{ "abstract": "Background Integrase strand transfer inhibitor (INSTI)-based antiretroviral therapy (ART) is recommended as first-line treatment for people with HIV (PWH). However, long-term real-world data on therapeutic stability, switching strategies, and immuno-virological outcomes in ART-naïve patients presenting with advanced HIV disease (AHD) remain limited. This study evaluated treatment dynamics and 5-year immuno-virological outcomes from HIV diagnosis in AHD PWH.Methods Multicentre observational study across five Italian centres including ART-naïve PWH with AHD diagnosed in 2019-2024 ( table 1). ART regimens and classes were recorded at treatment initiation (T0) and after 1, 2, 3, 4, and 5 years (T1–T5). CD4 count and HIV-RNA were assessed across visits. Treatment durability, switching patterns, and outcomes were analysed according to ART class.Results At T0, 224 PWH were enrolled, 54% AIDS presenters. Treatment initiation data were available for 220 participants; 4 did not start ART. INSTI-based regimens predominated at all timepoints (87-96%). Overall, 90.0% initiated INSTI; among them, three-drug regimens (3DR) were used in 97.6% (203/208) and two-drug regimen (2DR) in 2.4% (5/208). BIC/F/TAF was the most common initial regimen (64%, 140/219). The Sankey diagram showed high INSTI persistence over time ( figure 1), with most participants remaining on across timepoints. A substantial proportion of individuals were lost to follow-up (LTFU) at each interval, progressively reducing the number under observation. After 5 years, 30.3% were 2DR and 68.2% on 3DR.CD4 counts increased progressively over follow-up in all cART initiation groups. In the INSTI group, median CD4 rose from 50.0 cells/mm3 at baseline to 465.5 at T5 and 347.0 at last follow-up; in the PI/b group, values increased from 36.5 to 413.0 and 324.0 cells/mm3, respectively. CD4 trajectories were broadly comparable across regimens, with no significant differences at any timepoint (figure 2A). Baseline viral load was comparable across cART initiation groups (median 302,449.5 INSTI vs 86,313.5 NNRTI vs 169,195.0 PI/b copies/mL; p=0.142). Virological suppression rates were high throughout follow-up. At T1, suppression was achieved in 85.0% of INSTI, 50.0% of NNRTI, and 80.0% of PI/b recipients (p=0.308). A significant difference emerged at T2, favoring INSTI (94.3% vs 100.0% vs 73.3%; p=0.033), but this was not maintained at later timepoints (figure 2B).Conclusions In this real-world multicentre cohort of ART-naïve PWH with AHD, INSTI-based regimens were the predominant first-line strategy and demonstrated high durability over 5 years. Despite advanced immunosuppression at diagnosis, patients achieved robust immune recovery and high rates of virological suppression, broadly comparable across ART classes. However, a substantial proportion of participants were lost to follow-up, highlighting the need for strengthened linkage-to-care and retention strategies in this high-risk population.Abstract SC32 Table 1General characteristics (panel A) and viro-immunological parameters (panel B) of study populationAbstract SC32 Figure 1Plot showing transitions between ART classes from TO to T5 across al TimepointsAbstract SC32 Figure 2A) median CD4 evolution across timepoints by baseline cART regimen; B) virological suppression rates from year 1 to year 5 by initial cART class A", "authors": [ { "affiliations": [ "Infectious Diseases Unit, A.O.U. Policlinico Foggia, University of Foggia, Foggia, Italy" ], "name": "A Vergori" }, { "affiliations": [ "Laboratory of Biostatistics, Department of Medical, Oral and Biotechnological Sciences, University G. d’Annunzio Chieti-Pescara, Chieti, Italy" ], "name": "P Borrelli" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U. Policlinico Foggia, University of Foggia, Foggia, Italy" ], "name": "A Narducci" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U. Policlinico Foggia, University of Foggia, Foggia, Italy" ], "name": "IF Bottalico" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U. Policlinico Foggia, University of Foggia, Foggia, Italy" ], "name": "SM Ferrara" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U. Policlinico Foggia, University of Foggia, Foggia, Italy" ], "name": "C Grillo" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U. Policlinico Foggia, University of Foggia, Foggia, Italy" ], "name": "FRP Ieva" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U Consorziale Policlinico Bari, University of Bari, Bari, Italy" ], "name": "M Poliseno" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U Consorziale Policlinico Bari, University of Bari, Bari, Italy" ], "name": "A Saracino" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U Consorziale Policlinico Bari, University of Bari, Bari, Italy" ], "name": "A Cianciaruso" }, { "affiliations": [ "Infectious Diseases Unit, IRCCS San Martino, University of Genova, Genova, Italy" ], "name": "R Schiavoni" }, { "affiliations": [ "Infectious Diseases Unit, IRCCS San Martino, University of Genova, Genova, Italy" ], "name": "L Mezzogori" }, { "affiliations": [ "Infectious Diseases Unit, IRCCS San Martino, University of Genova, Genova, Italy" ], "name": "A Di Biagio" }, { "affiliations": [ "Infectious Diseases Unit, ASST Santi Paolo e Carlo, University of Milano Milano, Italy" ], "name": "A Santoro" }, { "affiliations": [ "Infectious Diseases Unit, ASST Santi Paolo e Carlo, University of Milano Milano, Italy" ], "name": "GC Marchetti" }, { "affiliations": [ "Infectious Diseases Unit, ASST Santi Paolo e Carlo, University of Milano Milano, Italy" ], "name": "C Tincati" }, { "affiliations": [ "Infectious Diseases Unit, A.O.U. Policlinico Foggia, University of Foggia, Foggia, Italy" ], "name": "S Lo Caputo" } ], "title": "SC32 Long-term treatment dynamics and immuno-virological recovery in advanced ART-naïve people with HIV", "uid": "f20fd1df-9a83-5e0e-bfcd-a0e2fac34e06" }