A Phase 1 Study of Heat/Phenol-Killed, E. coli - Encapsulated, Recombinant Modified Peanut Proteins Ara h 1, Ara h 2, and Ara h 3 (EMP-123) for the Treatment of Peanut Allergy
06/2013
Journal Article
Authors:
Wood, R.A.;
Sicherer, S.H.;
Burks, A.W.;
Grishin, A.;
Henning, A.K.;
Lindblad, R.;
Stablein, D.;
Sampson, H.A.
Secondary:
Allergy
Volume:
68
Pagination:
803-808
URL:
http://www.ncbi.nlm.nih.gov/pubmed/23621498
Keywords:
allergens; Immunotherapy; peanut allergens; Peanut allergy
Abstract:
{BACKGROUND: Immunotherapy for peanut allergy may be limited by the risk of adverse reactions. OBJECTIVE: To investigate the safety and immunologic effects of a vaccine containing modified peanut proteins. METHODS: This was a phase 1 trial of EMP-123, a rectally administered suspension of recombinant Ara h 1, Ara h 2, and Ara h 3, modified by amino acid substitutions at major IgE-binding epitopes, encapsulated in heat/phenol-killed E. coli. Five healthy adults were treated with 4 weekly escalating doses after which 10 peanut-allergic adults received weekly dose escalations over 10 weeks from 10 mcg to 3063 mcg, followed by three biweekly doses of 3063 mcg. RESULTS: There were no significant adverse effects in the healthy volunteers. Of the 10 peanut-allergic subjects [4 with intermittent asthma, median peanut IgE 33.3 kUA /l (7.2-120.2), and median peanut skin prick test wheal 11.3 mm (6.5-18)]; four experienced no symptoms; one had mild rectal symptoms; and the remaining five experienced adverse reactions preventing completion of dosing. Two were categorized as mild, but the remaining three were more severe, including one moderate reaction and two anaphylactic reactions. Baseline peanut IgE was significantly higher in the five reactive subjects (median 82.4 vs 17.2 kUA /l
