Allergen Immunotherapy Outcomes and Unmet Needs

Mapping naso-ocular symptom scores to EQ-5D-5L utility values in Japanese cedar pollinosis

BACKGROUND

The total naso-ocular symptom score (TSS) is widely used as an endpoint to evaluate the severity of seasonal allergic rhinitis. However, it is not a generic preference-based measure. We sought to develop an algorithm for mapping between the TSS and health utility in Japanese cedar pollinosis (JCP). We also performed a cost-utility analysis of sublingual immunotherapy (SLIT) for JCP by using this algorithm.

METHODS

Patients with JCP filled out the TSS questionnaire and EQ-5D-5L simultaneously during the pollen season in 2019 and in 2020. We estimated a direct utility mapping model by regressing responses to individual TSS questions directly onto utility. The incremental cost-effectiveness ratio (ICER) of active SLIT to a placebo was determined by examining the drug expense and the estimated quality-adjusted life year (QALY) using a dataset from a double-blind placebo-controlled clinical trial.

RESULTS

A total of 238 records were included for analysis. The estimated utility decreased with increasing severity of rhinitis. Patients with comorbid asthma showed lower utility. A negative and significant correlation was seen between the TSS and utility in both 2019 and 2020. The estimated equations were: Y(utility) = -0.0161∗X(TSS) + 1.005 in non-asthmatic JCP patients. The ICER of active SLIT to the placebo was estimated to be 4,049,720 and 6,011,218 JPY/QALY in the first and second year, respectively.

CONCLUSIONS

It is possible to reasonably predict utility from the total naso-ocular symptom score by using regression models. In the estimated algorithm, pre-seasonal SLIT for JCP is cost-effective.

Intralymphatic Immunotherapy: Update and Unmet Needs

Allergen-specific immunotherapy (AIT) is the only allergy treatment that confers long-term symptom amelioration for patients suffering from allergy. The most frequently used allergen application route is subcutaneous injection (SCIT), commonly taken as the gold standard, followed by sublingual (SLIT) or oral (OIT) application of allergen preparations. This is an up-to-date review of the clinical evidence for a novel route of allergen application, i.e., directly into lymph nodes - intralymphatic immunotherapy (ILIT). The major advantages of ILIT over the current AIT approaches are its short duration and the low allergen doses administered. The whole treatment consists of merely 3 ultrasound-guided injections into inguinal lymph nodes 1 month apart. While the number of patients included in randomised controlled trials is still limited, the clinical results for ILIT are encouraging, but more clinical trials are needed, as well as more preclinical work for optimising formulations.

Allergen-Specific Immunotherapy for Respiratory Allergy in Children: Unmet Needs and Future Goals

Allergen-specific immunotherapy for the treatment of respiratory allergy is currently supported, at least for selected products, by evidence of efficacy and effectiveness in the pediatric age. However, unmet needs remain in terms of administration regimens, duration of treatment, biomarkers, and preventive effects. These knowledge gaps need to be urgently addressed to provide pediatricians and pediatric allergists with more definite recommendations for the use of this treatment in children. This article critically appraises the most relevant debated issues on allergen-specific immunotherapy in children, focusing on allergen standardization procedures, heterogeneity of clinical studies, and regulatory and pharmacoeconomic aspects.