title: Long-term Vaccination with Multiple Peptides Derived from Cancer-Testis Antigens Can Maintain a Specific T-cell Response and Achieve Disease Stability in Advanced Biliary Tract Cancer.
abstract: OBJECTIVE
  The prognosis of patients with advanced biliary tract cancer (BTC) is extremely poor and there are only a few standard treatments. We conducted a phase I trial to investigate the safety, immune response, and antitumor effect of vaccination with four peptides derived from cancer-testis antigens, with a focus on their fluctuations during long-term vaccination until the disease had progressed.
  
  
  METHODS
  Nine patients with advanced BTC who had unresectable tumors and were refractory to standard chemotherapy were enrolled. HLA-A*2402-restricted epitope peptides, lymphocyte antigen 6 complex locus K, TTK protein kinase, insulin-like growth factor-II mRNA-binding protein 3, and DEP domain containing 1 were vaccinated subcutaneously once a week at doses of 0.5, 1, or 2 mg and continued until disease progression. The adverse events were assessed by Common Terminology Criteria for Adverse Events and the immune response was monitored by an enzyme-linked immunospot assay or by flow cytometry. The clinical effects observed were tumor response, progression-free survival (PFS), and overall survival (OS).
  
  
  RESULTS
  Four-peptide vaccination was well tolerated. No grade 3 or 4 adverse events were observed. Peptide-specific T-cell immune responses were observed in seven of nine patients and clinical responses were observed in six of nine patients. The median PFS and OS were 156 and 380 days. The injection site reaction and CTL induction seemed to be prognostic factors of both PFS and OS.
  
  
  CONCLUSIONS
  Four-peptide vaccination was well tolerated and seemed to provide some clinical benefit to some patients. These immunologic and clinical responses were maintained over the long term through continuous vaccinations.
authors.affiliation: Department of Gastroenterological Surgery; Institute of Advanced Biomedical Engineering and Science, Tokyo, Japan. aruga@abmes.twmu.ac.jp
authors.forename: Atsushi
authors.initials: A
authors.lastname: Aruga
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Takeshita
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Kotera
authors.forename: Ryuji
authors.initials: R
authors.lastname: Okuyama
authors.forename: Norimasa
authors.initials: N
authors.lastname: Matsushita
authors.forename: Takehiro
authors.initials: T
authors.lastname: Ohta
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Takeda
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yamamoto
mesh_terms: D000368:Aged; D000951:Antigens, Neoplasm / Q000276:immunology; D001661:Biliary Tract Neoplasms / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D019496:Cancer Vaccines / Q000009:adverse effects / Q000276:immunology* / Q000627:therapeutic use; D018572:Disease-Free Survival; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D059871:HLA-A24 Antigen / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology / Q000378:metabolism; D008231:Lymphopenia / Q000139:chemically induced; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000378:metabolism; D013737:Testis / Q000276:immunology; D013997:Time Factors; D016896:Treatment Outcome; D014611:Vaccination / Q000379:methods*; D022223:Vaccines, Subunit / Q000009:adverse effects / Q000276:immunology* / Q000627:therapeutic use
chemical_list: D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D000939:Epitopes; C438506:HLA-A*24:02 antigen; D059871:HLA-A24 Antigen; D022223:Vaccines, Subunit; D007371:Interferon-gamma