15-Day Paxlovid Regimen Fails to Deliver for People with Long COVID

Long COVID is a phenomenon emerging from the global spread of SARS-CoV-2, a strain of coronavirus causing COVID-19.

Seven million people died from COVID-19, though this is considered a serious undercount. Hundreds of millions of others were affected. Of those affected, scientists estimate that up to 10-20% developed long COVID. Long COVID is considered a chronic illness; symptoms can last days, weeks, months, or even years following COVID-19 infection. Yet, despite COVID long-haulers’ appeals for more research and care, our understanding of long COVID remains woefully minimal.

Researchers are, however, trying to identify treatment interventions to reduce the symptoms and severity of long COVID symptoms. One of these options is Paxlovid (nirmatrelvir/ritonavir). Paxlovid is currently approved to treat mild-to-moderate COVID-19 in people with a high risk of developing severe symptoms or requiring hospitalization. Researchers wondered whether Paxlovid could contribute to better long COVID outcomes.

Studying Long COVID

Tristan Manalac reports that Stanford Medicine researchers conducted the Phase 2 STOP-PASC study to evaluate Paxlovid in this setting. 155 participants enrolled. Of these, 153 had been vaccinated for COVID-19; the remaining two had not. All participants were infected with COVID-19 at least sixteen months before the trial. Still, they faced debilitating fatigue, brain fog, shortness of breath, issues with cognitive and physical function, cardiovascular issues, and gastrointestinal distress.

During the course of the trial, participants were split into different groups. Some individuals received Paxlovid; others received ritonavir with a placebo. The treatment course was twice-daily for 15 days. Researchers then assessed the therapy’s impact after a 10-week period.

Data published in JAMA Internal Medicine shows that:

  • Paxlovid was safe and relatively well-tolerated. Most side effects were mild in nature.  An article from Stanford also notes that melanoma, bone fracturing, and anemia were seen in the Paxlovid arm, but these were deemed unrelated to treatment. However, an instance of hepatitis in the placebo arm was potentially related to the trial.
  • In terms of efficacy, Paxlovid was not more effective than the placebo. No statistically significant difference between the two emerged. Both had similar effects on the six “main” symptoms evaluated in the study.

Researchers believe that future research could show clinical benefit, but more studies are required. The uncertainty of long COVID challenges research. For example, long COVID has a myriad of symptoms in addition to those listed above. A lingering cough, chest pain, changes in taste and smell, joint pain, rashes, and menstrual changes are just a few of the over 200 symptoms associated with this chronic illness. Do only some symptoms respond to antivirals? Is longer treatment needed? These questions could help researchers hone future studies.

Jessica Lynn

Jessica Lynn

Jessica Lynn has an educational background in writing and marketing. She firmly believes in the power of writing in amplifying voices, and looks forward to doing so for the rare disease community.

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