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Wise et al.

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is incorrect to make a general assumption that “AIT is effective,” since this may lead to the clinical use of products that have not been properly studied. 1614,1616 However, as currently practiced, SCIT has the drawbacks not only of the prolonged period of treatment and multiple visits to health care facilities but also the ever-present risk of systemic reactions. There are now attempts to overcome these limitations by modifying the native allergens or using recombinant technology to produce extracts that are less reactive with sIgE, allowing higher dosing with greater safety and shorter courses of treatment. 1615 (See section IX.D.2. Management – Allergen immunotherapy (AIT) – Modified allergen extracts for additional information on this topic.) Two U.S. healthcare agencies have recently commissioned systematic reviews of the medical literature on the use of AIT in AR 1617,1618 (Table IX.D.3-1). The National Institute for Health Research commissioned an update of the 2007 Cochrane Review of AIT for SAR 1617 and the Agency for Healthcare Research and Quality commissioned a systematic review of the use of SCIT and SLIT for the treatment of AR and bronchial asthma. 1618 The first of these systematic reviews found highly significant differences in favor of SCIT over placebo for improvement of symptoms and medication use for treatment of AR, as well as for improvement in the rhinitis QOL, all with a p value of < 0.00001. 1617 The second systematic review found high-quality evidence for SCIT, compared to placebo, improving rhinitis and rhinoconjunctivitis symptoms and QOL, with moderate quality of evidence for reduction in medication use for treating AR. 1618 A third systematic review using the EBRR methodology found that SCIT for SAR and PAR has Aggregate Grade of Evidence A and recommended SCIT for SAR or PAR patients not responsive to medical therapy, whose symptoms significantly affect QOL. 1619 A search of the EMBASE, MEDLINE, and Cochrane Library databases for systematic reviews and randomized controlled clinical trials yielded a recent otolaryngology clinical practice guideline for AR 761 and an International Consensus on Allergy Immunotherapy 1577,1620 as well as 5 double-blind, placebo-controlled trials of SCIT in AR that were published since the previously discussed systematic reviews (Table IX.D.3-1). All 5 of these trials were conducted with aldehyde-modified natural pollen extracts (allergoids). 1593,1594,1605,1621,1622 These trials all support the efficacy of SCIT in treating AR. Patient selection.: There are 3 therapeutic options for patients with AR: avoidance, pharmacotherapy, and immunotherapy. The evidence supporting avoidance is reviewed in section IX.A. Management – Allergen avoidance . Pharmacotherapy is discussed in section IX.B. Management – Pharmacotherapy . There are 2 primary reasons to consider AIT. 101,1623 One is that addition of AIT to pharmacotherapy alone will likely result in a more pronounced decrease of symptoms (even after a short course of AIT). The second relates to the failure of pharmacotherapy to alter the underlying immunologic process. Patients may choose AIT largely to obtain a lasting benefit, prevent the progression of AR to bronchial asthma, or prevent new sensitizations. 1624-1626 Contraindications for AIT.: The 2015 EAACI Position Paper noted contraindications for instituting SCIT for AR. 1627 Absolute contraindications were poorly controlled or uncontrolled asthma, active autoimmune disorders, and malignant neoplasm. Relative

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Int Forum Allergy Rhinol . Author manuscript; available in PMC 2020 June 10.