Q:

5/23/2013
I have one allergic rhinitis patient on allergy immunotherapy who asked me if maintenance weekly injection, instead of monthly injection, will enhance immunotherapy effect quicker than 3-5 years. She thought she will live here for at least 3 years when she started her immunotherapy, but she may move out of the US in the next 6 months. If that plan is finalized, she wonders if she will get the most benefit out of immunotherapy by getting maintenance shot weekly. There is a chance that in the country she is moving, no physician is providing allergy immunotherapy service that she is receiving now. I do not know if there is any literature out there on such a topic, but any inputs would be appreciated. Thank you so much in advance.

A:

Thank you for your inquiry.

I have not been able to find any study addressing this issue, but since the response to allergen immunotherapy is dose dependent, I imagine that there would be some benefit, in your patient’s case, of administering maintenance injections on a weekly basis. However, since I have not been able to document this opinion, I am going to ask Dr. Harold Nelson, who is an international expert in allergen immunotherapy, for assistance. As soon as we receive his response, we will forward it to you.

Thank you again for your inquiry.

Sincerely,
Phil Lieberman, M.D.

We received a response from Dr. Harold Nelson. Thank you again for your inquiry and we hope this response is helpful to you.

Sincerely,
Phil Lieberman, M.D.

Response from Dr. Harold Nelson:
You are correct, there are no studies. However, in our year long dosing study with cat hair and dander extract, we found that the immunologic differences in favor of the dose containing 15 mcg of Fel d 1 were present at 5 weeks (when they achieved maintenance) and that there were no similar changes in the dose with 3 mcg after a year of maintenance. That suggests to me that the total dose is not determinant of response, but rather the quantity of the individual maintenance dose. In the absence of data, my bias is that giving shots weekly would not have any more lasting effect that giving them monthly. As to the duration, Des Roches showed some had lasting benefit with relatively brief (one year) duration, but that the probability of long-term benefit increased with duration, especially after 3 years of treatment.

Regards,
Harold Nelson, M.D.

AAAAI - American Academy of Allergy Asthma & Immunology