Development of a cytomegalovirus vaccine: lessons from recent clinical trials

Abstract
Cytomegalovirus-caused diseases are preventable. We believe that both neutralising antibodies and cell-mediated immunity are necessary for prevention. Of the CMV proteins, gB and pp65 are the minimum requirements in a vaccine to induce neutralising antibodies and cytotoxic T-lymphocyte (CTL) responses. Immunisation with additional proteins, e.g., gH, gN for neutralising antibodies and IE1exon 4 and pp150 for CTL responses, would strengthen protective immune responses. Approaches to development of a safe and effective cytomegalovirus (CMV) vaccine for the prevention of CMV diseases include: a) a live attenuated vaccine (Towne strain); b) recombinant constructs of the attenuated Towne and the virulent Toledo CMV strains; c) subunit glycoprotein B (gB) adjuvanted with MF59 to induce neutralising antibodies; d) phosphoprotein 65 (pp65) peptide-based vaccines to induce (CTL) for use in therapeutic vaccination; e) canarypox-CMV recombinants, e.g., ALVAC-CMV(gB) and ALVAC-CMV (pp65) to induce neutralising antibo...