Dropouts From Sublingual Immunotherapy and the Transition to Subcutaneous Immunotherapy in House Dust Mite-Sensitized Allergic Rhinitis Patients

Abstract

Purpose: Both subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are effective in reducing symptoms and medication scores and inducing long-term efficacy in patients with allergic rhinitis (AR). However, SLIT has been associated with poor patient adherence. This study investigates the factors impacting dropout rates from SLIT in house dust mite (HDM)-sensitized AR patients.Methods: A retrospective study was performed to analyze dropout rates and reasons in AR patients receiving Dermatophagoides farinae (Der f) SLIT with a follow-up period of 2 years.Results: A total of 719 HDM-sensitized AR patients received Der f-SLIT. Dropout rates increased with time and most occurred after 1 year of SLIT. By month 24, 654 (91%) patients had discontinued SLIT. The dropout rates by month 24 were 100, 90.1, and 91.1% in children <5 years old, children aged 5–18 years old, and adults ≥ 18 years old, respectively. Combination with allergic asthma and mono- or multi-sensitization to other aeroallergens did not affect the dropout rates. The most common self-reported reasons for dropouts were refusal of continuation, dissatisfaction with the efficacy, transition to SCIT, and adverse effects. Refusal of continuation increased with age, whereas transition to SCIT decreased with age. Ninety-seven cases transitioned from SLIT to SCIT, and the transition rates increased with time. Comorbid allergic asthma did not affect the transition rates. However, multi-sensitization was associated with a slightly higher rate of transition to SCIT. The most common reason for the transition was dissatisfaction with the efficacy (54.6%), which was only reported by patients older than 5 years. For children who began SLIT at younger than 5 years old, the most common reason (81.2%) for transition was age reaching 5 years.Conclusions: HDM-SLIT has a very high dropout rate, which is mainly due to refusal of continuation and dissatisfaction with the efficacy. Transitioning from SLIT to SCIT may help keep these patients on AIT and thus increase adherence and long-term efficacy.

Update on pathomechanisms and treatments in allergic rhinitis

“…Shorter up‐dosing schedules such as 7‐injection or 11‐injection schedules have also been developed 98 . Comparative studies between the SCIT and SLIT in terms of effectiveness, safety, and cost‐effectiveness are limited, and the results are difficult to interpret 99–101 . Shamji et al 102 have indicated that blocking the activity of the IgE–allergen complex binding to B cells had similar effects to SLIT and SCIT, while specific IgA production was increased after SLIT and IgG4 production was increased following SCIT.…”

“…98 Comparative studies between the SCIT and SLIT in terms of effectiveness, safety, and cost-effectiveness are limited, and the results are difficult to interpret. [99][100][101] Shamji et al 102 have indicated that blocking the activity of the IgE-allergen complex binding to B cells had similar effects to SLIT and SCIT, while specific IgA production was increased after SLIT and IgG4 production was increased following SCIT. Thus, more head-to-head studies are needed to investigate the differences between SLIT and SCIT, which may aid in selection of a personalized therapy method.…”

Short‐course subcutaneous treatment with PQ Grass strongly improves symptom and medication scores in grass allergy

“…10 Moreover, a modified short-course SCIT of only six pre-seasonal injections has the potential to address the high noncompliance rates reported tablet/drop SLIT formulations, in which adherence in clinical practice is generally poor, with a recent study showed that up to 91% of patients stop prematurely during 2 years of treatment. 11 PQ Grass is developed as a short-course (six pre-seasonal injections) modified SCIT product containing an extract of 13 different grass pollens. The native aqueous extract is chemically modified with glutaraldehyde cross-linking approximately 85% of epsilon-amino lysine groups producing a polymeric allergoid (active ingredient).…”

“…Although SCIT is associated with a higher risk of allergic adverse events (AEs) than sublingual immunotherapy (SLIT), chemical modification of allergens may improve SCIT safety pattern by reducing allergenicity via disruption of IgE reactive epitopes and maintaining immunogenicity via retention of IgG reactive epitopes, 9 thus achieving a safety profile comparable to SLIT 10 . Moreover, a modified short‐course SCIT of only six pre‐seasonal injections has the potential to address the high noncompliance rates reported tablet/drop SLIT formulations, in which adherence in clinical practice is generally poor, with a recent study showed that up to 91% of patients stop prematurely during 2 years of treatment 11 …”