ARTES and Burnet Institute publish data on production and immunogenicity of malaria transmission-blocking vaccine candidates

ARTES Biotechnology and Burnet Institute recently published data on the efficient production of malaria vaccine candidates using virus-like particles (VLP) presenting malaria transmission-stage antigens, which were capable of inducing transmission-blocking antibodies. The development project funded a.o. by the PATH Malaria Vaccine Initiative started in 2014 aimed at strategies to produce vaccines that block the transmission of malaria from mosquitoes to humans, which has been identified as an important global goal.

Purified transmission-stage vaccine antigens (Pfs25 and Pfs230) were produced as chimeric VLPs with ARTES’ METAVAX® platform. The study results demonstrated that the VLPs effectively induced functional transmission-reducing antibodies, assessed with the widely used standard membrane feeding assays for evaluation of malaria vaccines.

Malaria is one of the major threats to human health globally, and the elimination of malaria depends on the development of an effective vaccine. Currently, the most advanced malaria vaccine has been found to be moderately efficacious. Thus, it is crucial to develop new strategies for improved vaccine formulations that can generate potent immunity to malaria. Chimeric VLPs displaying target antigens have emerged as a promising strategy to develop and accelerate new malaria vaccine candidates.

ARTES Biotechnology, the German biopharmaceutical contract research and development company specializes in microbial cell line and process development for recombinant proteins and vaccines together with colleagues at Burnet Institute, Australia, have recently published data on the use of chimeric VLPs (METAVAX® technology platform).Two original articles are available in the international open-access journal, PLOS ONE.

Under the titleDisplay of malaria transmission-blocking antigens on chimeric duck hepatitis B virus-derived virus-like particles produced in Hansenula polymorpha” the development of the Hansenula yeast cell lines and processes for the expression of transmission-blocking malaria vaccine candidates, Pfs25 and Pfs230, as VLPs are described. The accompanying article entitled “Malaria vaccine candidates displayed on novel virus-like particles are immunogenic and induce transmission-blocking activity” further present data supporting the successful induction of an immune response against the VLPs using animal studies.

The results demonstrated that the incorporation of leading transmission-stage antigens into the METAVAX® platform is a promising and novel strategy for their display on nano-scaled particles. The VLP platform is suitable for the development of multi-component vaccines to elicit functional transmission-blocking immunity. Furthermore, competitive processes for efficient production and purification are now available and can be transferred to other promising VLP vaccine targets. Future work to evaluate immune responses in larger studies of animal models using different immunization regimens and to optimize antigen presentation by VLPs will be highly beneficial to accelerate the use of this platform for malaria vaccine development.

“With the production of new malaria vaccine candidates, another milestone in the application of our yeast based VLP platform METAVAX® for the development of human and veterinary vaccines is showcased, Managing Director of ARTES, Dr Michael Piontek said.

The generation of antibodies that block malaria transmission in animal studies, is a promising step forward and highlights the potential use of this approach for malaria vaccine development, said Prof James Beeson, Head of the Malaria Immunity and Vaccines group at Burnet Institute.