To determine whether CYT107 administration increases the vaccine -induced antigen- specific T -cell immune response to PAP The effect on antigen -specific T -cell immune responses to PAP will be measured using the same assays and time points as for the primary endpoint, PA2024. 2. To assess the character of the T -cell immune response to PAP and PA2024 The effect on the number and percentage of PBMC subsets and T lymphocyte subsets (i.e., CD4+ and CD8+ T cell naïve, effector memory, and central memory subsets, CD4+ Treg and activated CD4+ and CD8+ T cells) will be assessed using multiparameter flow cytometric analysis of whole blood. The PBMC immunophenotyping assay will quantify Statistical Analysis Plan CITN12 -03 NCT 01881867 Version 2.0 13Nov2018 the absolute number and proportion of T cells (both CD8+ and CD4+), NK cells (CD56+CD3 -), NK T cells (CD56+CD3+), B cells (CD19+), monocytes (CD16+), dendritic cells (HLA -DR+ CD123+ or CD11c+), and CD122 (IL15R -beta) -expressing cells. An additional panel will quantify the absolute number and proportion of memory and naïve T cell subsets using ant ibodies to CD45RA, CCR7 and CD28 of regulatory T cells using antibodies to CD127 and CD25, and the activation state of T cells using antibodies to PD -1, ICOS, and HLA -DR, among others. The absolute change in each parameter as well as variance in change over time for each patient (mean, median, and SE/SD) will be evaluated.