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© Martin Phelps

Researchers at the Oxford University Radcliffe Department of Medicine have now begun screening patient volunteers for a potential drug treatment for long COVID. The treatment is produced by the US-based biotechnology company Axcella Therapeutics (Nasdaq: AXLA), and researchers will test whether it can reduce the severe fatigue from activity experienced by many patients with Long COVID.

The new trial, taking place at the John Radcliffe Hospital, will test the safety as well as the potential efficacy of Axcella’s AXA1125 treatment, which patients will take orally. Data from this trial is expected to be reported in mid-2022.

Lead researcher Dr. Betty Raman, British Heart Foundation Oxford Centre of Research Excellence Clinical Transition Intermediate Fellow, said: ‘There already has been a tremendous amount of interest in participating in this trial among patients suffering from Long Covid fatigue. This is not surprising given the sheer number of patients impacted by this syndrome, the life-changing symptoms that they are experiencing and the complete absence of treatment options today.’

Dr. Raman, who also leads the C-MORE study which quantifies the organ damage and other longer term effects of COVID, said: ‘We are keen to evaluate AXA1125’s impact on the mitochondria and muscle function and its potential to improve functional outcomes for patients who experience profound fatigue.’

Mitochondria act as the battery for cells, serving as both the source of energy generation and storage. Many long COVID patients report they are unable to exert themselves without feeling severe fatigue. One hypothesis for these symptoms is that SARS-CoV-2 infection can damage the mitochondria and interfere with its ability to function normally, even long after the virus itself has been cleared.

Dr. Raman and her colleagues will be using sophisticated MRI scanners to track the dynamics of a chemical called phosphocreatine, a marker for how well mitochondria are functioning, before and after gentle exercise. They will also track blood levels of lactate – another measure of mitochondrial health – as well as how far patients can walk on the ground over six minutes.

Dr Mark Cassar, cardiologist and study co-investigator said "The large number of people expressing interest in our study highlights the devastating impact that long COVID is having on peoples’ lives. By means of this trial, we are one step closer towards a treatment, or potentially a cure, for the persistent fatigue experienced by patients following infection with COVID-19."

The researchers will randomly allocate 40 volunteers with long COVID-related fatigue symptoms to receive either daily doses of AXA1125 or a ‘dummy’ placebo, tracking how mitochondrial function, exercise tolerance and fatigue levels change after 28 days of the treatment, and how the two groups of patients differ. Neither the clinicians tracking the patients’ progress nor the patients themselves will know who has received the drug or placebo, to avoid biasing the results of the study. The research team will also be monitoring the safety of the treatment and any unexpected side-effects.

Dr. Alison Schecter, President of R&D at Axcella which is funding the study, said: ‘There is mounting evidence suggesting that infection with the COVID-19 virus can impair the mitochondria’s ability to act as the ‘powerhouse’ of the cell.

‘Axcella’s preclinical and clinical findings to date demonstrate that AXA1125 holds the potential to improve multiple aspects of mitochondrial biology, including increasing energetics and reducing inflammation. This provides hope that we can make a real difference for tens of millions of patients suffering from this debilitating condition.’

If you’re interested in participating, please email or visit

Study participants must be aged 18 to 65, must have had symptoms of COVID-19 and a positive PCR test or antibody test at least 12 weeks before screening to take part in the study.