BETHESDA, MD — New research into the mechanisms underlying myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and long COVID is aimed at identifying potential approaches to treatment of the two overlapping illnesses.
According to a new data brief from the National Center for Health Statistics, in 2021-2022, 1.3% of US adults had ME/CFS, a complex, multisystem illness characterized by activity-limiting fatigue, worsening of symptoms after exertion, unrefreshing sleep, and other symptoms.
A 2-day conference, Advancing ME/CFS Research: Identifying Targets for Potential Intervention and Learning from Long COVID, was held in December 12-13 on the main campus of the US National Institutes of Health (NIH) and was livestreamed. The last such meeting, also featuring results from NIH-funded research, was held in April 2019.
“Things have changed since 2019 ... The idea of this meeting is to try and identify pathways that will be treatable and druggable and really make an impact for patients based on the things that we’ve learned over the last number of years and including, fortunately or unfortunately, the huge number of people who are suffering from long COVID, where the symptoms overlap so much with those who have been suffering for a long time with ME/CFS,” said Conference Chair Joe Breen, PhD, of the National Institute of Allergy and Infectious Diseases.
As in 2019, the meeting was preceded by a day of research presentations from young investigators, some of whom also presented their findings at the main meeting. New this year were four “lived experience” speakers who described their physical, emotional, and financial struggles with ME/CFS or long COVID. Two of them presented virtually because they were too ill to travel.
Social worker and patient advocate Terri Wilder of Minneapolis, Minnesota, reported some feedback she received on social media after she asked people with ME/CFS about their priorities for the research and clinical communities.
Among the top responses were the need to recognize and study the phenomenon of “post-exertional malaise” and to stop recommending exercise for people with these illnesses, to accelerate research to find effective treatments, and to put an end to stigma around the condition. “People don’t believe us when we tell them we’re sick, people make fun of us, misperceptions persist,” Wilder said.
One person commented, “[Clinicians] shouldn’t be afraid to try off-label meds with us if needed. There may be some secondary effects, but they are better options than us taking our own lives because we can’t stand the suffering.”
Research areas covered at the conference included immunology, virology, metabolism, gene regulation, and neurology of both ME/CFS and long COVID, as well as the latest findings regarding the overlap between the two conditions.
Oxidative Stress in Both ME/CFS and Long COVID: A Role for Metformin?
Mark M. Davis, PhD, professor and director of the Institute for Immunity, Transplantation, and Infection at Stanford University, Palo Alto, California, summarized published data suggesting that oxidative stress is a shared characteristic of both ME/CFS and long COVID. Most cellular reactive oxygen species (ROS) are produced in the cell’s mitochondria, and T-cell activation is ROS-dependent.
Women in particular with ME/CFS show high ROS levels with consistent T-cell hyperproliferation, “which can be suppressed with specific drugs such as metformin. This raises the prospect of optimizing drug treatment and drug discovery with a simple in vitro assay of the effects on a patient’s lymphocytes,” Dr. Davis said. He also cited a study suggesting that metformin may help prevent long COVID.
Asked to comment on that, longtime ME/CFS researcher Anthony L. Komaroff, MD, of Harvard University, Cambridge, Massachusetts, cautioned that although metformin is used safely by millions of people with type 2 diabetes worldwide, it’s possible that some people with ME/CFS may be more likely to experience its known adverse effects such as lactic acidosis.
To repurpose metformin or any other already-marketed drugs for ME/CFS and/or long COVID, Dr. Komaroff said, “We should entertain treatment trials.” However, as he and many others lamented at the conference, funding for off-patent drugs often isn’t forthcoming.