When the coronavirus pandemic began, the challenge for Pfizer and BioNTech wasn’t just creating a Covid-19 vaccine – they had to make it, by the hundreds of millions.
This was no small matter. Until the end of last year, no mRNA vaccine had ever been approved, and no company had ever made such a vaccine to scale.
Pfizer has now shipped more than 100 million cans to the US and this week achieved its goal of having 120 million cans released and ready for shipping by the end of March.
For Mike McDermott, Pfizer’s President for Global Supply, the mission is more cans. Billions of them.
“Our goal was to work around the clock and give as many doses as possible. I actually don’t even have a production target, ”McDermott told CNN chief correspondent Dr. Sanjay Gupta during an exclusive tour of his Kalamazoo, Michigan manufacturing facility in March. “Our goal is to produce as much as possible to get to 2 billion cans as quickly as possible this year.”
Pfizer / BioNTech’s global goal is 2.5 billion doses by the end of the year.
Big game of chance
Pfizer reached its early milestones with significant upfront investment and had no guarantees.
Pfizer was part of Operation Warp Speed as a potential supplier of Covid-19 vaccines and had an initial purchase agreement of 100 million doses. However, the company did not receive federal funding for research or development of the vaccine.
While Pfizer was able to reuse some of its equipment at its main manufacturing facility in Kalamazoo, most of what is there now wasn’t there a year ago.
“Pfizer put nearly $ 2 billion at risk on the overall program. On manufacturing, my team spent $ 500 million before we even dropped out of clinical trials. So everything is completely at risk. We didn’t know if we would have a product that would work, ”said McDermott.
Before Pfizer decided on its final vaccine candidate, it considered four different options. That meant McDermott and his team had to be ready to go in any direction.
“I think we’re going to have dinner tonight and have to get dessert ready, but I don’t know which dessert we have. So you just buy ingredients, ”he said. “Maybe we’ll make a cake, maybe we’ll make brownies. Let’s bring in the standard materials we need. So this pantry was pretty, pretty expensive to fill up. “
According to McDermott, one of the biggest rate-limiting steps in this production was the availability of raw materials and especially lipids, the fatty substance that safely houses the mRNA until it can get into our cells.
“Lipid nanoparticles have not been used in any large commercial product. So the lipid suppliers weren’t very large. So we’re working very closely with them to build more lipid capacity and actually make lipids at this location in Kalamazoo, Michigan, ”said McDermott.
The heart of the mRNA
Pfizer / BioNTech’s Covid-19 vaccine can be described simply as mRNA housed in a lipid coating.
The heart of this whole machine is what is known as an impingement jet mixer, ”said McDermott as he twisted it around his fingers.
The impingement jet mixer, also known as a tea stirrer, simply pumps lipids on one side and mRNA on the other, forcing them together with 400 pounds of pressure. This is what creates the lipid nanoparticle that is essentially the vaccine.
These are not just any lipids, Pfizer / BioNTech had to develop the right combination of four different lipids that not only protect the mRNA on its way to the cells, but also release it once it gets there.
While the process of making lipid nanoparticles is not new, McDermott said the challenge was to scale that process up.
“When someone showed me this impingement jet mixer for the first time, I said, ‘You can’t be serious? ‘How could you get billions of cans through here? So my confidence was actually pretty low. Not that it was possible, I knew it worked on this scale, but how do you multiply it? “
McDermott’s first thought was to get bigger and make a large tea stirrer to allow more volume to pass through. When that didn’t work, they replicated the quarter-size mixers and deployed technology to ensure efficiency and scale up production.
“There is a computer system that runs the entire apparatus, making sure you have the exact amount of flow and pressure. And that allowed us to get more production out. Although this size is small, we were able to really enlarge our original design for this machine. We are currently working with four times the capacity. “
Make it modular
Part of what has allowed Pfizer to keep making room for these new formulation suites has been its strategy of using pre-built constructions.
In its 1,300-acre Kalamazoo facility, Pfizer is installing around 13,000 square feet of modular space, which will be built first in Texas and then shipped to Kalamazoo.
“We had planned to expand our formulation capacity. The question was, how can we do this quickly? If we had built it wall by wall on site, it would have taken us a year. If we make it modular, we can cut that in half, ”says McDermott.
It’s surprisingly easy to put any room in its place. With the help of compressed air – think of an air hockey table – you can simply slide these into place. Then the rooms can be connected to the power supply, sterilized and put into operation.
With each of these improvements, Pfizer says production has increased from 3 to 4 million vaccine doses per week to 13 million doses per week. The company expects to double that again by the middle of the year. That means roughly 100 million doses per month and the ability to meet the target of 300 million total doses to be delivered to the US government by July.
McDermott says the past 12 months have been “like nothing I’ve ever seen in my career”.
“When I was a kid, my father worked for NASA,” said McDermott. “He was fortunate enough to be mission control in Houston when Neil Armstrong stepped onto the moon at that amazing moment.
“I could never imagine having such a moment in my life. Correct? What is the likelihood that something like this would ever happen again? “
Then came December 13, 2020 – the day the U.S.’s first coronavirus vaccine, the first step in ending the pandemic, left the facility.
“The day we shipped the first cans from this website it raced over me, so that was my moment,” said McDermott. “That was our moon shot.”
But McDermott says the vaccine supply is always on his mind and they need to prepare for the future – and that means coronavirus variants.
While there is no evidence that people immunized with Pfizer’s vaccine are less protected against the current variants, the company has begun testing a third dose of its current vaccine.
Pfizer and BioNTech state that they are currently discussing possible testing of a vaccine that has been modified to protect against variants in a phase 1/2 study with regulators.
The company’s next big leap is to be ready to make it available to patients when needed.
Pfizer’s goal, says McDermott: To be able to develop a new variant-specific vaccine, get it through production, and get it to patients within a few months.