US biotech company Novavax announced Tuesday that its experimental covid-19 vaccine elicited a robust immune response in its early testing stage, producing more antibodies than are present in recovered patients and with generally tolerable side effects.
Last month, the United States government awarded the company $ 1.6 billion to develop and finance the vaccine, however its product in temporary terms is behind the development of other companies such as Moderna and AstraZeneca, which entered the final stages of their essays.
Novavax reported that phase one stage of its placebo-controlled trial involved 131 healthy adults aged 18-59 years, who received two-dose doses of five and 25 micrograms.
Side effects included pain at the injection site, headache, fatigue, and muscle pain. These were classified as mild to moderate, and none were severe.
After the first dose, all subjects who received the vaccine developed antibodies that block the SARS-CoV-2 “spike protein,” which uses the virus to bind to cells.
Most also developed “neutralizing antibodies” that are more powerful and prevent viruses from infecting cells.
After receiving a dose administered 28 days later, all participants had the most potent neutralizing antibodies. Antibodies are proteins that fight infections caused by the immune system.
Novavax reported that the lowest dose was compared to the highest, which is important in mass production and because lower doses cause fewer side effects.
In addition to antibodies, the immune response appears in the form of T cells, white blood cells that have the ability to kill infected cells and are believed to play an important role against covid-19.
Novavax said it looked for these cells in a subset of participants and found that they were present.
The trial was conducted at two sites in Australia.
Novavax has not yet shared the detail of its findings, but said it was submitting the research for publication in a peer-reviewed journal and on the medical preprint site medrxiv.org.
The final phase test of her vaccine, called NVX-CoV2373, will take place in the fall, which begins in the United States in September.