Methods
We conducted the current early phase II study of the PPV in children
diagnosed with refractory solid cancer. The details of the protocol are
given in Supplemental Appendix A1. The patient profiles are presented in
Table 1. Four patients with pediatric sarcoma (alveolar rhabdomyosarcoma
[ARMS], osteosarcoma, alveolar small cell tumor, and Wilms tumor,
respectively) were enrolled in this study between October 2016 and March
2017. The safety profile was assessed by monitoring the occurrence of
adverse events according to the National Cancer Institute Common
Terminology Criteria for Adverse Events (version 4.0). For measuring the
IgG responses to 31 peptides, IgG titers specific to the antigen
peptides in the plasma were evaluated by using a bead-based multiplex
Luminex assay, as previously described.5-12 We adopted
“Fluorescence Intensity Unit (FIU)” for measuring peptide-specific IgG
response associated with personalized vaccine. Komatsu reported the
comparison between the IgG measured by ELISA and
FIU12. The total sums of the immunoglobulins specific
to each peptide were calculated. The protocol was approved by the Kurume
University Ethical Committee and registered in the UMIN Clinical Trials
registry (UMIN # 000030249). The patient caregivers were given a full
explanation of the protocol and provided informed consent before
enrollment.