A protein vaccine differs from the mRNA vaccines (Pfizer and Moderna) and those with a viral vector (Covaxin, AstraZeneca and Johnson & Johnson). For this reason, it could trigger sceptics and ‘soft’ no vaxes who so far have not come close to immunization against the coronavirus. How does the Novavax vaccine work? How is it different from vaccines that are already widely used?
The immune system identifies the protein as foreign and makes natural defenses – antibodies and T cells – against it. If the vaccinated person later comes into contact with the coronavirus, the immune system will recognize the Spike protein on the virus and be ready to attack it. Antibodies and immune cells can protect against Covid by working together to kill the virus, prevent its entry into cells and destroy infected cells.
The results of two main clinical studies reviewed by EMA experts show that Nuvaxovid has been shown to be effective in preventing Covid-19 in people over 18 years of age. The trials involved a total of over 45,000 people. In the first study, about two-thirds of the participants received the vaccine, and the others were given a placebo injection; in the other, the participants were equally divided between Nuvaxovid and placebo.
The first study, conducted in Mexico and the United States, found a 90.4% reduction in the number of symptomatic cases of Covid-19 from 7 days after the second dose in people who received Nuvaxovid (14 patients out of 17,312 people) compared to those who received placebo (63 out of 8,140). This means the EMA notes that the vaccine was 90.4% effective in this study.
The second study conducted in the UK also showed a similar reduction in the number of symptomatic cases of Covid-19 in people who received Nuvaxovid (10 patients out of 7,020 people) compared to the group that was given placebo (96 out of 7,019). Hence with an effectiveness of 89.7%.
Taken together, therefore, the results of the two studies show the efficacy of the Nuvaxovid vaccine of about 90%. The original Sars-CoV-2 strain and some disturbing variants such as Alpha and Beta were the most common viral strains circulating during the trials. Currently, EMA points out that limited data is available on the effectiveness of Nuvaxovid against other variants of concern, including Omicron.
In studies, Ema explains that side effects are seen with Nuvaxovid were generally mild or moderate and disappeared within a couple of days after vaccination. The most common were tenderness or pain at the injection site, fatigue, muscle aches, headache, general discomfort, joint pain, and nausea or vomiting.