The market for Sumatriptan (the generic version of Imitrex/Imigran) is complicated

Danish pharmacies are obliged to supply their cuztomers with the cheapest brand of the prescribed medicine. That makes sense, both to the migraineur and to health service. The trouble is that one brand of Sumatriptan, Sandoz, contains aspartame and aspartame may trigger migraine attacks in predisposed individuals.

The price per tablet also makes the market obscure. In early January six different companies sold 100 mg Sumatriptan at a lower price than 50 mg. From 11. to 23. January, this is the case for 'only' three companies, as three companies upped the price for their 100 mg tablets. Since 25. January 5 products have this reversed pricing.

We conclude that the price we pay for our medicine bears no relation to the neither the production costs nor the cost of packaging. This seems to indicate that the Danish price system with fixed prices for two-week periods cannot handle a competitive market as we see it for Sumatriptan.

We advice all triptan users to double-check the medicine - for aspartame content and for price.

The Danish Migraine Association cannot see any good reason to add aspartame to tablets that are to be swallowed and never tasted. Tablets that dissolve in the mouth also contain aspartame to mask the unpleasant taste of the triptan. We can see the point in masking the taste, but do not understand why aspartame has to be added to the dissolving tablets if other sweeteners, that are not migraine triggers, could be used.

Aspartame is approved for medicines in the EU. We hope this approval can be revised so that an exception will be made for migraine medicine, as it is clearly not in the patient's best interest to take medicine that increases his or her migraine. The International Headache Society (the doctors' profssional internatinal organisation)is aware that aspartame is a migraine trigger, and states on page 44 in the 2005 version of The International Classification of Headache Disorders:

Trigger factors (precipitating factors) Trigger factors increase the probability of a migraine attack in the short term (usually less than 48 hours) in a person with migraine. Though some trigger factors have been reasonably well studied epidemiologically (eg, menstruation) or in clinical trials (eg, chocolate, aspartame), causal attribution in individual patients may be difficult.

We have collected abstracts of the most recent publications on the effect of aspartame on migraine.

Aspartame is found in Sumatriptan tablets from Sandoz as well as in Maxalt Smelt and Zomig Rapimelt tablets.

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The low price for filmed Sumatriptan tablets has reduced the total costs for Sumatriptan from above 60 DKK per dose on average to around 30 DKK per dose. However, the recent turmoil in the price formation seems to have influenced the total cost per daily dosis in an upwards direction.

The lower costs of the copy medicine is equivalent to a total saving for migraineurs and the health service of around 100 million DKK per year (around 15 million Euros or 20 million $US). Denmark has a population of around 5½ million people.

On an annual basis around 700,000 tablets of 100 mg Sumatriptan are sold as well as 700,000 50 mg Sumatriptan tablets (data from http://www.medstat.dk/). The sales of triptans increase by approximately 6% per year.

Data from ORDIPRAX.

Danish medicine prices are fixed for 2 weeks at a time (see an explanation in Danish on Medicinpriser.dk )

Changes in the market?

Even though Sumatriptan is considerably cheaper than the rest of the triptans, the users still hang on to the other triptans. However, Sumatriptan, the low price brand, has increased its sales by around 10% after the expiry of the patent.

Sumatriptan covers just over 60% of the market for triptans in Denmark.

However, Eletriptan (Relpax) has doubled its sales from 2003 to 2007, being promoted by regional and national recommendations during the period 2003 - 2006. The national recommendation list is now much more informative (see the national recommendations for migraine medication in Danish), and the sale of Relpax is falling.

What happens now?

The low price on Sumatriptan may have several consequences. Migraineurs are no longer limited in their choice of medicine, as the financial incentive to reject triptans has gone. Maybe we will see an increased usage of triptans. Maybe we will see more medicine induced migraine due to the price barrier being removed. Maybe we will see fewer sick days due to migraine.

Whatever happens, it may set a precedence on the world market.

We follow the development in prices for triptans and hope to see a price adjustment in triptans other than Sumatriptan.

What happened in Denmark?

On our request, the Danish authorities decided in early 2006 that Imigran Sprint (the rapid formulation) and the filmed tables are interchangeable as the active compound is the same and both are tablets to be taken orally.

