INOVIO’s COVID-19 Vaccine Candidate, INO-4800, Provides Broad Cross-reactive Immune Responses In Humans Against Variants of Concern
INOVIO a biotechnology company focused on rapidly bringing to market precisely designed DNA medicines to treat and protect people from infectious diseases, and cancer, announced the results of a study focusing on the human immune responses induced by INOVIO’s DNA vaccine candidate for COVID-19, INO-4800, against variants of concern. The results showed that INO-4800 induced a robust T cell response against all spike protein variants tested, which the company believes will be key in providing protection against SARS-CoV-2 variants, in addition to providing similar levels of neutralizing activity against both the UK and Brazilian variants as those against the original strain.
Dr. J. Joseph Kim, INOVIO’s President & CEO, said, “These results are consistent with our expectation that INO-4800, which was found to be well-tolerated and able to produce a balanced immune response in our Phase 1 trial, is able to generate both neutralizing antibodies and robust T cell responses – both of which will be essential to protect against the emerging variants of concern.”
Regarding INO-4800 development Dr. Kim said, “We will report Phase 2 results in 2Q, and, with FDA concurrence, expect to move into Phase 3 in the second quarter of this year. Our COVID vaccine’s projected safety profile, its stability at room temperature for more than a year, and likely ability to safely boost numerous times positions INOVIO’s COVID-19 vaccine as an important factor in addressing the virus in its pandemic and endemic states.”
In the study, clinical samples were collected at varying timepoints post-immunization from subjects in INOVIO’s Phase 1 US-based INO-4800 clinical trial. Antibodies capable of neutralizing activity were measured against the spike protein variants tested, including B.1.1.7 (UK variant), B.1.351 (South African variant) and P.1. (Brazilian variant). The study showed the T cell responses induced by INO-4800 vaccination were fully maintained against the UK, South African and Brazilian variants when compared to the T cell responses to the original Wuhan strain. The neutralization levels of INO-4800 against South Africa and UK variants were reduced to the levels similar to the previous reports of mRNA or viral vector vaccines. Furthermore, despite recent reports showing a reduction in neutralizing activity against the Brazilian variant by the mRNA or viral vector vaccines, INO-4800 generated robust neutralizing antibodies at levels against Brazilian variant which were comparable to those against the Wuhan strain. Taken together with the data showing the maintenance of T cell activity, the results reported in this study provide a comprehensive overview of cross-reactive cellular and humoral immune responses against SARS-CoV-2 variants for INO-4800 vaccinated individuals that may be important for protection against variant strains of SARS-CoV-2.
Collectively, the studies showcase how the combination of robust T cell responses in conjunction with neutralizing antibody responses provide an important defense against both emerging and potential future viral variants, exhibiting broad protection against the virus and less impacted by the mutational changes a virus may undergo.