“The hardest thing about making a vaccine is mass-producing it. You have to have the right buffering agent, the right stabilizing agent. You have to have the right vial. You have to do real-time stability studies to make sure that when the vaccine leaves the manufacturing plant, that the time it takes to get from the tarmac to the person's arm does not cause any problems. Because, remember, when you're shipping vaccines, they're going to be exposed to high temperatures and low temperatures, and you have to make sure that you have a stable product.”