On Jul. 23, 2020, Dynavax Technologies and Medigen Vaccine Biologics announced their collaboration to develop an adjuvanted vaccine candidate to protect against COVID-19. The collaboration is evaluating the combination of MVC’s stable prefusion form of the SARS-CoV2 recombinant spike protein with Dynavax’s advanced adjuvant CpG 1018, the adjuvant contained in Dynavax’s FDA-approved adult hepatitis B vaccine.

MVC’s subunit vaccine is based on the stable prefusion form of the SARS-CoV2 recombinant spike protein with global technology license from the U.S Vaccine Research Center at National Institutes of Health (NIH). Preclinical studies demonstrated that the vaccine candidate adjuvanted with CpG 1018 generated strong immune responses in experimental animals.

An adjuvant is a pharmacological or immunological agent that modifies the effect of other agents. Adjuvants are added to a vaccine to boost the immune response to produce more antibodies and longer-lasting immunity, thus minimizing the dose of antigen needed. Adjuvants may also be used to enhance the efficacy of a vaccine by helping to modify the immune response by particular types of immune system cells.

CpG 1018 is the adjuvant used in HEPLISAV-B® [Hepatitis B Vaccine (Recombinant), Adjuvanted], an adult hepatitis B vaccine approved by the U.S. Food and Drug Administration (FDA). Dynavax developed CpG 1018 to provide an increased vaccine immune response, which has been demonstrated in HEPLISAV-B. In pre-clinical and clinical studies, results demonstrated that the addition of CpG 1018 increases antibody concentrations, stimulates helper (CD4+) and cytotoxic (CD8+) T cell populations and generates robust T and B cell memory responses.

Additionally, CpG 1018 strongly favors development of the Th1 subset of helper T cells, the type of helper T cell that is essential for protection from infections with viruses and intracellular bacteria. CpG 1018 targets a single, well defined receptor (TLR9) expressed on only a few key cell types and the mechanisms of action as an adjuvant are quite well understood. CpG 1018 provides a well- developed technology and a significant safety database, potentially accelerating the development and large-scale manufacturing of a COVID-19 vaccine. Upon completion of on-going scale up activities, the existing equipment capacity for CpG 1018 will be 600 million to 1.2 billion adjuvant doses annually, depending on final dose selected.