GSK withdrew Imigran filmed tablets (50 and 100 mg) from the Danish market during the winter of 2005-06. Imigran Sprint, which had its own patent rights, had been introduced during 2005, and GP's were getting used to thinking about the new 'Sprint-tablets' as the usual Imigran. We interpreted this as a way of ensuring that the high prices for Imigran could be maintained even after the expiry of the first patent. Obtaining equivalence between Imigran Sprint and the filmed tablets opened the market for generic filmed tablets, and hence the possibility of a price reduction.

In the Danish system, pharmacies must offer the cheapest brand within the group of brands that can be substituted. Medicine subsidies in Denmark are based on the price of the cheapest brand (including generic brands), so subsidies for Imigran Sprint (which costs around 10$US for one tablet) is now calculated from a price of less than 1$US. That means there is hardly any subsidy provided for Imigran Sprint, unless the GP has obtained a special permission from the Danish Drug Administration to have the full subsidy for a more expensive brand.

After the expiry of the patent for the Imigran filmed tablet in Denmark in May 2006, generic tablets of filmed Sumatriptan (the traditional type of tablet) were introduced, as they are now given out by the pharmacies when the prescriptions say Imigran. The filmed tablets are sold under the name of Sumatriptan, and marketed by GSK as well as by other companies.

Imigran Sprint (the rapid formulation Imitrex) is a slightly modified tablet, built like an M&M chocolate pastil (Smarties) with a hard shell and the active ingredient (Sumatriptan) inside the shell. When the shell comes in contact with water in the stomach, it breaks and releases the contents. This tablet is marketed in other parts of the world as Imitrex, with no indication that it is a new formulation. The filmed version has been removed from the market in large parts of the world after the introduction of the rapid onset Imitrex, possibly as an attempt to maintain a high price level for the active ingredient sumatriptan.

The relief obtained from the filmed tablets (the traditional ones) is only marginally slower than the relief obtained from the Sprint version.

Updated 25. January 2010

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Brain lesions not limited to women with aura migraine in middle age

A new long term study of migraineurs from Iceland concludes that women with migraine with aura in their middle life (around 50 years age) have an almost doubled risk of forming brain infarcts (small lesions), compared to non migraineurs (see the abstract of the original publication here and a press release in Modern Medicine.

Generally, it is expected that around one migraineur in ten have migraine with aura. In this study of Icelandic migraineurs, from a large random sample of individuals in 1967, 278 women had migraine with aura while only 179 had migraine without aura. The reason for this unexpected proportion of aura-migraineurs seems to be that the researchers in 1967 used a wider definition of aura than is used today.

So the conclusion of the study is not only valid for women with migraine with aura in their middle age, but also for some of the women who would, nowadays, be told that they do not have aura.

Brain infarcts are found in 25 - 40% of older persons, and the infarcts are not been linked to functional problems for the older migraineurs.

Updated 27. June 2009

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The Danish Migraine Association is an independent patient organization that works for the benefit of Danish migraine patients and their relatives.

We provide information about migraine, its treatment and causes, and support research about migraine. We also provide a forum for the exchange of experiences and advice to migraine patients.

The Danish Migraine Association aims to inform patients and society at large about all aspects of migraine. We arrange lectures and publish a quarterly magazine (in Danish) with excerpts from the latest scientific research, letters from members, and general information of interest to migraine sufferers. We also speak up in public when appropriate.

Why become a member of The Danish Migraine Association?

The Danish Migraine Association works for migraine patients and their relatives. We inform patients about what they themselves can do to have a better life (this home page is part of that information) and we have meetings, lectures and publish a magazine four times a year.

Contact persons around the country form local groups that meet informally and we have lectures in Copenhagen as well as around the country. MigræneNyt (our magazine in Danish) contains summaries of the latest news from research, and the contact telephone is open throughout the day for anyone who needs a chat or a sympathetic ear.

For more information please contact

The Danish Migraine Association
e-mail Migrænikerforbundet's office or phone +45 7022 0131

or write to

Migrænikerforbundet
Postboks 115
DK-2610 Rødovre
Denmark