Adherence to immunotherapy in times of financial crisis

Long-term adherence strategies for allergen immunotherapy

Adherence is crucial for allergen immunotherapy (AIT) efficacy, and a long-term 3-year adherence is indispensable for the long-term benefits beyond AIT administration. Nonadherence causes should be analyzed not only at the patient level but from a broader perspective, including socioeconomic factors, health-care system factors, and disorder- and therapy-related factors. Subcutaneous immunotherapy (SCIT) adherence is ∼50% at best and, for sublingual immunotherapy, the numbers are even much worse in some regions. In this review, causes for AIT loss of adherence and strategies, published and from personal experience, to reduce nonadherence are presented. Although the broader picture of causes of nonadherence has to be taken into account, in all this, the patient-physician and patient-health care professional (AIT nurse, assistant) are still in the center, and, in SCIT, each clinic visit for a shot is an opportunity to exploit this interaction in a positive way and stimulate adherence. Patient factors of nonadherence are not so much forgetfulness but more perception of ineffectiveness and adverse effects. An explanation of what can be expected before starting AIT is crucial because most of those who drop out are seen during the first year. Adherence is especially under risk when administration is temporarily interrupted (lockdown, illness, disease flare, vacation, preseasonal AIT administration schedules). The pandemic has caused higher rates of nonadherence specifically due to a fear of getting infected with severe acute respiratory syndrome coronavirus 2, which can be mitigated with good hygiene techniques and strict sanitization protocols, which ensure the patients. Also, patient mobile discussion networks related to AIT can help encourage adherence and reduce fear of infection, even in these difficult times.

Selection of patients for sublingual versus subcutaneous immunotherapy

Allergen immunotherapy is the sole treatment for IgE-mediated allergic diseases directed at the underlying mechanism. The two widely accepted administration routes are sublingual (SLIT) and subcutaneous (SCIT). We reviewed how patients should best be selected for immunotherapy and how the optimal administration route can be defined. Before deciding SCIT or SLIT, appropriate selection of patients for allergen immunotherapy (AIT) is mandatory. To be eligible for AIT, subjects must have a clear medical history of allergic disease, with exacerbation of symptoms on exposure to one or more allergens and a corresponding positive skin or in vitro test. Then the route of administration should be based on: published evidence of clinical and immunologic efficacy (which varies per allergic disease and per allergen); mono- or multi-allergen immunotherapy, for SLIT multi-allergen immunotherapy was not effective; safety: adverse events with SLIT are more frequent, but less severe; and, costs and patient preferences, closely related to adherence issues. All these are discussed in the article.

Current status of sublingual immunotherapy in the United States

Sublingual immunotherapy (SLIT) use in the United States to date has been limited, despite common use and demonstrated efficacy elsewhere in the world. This is largely in part due to lack of FDA-approved SLIT products, lack of established dosing and administration guidelines, and cost concerns. Several recent studies have demonstrated efficacy and safety of two sublingual grass tablets and one ragweed tablet approved by the FDA, and one sublingual ragweed liquid currently pending FDA approval. With FDA approved SLIT products, there will be numerous challenges to the allergist and patient in deciding whether to pursue SLIT or SCIT (subcutaneous immunotherapy) for allergic rhinitis. This review highlights the current state of SLIT in the United States, and expected future directions.