Conventional vaccine design

Finally, besides conventional liposomes that are made from natural (e.g., egg yolk and soybean) or synthetic phospholipids, novel liposomes called archaeosomes that are prepared from the polar ether lipids extracted from various archaeobacteria proved also interesting for the design of vaccines as peptide antigen carriers (71) and as powerful self-adjuvanting vaccine delivery vesicles that promote both humoral and cell-mediated immunity (72). Related to this, one can mention that pseudopeptides, which are less prone to proteolysis when conjugated to liposomes, were also competent in triggering a humoral immune response (73). 

Plasma-derived hepatitis B virus vaccine is prepared from the plasma of chronic HBsAg carriers, and consists of purified, inactivated 20-nm HBsAg particles adsorbed on to an aluminium adjuvant. The use of a vaccine produced with plasma derived from infected individuals represented a major departure from conventional approaches, and safety testing has therefore been designed to cover all possibilities of risk and to ensure freedom from transmission of residual HBV and other blood-borne agents. Various clinical trials (SEDA-10, 289) (SEDA-11, 289) have confirmed the safety of plasma-derived hepatitis B virus vaccines produced by different manufacturers. Fears that plasma-derived vaccine may transmit AIDS can be considered unfounded. 

Cancer vaccine trials are often conducted in advanced patients resistant to conventional treatments such as chemo- or radiotherapy. Although early treatment with immune therapy is not likely to happen soon, well-designed combinations of established treatments with immune therapy would be an important step towards achieving the full potential of cancer vaccines. 

Two similarly designed studies have compared the reactogenicity and safety of novel quadrivalent vaccines compared to conventional bivalent vaccines [27,28 ]. Both studies found similar safety profiles in the 6- to 35-month and 3- to 17-year-old age groups. The most common AE in the first 7 days post vaccination was found to be injection-site pain. One study group found that injection-site pain was slightly higher (65.4% versus 54.6-55.7%) for the quadrivalent vaccine group [27,28 ]. 

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