Addex preclinical drug slows inherited neuropathy

Addex Therapeutics has released positive preclinical results for ADX71441 in an animal model of Charcot-Marie-Tooth disease type 1A (CMT1A), a rare and incurable inherited neurological disease that leads to motor and sensory neuropathy, causing increasing muscle weakness and numbness.

Patients with CMT1A express too much of the protein peripheral myelin protein 22 (PMP22). While certain amounts of this are needed for the myelin sheath that protects nerves, too much or too little leads to neuropathy. In rats with a disease that mimics CMT1A, Addex's ADX71441 cut the levels of PMP22, reduced the number of nerves with damaged myelin sheaths and increased the nerve signals to muscles. The drug also prevented the loss of grip strength in the treated rats.

"Current CMT1A therapies are primarily symptomatic such as physiotherapy and only focus on the manifestations of the disease," says Michael Sereda of the Max Planck Institute for Experimental Medicine.

Addex's drug, which is a GABA-B receptor-positive allosteric modulator, could have potential to slow the progression of the disease by lowering the levels of PMP22 overexpression. In preclinical results announced in October 2012, ADX71441 also reduced alcohol intake in a rodent model of alcohol binge drinking. The current lead indication for the drug is in spasticity associated with multiple sclerosis, and the company is planning a Phase I trial for the first half of 2013.

Addex had an eventful year last year. After a surge in its share value on positive data on a Phase IIa study of its Parkinson's disease therapy, dipraglurant, the company announced (perhaps surprisingly) that it was axing 28 members of its staff in Geneva to improve efficiencies. According to the website, the company is seeking a partner for dipraglurant.

- read the press release