The final Phase II data, along with the safety database from prior clinical trials, will be used by ID Biomedical to approach Health
A compilation of all of the human clinical trial data of StreptAvax vaccine shows that the unique, multivalent vaccine formulation induces high titers of M protein-specific antibodies against all of the component subunit proteins in the product. The current serologic data, unblinded by a third party uninvolved in the safety analysis, indicate that all 27 streptococcal antigens in the vaccine demonstrate a statistically-significant (p less than or equal to 0.05 by Mann-Whitney test) increase in post-immunization antibodies, detected by serotype-specific ELISA assay, in StreptAvax recipients when contrasted with recipients of the comparator vaccine. StreptAvax recipients responded to a median of 24 of 27 streptococcal antigens (89 percent) administered in the vaccine; indistinguishable from the result reported for the Phase I trial. The opsonic, or bactericidal, activity for the last cohort of the Phase II study has not be examined to date, but the vaccine-induced antibody increases detected by ELISA in this cohort are consistent with previous studies of StreptAvax that correlated vaccine-induced antibodies with bactericidal or killing activity of the vaccine. Thus far, the bactericidal activity of vaccine-induced antibodies against each serotype in StreptAvax appears similar to, or greater than, an M-protein based group A streptococcal vaccine that was tested in the 1970s and shown to protect humans against subsequent challenge with live group A streptococcus.
"This is extremely important data," stated Anthony Holler, M.D., CEO of ID Biomedical. "The critical roadblock to group A streptococcal vaccine development has been to design a vaccine that is not only safe, but also deals with the complexity of the epidemiology of this disease. The exciting potential of the StreptAvax vaccine is that we have shown in the clinic that we have a potentially safe vaccine, as well as a multivalent recombinant protein vaccine that can deliver a broad immune response to all of the serotypes covered in the vaccine. The fact that this immune response has been shown to correlate with bactericidal killing, and that bactericidal killing has been shown to be associated with protection, gives us great confidence to go forward."
The StreptAvax vaccine is composed of 26 M protein fragments that were genetically engineered into complex 'fusion proteins' that allow the vaccine to target 26 serotypes of group A streptococci with a simple mixture of four proteins. The vaccine types were selected from epidemiologically important serotypes of group A streptococci. Recent
ID Biomedical also announced that it and Dr. James Dale of the
Source: ID Biomedical