- 03 January 2023
COVID drug Paxlovid was hailed as a game-changer. What happened?
Insufficient investment and fears about rebound and side effects are driving down use of a lifesaving antiviral.
Researchers say that the drug’s rollout has been hampered by worries about ‘rebound’ (the mysterious return of symptoms or detectable virus days after a person starts to feel better) and side effects — as well as by declining concern about the risk of COVID-19. Inadequate funding for distribution, the drug’s high price tag and the need for it be taken soon after infection have also slowed its uptake. As a result, physicians have prescribed the drug in only about 0.5% of new COVID-19 cases in the United Kingdom, and in about 13% in the United States, according to a report by the health-analytics firm Airfinity, based in London, UK. Even doctors have reported serious difficulties in helping their family members to obtain Paxlovid1.
Sentiment against the drug has persisted even as regulators globally have rescinded authorizations for monoclonal antibodies against COVID-19, leaving Paxlovid as one of the only tools to prevent death in high-risk individuals, says Davey Smith, an infectious-disease physician at the University of California, San Diego. “It’s a game-changer drug that has good efficacy, even in the setting of Omicron,” says Smith. “But rebound has been tagged as a reason not to take the drug, which is a shame.”
This underuse stems in part from misinformation and misconceptions about the drug, says Daniel Griffin, an infectious-disease physician at Columbia University in New York City.
To add to the confusion, worries have swirled about post-Paxlovid ‘rebound’, fuelled by high-profile cases in figures such as US President Joe Biden and and former US infectious-disease chief Anthony Fauci. Such publicity has had a chilling effect on the number of people seeking Paxlovid, says Smith.
But researchers have found that rebound often occurs even in people who don’t take Paxlovid3. Precise estimates for rebound incidence vary, depending on the population studied and the definition of ‘rebound’. But regardless of whether people take Paxlovid, Smith says, it’s common for them to experience either viral rebound — in which people test positive again — or symptom rebound, but not both at the same time4. Smith says that symptom rebound tends to be very mild, and is still far preferable to hospitalization or death.
In addition, Paxlovid can’t be taken with many other drugs and, in some people, makes certain foods taste bitter or metallic, both of which reinforce the perception that it’s toxic, Smith says. Treatment requires taking several pills twice a day for five consecutive days — which isn’t the easiest regimen to adhere to, Smith adds.
Such concerns have led health officials to point to hesitancy to explain why use of the drug has fallen short. But there are also systemic reasons, says Anne Sosin, a public-health-policy specialist at Dartmouth College in Hanover, New Hampshire.
Paxlovid relies on a robust COVID-19 testing infrastructure and access to primary-care physicians and pharmacies, she notes. This amplifies pre-existing disparities resulting from race and income.