Short-course subcutaneous treatment with birch pollen allergoids greatly
improves symptom and medication scores in birch allergy
Abstract
Background: Subcutaneous immunotherapy has emerged as an
effective option for treating allergic diseases. Here, we assessed the
clinical impact of the mannan-conjugated birch pollen polallergoid T502
in birch pollen-induced allergic rhinoconjunctivitis. Methods:
In this prospective, randomized, double-blind placebo-controlled phase
III trial, 298 birch pollen–allergic adult patients were treated across
28 trial sites in Germany. Patients received either placebo or 23,000
mTU T502 subcutaneously over five pre-seasonal visits. Efficacy was
assessed by comparing the combined symptom and medication score (CSMS)
between placebo and T502 during the peak birch pollen season 2022.
Safety, tolerability and immunologic effects were also analysed.
Results: During the peak birch pollen season, the median CSMS
of the T502 group was reduced by 33.00% (p=0.002) compared to placebo.
The median daily symptom score and daily medication score were reduced
by 30.43% (p<0.001) and 56.25% (p=0.045), respectively. Health
related quality of life improved as reflected by reduction of RQLQ
values by 31.54% (p<0.0001). Production of Bet v 1 sIgG4
and sIgG increased up to 6.2-fold and 3-fold respectively in the T502
group (p<0.0001). The sIgE/sIgG4 ratio was strongly reduced in
the T502 group at V7 (-62.90%, p<0.0001). No fatalities nor
serious adverse events were reported. In total, 16 systemic allergic
reactions occurred (Grade I/II). Conclusions: Treatment with
T502 significantly reduced symptoms and medication need in
rhinoconjunctivitis patients. The treatment is well tolerated and safe.