A COVID Pill

Maybe you know someone who has gotten the Pfizer COVID pill. It's the first one given emergency approval by the FDA. PAXLOVID disrupts the virus's ability to replicate within the human cell and is nearly ninety percent effective at preventing hospitalization. Merck also has a pill approved but is just thirty-three percent effective.

PAXLOVID works by preventing the virus from making the proteins necessary for viral reproduction. It's the same approach that's successfully treating HIV and Hepatitis C. PAXLOVID combines two drugs, the PF-07321332 which is new and an older HIV drug, Ritonavir. Ritonavir slows the body's metabolism of the new drug so that it can remain longer in the body to do its work. The new PF drug originated during the SARS outbreak of two thousand two that killed fifteen percent of infected people. When the virus disappeared, the drug was shelved.

To see if the drug could work on SARS-CoV-2, Pfizer scientists discovered it had nearly identical active sites to the SARS virus in the machinery necessary for viral replication. They made minor changes to the drug and tested it in cells against both viruses and it was able to kill both! After PAXLOVID was approved in December the White House ordered twenty million doses with most of it arriving this summer.

Although it's useful against COVID-nineteen, vaccines are still our first line of defense. This is especially true since the pill won't be widely available for months.