The long-term sequelae of SARS-CoV-2 coronavirus infection are known as Persistent COVID and they have become a public health problem worldwide because they can affect millions of people and at the moment there are no treatments that have proven effective in preventing or reversing their symptoms. Therefore, any novelty in this regard generates expectation and hope.
A study has now found that people who follow a two-week treatment with metformin –a drug used to combat type 2 diabetes– after testing positive for SARS-CoV-2 have a 40% less risk of prolonged COVID over the next 10 months compared to people given a placebo. The results have been published in The Lancet Infectious Diseases.
“Long-term COVID is a significant public health emergency that can have lasting impacts on physical health, mental health, and the economy, especially in socioeconomically marginalized groups. There is an urgent need to find possible treatments and ways to prevent this disease. Our study showed that metformin, a drug that is safe, low-cost, and widely available, substantially reduces the risk of being diagnosed with long-term COVID if taken when first infected with the coronavirus. This trial does not indicate whether metformin would be effective as a treatment for those who already have long-term COVID”, stated the first author, the Dra. Carolyn Bramantefrom the University of Minnesota School of Medicine (USA).
Metformin prevents the replication of the SARS-CoV-2 coronavirus
The people who participated in the trial were over 30 years old, had tested positive for the coronavirus in the last three days, and were more at risk of developing severe COVID-19 for being overweight or obese. None were hospitalized because of the infection. The study took place between December 2020 and January 2022 and included 1,126 patients who received either metformin or an identical placebo pill. Participants were followed for 10 months and data were self-reported via a self-report questionnaire every 30 days.
Metformin substantially reduces the risk of being diagnosed with long-term COVID if taken when first infected with the coronavirus
Metformin prevented more than 40% of persistent COVID cases in the trial; 6.3% (35/564) of participants who received metformin reported a prolonged COVID diagnosis within 10 months of follow-up, compared with 10.4% (58/562) of those who received a identical placebo.
“Previous studies have found that the metformin prevents the SARS-CoV-2 virus from replicating in the laboratorywhich is consistent with the predictions of our mathematical model of viral replication, so that could be what is causing the reduction in both severe and long-term COVID-19 cases seen in this trial,” said co-author David Oddbiomedical engineer from the University of Minnesota.
The investigators have acknowledged some limitations of the study, such as that individuals with a BMI less than 25 and those younger than 30 years were excluded, and therefore it is unknown whether their results could be generalized to these population groups.