Study design and oversight
The study was conducted as an open, prospective, observational,
multicenter study (Clinicaltrials.gov number NCT04269629). Patients were
recruited in 26 centers in eight European countries. The study was
approved by the ethics committee of the sponsor of the study (Medical
University of Graz; approval no. 26-442 ex 13/14) as well as local
ethics committees in each country, and patients gave their written,
informed consent.
Legally competent male and female patients aged 35 to 85 years with a
history of an SSR (≥ grade I according to the classification by Ring and
Messmer18) were eligible for the study. Absolute
contraindications to VIT and pretreatment with Omalizumab were exclusion
criteria.
After giving their written informed consent, patients were included
after carefully reviewing all inclusion and exclusion criteria at Visit
1. All data concerning the index sting reaction, laboratory parameters
like specific immunoglobulin E (sIgE) and tryptase levels and skin test
results were recorded as well as concomitant diseases and medication. If
patients agreed to receive VIT, data concerning the up-dosing phase
(premedication, venom preparation, up-dosing protocol, systemic AE
(classification by Ring and Messmer18), changes in
concomitant diseases, and medication) were recorded at Visit 2. There
was no standard up-dosing protocol used for VIT. All centers used their
own in-house protocols including conventional, cluster, ultrarush- and
rush-protocols.5 One year after reaching the
maintenance dose, Visit 3 was performed. At this visit, changes in
premedication, venom preparation, concomitant diseases and medication
were recorded as well as systemic AE during the maintenance phase and,
if applicable, the outcome of field stings and/or sting challenges. No
additional study-related visits were required. All procedures (diagnosis
and treatment of Hymenoptera venom allergy) had to be in concordance
with current EAACI guidelines5,19,20 and were
conducted individually by each study center.