Thursday, August 13, 2015

Oral Immunotherapy...Just The Facts (Part One)

The fact that Aaryn and I are huge believers in Oral Immunotherapy is no secret at this point.  We have both publicly shared our story in an attempt to put a human face to a often debated topic.  Today, Aaryn and I are excited to introduce Part One of a Four Part Series on Oral Immunotherapy...Just The Facts.

Earlier this summer, Aaryn and I reached out to the greater allergy community and asked "what are the fears, myths, or questions you have/have heard about OIT?".  Foolishly, I posted this question before heading to bed, thinking we would get a few questions.  The next morning, I woke up to several dozen notifications.  When all was said and done, we had over 50 questions! That list was reviewed, and 20 questions remained (for those wondering about the other questions, some were combined, others will be saved for a less fact-focused, more experience centered article).  We reached out to none other than the renowned (and much loved) Dr. Richard Wasserman of The Dallas Food Allergy Center.  We are thrilled that he agreed to answer our (fairly long) list of questions!

PART ONE: The Basics

OrAAA: What does your protocol look like? What is the ultimate goal? 

Dr. Wasserman: We begin with a very low dose, no patient has ever reacted to our first dose. On day one we give several doses over a several hour period. After the first day, we do dose increases weekly. The target dose is a full portion of the food. Our goal is normal life. For most patients, the goal is to freely incorporate the food into their diet. Not all patients are able to do that. Some families decide that they want to continue to avoid the problem food even after they complete OIT.


OrAAA: Can you explain the concept of OIT and how it differs from the peanut patch, a pill, or the FAHF-2 work of Dr. Li? 
Dr: Wasserman: OIT, sublingual and the patch all work on the principles of desensitization that introduce progressively increasing doses of allergen over time to alter the allergic response. This approach has been used by allergists for more than 100 years. The mechanism of action of FAHF-2 is still being worked out.

OrAAA: Many of us have kiddos with several issues going on at once...how do other diseases impacts the process (Environmental allergies, asthma, Mast Cell Activation Disorder/Syndrome, EOE, FPIES)?  Are there any absolute "no's"? 
 
Dr. Wasserman: Whenever a patient begins OIT, there will always be a question of whether the symptom was caused by the OIT food. Therefore, other allergy related problems need to be well controlled before OIT is started. This applies to allergies, asthma and eczema. We have no experience with OIT in patients with mast cell activation syndrome or idiopathic anaphylaxis and would be reluctant to try in those cases because it would be hard to differentiate a food reaction from other problems. The understanding of EoE and FPIES is limited and the risks of introducing a food known to cause a reaction are unknown but those problems are difficult enough without adding the potential complications of OIT. We would not begin OIT in a patient with EoE or FPIES.

OrAAA: What are the odds that my kiddo will develop EOE/FPIES/a new food allergy/exercise induced anaphylaxis?
 
Dr. Wasserman: We believe that about 3-5% of our OIT patients develop clinical symptoms suggestive of EoE. Some groups have seen a higher incidence. Early on, when these symptoms occurred (vomiting hours after the OIT dose), we stopped OIT. Based on the work of our colleague, Dr. Katz in Israel, we now reduce the dose until symptoms resolve, hold at the lower dose for several months, and then increase again. This works for most patients. 

Food/exercise anaphylaxis has been known for many years. Exercise too soon after doing is a significant risk for a reaction. We require a two hour waiting period after dosing before athletic activity.
OrAAA: There seems to be a lot of different protocols out there (rest periods, bite proof vs. unlimited consumption, once or twice a day, etc.).  Do you know why this is? 

Dr. Wasserman: Each allergist develops the approach that he or she believes will work the best. Each OIT study can only tell us how well that protocol seems to work. The only way to know if one is better than another would be to do a study comparing them in a controlled fashion. It is unlikely that such a study will ever be done. The protocol that we use today has been modified several times based on review of our experience. We collected detailed information about the experience of each OIT patient and review that information at least annually. Based on what we see in the compiled data we modify our approach to make it safer or better tolerated. Among those who have reported their experience, the results are pretty much the same.
OrAAA: Bite proof or unlimited...which is the better goal?
 
