CHICAGO-
Lauren Nichols, a 34-year-old logistics expert for the US Department of Transportation in Boston, has suffered from impaired thinking and concentration, fatigue, seizures, headaches and pain since her COVID-19 infection in the spring of 2020.
Last June, her doctor suggested low doses of naltrexone, a generic drug typically used to treat alcohol and opioid addiction.
After more than two years of living in “a thick, hazy cloud,” she said, “I can actually think clearly.”
Researchers looking for long COVID cures are eager to find out if the drug can provide similar benefits to millions of people suffering from pain, fatigue and brain fog months after coronavirus infection.
The drug has been used with some success to treat a similar complex post-infectious syndrome marked by cognitive deficits and overwhelming fatigue called myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).
Building on its use in ME/CFS and a handful of long-term COVID pilot studies, there are now at least four clinical trials planned to test naltrexone in hundreds of patients with long COVID. , according to a Reuters review of Clinicaltrials.gov and interviews with 12 ME/CFS and long COVID researchers.
It is also on the short list of treatments to be tested under the US National Institutes of Health’s billion-dollar RECOVER initiative, which aims to uncover underlying causes and find treatments for along COVID, trial advisers told Reuters.
Unlike treatments aimed at treating specific symptoms caused by COVID damage to organs, such as the lungs, low-dose naltrexone (LDN) can reverse some of the underlying symptoms of the condition, they said.
Naltrexone has anti-inflammatory properties and has been used in low doses for years to treat conditions such as fibromyalgia, Crohn’s disease and multiple sclerosis, said Dr. Jarred Younger, director of the Neuroinflammation Laboratory. , Pain and Fatigue from the University of Alabama. in Birmingham.
At 50 milligrams – 10 times the low dose – naltrexone is approved to treat opioid and alcohol addiction. Several generic manufacturers sell 50mg pills, but low-dose naltrexone must be purchased from a compounding pharmacy.
Younger, author of a scientific review of the drug as a new anti-inflammatory, submitted a grant application in September to study LDN for long COVID. “It should be at the top of everyone’s list for clinical trials,” he said.
Still, the drug is unlikely to help all patients with long COVID, a collection of some 200 symptoms ranging from pain and heart palpitations to insomnia and cognitive impairment. A ME/CFS study of 218 patients found that 74% had improvements in sleep, pain reduction and neurological impairment.
“It’s not a panacea,” said Jaime Seltzer, a Stanford researcher and science outreach manager for the advocacy group MEAction. “These people were not cured, but they were helped.”
Dr Jack Lambert, an infectious disease expert at University College Dublin School of Medicine, had used LDN to treat pain and fatigue associated with chronic Lyme disease.
During the pandemic, Lambert recommended LDN to colleagues treating patients with persistent symptoms after bouts of COVID.
It worked so well that he conducted a pilot study with 38 long-term COVID patients. They reported improvements in energy, pain, concentration, insomnia and overall recovery from COVID-19 after two months, according to results released in July.
Lambert, who is planning a larger trial to confirm these results, said he believes LDN may reverse the damage of the disease rather than mask its symptoms.
Other planned LDN trials include one from the University of British Columbia in Vancouver and a pilot study from Ann Arbor, Michigan-based startup AgelessRx. This study of 36 volunteers should have results by the end of the year, said the company’s co-founder, Sajad Zalzala.
Scientists are still working to explain how LDN works.
Experiments by Dr Sonya Marshall-Gradisnik from the National Center for Neuroimmunology and Emerging Diseases in Australia suggest that ME/CFS and long-lasting COVID symptoms result from a significant reduction in natural killer cell function in the immune system. In lab experiments, LDN may have helped restore their normal function, a theory that has yet to be confirmed.
Others believe infections trigger central nervous system immune cells called microglia to produce cytokines, inflammatory molecules that cause fatigue and other symptoms associated with ME/CFS and long COVID. Younger thinks that naltrexone calms these hypersensitized immune cells.
Dr Zach Porterfield, a virologist at the University of Kentucky who co-chairs a RECOVER task force examining commonalities with other post-infectious syndromes, said he had recommended that LDN be included in treatment trials for RECOVER.
Other therapies being studied, sources said, were antivirals, such as Pfizer Inc’s PFE.N Paxlovid, blood-thinning agents, steroids and nutritional supplements. RECOVER officials said they received dozens of proposals and could not comment on which drugs will be tested until the trials are finalized.
Dr. Hector Bonilla, co-director of the Stanford Post-Acute COVID-19 Clinic and RECOVER advisor, has used LDN in 500 ME/CFS patients, about half of whom report benefit.
He studied LDN in 18 patients with long-term COVID, including 11 showing improvements, and said he thinks larger formal trials could determine if LDN offers a real benefit.
Nichols, a RECOVER patient advisor, was “ecstatic” when she learned that LDN was being considered for government-funded trials.
Although LDN hasn’t resolved all of his COVID-related issues, Nichols can now work all day without breaks and have a social life at home.
“It made me feel like a human again.”
(Reporting by Julie Steenhuysen in Chicago; Editing by Caroline Humer and Bill Berkrot)