[Anti IgE therapy (off label use) in severe peanut allergy with recurrent anaphylaxis]

A 16-year-old male patient experienced a severe asthma attack in 2004 after contact to peanut doodles without having ingested any of it. In autumn of 2005 and spring of 2006 he suffered from anaphylaxis after unknowingly ingestion of peanut traces.

Skin and serologic testing revealed a profound allergy to peanut. Oral provocation did not demonstrate any other potential causes of anaphylaxis.

Due to the severe nature of the two anaphylactic episodes to peanut traces within six month despite previous diet counselling, we initiated an off label treatment with recombinant humanised monoclonal anti-IgE antibody Omaluzimab (Xolair, 300 mg once a month). In July 2007 we re-challenged our patient with increasing doses of up to 1/2 peanut in a placebo-controlled fashion while he was being monitored in the intensive care unit. He experienced only a mild oral allergy syndrome. Since January 2008 we have been attempting to achieve a specific oral tolerance induction. Furthermore, we discuss the requirements for the off label use of substances.