Phase I trial of patient-oriented vaccination in HLA-A2-positive patients with metastatic hormone-refractory prostate cancer.
To evaluate the safety and toxicity of peptide vaccination for patients with metastatic hormone-refractory prostate cancer (HRPC) based on pre-existing peptide-specific cytotoxic T-lymphocyte (CTL) precursors in the circulation, 10 patients positive for human leukocyte antigen (HLA)-A2 with metastatic HRPC were enrolled in a phase I study. Peptide-specific CTL-precursors reactive to 16 kinds of vaccine candidates in the pre-vaccination peripheral blood mononuclear cells (PBMCs) were measured, and patients were followed by vaccination with only positive peptides (up to 4 kinds of peptides). Serum prostate-specific antigen (PSA) levels were monitored regularly. The peptide vaccination was safe and well tolerated with no major adverse effects. The most common toxicities were dermatologic reactions at the injection site. Increased CTL response to peptides was observed in 4 of 10 patients. Anti-peptide IgG was also detected in post-vaccination sera of 7 of 10 patients. One patient showed the disappearance of a pelvic bone metastasis after five vaccinations. Three patients showed a decrease of serum PSA level from the baseline after the vaccination, but no patients showed a serum PSA level decrease of >/= 50%. The median survival duration of study patients was 22 months with follow-up from 3 to 27 months. We consider that the increase in cellular and humoral immune responses, and decrease in PSA level in some patients justify further development of peptide vaccination for metastatic HRPC patients.
Noguchi
Masanori
M
Department of Urology, Kurume University School of Medicine, ururume 830-0011, Japan. noguchi@med.kurume-u.ac.jp
Itoh
Kyogo
K
Suekane
Shigetaka
S
Yao
Akihisa
A
Suetsugu
Norie
N
Katagiri
Kazuko
K
Yamada
Akira
A
Yamana
Hideaki
H
Noda
Shinshi
S
D000230:Adenocarcinoma / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D000368:Aged; D019496:Cancer Vaccines / Q000009:adverse effects / Q000627:therapeutic use*; D019008:Drug Resistance, Neoplasm; D007987:Gonadotropin-Releasing Hormone / Q000627:therapeutic use; D015789:HLA-A2 Antigen / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D022223:Vaccines, Subunit / Q000009:adverse effects / Q000276:immunology* / Q000627:therapeutic use
D019496:Cancer Vaccines; D015789:HLA-A2 Antigen; D007074:Immunoglobulin G; D022223:Vaccines, Subunit; D007987:Gonadotropin-Releasing Hormone; D017430:Prostate-Specific Antigen