Dr. Wasserman: It depends on the individual patient. We aim for unlimited incorporation of the food into the diet. Very few children are so difficult to treat that they can't reach the target dose but it does happen. So children really hate the taste of the food, especially peanut. For those children it doesn't really make sense to push to the full dose. The right goal is the goal that is right for the individual child and family.


OrAAA: Will we have to dose forever? Why? 
Dr. Wasserman: We really don't know. It appears that some children develop sustained unresponsiveness with profound reductions (>98%) of the food specific IgE. These children don't have to dose daily. At this point, it seems that most OIT patient will need to dose indefinitely. The allergic response is still only partially understood. We don't know why some people develop food allergy nor why some respond to OIT better than other.




OrAAA: How can I know OIT is safe when it is not FDA approved?
 
Dr. Wasserman: There is a lot of misunderstanding of the role of the FDA in OIT, even by doctors. The FDA approves drugs and devices. It never approves treatments. It is likely that the FDA will eventually approve the peanut treatment being developed by Aimmune. I see this as a disaster for patients. I can treat many patients for a $6 bag of peanut flour. When the FDA approves peanut treatment, I expect that the peanut drug will cost thousands of dollars per patient excluding physician's fees.

OrAAA: Is there a chance that OIT can make an allergy WORSE?
 
Dr. Wasserman: I don't think that OIT can make an allergy worse. 
OrAAA: There seems to be pretty good consensus that adolescents are at risk for poor outcomes associated with anaphylaxis.  Is this biological or related to another factor? If it is biological, does that mean that it could make OIT dangerous at this age?
 
Dr. Wasserman: It is hard to know for sure but I think the problem with adolescents is that they deny early symptoms and don't carry epinephrine and therefore treatment is delayed. We do know that delay in the use of epinephrine is associated with bad outcomes.

OrAAA: Can you talk about doing OIT with children with special needs (such as kids with I/DD or Communication Disorders)?  Does this change anything with the OIT process?
 
Dr. Wasserman: Children receiving OIT need to be developmentally able to fully cooperate with the process, communicate subtle symptoms and be willing to eat a food every day as though it was a medicine. Each child should be evaluated individually before start OIT.
OrAAA:  If OIT in the private practice is safe, why is it so controversial? Why the lack of practices?
 
Dr. Wasserman: It has been argued publicly that more studies are needed before OIT can be offered by allergists outside of studies. Since that statement was made in a public forum, there have been more than 400,000 ER visits for food allergy and opponents say we still need to wait for more studies. OIT is a complex and demanding procedure for patients, their allergists and their allergists' office staffs. Not every office will be equipped or willing to undertake the effort to offer this therapy. I believe that OIT should be available but I don't believe that every allergist should offer OIT.
 
Dr. Wasserman is Medical Director of Pediatric Allergy and Immunology at Medical City Children’s Hospital and managing partner of Allergy Partners of North Texas. He served on the full time and clinical faculty in the Department of Pediatrics at the University of Texas Southwestern Medical School from 1988 to 2015.

He was raised in New York, where he graduated cum laude with Honors in Chemistry from Hobart College. He studied at Mt. Sinai School of Medicine and City University of New York Graduate School receiving his PhD in immunology from CUNY and his MD from Southwestern Medical School. He did an internship and residency in pediatrics and a fellowship in bone marrow transplantation and immunology at The Children’s Hospital of Philadelphia. After a fellowship at The Rockefeller University (Kunkel Lab) he became Chief of Pediatric Allergy and Immunology and Pediatric Program Director at Southwestern Medical School.

After six years as fulltime faculty, Wasserman started a private practice in allergy and immunodeficiency and DallasAllergyImmunology Research that has conducted more than 110 FDA approved studies.  He served as Director of the Immunology Clinic at Children’s Medical Center of Dallas for 19 years and taught immunodeficiency to medical students for more than 25 years. He is a past president of the Pediatric Society of Greater Dallas and has edited the Society Newsletter for fifteen years.  Wasserman is currently a Trustee of Hobart and William Smith Colleges and a past member of the AAAAI Board of Directors.

Wasserman has coauthored more than 100 peer-reviewed publications, case reports, book chapters and reviews and 80 International Meeting posters and presentations.