Metformin’s impact on Long COVID reported worldwide

Thanks to international media coverage, people around the world are learning that the inexpensive and widely-available drug metformin reduces the incidence of Long COVID.

The COVID-OUT clinical trial reported a reduction in Long COVID incidence in participants taking metformin after COVID-19 infection, and the results were published in The Lancet Infectious Diseases on June 8, 2023. This was the first study to show that treatment immediately after COVID-19 symptoms could result in fewer cases of Long COVID, a condition that can last for months after the initial COVID-19 infection is cleared. Metformin is an inexpensive diabetes drug that has been shown to be extremely safe, even for pregnant women. Earlier results of the COVID-OUT study found that metformin was effective at reducing the severe symptoms of COVID-19. Together, these findings support the use of metformin for COVID-19 infection to reduce severe symptoms of the disease and the impacts of Long COVID.

Debate has surrounded the existence of Long COVID or “post-COVID condition” due to the variety of different symptoms reported and the lack of definitive diagnostic criteria and treatments. The COVID-OUT trial results on Long COVID thus support the “therapeutic validation” of Long COVID, as Dr. Jeremy Samuel Faust commented in The Lancet Infectious Diseases.

“The findings from the study by Bramante and colleagues are profound and potentially landmark on two distinct counts,” Dr. Faust wrote. “First, to our knowledge, this is the first high-quality evidence from a randomised controlled trial to show that the incidence of long COVID can be reduced by a medical intervention, metformin—an inexpensive treatment with which clinicians have ample experience. Second, the authors have, perhaps inadvertently, made an important contribution to medical epistemology. If a new disease has been sufficiently well characterised by clinicians so that it can be successfully modified by a therapy compared with placebo, then the entity must, from a practical standpoint, truly exist. Put differently, a treatment can only be effective if there is something to treat.”

The exciting news was picked up by media outlets across the globe in major markets and local publications. Coverage began when the pre-print was made public in December, 2022 (including significant coverage in The Atlantic and Time) and now that the peer-reviewed paper has been published (see US News & World Report, Yahoo, New Scientist, BMJ, and Large international markets in India and China also followed the results. The Parsemus Foundation is proud to have supported the COVID-OUT clinical trial.

“We hope the U.S. and other nations update their guidelines to include metformin as a treatment option for people with COVID-19,” Elaine Lissner, founder and trustee of the Parsemus Foundation, said.

For more information, visit our COVID-19 webpage.

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