Statistical analysis
The immunology analysis was performed using either Prism 9.3 or higher (GraphPad Software, San Diego, CA), SAS 9.4 (SAS Institute, Cary, NC), or R 4.03 (The R Foundation, Vienna, Austria). Categorical data were analyzed using Fisher’s exact test and a 0.05 level of significance (α = 0.05) with Bonferroni adjustments whenever pairwise comparisons were made between more than two categories.Continuous data were compared between two treatment groups using the Wilcoxon rank-sum test since the normality assumption was not met for any dataset according to the Shapiro–Wilk test. Response rates were compared using Fisher’s exact test. Differences were detected based on a two-sided test and IgG antibody responses (total IgG, IgG1, IgG2, IgG3, and IgG4) to the ID93 antigen were measured by ELISA using serum collected from a given participant. At each time point, the MEPT calculated from duplicates was reported. At each post-injection time point, the following Post:Pre Ratio was calculated:A participant was considered an antibody positive responder at a given time point if system suitability criteria for a given ELISA were met and the Post:Pre Ratio at that time point was ≥4.Cellular responses to the ID93 protein were evaluated by measuring cytokine production in PBMCs by ELISpot assay and by ICS with flow cytometry. IFN-γ and IL-10 ELISpot assays were performed on samples from Study Days 0, 14, 56, 70, 84, and 224 to determine the proportion of PBMCs producing IFN-γ or IL-10 in response to stimulation with ID93 or unstimulated (PBS). For analysis, background-subtracted spot-forming units (SFU) values were calculated. At each post-injection time point, the change from baseline was calculated by subtracting the background-subtracted SFU value at baseline from a given time point. Both background-subtracted SFU and change from baseline SFU were summarized for each participant and visit day. The responder status at each time point was determined using the MIMOSA model, a Bayesian statistical framework that controls the false-discovery rate to 0.1%PBMC ICS was performed on samples from Study Days 0, 7, 14, 56, 63, 70, 84, and 224 to determine the proportion of single and multi-functional CD4 and CD8 T cells producing various combinations of IFNγ, TNF, IL-2, IL-4, IL-21, and CD154 in response to ID93 stimulation. A gate was applied for each functional marker, not accounting for the co-expression of other markers (Supplementary Figs. At each post-injection time point, the change from baseline was calculated by subtracting the background-subtracted frequency (%) at baseline from a given time point. Both background-subtracted and change from baseline frequencies were summarized for each participant and visit day. Response status was determined for each participant, visit day, and T cell subset using the MIMOSA model. The responder rate was then calculated based on the total number of participants analyzed within each treatment group.