EU/3/14/1260 - orphan designation for treatment of Charcot-Marie-Tooth disease type 1A

(RS)-Bacoflen

naltrexone hydrochloride

D-sorbitol

Overview

On 26 March 2014, orphan designation (EU/3/14/1260) was granted by the European Commission to Pharnext SAS, France, for fixed-dose combination of (R-S) baclofen, naltrexone hydrochloride and D-sorbitol for the treatment of Charcot-Marie-Tooth disease type 1A.

In May 2016, Pharnext SAS changed name to Pharnext SA.

The sponsor's address was updated in July 2021.

What is Charcot-Marie-Tooth disease type 1A?

Charcot-Marie-Tooth disease (CMT) is a group of inherited disorders of the nervous system. The symptoms include muscle weakness, tremor and sensory loss (identifiable as numbness, tingling, burning sensation), and usually first appear in the first or second decade of life.

CMT is classified in 5 groups and one of them, CMT1, is by far the most common form of the disease. Approximately 70%-80% of CMT1 patients have the type called CMT1A, which is caused by an extra copy of the gene responsible for producing the protein PMP22. This protein is a component of myelin (the protective sheath around nerves). Patients with CMT1A produce too much PMP22, and this causes the structure and function of the myelin sheath to be abnormal and leads to problems in the transmission of nerve signals.

CMT1A is a long-term debilitating disease because the progressive deterioration of nerves leads to disability and reduced quality of life.

What is the estimated number of patients affected by the condition?

At the time of designation, CMT1A affected approximately 1.4 in 10,000 people in the European Union (EU). This was equivalent to a total of around 72,000 people*, and is below the ceiling for orphan designation, which is 5 people in 10,000. This is based on the information provided by the sponsor and the knowledge of the Committee for Orphan Medicinal Products (COMP).

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*Disclaimer: For the purpose of the designation, the number of patients affected by the condition is estimated and assessed on the basis of data from the European Union (EU 28), Norway, Iceland and Liechtenstein. This represents a population of 511,100,000 (Eurostat 2014).

What treatments are available?

At the time of designation, no satisfactory methods were authorised in the EU for the treatment of CMT1A. Supportive treatments were available such as pain medications, physical therapy and corrective surgery.

How is this medicine expected to work?

This medicine consists of a low-dose combination of three substances: (R-S) baclofen, naltrexone hydrochloride and D-sorbitol, which are thought to act in different ways to limit the production of PMP22 in patients with CMT1A. The combined actions of the three substances are expected to help improve the function of the myelin sheath, improving signal transmission between nerve cells and relieving the symptoms of the disease.

What is the stage of development of this medicine?

The effects of the medicine have been evaluated in experimental models.

At the time of submission of the application for orphan designation, clinical trials with the medicine in patients with CMT1A were ongoing.

At the time of submission, the medicine was not authorised anywhere in the EU for CMT1A or designated as an orphan medicinal product elsewhere for this condition. The three individual components of the medicine have been individually authorised at higher doses in the EU for other indications.

In accordance with Regulation (EC) No 141/2000 of 16 December 1999, the COMP adopted a positive opinion on 6 February 2014.

Opinions on orphan medicinal product designations are based on the following three criteria:

• the seriousness of the condition;
• the existence of alternative methods of diagnosis, prevention or treatment;
• either the rarity of the condition (affecting not more than 5 in 10,000 people in the EU) or insufficient returns on investment.

Designated orphan medicinal products are products that are still under investigation and are considered for orphan designation on the basis of potential activity. An orphan designation is not a marketing authorisation. As a consequence, demonstration of quality, safety and efficacy is necessary before a product can be granted a marketing authorisation.

EU/3/14/1260: Public summary of opinion on orphan designation: Fixed-dose combination of (R-S) baclofen, naltrexone hydrochloride and D-sorbitol for the treatment of Charcot-Marie-Tooth disease type 1A

Adopted Reference Number: EMA/COMP/94332/2014

Key facts

• Active substance:
  • (RS)-Bacoflen
  • naltrexone hydrochloride
  • D-sorbitol
• Intended use:
  Treatment of Charcot-Marie-Tooth disease type 1A
• Orphan designation status:
  Positive
• EU designation number:
  EU/3/14/1260
• Date of designation:
  26/03/2014
• Sponsor:

  Pharnext SA; 46 Rue Saint Lazare; 75009 Paris; France; Tel: [phone]; E-mail: [e-mail]