628:
A novel assessment of sustained unresponsiveness (SU) after long term sublingual immunotherapy (SLIT) in peanut allergic children: results of a 4 year phase II clinical trial.
Sunday, March 4, 2018: 4:30 PM
South Hall A2 (Convention Center)
Ahmad Hamad, MD, Edwin H. Kim, MD, A. Wesley Burks, MD FAAAAI, Deanna K. Hamilton, RN, Lauren Herlihy, RN MSN CPNP, Sarah A. Bennick, RN MSN CPNP, Pamela H. Steele, MSN CPNP AE-C
RATIONALE:

To date, SU has been studied as a binary outcome after an arbitrary period of avoidance. Characteristics about the duration of SU and the desensitization effect have not been well described.

METHODS:

Fifty-five subjects ages 1-11 years were enrolled in an open-label study of peanut SLIT using a maintenance dose of 4 mg. After 48 months of therapy, a 5000 mg DBPCFC was performed to assess for desensitization. A randomly selected period between 1-17 weeks of avoidance was then assigned to each subject after which an identical DBPCFC was performed to assess for SU.

RESULTS:

Forty-seven subjects completed the DBPCFC after 48 months of treatment with a median successfully consumed dose (SCD) of 0 mg (0-425 mg) prior to treatment and 2900 mg (100-5000 mg) after 48 months. Peanut IgE levels dropped significantly over the treatment period: Median 84.7 kU/L (0.3-1804) at entry, to 11.2 kU/L (0.05-970) after 48 months.

Thirty subjects completed the randomly assigned post-avoidance DBPCFC demonstrating an estimated decrease in SCD of 111 mg/week of avoidance. Only one subject demonstrated a decrease in SCD below 300 mg after avoidance (100 mg was tolerated at 48 months and at 1 week post avoidance)

CONCLUSIONS:

Long-term treatment with peanut SLIT successfully desensitizes subjects to a median dose well above that expected in an accidental exposure. Our novel assessment of SU demonstrates a steady decrease in SCD over time but at a slower rate than expected with the majority of subjects maintaining a clinically significant SCD even after 17 weeks of avoidance.