PHILADELPHIA (KYW Newsradio) — The pressure is on for Pfizer, Moderna and Johnson & Johnson to make more vaccine, faster.
“Most vaccines that we are used to are either actual virus particulars, alive or dead, or a part of that virus particular - a protein,” says Dr. Jason Diaz, an assistant professor at La Salle University with a background in viruses and vaccines.
The Pfizer and Moderna COVID-19 vaccines are mRNA vaccines. The mRNA is wrapped in a special lipid bubble which delivers the mRNA into the cell. And there’s a little bit of sugar and other components in there too to make sure the vaccine stays fresh.
Diaz says that’s one of the reasons why the vaccine takes longer to make. “I think a lot of people are thinking, is it that the lipids are crazy or is mRNA hard to make? Actually, all those things are pretty straightforward. The bottleneck really is in the process of mixing the RNA with the lipids.”
He says the materials themselves aren’t all that odd, but Pfizer and Moderna’s vaccine requires a special process.
“For the mRNA vaccines - there’s this extra step of now taking that purified product and mixing it just perfectly with the correct balance of lipids and then putting that into some solution. Whereas for the HPV vaccine, you can just take the protein you’ve purified out of cells and mix it with whatever the final formulation is and stick it into a person.”
Diaz says the vaccine needs to be consistently correct “every single time for millions of millions of doses.” But he adds the other bottleneck people don’t think about as much is in the supply chain.
“(It’s) a complex interplay of all the players who have to receive it, track it, store it and then send it out - and any kind of hiccups in any of those can have ripple effects upstream and downstream.”
Diaz is extremely optimistic about the Johnson & Johnson vaccine. He says the one-dose shot that doesn’t need to be stored at freezing temperatures could open doors for more pharmacies and providers.
“I think the (Johnson & Johnson vaccine) is really going to push vaccination up to where it needs to go.”