A randomized phase II clinical trial of personalized peptide vaccination with metronomic low-dose @entity786 in XXXX with metastatic castration-resistant @entity263 .

@entity1 @entity263 @entity786 @entity2286 @entity15082
UNASSIGNED: This study investigated the effect of metronomic @entity786 ( @entity15082 ) in combination with personalized peptide vaccination ( @entity2286 ) on regulatory T cells (Treg) and myeloid-derived suppressor cells (MDSC), and whether it could improve the antitumor effect of @entity2286 . Seventy @entity1 with metastatic castration-resistant @entity263 were randomly assigned (1:1) to receive @entity2286 plus oral low-dose @entity15082 (50  mg/day), or @entity2286 alone. @entity2286 treatment used a maximum of four peptides chosen from 31 pooled peptides according to human leukocyte antigen types and antigen-specific humoral immune responses before @entity2286 , for 8 subcutaneous weekly injections. Peptide-specific cytotoxic T lymphocyte (CTL) and immunoglobulin G responses were measured before and after @entity2286 . The incidence of grade 3 or 4 hematologic adverse events was higher in the @entity2286 plus @entity15082 arm than in the @entity2286 alone arm. Decrease in Treg and increase in MDSC were more pronounced in @entity2286 plus @entity15082 treatment than in @entity2286 alone (p  =  0.036 and p  =  0.048, respectively). There was no correlation between the changes in Treg or MDSC and CTL response. There was no difference in positive immune responses between the two arms, although overall survival in @entity1 with positive immune responses was longer than in those with negative immune responses (p  =  0.001). Significant differences in neither progression-free survival nor overall survival were observed between the two arms. Low-dose @entity15082 showed no change in the antitumor effect of @entity2286 , possibly due to the simultaneous decrease in Treg and increase in MDSC, in @entity1 under @entity2286 .
