MedDay is committed to developing new treatments for nervous system disorders. In order to gain Regulatory Agency approval for new medications to advance patient care, successful clinical trials are required.


A clinical trial is a research study to evaluate new potential treatments in people. During a clinical trial, information is collected to determine if a study drug is safe and effective, as well as to evaluate the risks and benefits of the study drug.


Firstly, pre-clinical testing of the active substance is carried out in the laboratory and in animals to evaluate the safety and efficacy of a drug before it is given to humans.

The drug is developed as a pharmaceutical formulation with the aim to master the delivery of the active substance to its target. All the components of the drug must be perfectly characterized and of high purity.

An IND (Investigational New Drug) application is then submitted to the regulatory agency (e.g. FDA or EMA) so that they can evaluate the drug for safety to assure that human patients will not be subjected to an unreasonable risk.

Clinical trials are conducted in 4 phases and each phase has a different purpose to help answer different questions:

  • Phase I: this type of study includes a small number of healthy volunteers and is used to determine if a drug is safe. These studies allow to define the maximal tolerated dose.
  • Phase IIA: similar to a Phase I study, a Phase IIA study also measures safety however, only patients who have the disease in which the drug is targeting are included. These studies aim to detect if the drug might be active on the human disease.
  • Phase IIB: a larger number of patients who have the targeted disease are included in Phase IIB studies, which measure how well the drug works (efficacy) in addition to safety. These studies allow to determine the best dose to test in future larger studies.
  • Phase III: a Phase III study is used to confirm efficacy seen in earlier stage trials. If positive results are achieved, a biotech or pharma company may apply for approval to market the drug with the appropriate drug regulation organization, such as the FDA in the US or the EMA in Europe.

After these phases have been completed, a New Drug Application (NDA) is submitted to the regulatory agency (e.g. FDA or EMA). The NDA contains all data gathered about the safety and effectiveness of the study drug from the above studies. The regulatory agency reviews the data and, if approved, the new treatment can be marketed and distributed to the public.

  • Phase IV: post marketing studies are performed after regulatory agency approval to collect additional information including the drug's risks, benefits, and optimal use in a broader patient population. For example, a Registry would collect medical information on the disease population, whether they are taking the drug or not.

For more information about clinical trials in general, please visit


MedDay’s lead candidate, MD1003, for the treatment of primary and secondary progressive multiple sclerosis, has been investigated in two Phase III clinical trials of which the extension phases have been prolonged.

In April 2016, the full study results from the MS-SPI and MS-ON trials, including extension data, were presented at the American Academy of Neurology Annual Meeting (AAN). For more information on the results, click here.

The MS-SPI results were published online on 1 September 2016 in the Multiple Sclerosis Journal and can be accessed online here.

MedDay has begun a large-scale clinical trial, called SPI2, of which the primary objective is to confirm the efficacy of MD1003 in patients with progressive multiple sclerosis. The clinical trial plans to enrol a total of 600 patients at approximately 65 study centers in the US and Europe. For more information, please visit

MD1003 is also being investigated in a Phase IIb/III clinical trial in the adult form of X-linked adrenoleukodystrophy. This clinical trial is funded by the European Leukodystrophy Association (ELA) and involves four reference centres in France, Germany and Spain.

Detailed information about MedDay's clinical trials is posted in clinical trial databases in accordance with industry guidelines. To learn about MedDay's ongoing clinical trials visit and

In addition, a summary of our product information can be found on our Research and Development page.


Whilst MedDay’s clinical trials have used high doses of biotin, it is very important that it is understood that MD1003 is still an investigational medicinal product containing a pharmaceutical-grade biotin and other components which ensure the delivery of a controlled dose of the active ingredient. Self-prescription of high doses of pure biotin as bulk without medical supervision is not advised.

MedDay strongly advises against purchasing biotin from unauthorised suppliers for the treatment of MS, as the product may be mislabelled and could contain harmful substances that may result in adverse events for patients (see FDA voluntary recall, March 2016). 

MedDay is currently collecting the safety data from its clinical trials where some serious adverse effects occurred. Studies in animals have shown serious toxicity in certain species as well as teratogenicity (malformations of foetuses). High doses of biotin intake as bulk may not be safe and may be toxic.

If you are participating in a MedDay clinical trial and would like to contact someone regarding the trial, or if you need to report a problem with the study drug or side effect, please contact your study doctor as soon as possible.

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