EMA has agreed to evaluate the MAA for pridopidine for the treatment of Huntington's disease

Last September 3, Prilenia Therapeutics announced that EMA has formally agreed to start the evaluation process of the Marketing Authorization Application in Europe for pridopidine (45 mg orally twice daily ) for the treatment of adult patients with clinical manifestations of Huntington's disease. The application was submitted at the end of July.

The MAA evaluation typically takes 12 to 14 months, but may involve a longer waiting period. 

In the meantime, the company informs that it has also begun a dialogue with the FDA on a potential path forward for pridopidine in the United States and that it will consider doing the same in other Countries once the regulatory review process is concluded in Europe.

If EMA grants the Marketing Authorization, a further step will still be necessary at individual Country levels.

In Italy the subsequent evaluation will have to be carried out by AIFA with which the industry will also have to negotiate the reimbursement price. This step will also take additional time.

Pridopidine is a sigma-1 receptor (S1R) agonist with a very well documented safety profile.

It is a molecule for oral use, which has shown a high safety profile, despite not having achieved, in the recent phase three PROOF-HD trial, its primary endpoint: the improvement of disease progression, measured as the effect on autonomy through a functional capacity scale called Total Function Capacity (TFC). 

However, subsequent data analysis have shown benefits in some of the patients, those in early disease stages not treated with some neuroleptic drugs (especially tetrabenazine/xenazine).

This means that, if the EMA approved the request for the marketing of pridopidine, there would not be "the drug that cures the disease" available, nor a drug available to anyone with a Huntington's disease mutation in their DNA, but only to patients 1) adults and 2) with clinical diagnosis and manifestations.

In these cases, pridopidine could represent a well-tolerated pharmacological resource capable of mitigating, in some cases, the disease.

This would be a step forward compared to the current situation and, certainly, would represent a sign of hope for the community of families affected by Huntington's disease. It should, however, be underlined that the greatest benefit for patients remains the good clinical practice by health care professionals, who should personalize the treatment of symptoms through the use of drugs suited to each individual's clinical conditions. 

The fact that an experimental drug works less well in the presence of drugs that are sometimes abused in clinical practice represents the most striking example of "primum do no harm".

Pridopidine is currently administered - as an experimental drug not (yet) on the market - as part of a compassionate use program which will be interrupted at the end of the approval process.