NEW ORLEANS – The anti-epileptic agent lacosamide (Vimpat) appears to give relief to patients with refractory trigeminal neuralgia, researchers reported here.
Principal investigator Jeffrey Cohen, MD, an attending neurologist at Beth Israel Medical Center in New York City, looked at the drug in a pilot study of 11 patients – some of whom had failed to get relief even after surgical procedures.
Cohen, a member of the medical board of TNA--The Facial Pain Association, and neurology resident Shivang Joshi, MD, lead author, found that several patients achieved relief for more than a year with lacosamide and one achieved complete resolution of pain.
Action Points
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
- In this very small, retrospective chart review, lacosamide, which selectively enhances slow inactivation of voltage-dependent sodium channels, was associated with some response in most patients with refractory trigeminal neuralgia.
For seven of the 11 patients they had results from a Barrow Neurological Institute Pain scale, and five of those seven patients achieved some degree of pain relief, they reported in a poster presentation at the American Academy of Neurology meeting.
"Some of our patients had been in pain from trigeminal neuralgia for as long as 22 years, Joshi told ľֱ."
"In this small case series of patients with refractory trigeminal neuralgia, a majority of the patients responded at least initially, despite multiple previous medication trials and surgical procedures in some, he said."
In addition to surgical treatments that still did not relieve pain, the patients had been treated with a variety of drugs: anesthetics, anti-epileptics, opioids, nonsteroidal anti-inflammatory drugs, triptans, tricyclic antidepressants, and other medications. "These were truly refractory patients," Joshi said.
The dosage of lacosamide was not standard, but averaged around 200 mg a day.
Four of the patients were able to take lacosamide as an add-on therapy without experiencing further adverse effects; five other patients complained of dizziness; one patient reported fatigue and the other patient complained of constipation.
Image studies were performed in 10 patients, and these were negative in eight; two patients were observed to have meningiomas that could have caused the trigeminal nerve pain.
One 25-year-old man with right side trigeminal neuralgia did not receive any relief from treatment with lacosamide. An 80-year-old man and a 77-year-old man said that the treatment provided pain relief for two months; a 47-year-old woman reported 9 months of pain relief, and an 88-year-old woman reported 11 months of pain relief. The other six patients reported they have had relief of pain from 2 months to 12 months, and that relief is ongoing.
The median age of the patients in the study was 63; the mean duration of neuralgia was 10 years.
Shirin Issa, MD, assistant professor of neurology at the Montefiore Medical Center in Bronx, N.Y., told ľֱ that lacosamide might be helpful for some of these patients who have no treatment options available. The use of lacosamide is attractive, she suggested, because the side effects are minimal. "We are interested in trying it in our patients," she said.
Cohen and Joshi believe their results deserve to be pursued in a larger study. "Lacosamide was well tolerated and should be considered as a treatment option in chronic trigeminal neuralgia," Joshi said. "The positive results in a small case series such as this justify designing a clinical trial to determine safety and efficacy of lacosamide in trigeminal neuralgia."
Disclosures
The researchers had no disclosures. Shirin had no disclosures.
Primary Source
American Academy of Neurology
Source Reference: Joshi S and Cohen J, "Lacosamide as adjunctive therapy for refractory trigeminal neuralgia" AAN 2012; Abstract P03.224.