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Paxlovid helps fight COVID, but it does not prevent long-COVID symptoms

A recent study conducted by a team from UC San Francisco has shed new light on the efficacy of Paxlovid (Nirmatrelvir-ritonavir) in preventing long COVID in vaccinated individuals experiencing their first COVID-19 infection.

The study, published in the Journal of Medical Virology, brings forth some intriguing findings.

Paxlovid and long COVID study

Previously, Paxlovid had been recognized for its effectiveness in treating high-risk, unvaccinated individuals during the acute phase of COVID-19.

However, its role in reducing the risk of long COVID, particularly in vaccinated individuals, remained uncertain.

The UCSF research team focused on a group of vaccinated individuals from the UCSF Covid-19 Citizen Science study.

These participants reported their first positive COVID-19 test between March and August of 2022 and were not hospitalized.

The study involved a comparative analysis between those who took oral Paxlovid during their infection and those who did not.

Key results and insights

In December 2022, participants completed a follow-up survey, detailing their experiences with long COVID symptoms, any COVID rebound symptoms, and the duration of their test positivity.

The results were revealing. Approximately 16% of participants treated with Paxlovid experienced long COVID symptoms, closely aligning with the 14% in the non-treated group.

Common symptoms included fatigue, shortness of breath, confusion, headache, and changes in taste and smell. Interestingly, the severity of long COVID symptoms did not differ significantly between those treated with Paxlovid and those who were not.

A notable aspect of the study was the higher incidence of acute symptoms rebound and test-positivity post-Paxlovid treatment than previously reported.

Among those who initially responded well to Paxlovid, 21% experienced rebound symptoms. In this subgroup, 10.8% reported enduring one or more long COVID symptoms, compared to 8.3% of those without rebound symptoms.

Additionally, 25.7% of participants who underwent repeat antigen testing reported rebound test positivity. Overall, 26.1% of the participants experienced either rebound symptoms or test positivity.

Paxlovid and the future of long COVID

Dr. Matthew Durstenfeld, MD, MAS, a cardiologist and assistant professor of Medicine at UCSF and the study’s first author, expressed surprise at the findings.

“We found a higher proportion with clinical rebound than previously reported but did not identify an effect of post-treatment rebound on long COVID symptoms,” he said.

Durstenfeld added, “Our finding that Paxlovid treatment during acute infection is not associated with lower odds of long COVID surprised us, but it is consistent with two other rigorously conducted studies finding no difference in post-COVID conditions between 4 and 6 months after infection.”

In summary, this study provides crucial insights into the ongoing battle against COVID-19, particularly in understanding the role of therapeutics like Paxlovid in managing long-term effects.

While the treatment is effective in acute cases, its impact on long COVID remains ambiguous, warranting further research and investigation.

The full study was published in the journal Medical Virology.


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