
“The story of Paxlovid starts back in 2003, when the first SARS outbreak took place in Asia. Looking to develop a medication that could stop its spread, Pfizer started researching drugs that could block the action of a viral protein called a protease, which is necessary for the virus to replicate itself inside the host cell. One advantage of a medication like this, compared to a vaccine, is that it attacks a vulnerability of the virus that doesn’t mutate in the same way that the spike proteins targeted by vaccines do. That means it’s likely to be equally effective against all variants.
Pfizer’s preliminary research didn’t get too far before SARS petered out. But when SARS-CoV-2 popped up, they put the idea back on the fast track, ultimately trying out more than 600 candidate compounds in test tubes. The most promising were then tested in animals before being winnowed down once more for human trials.
Pfizer started testing Paxlovid in September 2021, enrolling patients who were suffering from mild to moderate symptoms — meaning they hadn’t been hospitalized yet — and were at high risk of their symptoms turning severe, either due to being over 65 or having comorbidities like obesity or diabetes. Pfizer expected the study to last into 2022, but was able to end the trial early because the results were so spectacular. It reduced hospitalizations in those who caught COVID by 90 percent and eliminated deaths entirely. Among the thousand or so trial participants who took the drug, none died, versus seven people in the control group.”
What Happened to Paxlovid? The COVID antiviral arrived too late for the Omicron wave, but it remains a powerful weapon via The Intelligencer.