The Serum Institute of India CEO Adar Poonawalla is hopeful that Covovax, another COVID-19 vaccine being manufactured by his company, will be launched in October for adults and for children by the first quarter of 2022.
Covovax is the brand name of Novavax, a US-based biotechnology company whose vaccines are yet to be rolled out in the US. In August last year, Novavax Inc. had announced a licence agreement with the SII for the development and commercialisation of Novavax in low and middle-income countries and India.
The latter has committed to supply 200 million doses of the Novavax vaccine between September and December. Here's everything you need to know about this much-anticipated vaccine.
In January, SII sought the Drugs Controller General of India's (DCGI) permission to conduct a small domestic trial of a new vaccine against COVID-19 developed by the US-based Novavax. Codenamed 'NVX-CoV2373', the Novavax is a prefusion protein coronavirus vaccine, which sets it apart from its key competitors like Moderna, Pfizer, Johnson & Johnson and AstraZeneca.
Such vaccines, use technologies based on genetic material that directs protein production, rather than delivering proteins directly. They rely on DNA loaded in disabled viruses or on messenger RNA to carry genetic instructions for building the spike protein, which allows the virus to latch onto and enter a cell.
Cells within a vaccinated person then produce the protein, alerting the immune system. But in protein vaccines, developers must construct their own version of the spike protein, in this case, it is made of moth cells and tree bark, which is harmless and can't cause COVID-19. When a person's immune system encounters the spike protein, it produces antibodies against it. This gives the person protection against COVID-19 infection.
Efficacy against variants
- The Novavax is being evaluated in two pivotal Phase 3 trials — a trial in the UK that demonstrated an efficacy of 96.4percent against the original virus strain, 86.3 percent against the Alpha (B.1.1.7) variant and 89.7 percent efficacy overall.
- The PREVENT-19 trial in the US and Mexico demonstrated 100 percent protection against moderate and severe disease and 90.4 percent efficacy overall.
- It is also being tested in two ongoing Phase 2 studies that began in August 2020 — a Phase 2b trial in South Africa that demonstrated 55 percent efficacy overall in HIV-negative participants and 48.6 percent efficacy against a newly emerging escape variant first described in South Africa.
- A Phase 1/2 is on in the US and Australia.
- The data of its effectiveness against the Delta variant is not known yet.
- As per a company release, published on August 6, a booster dose of Novavax is associated with a 4.6-fold increase in functional antibody titers (concentration).
Covovax and children
With the highly contagious Delta variant taking hold in communities across the country, parents are eager for their children to be vaccinated. In the US several COVID-19 vaccines are being studied in children with Pfizer-BioNTech and Moderna in the forefront.
Both companies launched their COVID-19 vaccine trials for kids as young as six months old in March, and expect to share the results by September. Meanwhile, Johnson & Johnson is collecting data about their COVID-19 vaccine for ages 12 to 17 and hopes to start studying ages 2 to 11 soon. Novavax on the other hand has only recently expanded its late-stage US trial to include pediatric patients and has enrolled more than 2,000 volunteers between 12 and 17 years old.
In India, only last month SII received DCGI approval to conduct phase 2/3 trials of Covovax on children aged 2 to 17 years with certain conditions. According to reports, the trials would cover 920 children, 460 each in the age group of 12-17 and 2-11 across 10 sites.
Is it better than its competitors?
In its Phase 3 trial, Novavax's has shown an efficacy that is closer to Pfizer-BioNTech (91.3 percent) and Moderna (90 percent). However, it is slightly higher than that of Covishield (76 percent) and Covaxin (81 percent). Russia's Sputnik V has an efficacy rate of 91.6 percent.
Dosage and side effects
The vaccination regimen calls for two 0.5 ml doses (5 microgram antigen and 50 microgram Matrix-M adjuvant) given intramuscularly 21 days apart. The side effects following the administration of the Novavax 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.
Storage and pricing
The vaccine is packaged as a ready-to-use liquid formulation in a vial containing ten doses. The vaccine is stored at two to eight degrees Celsius, enabling the use of existing vaccine supply and cold chain channels. Meanwhile, the vaccine will be supplied at a tentative price of Rs 1,114 per dose, but Poonawalla has recently said that the price will be decided at the time of launch.
Implication for India
With the SII committing to supply 200 million doses of the Novavax vaccine between September and December, and the government set to get 20 crore vaccine doses of Covishield, Covaxin and Sputnik V in August and 25 crore doses in September, it is likely to achieve its target of vaccinating all adults in the country by the end of December.
With inputs from agencies