Oral immunotherapy (OIT) for food allergy - Twitter summary from 2012 #AAAAI meeting

This summary was compiled from the tweets posted by the following allergists/immunologists who attended the 2012 annual meeting of the American Academy of Allergy Asthma and Immunology (AAAAI): Stuart Carr @allergydoc4kidz, Robert Silge, MD ‏@DrSilge and Sakina Bajowala, M.D ‏ @allergistmommy. The tweets were labeled #AAAAI. The text was edited and modified by me.

Children with food allergy suffer more anxiety around food than children with diabetes. They may be the victims of potentially dangerous bullying.

Peanut desensitization pro-con debate:

Dr. Wasserman points out that smallpox vaccine, appendectomy and other advances became standard before completion of rigorous trials.

Dr. Sampson: doctors bloodlet, used leeches, and they thought they were helping. Just because we can doesn't mean we're doing the right thing.

Dr. Sampson asks: have we proven that one treatment is clearly superior to the other? Also, in a meta analysis, only 30% of patients enrolled in desensitizations for food allergy were confirmed to be truly allergic.

There is a high risk of reaction during peanut OIT. There is unclear outcome, long term risks are also unclear, such as causing eosinophilic esophagitis.

Dr. Wasserman: family practice, ENTs, and others are eager to start OIT. OIT should be done by board-certified allergists, and they should be ready to do it now. He argues that other providers (or even parents themselves) will fill the vacuum of allergists not performing peanut OIT. Dr. Wasserman argues that many parents reading abstracts/reports from meetings like the AAAAI and ACAAI and could even do OIT on their own or with other doctors.

The FDA does not approve treatments, they approve drugs and devices. He argues that peanut OIT protocol safety concerns can be managed effectively in the right clinic setting. Dr. Wasserman has treated 107 patients with peanut OIT with a 78% success rate. Quality of life in patients on peanut OIT vs. avoidance was remarkably improved - 90% improvement in QOL scores.

However, even Dr. Wasserman had 40 grade 4 reactions to peanut OIT in his practice. In Jones trial, 92% of patients reported adverse reactions.

Allergist offers desensitization to food allergic children: "There you go. Hit it" (video):

View more videos at: http://www.nbcdfw.com.

Stamen et al. showed no difference in tolerance when comparing milk and egg OIT to avoidance. 35% of patients were tolerant either way. Less than 15% of peanut allergic patients ever suffer from a life-threatening event.

Although desensitization is possible, there is still no evidence of induction of tolerance with OIT. Given the high risk, OIT should remain in research realm. No phase III trials for OIT have been undertaken.

Unknowns of peanut OIT: patient selection, dosing, adverse effects (EoE), length, mechanism of desensitization vs tolerance.

Dr. Sampson: question isn't whether we want to help our pts. We do. The question is whether peanut OIT is BETTER than standard of care. NIAID and FDA both do not support food immunotherapy at this time.

Matthew Bowdish MD ‏@MatthewBowdish: So far, I vote for Hugh Sampson's line of argument (Do good, or Do No Harm). Would we prescribe any other drug if it was only tested on a few hundred patients?

Dr. Sampson is concerned that if there was a death in the clinic, it could halt all academic studies of peanut OIT.

Dr. Hugh Sampson speaking for the con side: peanut OIT is not ready for prime time.

Dr. Wasserman rebuttal: high reaction rate in Jones study may have been function of strict dosing protocol. In practice, there is flexibility. Although FDA considers food a drug, most people consider food a food.

Wesley Burks discussed OIT for foods:

Peanut OIT

Peanut (PN) allergy is increasing in prevalence, it is more commonly associated with anaphylaxis, and inciting threshold is often lower than other foods.

Early studies targeted 300 mg PN for OIT maintenance. This dose is low but it is above the 100 mg threshold for most patients.

There is a risk for unanticipated OIT reaction (not during buildup) when the patient has fever, viral infection, exercise, menses.

There are reported symptoms with 15-25% of OIT doses, but severe reactions are noted in less than 1%. The drop-out rate of 10-20% is often due to delayed GI symptoms early on during OIT.

93% of patients were able to tolerate 13 PN after completing the OIT trial. There were corresponding changes in SPT, basophil responses, IgE/IgG4. Th2 responses decrease, with transient rise in Tregs with PN-OIT.

The question is: Desensitization vs. tolerance induction? Can OIT be stopped without recurrence of food allergy?

In a study of 19 patients on OIT for 33-70 months, OIT was stopped for 4 weeks: 11 remained tolerant to 5000 mg of PN.

If the baseline PN-IgE is higher than 85, it less likely that they will develop true tolerance.
Milk OIT

Milk SLIT vs. OIT: SLIT alone was unsuccessful. High-dose OIT after SLIT had a 80% success rate, but with more side effects.

Related: Sublingual Immunotherapy is Attracting Interest, Not Evidence - Medscape interviewed experts at 2012 #AAAAI http://goo.gl/arhcd

Mechanisms of allergen-specific immunotherapy (click to enlarge the image):

Allergists achieved highest use of social media by any specialty

During the 2012 AAAAI meeting, the allergists achieved the highest use of social media by any specialty. There are more than 100 allergists on Twitter and 30 of them posted simultaneously from the annual meeting, broadcasting thousands of tweets tagged with #AAAAI. The annual AAAAI meeting was attended by approximately 5,000 people. In comparison, the 30 allergists on Twitter reached 250,000 people (measured by TweetReach.com on 03/04/2012).

This summary was compiled from some of the tweets posted by  Stuart Carr @allergydoc4kidz, Robert Silge, MD ‏@DrSilge and Sakina Bajowala, M.D ‏ @allergistmommy. I would strongly encourage you to post updates on Twitter from the CME conferences that you are planning to attend in the future. Here is how to do it: Twitter for Physicians: How to use Twitter to keep track of the latest news and scientific meetings, and share information with colleagues and patients.

Disclaimer: The text was edited, modified, and added to by me. This is one of a series of posts that will be published during the next few weeks.

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