Trial Participation FAQs

Click here to download a PDF with all the Trial Participation FAQs

The drugs that have been chosen are generally very safe. There are rare serious side-effects in a few people which will be fully discussed with all potential participants.

People with MS who want to join Octopus will be asked to first sign a consent form and attend a hospital visit where the clinical team will do some tests and examinations to assess whether they can take part. These assessments include:

  • A Magnetic Resonance Imaging (MRI) scan
  • Blood and urine samples 
  • Medical history and physical examination
  • Neurological assessments (measuring strength, coordination, arm and hand function, vision, etc)
  • Wellbeing and health questionnaires (measuring pain, memory, fatigue, etc)

If the tests show that the person can take part, they will be asked to confirm if they wish to join the trial before formally entering the trial and being allocated to a treatment. 

Octopus participants in Analysis Stage 1 will do

  • Three magnetic resonance imaging (MRI) scans 

  • Tests such as blood and urine tests, walking and sight tests, Expanded Disability Status Score (EDSS), tests of hand and arm function and thinking

  • Questionnaires about different areas of health and wellbeing including about fatigue, pain and quality of life

Participants in Analysis Stage 2 will not have the MRI scans but will do the tests and questionnaires.

The short answer is up to 5 years.

However,  if you join the first part of the trial (called Analysis stage 1), then approximately 3.5 years into the trial there will be an analysis to check if the treatments are showing benefit to the participants.

    • If it shows benefit, the treatment will continue.
    • If they do not show benefit, those participants taking the treatment will stop.
    • For those participants who stop treatment, if they would like to, after 6 month you can be screened again and re-join the trial if you are eligible to receive other treatments in Octopus.
  • The first 3 visits are roughly monthly. These are the screening visit, the randomisation visit (also called week 0), and the first follow up visit (called week 4)
  • After that, in person visits will be every 6 months
  • There will be a telephone call in between (every 3 months) for participants on trial treatment

This will vary at each visit. For a list of what will take place at each visit can be found on the visit information leaflet.  Some examples of the assessments are:

  • physical assessments to assess your neurological system including strength, co-ordination, walking and tests of arm function such as the 9-Holed peg test and 25-foot walk
  • a general physical examination
  • a check of your medical history
  • written (or completed electronically) some assessments asking about pain, fatigue, and your quality of life
  • some blood and urine tests
  • 4 Magnetic Resonance Imaging (MRI) scans over 2 years


All people with MS who are screened for the trial will have one MRI scan at screening, before starting the trial. Those go on to enter the trial will have three more: at 6 months, 18 months, and 24 months - all on the same scanner.

We won’t know if these drugs slow disability progression until 2028 at the earliest. This is because Octopus is combining what would normally be two separate trials into one.  

At visits, participants will be seen by different members of the hospital study team including research nurses, doctors responsible for overseeing the treatment, and other doctors responsible for carrying out neurological assessments. There will also be an admin support team, who will help book appointments either at the visit or by telephone.

Yes. Please speak to your hospital study team to find out how to claim these costs.

As part of the Octopus study design, if a treatment does not appear to be of benefit at the end of Analysis Stage 1, it may be stopped. If this happens participants who are on that treatment arm will have a final visit with their study doctor, who will arrange for their standard treatment to continue outside the study.

These participants, if they would like to and are still suitable for the study, may be offered the opportunity to join the study again later. This is possible after a suitable period of time (probably around 6 months). If this is the case for you, your study doctor will discuss this with you.

Yes. The study is completely voluntary, and any participant can withdraw from the study at any point with no explanation given, and no change to their standard of care.

If you decide to stop taking your study treatment, we may ask for you to still attend hospital visits every 6 months so we can continue collecting information about you for up to 5 years. This is important, because it helps us to ensure that the results of the study are reliable. Again, there is no obligation to do this.

Both metformin and alpha-lipoic acid are regarded as being safe medications. With regards to their potential effects during fasting, there is less certainty however they are likely still safe.

Metformin is commonly prescribed for patients with diabetes, and it is extremely rare to develop hypoglycaemia (low blood sugar levels) from metformin use alone.

Given this, it is generally considered safe in the absence of other conditions/medications that might exacerbate the risk of low blood sugars, to fast while on metformin.

Alpha-lipoic acid seems to be similarly safe, with only very limited evidence of it potentially influencing blood sugar levels, and primarily in people with diabetes taking insulin or other antidiabetic drugs.

See the questions What does hypoglycaemia (low blood sugar) feel like? and What do I do if I feel like I might be having episodes of low blood sugar? for further information

The symptoms of hypoglycaemia can vary from person to person, but the most common early signs include:

  • Sudden tiredness and difficulty concentrating
  • Sweating heavily
  • Dizziness, trembling, or shaking
  • Feeling anxious or irritable
  • Feeling hungry
  • Tingling lips
  • Going pale
  • A fast, pounding, or racing heartbeat (palpitations)

If you’re feeling suddenly unwell with the above, you should consume a sugary drink/food item and seek the advice of your GP or attend A&E for an assessment.

If you have similar symptoms while fasting and taking the trial drug, but are not feeling that way at the time, you should contact your trial team for further advice.

Yes. Octopus medications do not contain any animal products in the active ingredients or the capsules. 

As all other medicines, animal testing will have been involved in the production of these medications at some point in the development process, but there are no animal-derived ingredients. Further information regarding veganism and medications is available through the Vegan Society.

Octopus is funded by the MS Society