantly associated with decreased risk of VF (adjusted odds ratio 0.41 [0.19–0.86], p=0.019, and 0.28 [0.14–0.59], p=0.001, respectively). Viral blips post-switch, and suboptimal adherence were significantly associated with increased risk of VF (4.84 [2.45–9.589], p<0.001, and 3.72 [1.12–12.34], p=0.032, respectively). Conclusion: In this long-term real-world retrospective study, no significant difference in the risk of VF between DTG+3TC and 3DR were found. These

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