Antibody therapy: an experimental eczema treatment

For patients with extreme cases of eczema, a number of small trials worldwide hint at a possible future therapy: injections of an antibody to reduce the amount of other antibodies floating around the patients' systems.

Although evidence is currently slim that the treatment is effective for eczema, it has been approved for several years in the US as a treatment for extreme asthma.

Patients with eczema (and asthma) often have extremely high levels of a certain class of antibodies, immunoglobulin E (IgE). The IgE antibodies are somehow linked to allergies to food and environmental factors. When I say "somehow" I don't mean that nobody knows how antibodies binding to allergens results in an allergic reaction--we know the basic pathways of immunology. But just because a patient has a high level of IgE specific for dairy, say, does not mean the patient will have an allergic reaction to dairy. Science has not yet explained this.

New research suggests that for a certain fraction (~20%) of patients with eczema that resists treatment by steroids and other conventional treatments, injections of antibodies to IgE reduce the amount of circulating IgE and appear to cause relief of eczema symptoms.

That's right, an antibody to an antibody. The anti-IgE antibody has name, omalizumab, and it's expensive, in the range of $6,000-24,000/year. It was originally developed to treat severe allergic asthma, and is produced by Roche/Genentech and Novartis.

I learned about this treatment in a paper by DH Kim and colleagues in the journal Clinical and Experimental Dermatology. Kim is at Chung-Ang University College of Medicine in Seoul, and he and co-authors report having treated 10 adult eczema patients with eight injections of omalizumab over four months. (There were no control subjects, which is iffy but understandable in a small trial.) At the end of the cycle, two patients had greatly improved; five had improved moderately; and three had had no change.

When I searched on PubMed I found a number of other very small-scale studies of omalizumab for eczema: three patients in Thailand, one in Germany; nine in Spain. The website clinicaltrials.gov lists a 2006 trial of eight patients at Stanford University in California, but I can't find any publications that resulted.

In the recent Korean paper, the authors note that omalizumab is approved for use in patients with IgE levels up to 700 IU/ml. The patients in the Korean trial generally had IgE levels >5,000 IU/ml. The authors say that it seems clear that omalizumab is not completely removing IgE from the patients, but merely reducing the levels slightly. But even this slight reduction appears to have a systemic effect that means eczema symptoms are improved for some patients.