By Kerrie Smyres | October 27, 2005
Our options for headache preventives suck. Yeah, some work for some people and it is a matter of trial and error based on each person’s needs, but there aren’t any consistently effective drugs available. All in My Head author Paula Kamen shares this disconcerting information:
"…I heard a variety of doctors clearly make an assertion again about the inadequacy of the currently available preventives. ‘Interestingly, a majority of commonly used [preventives] have little evidence of efficacy. In contrast, almost all options have well documented adverse effects, often leading to a discontinuation of preventive therapy,’ read a summary in the program book leading to the presentation of Dr. David W. Dodick, the well-respected director of the Headache Program at the Mayo Clinic branch in Scottsdale, Arizona. This time the assertion was backed up by the citation of many studies, including a major federally sponsored one for 1999 done at Duke University." (Page 285)
If current understandings and expectations of a new compound, called tonabersat, play out, we may get a preventive of our very own. Tonabersat is the first in a class of compounds called "gap junction blockers." ("Gap junction blockers" refers to the overall class or type of compound, just like "antidepressants" refers to a group of different drugs.) Targeting a different type of brain action than other drugs that are used as preventives, gap junction blockers are thought to be a breakthrough for headache prevention.
Depending on how you look at it, there’s either a lot of promise or a lot of hype for tonabersat. Some of the soundbites include:
- “Tonabersat is an extremely interesting compound with a novel and very specific mechanism of action which means it is likely to be effective in prophylaxis of migraine.” (According to a past president of the International Headache Society who is working with the clinical trials)
- "Given the clear demonstration of clinical activity with tonabersat in previous migraine studies, we anticipate it showing real benefit." (Said the CEO of Minster Pharmaceuticals, the company that bought the rights to tonabersat and will develop the drug)
- Tonabersat "represent[s] the first major advance in the treatment of migraine since the introduction of Imigran [Imitrex in the US]." (From GlaxoSmithKline, who identified the initial compound and is expected to market the drug if it is approved)
I am wearily intrigued. A good headache preventive would be invaluable, but there are so many obstacles left that I can’t get excited yet. Trials are in the early stages. Results aren’t expected for a couple years and FDA approval won’t come until long after that. The drug may turn out to not be effective or may have unbearable side effects. Or it could work great and makes us all happy. Or be somewhere in between.