NOVAVAX Inc says its experimental COVID-19 vaccine showed immune response and protection against the highly contagious coronavirus variant originally identified in South Africa in a clinical trial. The vaccine, NVX-CoV2373, is being tested in multiple trials but has yet to be authorized for use in any country. Novavax also said studies in mice and baboons found that a different vaccine specifically targeting the South African variant now known as Beta produced immune response and protection, and that it expected to conduct further clinical testing of the Beta-focused vaccine in the fall. The company said testing of blood serum of thirty…