These promising results were reported in a paper published today in The Lancet Neurology. The study was designed and led by Eastman Dental Hospital facial pain consultant Professor Joanna Zakrzewska, who is supported by the UCLH Biomedical Research Centre.



It provides a glimmer of hope for patients as pain can be reduced to a tolerable level thanks to the novel substance known as BIIB074, the first drug in development specifically for this condition.



The sharp, shooting pain to the face or teeth can have significant psychosocial effects and may even lead to suicide. The bouts are triggered by touch, and can be set off by everyday tasks such as shaving, putting on make-up, showering, talking or brushing teeth.



The cause is usually an irritation of the trigeminal nerve, the cranial nerve responsible for the sensory innervation of the facial area, parts of the scalp, and the oral cavity.



Pain signals reach the brain via the activation of sodium channels located in the membranes of nerve cells. The sodium channel 1.7 is frequently expressed on pain-conducting nerves, and higher pain intensity is linked to higher channel activity.



Blocking this sodium channel – e.g. by local anaesthetic – inhibits the pain. In trigeminal neuralgia, the nerve damage is presumed to be at the base of the skull. However, this region is hard to reach by local injections and therefore requires drug treatment.



The substance BIIB074 tested in this study inhibits the sodium channel 1.7 in such a way that the more active this sodium channel gets, the stronger it is blocked by BIIB074. By contrast, currently available medications block the sodium channel 1.7 irrespective of the nerve activity, which commonly results in burdening side effects.



Unlike conventional drugs, which often cause tiredness and concentration problems, BIIB074 was not only effective but also very well tolerated. It will now be tested in larger patient groups.



Around 13 people in every 100,000 are diagnosed with trigeminal neuralgia every year and it is estimated there may be 50,000 sufferers in the UK.