The company’s vaccine against Covid-19 has been a year in the making, Dr. Gregory Glenn, president of research and development for Novavax, told CNN. The work began even before the world realized it faced a pandemic.
How Novavax’s vaccine works — using moth cells
These knob-shaped structures are what the virus uses to connect to human cells, causing infection. Getting the immune system to recognize and “remember” those spike proteins is key in how a vaccine helps protect against Covid-19.
Yet the way various coronavirus vaccines do that can vary.
These virus-like nanoparticles were harvested to make Novavax’s vaccine.
“The whole idea of the vaccine is to show the immune system something that looks, tastes and acts like a virus, with the exception that it doesn’t make you sick. So we made the spike protein. We put it in a particle — basically, like a soap bubble — and it’s the size of the virus,” Glenn said.
“It’s not infectious. We never touch the coronavirus itself,” he added. “Then that is given to people, and they make an immune response that’s very much focused just on the spike — and I would say, the hallmark of our vaccine is it gives a very strong immune response with very few side effects, and the dose is very small and the vaccine can be stored with normal refrigerated temperatures.”
That’s different from the Covid-19 vaccines made using messenger RNA carried in fatty particles called lipids. They’re more fragile and must be kept frozen.
The two mRNA vaccines that were authorized last year in the United States — Pfizer/BioNTech and Moderna — both use genetic material to stimulate an immune response.
When the vaccine is injected in a person’s arm, that genetic material gets taken up by cells in the arm muscle, which then follow the genetic instructions to make tiny pieces of the spike protein. Those little proteins stimulate an immune response, generating antibodies and immune cells that remember what they look like and that will be ready to respond quickly in case of a fresh attack.
Johnson & Johnson’s single-shot vaccine, which was authorized in February, uses a weakened common cold virus as a vector to carry the genetic instructions into arm cells, and they make the pieces that look like part of the coronavirus spike protein.
‘We were a small company’
Novavax expects to apply for emergency use authorization for its Covid-19 vaccine sometime in the second quarter of this year. But the company is already manufacturing the vaccine at 10 sites in eight countries — with two sites in the United States: North Carolina and Texas.
“They’re all at different stages,” Glenn said. “Some are earlier, but all are up and running and working on the vaccine. So, we expect to have a very large capacity.”
Novavax’s coronavirus vaccine was not among the first authorized in the United States because the company had to build the staff needed to develop such a new vaccine, Glenn said.
“We were a small company,” he said, in comparison with some of the larger vaccine makers such as Pfizer and Johnson & Johnson.
“We had to recruit people, and our funding was kind of low,” he said. “In addition to all the challenges of developing the vaccine, which is really complicated, we had the challenge to build a company.”
But Novavax has “reached a really good point now,” Glenn said.
Novavax vaccine found to have high efficacy
Novavax’s UK trial, with more than 15,000 participants ages 18 to 84, found that the vaccine had an efficacy of 96.4% against mild, moderate and severe disease caused by the original coronavirus strain and 86.3% against the B.1.1.7 variant first identified in the United Kingdom, the company said.
Novavax’s UK trial also showed that 14 days after the first dose, the vaccine efficacy was 83.4% in the trial, Novavax said.
Novavax expects to see similar trial results in the United States — especially as the B.1.1.7 variant continues to circulate, Glenn said.
“In the UK, the strain called B.1.1.7 became predominant and that strain looks like it is more severe in terms of causing more deaths than the original strain. That strain is kind of taking over in the US too. Some people are expecting that by April for all the virus or most of the virus to be this new variant B.1.1.7,” Glenn said.
“We are confirming our high efficacy against that strain as 86%,” Glenn said. “That’s really encouraging for our US data. It suggests our US trial, even if the virus evolves, will look very good.”
The company also noted that in an analysis of a smaller-scale Phase 2b trial in South Africa, where the B.1.351 variant was first identified. The vaccine had an efficacy of 55.4% among HIV-negative people.
Across both trials in the United Kingdom and South Africa, the vaccine offered 100% protection against severe Covid-19 resulting in hospitalization or death, Novavax said.
The vaccine also was well tolerated with few severe or serious adverse events in both the UK and South Africa trials, according to the company.
“Importantly, both studies confirmed efficacy against the variant strains,” Erck said.
“It’s a remarkable achievement to have so many candidates either already approved or showing such positive results ahead of an application to the regulators,” said Head, who is not involved in the Novavax studies.
“One note of caution is the observed lower effectiveness against B.1.351 variant of concern, as first observed in South Africa. This shows the impact variants can have upon the pandemic response and thus is a strong argument for keeping cases as low as possible whilst the burden of COVID-19 is high,” he said.
“However, there is still a clear protective effect there in the Novavax trial, and data from across all the COVID-19 vaccines suggests that they will be hugely protective against severe illness from all variants, which is still an excellent outcome.”