Artemisia annua sublingual immunotherapy in children with
seasonal allergic rhinitis
To the Editor,
Artemisia pollen is the main aeroallergen of seasonal allergic
rhinitis (SAR) in summer and autumn.1,2Artemisia annua Allergens Sublingual Immunotherapy (SLIT) Drops
(Zhejiang Wolwo Bio-Pharmaceutical Co., Ltd., Zhejiang, China, National
Drug Approval No.: S20210001) is the only standardized SLIT preparation
approved in China for treatingArtemisia-induced allergic rhinitis with or
without conjunctivitis (AC).3 In this study, we aimed
to evaluate the safety and efficacy of A. annua- SLIT in children
with SARs.
Pediatric patients with at least a two-year clinical history ofArtemisia pollen-induced SAR with or without AC from Inner
Mongolia were included in this randomized, double-blind,
placebo-controlled, single-center clinical trial and randomized to
receive A. annua -SLIT or placebo at a 2:1 ratio for approximately
28 weeks. The combined score of medication and
rhinitis symptoms (CSMS; primary endpoint) and
combined score of medication and rhinoconjunctivitis symptoms (CSMRS;
secondary endpoint) were recorded to evaluate efficacy; adverse events
(AEs) were reported to assess safety.
Fifty-seven eligible patients aged 4–18 years were randomized into the
SLIT (n=38) and placebo (n=19) groups (Figure 1). Finally, 54 patients
(SLIT group: n=36; placebo group: n=18) completed the study with 3
patients withdrew by themselves. No significant differences were
observed between the groups in terms of sex, age, atopic status,
comorbidity of other allergic diseases, and CSMS and CSMRS scores in the
previous pollen season (P >0.05, Table S1).
The 2019 pollen season in Inner Mongolia was from 20th July to 7th
September (50 days; Figure 2A). The temporal variation of daily CSMRS in
both groups showed a similar trend of positive correlation with pollen
concentration throughout the pollen season (SLIT group: r=0.66, 95% CI:
0.53–0.76; placebo group: r=0.68, 95% CI: 0.56–0.77). The SLIT group
showed significant improvements in CSMS (1.55±0.81 vs. 1.97±0.73) and
CSMRS (1.46±0.75 vs. 1.88±0.75) compared with the placebo group
(P <0.05, Figure 2B–C). Fifty-three (98.1%) patients
experienced AEs [35, SLIT group; 18, placebo group] (Table S2). All
AEs were mild or moderate and resolved without any action or by
adjusting the dose of the study drug. There were no significant
differences in the incidence and severity of AEs between the groups
(P >0.05). Epinephrine use was not reported, and no
patients withdrew from the trial because of AEs. Furthermore, 94.4% and
100% of patients in the SLIT and placebo groups, respectively,
experienced treatment-related AEs (TRAEs), which frequently occurred in
the nose, eyes, throat, and tongue in both groups
(P >0.05, Figure 2D). The common TRAEs in children
with SLIT are shown in Figure 2E. Most TRAEs in the SLIT group were
mild, similar to those in the placebo group.
To our knowledge, this is the first study to report the efficacy and
safety of A. annua -SLIT in a Chinese pediatric population. Our
results showed a consistent trend of clinical efficacy improvements withA. annua -SLIT in children similar to those in
adults.4 Recently, a cumulative AE incidence of 93.0%
was reported with ragweed SLIT in children and adolescents, with no
serious AEs.5 The incidence of AEs in our study were
comparable to those in the previous study. Lou et al. found that the
most common TRAEs in adults with A. annua -SLIT were mild or
moderate.4,6 Our results showed a safety profile
similar to that in adults. No new safety signals emerged, and no throat
irritation was observed in adults.
In conclusion, 28-week A. annua -SLIT treatment was effective and
safe for children with SAR, with no major safety concerns. Investigating
the benefits of A. annua -SLIT in children will not only expand
its application for treatment but also provide the basis for
intervention in the early phase of SAR.