Paxlovid does not quell long Covid symptoms: Stanford study

WASHINGTON - A 15-day course of Pfizer Inc’s antiviral Paxlovid didn’t provide significant relief for long Covid patients, researchers at Stanford University found.

Their trial didn’t find a statistically significant difference in the severity of six core symptoms both at 10 and 15 weeks post-treatment between the 102 patients administered the drug twice daily and 53 who were randomised to receive a placebo.

Stanford’s Stop-PASC study attracted interest from almost 800 potential participants.

It’s the first randomised clinical trial to test whether a longer course of the Covid-19 medication could alleviate prolonged symptoms including fatigue, brain fog, shortness of breath and body aches by rooting out the lingering coronavirus remnants thought to underlie at least a subset of people with long Covid, also known as post-acute sequelae of Covid-19, or PASC. 

The debilitating condition affects millions of people worldwide, some of whom have been suffering for more than four years, leading to an urgent need for effective treatments.

“This trial’s results do not reject the hypothesis that viral persistence may lead to PASC but they will help inform further studies in this area,” said clinical Associate Professor of medicine Linda Deng at Stanford, and colleagues wrote in the study, which was published on June 7 in the journal Jama Internal Medicine. 

The study was funded by Pfizer, which also collaborated on the design and execution of the trial.

Longer treatment durations, dose variations, changes in timing and patients with different long Covid symptoms should be investigated in larger studies, the researchers said.

Since the condition is likely driven by multiple disease pathways, combination therapies including antivirals and immunomodulators are worth exploring, they added.

“We do not anticipate the Stop-PASC study results will impact the continuation of our other planned collaborative studies evaluating Paxlovid for the potential treatment of long Covid,” Pfizer said.

It added that “these studies have been designed to better inform our collective understanding of this complex condition and potential treatment approaches.”

Paxlovid was approved for emergency use

by the US Food and Drug Administration in December 2021 for people at high risk of severe complications from acute Covid-19.

The pill, a combination of nirmatrelvir and ritonavir, got full clearance from the FDA in 2023 to treat mild-to-moderate Covid-19 in adults at risk of developing severe illness. BLOOMBERG