A new analysis from the ACTIV-6 clinical trial confirms that taking the common diabetes drug metformin during an acute COVID-19 infection can cut the risk of developing long COVID by roughly 50 percent. The findings, reported by Medical Xpress, provide important confirmation of earlier trial results and suggest that a widely available, inexpensive medication with a long safety record may help prevent a condition that affects millions.

Key takeaways

  • Metformin started during acute COVID-19 reduced the risk of clinician-diagnosed long COVID by about 50 percent.
  • The results come from the ACTIV-6 trial, a large randomized study that confirms earlier findings.
  • Metformin is a cheap, widely available drug with a well-established safety profile.
  • The medication was most effective when taken soon after symptoms began.

What the study found

The ACTIV-6 trial was designed to test several repurposed medications for COVID-19. In this latest analysis, researchers looked specifically at metformin, a drug typically used to treat type 2 diabetes. Participants who took metformin within a few days of developing COVID-19 symptoms were significantly less likely to later receive a diagnosis of long COVID from their doctor.

The 50 percent reduction in risk is a substantial effect, especially when compared to other interventions tested during the pandemic. The study authors noted that the benefit was consistent across different age groups, sexes, and vaccination statuses. Importantly, the drug appeared to work best when started early, within the first few days of symptom onset.

Why this matters

Long COVID, also known as post-acute sequelae of SARS-CoV-2 infection, remains a major public health challenge. Symptoms can include fatigue, brain fog, shortness of breath, and joint pain, and they can last for months or years. Currently, there are no approved treatments specifically for preventing long COVID.

Metformin is an attractive candidate because it is already widely used, costs pennies per dose, and has a well-known safety profile. Unlike some other COVID-19 treatments, it does not require special storage or administration, making it accessible in low-resource settings. The new results suggest it could be a practical tool for reducing the burden of long COVID.

How the trial worked

The ACTIV-6 trial was a large, randomized, placebo-controlled study conducted across multiple sites in the United States. Participants were adults with confirmed COVID-19 who were not hospitalized. They were randomly assigned to receive either metformin or a placebo, and they were followed for several months to track outcomes, including the development of long COVID.

The diagnosis of long COVID was made by clinicians based on symptoms and medical history, not just self-report. This adds credibility to the findings, as clinician-diagnosed cases are generally more reliable than patient-reported symptoms alone. The study was funded by the National Institutes of Health as part of its rapid-response research program.

Limitations and next steps

While the results are promising, the study has limitations. The trial was conducted during a period when the Omicron variant was dominant, so it is unclear whether the same benefit would apply to other variants. Additionally, the study did not test metformin in combination with other drugs, such as antivirals or monoclonal antibodies.

Researchers say more work is needed to understand exactly how metformin reduces long COVID risk. It may work by lowering viral load, reducing inflammation, or affecting the immune response. Future studies could also explore whether the drug is effective in people who are already experiencing long COVID symptoms.

Frequently Asked Questions

Who should consider taking metformin for COVID-19?

Based on the study results, adults who test positive for COVID-19 and are at risk for long COVID may benefit from taking metformin early in their illness. However, individuals should always consult a healthcare provider before starting any new medication, as metformin can cause side effects and may not be safe for everyone, particularly those with kidney or liver problems.

Is metformin a substitute for vaccination or other treatments?

No. Metformin is not a replacement for COVID-19 vaccines, which remain the best way to prevent severe illness and death. It is also not a substitute for antiviral drugs like Paxlovid, which are recommended for high-risk individuals. Metformin may be used as an additional preventive measure, but it should not replace standard care.

How long should metformin be taken after a COVID-19 diagnosis?

In the ACTIV-6 trial, participants took metformin for 14 days starting within a few days of symptom onset. The exact duration that provides the best protection is still being studied. Patients should follow their doctor’s advice regarding dosing and duration, as individual factors may influence the optimal regimen.

This is an original report by Vital Signs Today, informed by reporting from Medical Xpress. Read the original source.

This article is for information only and is not medical advice. See our Medical Disclaimer.