Acute, severe and anaphylactoid reactions are very rare with low-molecular-weight iron dextran, CosmoFer.

Sir,

It was with interest and surprise that I read the article by Liliana Schaefer and Roland M Schaefer [1].

In this article, Liliana and Roland Schaefer do not distinguish between the adverse drug event profile of the old high-molecular-weight iron dextrans that have been withdrawn from the market of Europe ∼20 years ago and the low-molecular-weight iron dextran marketed in 1992 as INFeD® in the US and in 2001 as CosmoFer® in Europe and overseas. The product is produced by Pharmacosmos in Denmark and marketed in more than 40 countries.

Numerous articles, [2-7], including the Chertow article [5] referenced by the Schaefers, document that the high-molecular-weight iron dextran has many times more adverse drug events than the low-molecular-weight iron dextran. The high-molecular-weight iron dextran is today marketed practically only in the USA under the brand Dexferrum where the active pharmaceutical ingredient is produced by Vifor International. Vifor also produces iron sucrose Venofer®.

Low-molecular-weight iron dextrans have now been administered in more than 70 million doses of 100 mg. The CosmoFer® SmPC in Europe was updated in June 2007 and concludes that anaphylactoid reactions are less than one in ten thousand; this is the same as in the SmPC for Venofer® iron sucrose.

I would expect that the next revision of the European Best Practice Guidelines reflects the updated knowledge about low-molecular-weight iron dextran, CosmoFer®.

Conflict of interest statements. During 1999–2005 President of Nebo A/S launched CosmoFer® worldwide. Nebo A/S has been merged into the mother company Pharmacosmos A/S where I have the same responsibility for CosmoFer® as Executive Vice-President of the Pharmacosmos Group. I am a co-author of the referenced Chertow articles published in Nephrol Dial Transplant [4,5].