The Novavax NVX-CoV2373 vaccine candidate is shown to be well-tolerated and elicited antibody response.
Novavax announced yesterday its NVX-CoV2373, coronavirus 2019 (COVID-19) vaccine candidate, was well-tolerated and elicited robust antibody responses numerically superior to that seen in human convalescent sera.
This comes from phase 1 data from its phase 1/2 randomized, observer-blinded, placebo-controlled trial. The investigational vaccine was delivered using its saponin-based Matrix-M adjuvant, which has demonstrated a potent and well-tolerated effect by stimulating the entry of antigen-presenting cells into the injection site and enhancing antigen presentation in local lymph nodes, boosting immune response.
“The phase 1 data demonstrate that NVX-CoV2373 with our Matrix-M adjuvant is a well‑tolerated COVID-19 vaccine with a robust immunogenicity profile,” Gregory Glenn, MD, president, Research and Development at Novavax. “Using a stringent wild-type virus assay performed by investigators at the University of Maryland School of Medicine, NVX‑CoV2373 elicited neutralizing antibody titers greater than those observed in a pool of COVID‑19 patients with clinically significant disease.”
The vaccine was evaluated using 2 doses at 2 dose levels (5 and 25 µg) in 131 healthy adults ages 18-59 years.
NVX-CoV2373 induced neutralization titers in 100% of participants; 5 µg adjuvanted dose group peak GMT: 3906 (95% CI, 2556 - 5970). All subjects developed anti-spike IgG antibodies after a single dose of vaccine, many of them also developing wild-type virus neutralizing antibody responses, and after dose 2, 100% of participants developed wild-type virus neutralizing antibody responses.
Both anti-spike IgG and viral neutralization responses compared favorably to responses from patients with clinically significant COVID‑19 disease. Importantly, the IgG antibody response was highly correlated with neutralization titers, demonstrating that a significant proportion of antibodies were functional.
Adverse events were generally mild. Following dose 1 of the vaccine, tenderness and pain were the most frequent local symptoms and systemic events were individually less frequent with headache, fatigue, and myalgia being reported most commonly. As expected, following dose 2, greater reactogenicity was reported, although the majority of symptoms were reported as ≤ Grade 1. The average duration of events was <2 days.
In preclinical trials, NVX‑CoV2373 demonstrated indication of antibodies that block binding of spike protein to receptors targeted by the virus, a critical aspect for effective vaccine protection.
Novavax is a biotechnology company based in Gaithersburg, MD, and is involved in the development, and commercialization of innovative vaccines to prevent serious infectious diseases. They also have an influenza vaccine in late-stage development.
Novavax was awarded $1.6 billion by the federal government as part of Operation Warp Speed.