Paxlovid (nirmatrelivir tablets, ritonavir tablets, co-packaged for oral use), 150 mg. / 100 mg. Dose Pack
date: label: date made
content: 2024
label: product expiration date
content: 2025-05
name: label: maker
content: Pfizer Inc.
notes: label: Description
content: Paxlovid, manufactured by Pfizer, is the first oral antiviral to be approved by the FDA to treat COVID-19. Paxlovid consists of two drugs, nirmatrelvir tablets and ritonavir tablets, co-packaged for oral use. The full regimen consists of three tablets (two nirmatrelvir, 150 mg., and one ritonavir, 100 mg.), every morning and evening for five days. Alternately, a half-strength regimen is available consisting of one tablet of nirmatrelvir, 150mg., and one ritonavir, 100 mg. Paxlovid is most effective when taken within the first several days of the appearance of symptoms.
label: Description
content: Pfizer’s project to develop an antiviral began as the COVID-19 pandemic shut down the country on March 13, 2020. The company focused on an oral protease inhibitor. Protease inhibitors had been used successfully to treat other viral infections such as HIV/AIDS and Hepatitis C. Protease is an enzyme found in viruses that is critical for viral replication – shutting down the enzyme will stop the virus from spreading within the body. In addition, unlike the spike protein, which is the target for the vaccine, the protease molecule is relatively stable (“highly conserved”). Thus, a drug that targets protease will continue to be effective even as the virus mutates.
label: Description
content: As with the work on the COVID-19 vaccine, development of an antiviral for COVID-19 benefitted enormously from prior research on corona viruses – specifically the SARS virus. During the 2003 SARS outbreak, Pfizer had developed an effective protease inhibitor which became the starting point for nirmatrelvir (Paxlovid’s antiviral component) as the main protease structure was similar in both corona viruses. The challenge faced by the Pfizer team was to make the antiviral orally available (the SARS antiviral had to be administered intravenously). This was accomplished by tinkering with the molecular structure to identify and replace “problem” reactive groupings without losing potency. The company reported that they synthesized 800 different molecules for initial testing – an accomplishment that would be near impossible without the enormous resources of a big pharmaceutical company. The firm also shrank the development timeline (dubbed “lightspeed” development) by running different phases of design, testing, and clinical trials concurrently. In the end it took just 17 months from the first laboratory synthesis of nirmatrelvir in July 2020 to the FDA’s Emergency Use Authorization for Paxlovid in December 2021.
label: Description
content: After the clinical trials established the effectiveness of Paxlovid (89% reduction in COVID-19 hospitalizations or deaths if taken within 5 days) the U.S. government quickly purchased 20 million courses. Over the next two years, December 2021 to December 2023, the government continued to provide the medication for free. Paxlovid received full FDA approval in May 2023 and the Emergency Use Authorization (EUA)-labeled Paxlovid was phased out (as of March 8, 2024).
label: Description
content: References:
label: Description
content: Regalado, A. “How Pfizer made an effective anti-covid pill.” MIT Technology Review, February 4, 2022.
label: Description
content: Allais C, Connor CG, Do NM, Kulkarni S, Lee JW, Lee T, McInturff E, Piper J, Place DW, Ragan JA, Weekly RM. Development of the Commercial Manufacturing Process for Nirmatrelvir in 17 Months. ACS Cent Sci. 2023 Mar 29;9(5):849-857.
label: Location
content: Currently not on view
place: label: place made
content: China
label: place made
content: Italy
topic: label: associated subject
content: Treatment of COVID-19
label: related event
content: COVID-19 Pandemic, 2020-2023
setName: label: See more items in
content: Medicine and Science: Medicine
label: See more items in
content: Health & Medicine
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 2024.0082.01
label: catalog number
content: 2024.0082.01
label: accession number
content: 2024.0082
objectType: label: Object Name
content: pharmaceutical
physicalDescription: label: Physical Description
content: nirmatrelivir, 150 mg. per tablet (drug active ingredients)
label: Physical Description
content: ritonavir, 100 mg. per tablet (drug active ingredients)
label: Physical Description
content: cardboard; paper; plastic; foil (packaging materials)
label: Measurements
content: overall (box): 3 3/8 in x 3 in x 2 5/8 in; 8.5725 cm x 7.62 cm x 6.6675 cm