Immunogenicity and safety of a novel therapeutic hepatitis C virus (HCV) peptide vaccine: a randomized, placebo controlled trial for dose optimization in 128 healthy subjects.
As interferon/ribavirin-based standard therapy is curative in only about half of HCV patients, there remains an important need for alternatives including vaccines. The novel peptide vaccine IC41 consists of five synthetic peptides harboring HCV T cell epitopes and poly-L-arginine as synthetic adjuvant. In this randomized, placebo-controlled trial, 128 HLA-A2 positive healthy volunteers received four s.c. vaccinations of seven different doses IC41, HCV peptides alone, poly-l-arginine alone or saline solution, every 4 weeks. IC41 was safe and well tolerated. Mild to moderate local reactions were transient. Immunogenicity was assessed using T cell epitope specific [3H]-thymidine proliferation, IFN-gamma ELIspot and HLA-tetramer assays. IC41 induced responses in all dose groups. Higher responder rates were recorded in higher dose groups and increasing number of vaccinations were associated with higher responder rates and more robust responses. Poly-L-arginine was required for the aimed-for Th1/Tc1-type immunity (IFN-gamma secreting T cells).
Department of Clinical Pharmacology, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria.
Christa
C
Firbas
Bernd
B
Jilma
Erich
E
Tauber
Vera
V
Buerger
Sandra
S
Jelovcan
Karen
K
Lingnau
Michael
M
Buschle
Jürgen
J
Frisch
Christoph S
CS
Klade
D000293:Adolescent; D000328:Adult; D006526:Hepatitis C / Q000517:prevention & control*; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D008875:Middle Aged; D010919:Placebos; D012016:Reference Values; D016037:Single-Blind Method; D013601:T-Lymphocytes / Q000378:metabolism / Q000473:pathology; D014765:Viral Vaccines / Q000009:adverse effects* / Q000276:immunology*
D010919:Placebos; D014765:Viral Vaccines; D007371:Interferon-gamma