What is Novavax Vaccine?
Novavax is a COVID-19 vaccine created using recombinant nanoparticle technology which contains the full-length SARS-CoV-2 spike protein and a Matrix-M1 adjuvant (an additional vaccine component that boosts the immune response).
Pre-clinical trials of Novavax COVID-19 vaccine candidate were conducted in baboons and mice. In animal models, the vaccine-induced high levels of anti-spike antibodies and neutralizing antibodies, which exceeded the responses measured in humans recovered from natural COVID-19 infection.
Phase 1 clinical trials were conducted in 131 healthy adults aged 18-59 years in Australia and the United States of America (USA). The study assessed the safety and immunogenicity of two doses (low dose 5-μg and high dose 25-μg) with or without Matrix-M1 adjuvant in healthy adults aged 18 to 59 years, compared to a placebo. Overall, the vaccine elicited a good immune response, with immunogenicity comparable in both low and high-dose groups. An enhanced immune response was seen in the adjuvant group.
A phase 2 trial in Australia and the USA expanded the age of participants to include 1,288 participants aged 18-84. Results of this study indicated that a two-dose regimen of 5-µg NVX-CoV2373 administered 21 days apart was the optimal vaccine dose to proceed to phase 3 trials.
How safe is Novavax Vaccine?
Novavax Vaccine is a safe vaccine, preliminary phase 3 results indicate that side effects following administration of the Novavax COVID-19 vaccine have been generally mild to moderate, and short-lived. Injection site pain and tenderness, as well as fatigue, headache, and muscle pain, were the most commonly reported side effects. The incidence of serious adverse events was low and reported in similar numbers in both the vaccine arm and placebo group.
Regulatory authorities have thoroughly assessed the data on the safety and efficacy of the vaccine and have recommended its use for people aged 18 and above.
However, safety data is currently limited for persons above 65 years of age (due to the small number of participants of this age group in clinical trials). However, the trial data indicate that the vaccine has an acceptable safety profile for this age group and WHO recommends the vaccine for use in persons aged 65 years and over.
How effective is Novavax Vaccine?
Following several clinical trials, most regulatory authorities including the European medicine regulatory agency have affirmed the efficacy of the Novavax Vaccine and have granted conditional marketing authorization for Novavax’s COVID-19 vaccine in people 18 years of age and above.
Nuvaxovid is the fifth vaccine recommended in the EU for preventing COVID-19.
Should pregnant women take the Novavax vaccine?
Data regarding the safety and efficacy of the use of the Novavax vaccine in pregnant women is not yet available. However, based on previous evidence from other protein-based vaccines during pregnancy, efficacy is expected to be comparable to non-pregnant women of a similar age.
WHO recommends the use of the COVID-19 vaccine in pregnant women when the benefits of vaccination to the pregnant woman outweigh the potential risks. To help pregnant women make this assessment, they should be provided with information about the risks of COVID-19 in pregnancy, the likely benefits of vaccination in the local epidemiological context, and the current limitations of safety data in pregnant women. WHO does not recommend pregnancy testing prior to vaccination. WHO does not recommend delaying pregnancy or terminating a pregnancy because of vaccination.
Who else can take the Novavax vaccine?
Vaccination is recommended for people living with conditions that have been identified as increasing the risk of severe COVID-19, including cardiovascular disease, respiratory disease, diabetes, liver disease, obesity, and neurodevelopmental and neurodegenerative conditions.
The vaccine can be offered to people who have had COVID-19 in the past. Available data shows that symptomatic reinfection from the same variant is unlikely for up to 6 months after infection. Those with documented infection may therefore choose to delay vaccination to nearer the end of this period, especially when vaccine supply is limited, to allow others priority for vaccination.
WHO recommends the same use of Novavax vaccine in breastfeeding and non-breastfeeding women. Data are not available on the potential benefits or possible risks of the Novavax vaccine to breastfed children. However, as Novavax vaccine is not a live virus vaccine, it is biologically and clinically unlikely to pose a risk to the breastfeeding child. WHO does not recommend discontinuing breastfeeding because of vaccination.
Persons living with human immunodeficiency virus (HIV) or who are immunocompromised are at higher risk of severe COVID-19 disease. There are not enough data at present to allow assessment of the efficacy or safety of this vaccine for people living with HIV. It is possible that the immune response to the vaccine may be reduced, which could lower its clinical effectiveness. In the interim, however, given that the vaccine is nonreplicating, people living with HIV that is well controlled may be vaccinated with the standard primary series of 2 doses, when part of a group is prioritized for vaccination.
Who is the Novavax vaccine not recommended for?
Individuals with a history of anaphylaxis to any component of the vaccine should not take it.
Persons with acute PCR-confirmed COVID-19 should not be vaccinated until after they have recovered from acute illness and the criteria for ending isolation have been met.
Anyone with a body temperature over 38.5°C should postpone vaccination until they no longer have a fever.
Most children and adolescents are at very low risk of severe COVID-19. Safety and immunogenicity data are currently being generated for those aged under 18 years. Until this data are available, vaccination of persons under the age of 18 is not recommended.
What is the recommended dosage of the Novavax vaccine?
WHO recommends the use of the Novavax vaccine as 2 doses (0.5 ml) given intramuscularly. The two doses should be administered at an interval of 3-4 weeks.
WHO recommends that severe and moderately immunocompromised persons should be offered an additional dose of vaccine. This is due to the fact that this group is less likely to respond adequately to vaccination following a standard primary vaccination series and are at higher risk of severe COVID-19 disease.
How does this Novavax vaccine compare to other COVID-19 vaccines already in use?
It is impossible to compare vaccines head-to-head due to the different approaches taken in designing the respective studies, but overall, all of the vaccines that have achieved WHO Emergency Use Listing are highly effective in preventing severe disease and hospitalization due to COVID-19.
Does the Novavax vaccine work against new variants of SARS-CoV-2 virus?
In a Phase 3 study conducted in the USA and Mexico during a period in which multiple variants were in circulation, vaccine efficacy against mild, moderate, or severe COVID-19 was 90%.
In view of these findings, WHO recommends the use of Novavax vaccine according to the WHO Prioritization Roadmap, even if currently recognized Variants of Concern (VOC) are present in the country. If new VOCs emerge for which vaccine performance is compromised, these recommendations will be updated accordingly. There are insufficient data still for Omicron.
Does it prevent infection and transmission?
As there is not currently sufficient evidence to date to evaluate the impact of the vaccine on transmission, public health, and social measures must continue, including use of face masks, physical distancing, hand washing, appropriate ventilation, and other measures as appropriate in particular settings, depending on the COVID-19 epidemiology and potential risks of emerging variants. Government advice on public health and social measures should continue to be followed by both vaccinated and unvaccinated individuals.
