EPI-743, also known as Vincerinone, is a tablet taken by mouth, developed by a US Company called Edison Pharmaceuticals.
It is a type of CoEnzyme Q10, which is found naturally in our cells and is essential for proper energy production within the mitochondria.
How does it work?
EPI-743 works like CoEnzyme Q10, as anti-oxidant, carrying electrons along the energy chain to make energy in the form of ATP.
EPI-743 is reported to be more potent and more highly absorbed than naturally occurring CoEnzyme Q10.
What is it supposed to do?
It is supposed to increase the amount of energy the mitochondria can produce which might reduce some of the symptoms of Mitochondrial Disease.
Is it a cure?
Unfortunately no, EPI-743 cannot correct the underlying genetic defect, which causes the disease.
What types of Mitochondrial Disease could it treat?
It is currently being trialed in Leigh Syndrome and MELAS but if successful, it could be used to treat any inherited mitochondrial respiratory-chain disease.
Have there been any trials of EPI-743?
Initially this drug was trialed on terminally ill children in the USA/Europe on compassionate grounds. The assumption was that that these children were expected to die and there was no risk in trying something new.
Quite surprisingly many of these children seemed to show improvement, which was backed up with clinical observations and improvement on their brain scans.
Edison therefore decided to expand this trial to 10 more children in the USA with genetically confirmed Leigh Syndrome (all with different genetic causes) and they monitored a variety of different aspects of their health over 6 months.
Results were published in 2012 and showed that over the duration of the trial, all 10 patients exhibited reversal of disease progression regardless of genetic defect or disease severity, and none showed obvious adverse reaction to the drug.
How do the researchers know that EPI-743 was the reason for improvement?
This is very hard to prove, because the natural course of mitochondrial diseases can be up and down, so it can be hard to assess whether the introduction of a drug at a specific point is the cause of the improvement or decline.
In addition, all the children selected (and their families) knew they were taking the drug and why, so they could have had pre-conceived ideas about what it would do.
This phenomenon (known as the placebo effect) can happen where a person takes a medicine that he or she perceives will help, although it has no proven therapeutic effect for the condition. They then believe that the medicine is working and they see improvement, which may or may not really be there.
As a result, the medical community called for Edison to undertake further trials.
Further Trials - still awaiting published results
Further trials took place at several centers in the USA looking at the effects and safety of EPI-743 in 35 children with a genetic diagnosis of Leigh Syndrome over a 6 month period.
This study involved the use of an active and inactive drug, used in two groups of patients side by side so that the patients didn’t know which one they were taking. This is known as a ‘double-blind placebo-controlled trial’ and gives the best quality evidence. The groups were then swapped over after 6 months, so each child received the active drug for half of the trial. Disease progression assessments were undertaken throughout.
This trial was completed in 2015 but as yet, no results have been published, meaning that detailed information on the outcomes of the study are not currently available. Edison themselves issued a press release in June 2016 which gave an indication that hospital admissions were reduced over the period of the trial, but this data remains unpublished and has not been evaluated by other experts working in the field (known as ‘peer-review’).
We are also unable to find any published results from similar trials undertaken in Japan and Europe.
Further Trials - ongoing
Following on from this study, there is now a longer term evaluation of EPI-743 ongoing in children with Leigh Syndrome which is currently enrolling participants by invitation only. The aim of the study is to monitor the long-term effects and safety of EPI-743 in children who complete the initial 6-month placebo-controlled trial, with all children in the extended phase of the trial taking EPI-743 for up to 3 years.
This study is due to end in April 2017 and as such, no results have yet been published.
Will we get EPI-743 in the UK?
Currently there is no UK licence for EPI-743 and as far as we are aware, the only recipients of this drug are those enrolled on clinical trials.
Whilst we really hope that this drug is effective, it is possible that the published results from the trial may show that EPI-743 has no significant benefit, or could even be harmful for patients.
Should EPI-743 prove to be of benefit, then we would anticipate the NHS taking steps to ensure this drug is available to UK patients.
Are there any medical papers on these trials?
Molecular Genetics and Metabolism – Jan 2012
Molecular Genetics and Metabolism – Nov 2012