Effect of intranasal corticosteroid on pre-onset activation of eosinophils and mast cells in experimental Japanese cedar pollinosis

Focused allergic rhinitis practice parameter for Canada

Allergic rhinitis (AR) is a prevalent disease in Canada that affects both children and adults. Several guidelines for the management of AR have been published by professional allergy societies worldwide. However, there are regional differences in the clinical management of AR, and regulatory approval of some AR pharmacotherapies varies among countries. Thus, six research questions specific to the treatment of AR in Canada were identified for this focused practice parameter. Reviews of the literature published since 2016 were conducted to obtain evidence-based support for the responses of the Work Group to each research question. In response to research question 1 "In patients with symptoms indicative of AR, is serum-specific IgE sufficient to identify candidates for immunotherapy or is a skin prick test mandatory?" the Work Group concluded that either sIgE testing or skin prick test are acceptable for diagnosing AR and guiding immunotherapy. In response to research question 2 "When taking into account the preferences of the patient and the prescriber (stakeholder engagement) should second-generation oral antihistamine (OAH) or intranasal corticosteroid (INCS) be first line?" the Work Group concluded that existing guidelines generally agree on the use of INCS as a first-line therapy used for AR, however, patient and provider preferences and considerations can easily shift the first choice to a second-generation OAH. In response to research question 3 "Is a combination intranasal antihistamine (INAH)/INCS formulation superior to INCS plus OAH? Do they become equivalent after prolonged use?" the Work Group concluded that that the combination INAH/INCS is superior to an INCS plus OAH. However, there was insufficient evidence to answer the second question. In response to research question 4 "Do leukotriene receptor antagonists (LTRA) have a greater benefit than OAH in AR for some symptoms to justify a therapeutic trial in those who cannot tolerate INCS?" the Work Group concluded that LTRAs have inferior, or at best equivalent, daytime or overall symptom control compared with OAH, but LTRAs may improve nighttime symptom control and provide benefits in patients with AR and concomitant asthma. In response to research question 5 "Should sublingual immunotherapy (SLIT) tablets be considered first-line immunotherapeutic options over subcutaneous immunotherapy (SCIT) based on the evidence of efficacy?" the Work Group concluded that the choice of SLIT or SCIT cannot be made on efficacy alone, and differences in other factors outweigh any differences in efficacy. In response to research question 6 "Based on efficacy data, should ALL patients seen by an allergist be offered SLIT or SCIT as a treatment option?" the Work Group concluded that the efficacy data suggests that SLIT or SCIT should be used broadly in patients with AR, but other clinical concerns also need to be taken into consideration.

The add-on effect of an intranasal antihistamine with an intranasal corticosteroid in Japanese cedar pollinosis

OBJECTIVE

Combination intranasal drugs with a corticosteroid and antihistamine are available in several countries with better effect than treatments with single agents. However, it remains unclear whether this effect is also seen in Japanese cedar pollinosis (JCP), the most prevalent seasonal allergic rhinitis in Japan. We investigated the effect of an add-on intranasal antihistamine with an intranasal corticosteroid in JCP during the pollen dispersal period. (UMIN000025508) METHODS: We performed a double-blinded, randomized, placebo-controlled trial from March 1 to 14, 2017. Patients (n = 20 per group) received either a mometasone furoate nasal spray (MFNS) plus a levocabastine nasal spray (levocabastine group) or MFNS plus a placebo nasal spray (placebo group). The primary endpoint was the difference in the total nasal symptom score (TNSS) after treatment between the two groups. Differences in the total ocular symptom score, total symptom score, total medication score, total symptom-medication score, and five individual symptoms as well as safety were the secondary endpoints.

RESULTS

The change in the TNSS from baseline was significantly greater in the levocabastine group than in the placebo group. A significant reduction in the TNSS was observed more than 6 days earlier in the levocabastine group than in the placebo group. Such add-on effects were also seen in the secondary endpoints. Both treatments were well-tolerated.

CONCLUSION

The intranasal antihistamine provided better control of not only nasal symptoms, but also of ocular symptoms, and decreased the need for rescue medications when added to intranasal corticosteroid treatment in JCP patients.

Executive summary: Japanese guidelines for allergic rhinitis 2020

The Practical Guideline for the Management of Allergic Rhinitis, the fist guideline for allergic rhinitis in Japan, was prepared after a symposium held by the Japanese Society of Allergology in 1993. The current 9th edition was published in 2020 and is widely used today. The most recent collection of evidence from the literature was supplemented to the revised guideline to incorporate evidence-based medicine. The revised guideline includes updated epidemiology of allergic rhinitis in Japan, a figure representing the mechanisms of allergic rhinitis in both the onset and sensitization phases with the introduction of regulatory T cells and type 2 innate lymphoid cells, practical assessment for diagnosis, new pharmacotherapy agents such as anti-IgE mAb and a new drug delivery system for antihistamines, sublingual immunotherapy for children, dual sublingual immunotherapy for house dust mites and Japanese cedar pollen extract, new classification for surgery for allergic rhinitis, and treatment and prescriptions for older adults. An evidence-based step-by-step strategy for treatment is also described.

Determining an Appropriate Time to Start Prophylactic Treatment with Intranasal Corticosteroids in Japanese Cedar Pollinosis

Prophylactic treatment with intranasal corticosteroids is effective for pollen-induced seasonal allergic rhinitis. However, the appropriate time to start this treatment remains unclear. We performed a double-blinded, randomized, placebo-controlled trial. Starting on 1 February 2014, patients with Japanese cedar pollinosis received either fluticasone furoate nasal spray (FFNS) for 8 weeks (Group A: n = 24), placebo nasal spray for 2 weeks followed by FFNS for 6 weeks (Group B: n = 23), or placebo for 4 weeks followed by FFNS for 4 weeks (Group C: n = 23). The primary endpoint was comparison of the total naso-ocular symptom score (TSS). Secondary endpoints including the increment cost effective ratio (ICER) were also determined. Continuous pollen dispersion began on the 24th of February. Therefore, Group A and Group B received 3-weeks and 1-week of prophylactic treatment, respectively, whereas Group C received post-onset treatment. During the peak pollen-dispersal period, significant differences in TSS were seen between the groups, particularly between Group A and C. The ICER of Group B vs. Group C was lower than that of Group A vs. Group C. These results suggest that long-term prophylactic treatment with FFNS is clinically the most potent treatment, whereas short-term prophylactic treatment is cost effective for pollen-induced allergic rhinitis.