Results
Study flowchart (Supplementary figure 1 ) shows the selection process of PWH starting from the original Polimmune cohort. Overall, 48 individuals were included in our analysis. Most of them were male (39/48, 81.2%), with a mean age of 46.3 years and all were on ART, with integrase strand transfer inhibitors (34/48, 77.3%) and nucleoside reverse transcriptase inhibitors (42/48, 87.5%) representing the drugs most frequently administered. The mean CD4+ T cell count was 798 cells/µL with a mean percentage of 35.3% and a median ratio of 0.98. Overall, 19/48 (39.6%) patients had achieved the OIR and 11/48 (22.9%) had received an AIDS diagnosis. The mean VL at vaccination was <20 copies/mL in all but 9 patients who had, respectively, 85, 50, 47, 33, 31, 29, 28, 22 and 20 copies per mL, and were considered as VB occurring before vaccination. Table 1 and Table 2 show population characteristics at enrolment and VL and immunologic profile at follow-up visits, respectively. Overall, no difference was recorded between VB incidence before and after vaccination [11/48 (23%) vs 15/48 (31.3%), p=0.42]. Figure 1 depicts the trend of viral load in all the enrolled patients, before and after vaccination.Table 3 reports the association between selected variables and VB occurrence after vaccination, with no significant findings.
As post hoc analysis we included also 8 PWH previously excluded for not reaching the definition of viral suppression before vaccination. In this extended cohort, we observed 15 HIV RNA increase out of 56 PWH (26.8%) before vaccination and 23 HIV RNA increase out of 56 PWH after vaccination (41.1%). This difference in incidence among the two groups remained not significant (p=0.10) but a strong association between HIV RNA increase occurrence before and after vaccination [p=0.02, OR 4.3 (95% CI 1-22-15.17)] was found. Among the 8 PWH excluded, 4 (50%) had a HIV RNA increase before vaccination but all (100%) experienced a HIV RNA increase after vaccination.