On July 13, 2020, the Company announced positive results from the preclinical studies of its intranasal
COVID-19 vaccine candidate, AdCOVID. The studies, which were conducted in collaboration with the University of Alabama at Birmingham, or UAB, showed strong serum neutralizing activity and potent mucosal
immunity in the respiratory tract. The induction of IgA antibody in the respiratory tract may be necessary to block both infection and transmission of the virus to prevent further spread of COVID-19. Based on
these findings the Company plans to begin manufacturing of AdCOVID and advance the vaccine candidate to a Phase 1 safety and immunogenicity study in the fourth quarter of 2020.
AdCOVID is designed to express the receptor binding domain, or RBD, of the
SARS-CoV-2 virus spike protein, a key immune target that is essential for the virus to bind to cells and initiate infection. By focusing the immune response to this
portion of the viral spike protein, AdCOVID elicited a strong systemic antibody response against RBD in mice, achieving serum IgG antibody concentrations greater than 800 micrograms per milliliter just 14 days after administration of a single
intranasal dose. In addition, AdCOVID stimulated serum viral neutralization titers of 1:320 by Day 28, which was two times higher than the titer recommended by the U.S. Food and Drug Administration for investigational convalescent plasma as a
treatment for severe COVID-19. In a separate study conducted by UAB, a single intranasal dose of AdCOVID stimulated a 29-fold induction of mucosal IgA in bronchoalveolar
fluid of vaccinated mice. This level of IgA antibody stimulation is well above that associated with protection from disease in clinical studies of other mucosal vaccines.
In the preclinical studies, vaccination with AdCOVID caused the rapid recruitment of immune cells into the respiratory tract and draining
lymph nodes consistent with induction of mucosal and systemic immunity. Increases in CD8+ and CD4+ T cells, dendritic cells and NK cells were observed in the respiratory tract, and germinal center and memory B cells as well as T follicular helper
cells were observed in regional lymph nodes and the spleen. Importantly, the latter cell types have been associated in prior vaccine development research with long-lived antibody responses. Preclinical data for antigen-specific T cell response are
expected in the coming weeks.
Intranasal dosing provides AdCOVID with the potential to be administered rapidly and without the need for
needles, syringes or trained healthcare personnel. In addition, AdCOVIDs expected room temperature stability profile may allow for broad distribution of the vaccine without the need for expensive cold-chain logistics, such as refrigeration or
freezing.
Forward-Looking Statement
The Company cautions you that statements included in this Current Report on Form 8-K that are not a
description of historical facts are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including without limitation, the timing of key milestones for our clinical assets, the timing and
approval of the AdCOVID investigational new drug application, or IND, submission to the U.S. Food and Drug Administration, or FDA, expected to be submitted later this year, the initiation and timing of the AdCOVID Phase 1 clinical trial in Q4 2020,
the potential immunization effects of AdCOVID, our ability to manufacture AdCOVID beginning this year, and the prospects for regulatory approval, commercializing or selling any of our products or drug candidates. In some cases, forward-looking
statements can be identified by terminology such as may, could, should, anticipate, believe, estimate, expect, intend, plan,
predict and similar expressions and their variants or the negative of these terms or other comparable terminology, although not all forward-looking statements contain these words. The Company cautions that these forward-looking
statements are subject to numerous assumptions, risks, and uncertainties, which change over time. Important factors that may cause actual results to differ materially from the results discussed in the forward looking statements or historical
experience