A review of clinical efficacy, safety, new developments and adherence to allergen-specific immunotherapy in patients with allergic rhinitis caused by allergy to ragweed pollen (Ambrosia artemisiifolia)

Adherence and persistence in allergen immunotherapy (APAIT): A reporting checklist for retrospective studies

BACKGROUND

Adherence is essential for the long-term efficacy of allergen immunotherapy (AIT) and has been evaluated in numerous retrospective studies. However, there are no published guidelines for best practice in measuring and reporting adherence or persistence to AIT, which has resulted in substantial heterogeneity among existing studies. The 'adherence and persistence in AIT (APAIT)' checklist has been developed to guide the reporting, design and interpretation of retrospective studies that evaluate adherence or persistence to AIT in clinical practice.

METHODS

Five existing checklists, focussing on study protocol design, the use of retrospective databases/patient registries, and the appraisal and reporting of observational studies, were identified and merged. Relevant items were selected and tailored to be specific to AIT. The content of the checklist was discussed by 11 experts from Europe, the United States and Canada, representing allergy, healthcare and life sciences, and health technology appraisal.

RESULTS

The APAIT checklist presents a set of items that should either be included or at least considered, when reporting retrospective studies that assess adherence or persistence to AIT. Items are organized into four categories comprising study objective, design and methods, data analysis, and results and discussion. The checklist highlights the need for clarity and transparency in reporting and emphasizes the importance of considering potential sources of bias in retrospective studies evaluating adherence or persistence to AIT.

CONCLUSIONS

The APAIT checklist provides a pragmatic guide for reporting retrospective adherence and persistence studies in AIT. Importantly, it identifies potential sources of bias and discusses how these influence outcomes.

Adherence in allergen immunotherapy: Current situation and future implications

Allergen immunotherapy (AIT) is the only disease-modifying treatment in allergy. However clinical trials as well as real-life studies revealed poor treatment adherence. This article is intended to provide an overview of the current literature of the last 10 years, to outline reasons for poor treatment adherence in AIT and to provide possible solutions for improving adherence.

Effects of rAmb a 1-Loaded PLGA-PEG Nanoparticles in a Murine Model of Allergic Conjunctivitis

Ambrosia artemisiifolia (Amb a) contains many allergens. Allergic conjunctivitis caused by Ambrosia artemisiifolia and its related allergen-specific immunotherapy (AIT) are seldom studied at present. poly(DL-lactide-co-glycolide)-polyethylene glycol (PLGA-PEG) is a very good nano-carrier, which has been applied in the medical field. In this context, we studied the immunotherapy effect and potential mechanism of recombinant Amb a 1 (rAmb a 1)-loaded PLGA-PEG nanoparticles. A mouse allergic conjunctivitis model was established with Ambrosia artemisiifolia crude extract, and the nanoparticles were used for AIT through direct observation of conjunctival tissue, degranulation of mast cells in conjunctival tissue, serum-specific antibodies, cytokines and other assessment models. The treatment of nanoparticles enhanced the secretion of T-helper 1 (Th1) cytokine Interferon-gama (IFN-γ) and the production of immunoglobulin G (IgG)2a (IgG2a), inhibited the secretion of T-helper 2 (Th2) cytokine Interleukin (IL)-13 and IL-4 and the level of IgE. Especially, degranulation of mast cells and expression of mast cell protease-1 (MCP-1) in conjunctival tissue was reduced significantly. In this study, we proved that the nanoparticles prepared by rAmb a 1 and PLGA-PEG have an immunotherapy effect on allergic conjunctivitis in mice.

30 years of sublingual immunotherapy

Allergen Immunotherapy (AIT) was introduced in clinical practice on an empirical basis more than 100 years ago. Since the first attempts, AIT was administered subcutaneously. Indeed, other routes of administration were proposed and studied, in particular to improve the safety, but only the sublingual route (SLIT) achieved a credibility based on evidence and was then accepted as a viable "alternative" option to the subcutaneous route. SLIT was largely used in clinical trials and clinical practice in this last 30 years. Thus, a large amount of data is available, coming from either controlled trials and postmarketing surveillance studies. It is clear that SLIT is overall effective, but it is also clear that the efficacy is not "class-related," as derived from meta-analyses, but restricted to each specific product. The 30-year lasting use of SLIT allowed to clarify many clinical aspects, such as efficacy, safety, use in asthma, regimens of administration, and optimal doses. In parallel, the mechanisms of action of AIT were elucidated, and new indications were proposed (eg food allergy, atopic dermatitis). In addition, the introduction of molecular-based diagnosis, allowed to better refine the prescription of SLIT, based on specific sensitization profiles. The present article will describe the origin and evolution of SLIT for respiratory allergy, taking into account the clinical context that suggested this form of treatment, the recently developed aspects, the future perspectives and unmet needs, This is not, therefore, a systematic review, rather a narrative historical description of the past history, and a look forward to the future opportunities.

New modalities of allergen immunotherapy

Allergen immunotherapy is a rapidly evolving field. Although subcutaneous immunotherapy has been practiced for over a hundred years, improved understanding of the underlying immunological mechanisms has led to the development of new, efficacious and better tolerated allergen-derivatives, adjuvants and encapsulated allergens. Diverse routes of allergen immunotherapy - oral, sublingual, epicutanoeus and intralymphatic - are enabling immunotherapy for anaphylactic food allergies and pollen-food allergy syndrome, while improving the tolerability and effectiveness of aeroallergen immunotherapy. The addition of Anti-IgE therapy decreases adverse effects of subcutaneous and oral immunotherapy.