A candidate vaccine based on the hepatitis C E1 protein: tolerability and immunogenicity in healthy volunteers.

The tolerability and immunogenicity of the hepatitis C virus E1 protein as a candidate vaccine was examined in a Phase I, single-arm study. Twenty healthy male volunteers were injected in the deltoid muscle at weeks 0, 3 and 6 with 20 microg recombinant E1 adsorbed on alum. A fourth (booster) dose was administered to 19 subjects at week 26.

A pilot study of therapeutic vaccination with envelope protein E1 in 35 patients with chronic hepatitis C.

New treatments are needed for chronic hepatitis C patients in whom viral clearance cannot be achieved. Thirty-five chronic hepatitis C patients (genotype 1) were randomized to receive 20 mug of recombinant HCV E1 (E1) (n = 26) or placebo (n = 9) intramuscularly at weeks 0, 4, 8, 12, and 24. Thirty-four then received open-label E1 vaccine at weeks 50, 53, 56, 59, 62, and 65.