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ImmunityBio announced preclinical results for its human Ad5 vaccine candidate that contains both the spike, or S, and nucleocapsid, or N, SARS-CoV-2 proteins for preventing COVID-19. The results were published in bioRxiv. First generation adenoviral-based vaccines are hampered by pre-existing adenovirus immunity, which reduces the immunogenicity of the vaccines. In addition, with vaccines that target S alone, there is a risk that they may be rendered ineffective due to the high likelihood of spike protein mutation. The preclinical study showed that the bivalent hAd5 vaccine resulted in T cell and humoral immune responses against SARS-CoV-2 S and N antigens. Immunogenicity in mice was assessed after two doses given 21 days apart. Immune responses measured on Day 28 showed that the vaccinations elicited robust T cell responses to SARS-CoV-2. Importantly, a statistically significant CD4+ T cell response to N protein was generated in all five mice. This is consistent with studies in patients who have recovered from SARS-CoV who show memory T cells to N protein. Four out of five mice generated an S-specific antibody response, with evidence of Th1 dominance. Two of these mice demonstrated potent neutralizing antibodies as they relate to the RBD ACE2 interface. Analysis of both T cell cytokine responses and antibody isotypes demonstrated that the overall immune response was skewed towards T helper, or Th1, cell dominance important for mitigating the risk of antibody-dependent enhancement, or ADE, of infection. ImmunityBio plans to administer the hAd5 vaccine both as a prime and a booster to sustain protection against SARS-CoV-2. The company has completed GMP dosage formulations that have already been manufactured in the United States. In ongoing studies, use of this vaccine construct in oral and sublingual formulations to induce mucosal, cell-mediated and humoral immunity are being explored. In May, NantKwest and ImmunityBio entered into a binding term sheet to pursue collaborative joint development, manufacturing, and marketing of certain COVID-19 therapeutics and vaccines. The parties intend to equally share all costs relating to developing, manufacturing and marketing the product candidates globally; the net profits from the collaboration products will be shared, with 60% in favor of the party contributing the product on which the sales are based. The companies are negotiating the terms of a definitive agreement and anticipate finalizing documentation before August 21 after which either party can terminate the binding term sheet upon five business days' written notice if an agreement is not finalized.