A deeper dive into Prilenia's updates about Pridopidine application for market authorization

A summary of the latest webinar and Q&A session with Prilenia

On March 18th, we had a webinar with Henk Schuring, Chief Regulatory and Commercialization Officer at Prilenia, and Anne Rosser, Professor at Cardiff University, where we had the opportunity to better understand what Prilenia’s request for EMA’s (European Medicines Agency) approval of Pridopidine means for the Huntington’s Disease (HD) community. 

What do we know?

Last year, Prilenia’s clinical trial testing Pridopidine (PROOF-HD) on early stage symptomatic patients showed significant benefits and improvements on day-to-day function, cognition and motor symptoms on the group of patients who were not on neuroleptics (antipsychotics) or anti-chorea (Tetrabenazine, Austedo, etc.) medications. Nevertheless, the evaluation about the benefits of use and disuse of these drugs should always be performed by a healthcare professional.

This year, Prilenia announced that after having positive and constructive feedback from regulatory agencies, they plan to submit a Marketing Authorization Application (MAA). This means that they will present to the European Medicines Agency (EMA) all the files that contain information about the quality, efficiency and safety of the drug according to animal studies and clinical trials (actual and previous studies). 

It’s important to take into account that after the application is submitted, the review from EMA can take up to a year and, in case it is approved, it does not mean that the drug will be immediately available in every country.

Questions & Answers

Questions & Answers

Is Prilenia planning to have more studies in early stage patients, who are showing subtle symptoms but are not considered manifest?

They’re looking into it but in the early stage it’s hard to measure the advances and it may take a long time. Since there aren’t measurable symptoms in this stage, the main challenge is to identify an endpoint – an event or outcome that can be measured objectively to determine whether the intervention being studied is beneficial. 

What is the degree of impact of pridopidine in practical terms?

The degree of impact may have some variability on each patient. The key is that pridopidine slows down the loss of function. Some people don’t notice the changes, but for their surroundings the slowing of the symptoms is evident.  Other patients notice that they are able to read, cook and wear buttoned t-shirts again. 

How long have patients been treated with Pridopidine? And for how long would they have to take the drug?

The studies include patients who have been on pridopidine for up to seven years. Pridopidine is not a cure so patients would have to take it for the rest of their lives.

Once commercially available will it not make sense to make it available to pre-symptomatic patients — why will it require a new study?

In order to approve the drug being used with pre-symptomatic patients, regulatory agencies require evidence and data that includes that specific population. But the study that has led to this market approval application, PROOF-HD, evaluated the efficacy and safety of pridopidine in patients with early stage manifest Huntington’s Disease. 

I have seen that pridopidine is sold online by other companies. Why are we waiting for approval?

The pridopidine you can find online is a chemical compound that has not been designed or tested for human use. The difference between a chemical compound and a drug is that, the latter, is always designed taking into account the mechanism, frequency, doses and other important aspects that have an impact on how beneficial or harmful a chemical compound can be. Pridopidine as a molecule for human use has not been yet approved by the corresponding regulatory authorities to be used as a drug.

How likely is it that the drug would be approved?

According to the European Medicines Agency (EMA), the regulatory agency that will receive the commercialization application, about 80% of the applications get approved. But this statistic doesn’t mean that this specific drug will be approved.

What would the price of the drug be? In case many patients are able to use the drug is the production of the drug scalable?

There isn’t an established price yet. Prilenia will try to achieve sustainable access, to make it available to as many patients as possible. In terms of scalability, they already have plans in case it gets approved and since it’s a chemical component and not a biological component, scaling up the production is feasible

If this medicine is slowing the disease, is there a period of extra years for a patient like me where the disease just started?

The drug has demonstrated to slow down the loss of function that results from the disease, but not to increase life expectancy, there must be more long term data to make a strong claim such as the drug adding years to a patient’s lifetime.

How many patients took part in the study? 

PROOF-HD had 499 patients enrolled, and in both wings (drug and placebo) of the trial about half of the patients were on neuroleptics.

How long will it take from approval to commercialisation?

In case EMA approves the application, each country will have its commercialisation timeline according to their own regulatory requirements.

What lies in the future?

Even though there is still a long way to go, both Prilenia and healthcare professionals who have been involved in the trial are very optimistic about this milestone. “It’s the first time a product is going to be reviewed for this disease. Stay tuned and work with the researchers.”, says Henk Schuring. 

According to professor Anne Rosser, the studies with Pridopidine have shown the community what can be achieved with the effort of science and with the commitment of the community to take part in research. “This is important for HD and it’s a learning experience about how to jump from a trial to submission. It’s really key that all the families remain engaged in understanding the information and issues.”, she says. 

– Article written by Jarelys López