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Long COVID clinical trial

Many thanks for your interest in our study. 

The purpose of this study is to learn about the effects of the study medicine, AXA1125, on your symptoms of fatigue, and to see how safe the study medicine is for patients with fatigue-predominant PASC. AXA1125 is a study medicine because it has not been approved by the Medicines and Healthcare products Regulatory Agency (MHRA), the health authority that approves new medicine being prescribed for use in the United Kingdom.

Approximately 40 participants, aged between 18 and less than 65 years of age, will take part in this study at Oxford University Hospitals NHS Foundation Trust in the United Kingdom. Participation in this study will last approximately 9 weeks and include 3 study visits to the study site and 2 phone calls.

If you're interested in volunteering for this study, please read the information below, and email us at

Study medications

This study medicine, AXA1125, is made up of a mixture of 6 different amino acids. Amino acids are small molecules that make up the building blocks of proteins in the body. Amino acids are a normal part of the human diet, can be in some dietary supplements, and some are produced naturally by the body. AXA1125 does not include any known allergens e.g lactose or animal products e.g. gelatin in the IMP or the placebo.

It is thought that supplementation of amino acids may help to improve symptoms of fatigue after COVID infection via the modification of various cellular processes, including the way your body processes energy.

Researchers use a placebo (no active ingredients) to see if a study medicine works better or is safer than taking the placebo. The placebo looks and tastes like the study medicine but does not contain any active ingredients (amino acids).

The study medication or placebo will be provided as a powder packaged in sachets. For each dose, three sachets will be mixed with water to make an orange-flavored drink. You will drink the study product two times daily with or without food for 4 weeks.

You will be randomly assigned by chance, like the flip of a coin, to receive either AXA1125, or placebo. You will have a 1 in 2 chance of receiving AXA1125 and a 1 in 2 chance of receiving placebo. This is a double-blind study, which means neither you nor the study doctor will know to which of these study medicine groups you are assigned.

What will happen during the research study?

There are 3 stages to this study:

  • A Screening Period (up to 4 weeks)
  • A Treatment Period (4 weeks)
  • A Follow-Up period (1 week).

If you agree to participate in this study, the research staff will perform tests and assessments to determine if you are eligible to receive the study drug. The assessments for this study may include:

  • A physical examination and vital signs
  • Blood and urine tests (including test for drug use)
  • An alcohol breath test
  • An Echocardiogram (Echo)
  • Completion of a questionnaire about your fatigue;
  • Magnetic Resonance Spectroscopy imaging
  • A 6 Minute Walk Test

We will provide further detailed information to all study volunteers, and you will also have the chance to ask any questions before participating.