Panblok-H1+advax H1N1/2009pdm vaccine: Insights into rapid development of a delta inulin adjuvanted recombinant pandemic influenza vaccine

An Advax-CpG adjuvanted recombinant H5 hemagglutinin vaccine protects mice against lethal influenza infection

There is a major unmet need for strategies to improve the immunogenicity of vaccines to protect against highly pathogenic avian influenza strains with pandemic potential. This study tested the ability of adjuvants based on delta inulin (Advax™) alone or combined with a TLR9 agonist (Advax-CpG™) to enhance the immunogenicity of recombinant H5 hemagglutinin antigen expressed in insect cells (rH5HA) to protect mice against lethal influenza infection. The Advax-adjuvanted rH5HA induced high serum hemagglutination inhibition activity, as well as Th1 and Th2 cytokine secreting CD4 and CD8 T cells. Immunization protected mice against a lethal heterosubtypic H5N1 virus challenge. Mice immunized with an Advax-adjuvanted rHA2 stem antigen prepared by enzymatic cleavage of rH5HA produced serum antibodies devoid of hemagglutination inhibition activity, but these anti-HA2 antibodies were nevertheless able to transfer protection against lethal H1N1 or H3N2 infections to naïve mice. We hypothesize that the enhanced protection afforded by Advax-adjuvanted rH5HA may be mediated by the combination of neutralizing antibodies directed at the HA head, anti-HA2 stem antibodies plus memory CD4 + and CD8 + T cells. This outcome supports further development of the Advax-adjuvanted rH5 pandemic influenza vaccine platform.

Evaluation of the safety and efficacy of AdvaxTM as an adjuvant: A systematic review and meta-analysis

PURPOSE

Developing a vaccine with improved immunogenicity is still a growing priority for many diseases. Different types of adjuvants may be beneficial to initiate and maintain the long-lasting immunogenicity of vaccines. Evidence has shown that polysaccharide adjuvants are efficient in improving immunological mechanisms with their biocompatibility and biodegradability characteristics. In this study, we aimed to investigate the safety and efficacy of Advax^TM an adjuvant derived from delta inulin.

METHODS

A systematic research was performed in Pubmed, Web of Science, and Scopus databases for the following keywords; "Advax^TM" OR "delta inulin" until December 14th, 2020. RevMan 5.4.1 software was used for cumulative meta-analysis and bias analysis. We also used GraphPad Prism 6 software for the figures.

RESULTS

In the cumulative meta-analysis, it was found that seroconversion and geometric mean titers (GMT) levels significantly increased in Advax^TM-adjuvanted group (mean difference: 12.31, 95% Cl [4.14, 20.47], p ​= ​0.003; 17.10, 95% Cl [4.35, 29.85], p ​= ​0.009, respectively). We also observed that Advax^TM could be effective in improving immunogenicity by inducing T-cell responses and plasmablast generation in viral vaccines.

CONCLUSIONS

In this study, it was shown that Advax^TM is a safe and well-tolerated adjuvant. Advax^TM could be a potent adjuvant in increasing the protection and immunogenicity of different vaccines without safety issues. However, further studies are needed to verify these effects of Advax^TM adjuvant.

Recombinant protein vaccines, a proven approach against coronavirus pandemics

With the COVID-19 pandemic now ongoing for close to a year, people all over the world are still waiting for a vaccine to become available. The initial focus of accelerated global research and development efforts to bring a vaccine to market as soon as possible was on novel platform technologies that promised speed but had limited history in the clinic. In contrast, recombinant protein vaccines, with numerous examples in the clinic for many years, missed out on the early wave of investments from government and industry. Emerging data are now surfacing suggesting that recombinant protein vaccines indeed might offer an advantage or complement to the nucleic acid or viral vector vaccines that will likely reach the clinic faster. Here, we summarize the current public information on the nature and on the development status of recombinant subunit antigens and adjuvants targeting SARS-CoV-2 infections.

Randomized controlled trial demonstrating the benefits of delta inulin adjuvanted immunotherapy in patients with bee venom allergy

Background

Allergic reactions to Hymenoptera insect stings remain a major global clinical problem. Although effective, parenteral desensitization regimens require use of costly venom extracts and require frequent visits over extended periods of time.

Objective

Adjuvants are commonly used to enhance the efficacy of infectious disease vaccines, and this study asked whether Advax (Vaxine Pty Ltd, Adelaide, Australia), a novel noninflammatory polysaccharide adjuvant, might provide similar benefits for allergy desensitization.

Methods

A randomized, controlled phase 1/2 trial was undertaken in 27 adults with a history of rapid-onset systemic allergic reactions to honeybee stings and positive specific IgE levels to evaluate the safety and efficacy of honeybee venom immunotherapy (HBVIT) combined with Advax adjuvant. Venom immunotherapy (VIT) was administered monthly for 30 months after achievement of maintenance doses.

Results

Advax-adjuvanted HBVIT was well tolerated. Around week 14 of VIT, specific IgG₄ responses peaked in both groups but increased earlier, peaked higher, and were better maintained through the end of the study in the Advax-adjuvanted arm. Several different patterns of serologic response to VIT were seen; some subjects had a dominant IgG₄ response, some had a combined IgG₄ and IgG₁ response, and some had an exclusively IgG₁ response. In some subjects specific IgE levels increased during the induction phase and then decreased, whereas in others specific IgE levels progressively decreased from the start of VIT.

Conclusion

Advax adjuvant favorably enhanced the immunogenicity of HBVIT, with an early and prolonged switch to specific IgG₄ production. The ability of Advax adjuvant to enhance VIT efficacy warrants further study.

Adjuvant strategies to improve vaccination of the elderly population

Immunosenescence contributes to increased incidence and severity of many infections in old age and is responsible for impaired immunogenicity and efficacy of vaccines. Adjuvants are one strategy to enhance immunogenicity of vaccines. The oil-in-water emulsions MF59TM and AS03, as well as a virosomal vaccine have been licensed in seasonal or pandemic influenza vaccines and are/were used successfully in the elderly. AS01, a liposome-based adjuvant comprising two immunostimulants has recently been approved in a recombinant protein vaccine for older adults, which showed very high efficacy against herpes zoster in clinical trials. Several adjuvants for use in the older population are in clinical and preclinical development and will hopefully improve vaccines for this age group in the future.