Bioport gets into the new adjuvant act

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Vaccine. 2006 Aug 17;

Increased potency of BioThrax(®) anthrax vaccine with the

addition of the C-class CpG oligonucleotide adjuvant CPG 10109.

Gu M, Hine PM, W, Giri L, Nabors GS.

Emergent BioSolutions, 300 Professional Drive, Gaithersburg, MD

20879, USA.

The inclusion of an adjuvant, in addition to the existing

aluminum hydroxide, in the formulation of the licensed anthrax

vaccine BioThrax(®) may have the potential to positively modify

immune responses. Some potential desirable outcomes from the

inclusion of an additional adjuvant include increased immune response

kinetics, increased response rates, more prolonged antibody decay

rates, and the ability to use less antigen per dose or fewer doses to

achieve immunity. One promising group of adjuvants that is being

investigated with a variety of vaccines and which has been shown to

cause many of these effects are oligonucleotides which contain

unmethylated CpG motifs. The C-class oligonucleotide CPG 10109,

constructed of a mixed phosphorothioate/phosphodiester backbone and

containing 3 CpG motifs, was added to various dilutions of BioThrax

and used in mouse and guinea pig immunogenicity studies. Anti-

protective antigen (PA) IgG ELISAs and the anthrax toxin

neutralization assay (TNA) were performed on serum samples from both

species. Anti-PA IgG and TNA responses were approximately 10-fold

higher after a single dose of undiluted or diluted BioThrax upon

addition of 100mug CPG 10109 in the mouse regardless of the route of

immunization. Responses were also significantly greater in the guinea

pig after receiving CpG-adjuvanted undiluted BioThrax or CpG-

adjuvanted BioThrax diluted 1:5, 1:10 or 1:30 compared to those

achieved with BioThrax alone. A guinea pig spore challenge study

showed that a single injection of BioThrax vaccine diluted 1:10 in

the presence of 25mug CPG 10109 was as protective as undiluted

BioThrax, whereas a single injection of BioThrax diluted 1:10 was not

protective. Taken together with the results from the immunogenicity

studies, these results suggest that a CpG adjuvant could be used to

reduce the dose of active ingredient required to elicit a protective

response, and could lead to improved immune response kinetics.

Meryl Nass, MD

Mount Desert Island Hospital

Bar Harbor, Maine 04609

207 288-5081 ext. 220