Metformin for COVID-19

Bottles of Metformin on a shelf

News from the frontline:

The COVID-OUT clinical trial findings:

  • Metformin reduced emergency room visits, hospitalization, or death by 42%
  • When taken immediately after symptoms, metformin reduced serious outcomes by over 50%
  • Ivermectin and low-dose fluvoxamine did not improve outcomes of COVID-19

The University of Minnesota recently completed the COVID-OUT clinical trial: a large rigorous study to understand if common, already available medicines (metformin, fluvoxamine or ivermectin) prevent severe COVID and long-COVID symptoms. The results were published in the New England Journal of Medicine.

From the university’s press release: “We are pleased to contribute to the body of knowledge around COVID-19 therapies in general, with treatments that are widely available,” said Carolyn Bramante, MD, principal investigator of the study and an assistant professor of internal medicine and pediatrics at the U of M Medical School. “Our trial suggests that metformin may reduce the likelihood of needing to go to the emergency room or be hospitalized for COVID-19.”

The study also reported that reduced-dose fluvoxamine, an antidepressant, and ivermectin, and anti-parasitic, alone or in combination with metformin, did not improve outcomes for individuals infected with COVID.

Additional facts about the study:

  • 1323 individuals participated in the study.
  • The metformin results were a secondary outcome: the primary outcome included low oxygen, but none of the medications in the trial prevented the primary outcome.
  • Only adults with a BMI (body mass index) greater than or equal to 25kg/m2 were enrolled.
  • Pregnant women were included in the metformin group.
  • The majority of participants were vaccinated, and metformin was effective for both vaccinated and unvaccinated individuals.
  • Fluvoxamine doses were a third to half as much as used in previous studies in an attempt to avoid side effects. This may explain why previous positive results were not found in this study.

How a small foundation made a difference

With COVID-19 infection rates soaring around the world, the Parsemus Foundation’s founder and trustee Elaine Lissner sought a way for her small private foundation to help. She identified an unmet need for research to determine if inexpensive existing medications or vaccines may provide treatment options. The Parsemus Foundation funded three COVID-19 clinical trials.

When it was clear that enrolling individuals in COVID-19 clinical trials was challenging, the Parsemus Foundation’s small team then started a major initiative to directly support enrollment in the next two studies. We provided online advertising and a user-friendly communications interface to boost enrollment for the trials. For over a year, almost all foundation resources were aimed at meeting enrollment requirements for the trials with the goal of finding promising existing medications to fight COVID-19.

The COVID-OUT clinical trial reached its enrollment goals, and reported findings that may improve treatment options for COVID-19.

“It was a steep learning curve to set up advertising campaigns and enrollment methods that helped participants enroll in the trials,” noted executive director Linda Brent. “We are proud that our efforts have resulted in critical data about the role of metformin for treatment of COVID-19. It proves the impact that a small foundation can have on finding solutions to global problems.”

Senior patient and doctor, wearing medical face masks, communicating in hospital office.


Metformin lowers blood sugar and inflammation by activating an enzyme called AMPK. This activity also appears to reduce angiotensin-converting enzyme 2 (or ACE2), which serves as a gateway for COVID-19 to enter and infect cells. Thus, the way metformin works to control blood sugar might also help to control coronavirus infection (see this article in Everyday Health).

A number of inexpensive, safe, existing medications have been studied as possible treatments for COVID infection. With limited profit potential and lack of research funding, it has taken time for the required clinical studies to be completed. 

Visit your doctor to learn about treatment options. You can bring information like that included in this website to discuss metformin with your healthcare provider.

Strong observational and randomized clinical trial data exists to support the use of metformin as a treatment for COVID. It is up to regulatory bodies (such as the US FDA) whether they will officially add metformin to approved COVID treatments.

See Additional Resources below.

Human Health News

We’re sorry, you are not eligible for the nationwide COVID-OUT or ACTIV-6 studies, but you may be eligible for other federal trials:

And if you don’t find a match there, this slightly more complex clinical trials finder includes studies sponsored by companies as well:

Trials Today