Study design
This multicenter, two-armed, real-world study included patients with AR
and IgE-mediated sensitization to dermatophagoides pteronyssinus(Dp) and/or dermatophagoides farinae (Df). Patients were
undergoing ongoing SCIT with a treatment visit during the period between
February 1 and May 31, 2020 (during the COVID-19 outbreak in China) for
the first visit (V0) and for follow-up 1-year later (V1). They were
enrolled from the departments of otorhinolaryngology from five tertiary
hospitals (in three provinces in southern China), including Zhujiang
Hospital of Southern Medical University, the Third People’ s Hospital of
Changzhou, the First People’s Hospital of Foshan, the People’s Hospital
of Guangxi Zhuang Autonomous Region and Liuzhou People’s Hospital.
Approval to conduct this study was obtained from the institutional
review board of all participating hospitals. The patients in this study
were all from hospitals not designated for COVID-19 infected patients.
Special measures were performed to prevent patients with a COVID-19
infection from entering the hospitals. The patients received at least
one reminder call a week prior to their SCIT appointment.
A standard protocol for SCIT ® (50% Dp and 50% Df, Allergopharma
Joachim Ganzer KG, Reinbek, Germany) was used for all patients in both
the build-up and maintenance phases. For the build-up phase, SCIT® dose
was gradually increased every 1-2 weeks until the maximum tolerated dose
for the individual was reached, and the treatment for a total of 18
weeks including the dose increases.. In the build-up phase, injections
at an interval of more than 2 weeks were regarded as delayed treatment.
For the maintenance phase, the maximum tolerated dose was given
subcutaneously every 4-6 weeks for at least 2 years. During the
maintenance phase, injections at an interval of more than 6 weeks were
regarded as a delayed treatment. The dosage adjustment plan in the case
of delayed treatment for SCIT patients in the build-up phase was as
follows: (1) > 2 weeks, the dose was adjusted to 50% of
the last dose; > 4 weeks, start again from the initial dose
concentration. The dosage adjustment plan in the case of delayed
treatment for SCIT patients in the maintenance phase was: (1)
> 6 to 8 weeks, the dose was adjusted to 50% of the last
dose; (2) > 8 weeks, the dose was adjusted to 5% of the
last dose; (3) > 52 weeks, and the treatment was resumed
from the starting concentration. The course of SCIT in this study was at
least 3 years.