Safety and Tolerability of an Intra-seasonal Initiation of the SQ-Standardised Grass Allergy Immunotherapy Tablet: A Non-interventional Observational Study Investigating the Feasibility During Routine Administration

Background: For specific immunotherapy to pollen allergy, a pre-seasonal start of treatment is recommended by international guidelines. In a placebo-controlled clinical trial with adults, an intra-seasonal start of therapy with the SQ-standardised grass allergy immunotherapy tablet (AIT) was well-tolerated. The objective of our study was to investigate the feasibility of an intra-seasonal start of grass AIT administered during routine treatment by practising allergists. Methods: In a multicentre, prospective, open-label, uncontrolled, non-interventional observational study, data on routine treatment with grass AIT were recorded in patients who started administration of tablets within the 2010 grass pollen season in Germany. Adverse events (AEs) were recorded by the physician at visits for the first administration in the clinic and at the end of the 1- to 3-month observation period. AEs and daily administration of the tablet were recorded by the patients in diaries for the first 14 days. Treatment satisfaction, global tolerability and perceived effect of treatment were assessed by the patient and physician at the end of the study. Results: A total of 662 patients were treated with 1 tablet daily by 286 physicians. Grass AIT was started intra-seasonally in 620 patients and post-season in 42. The average treatment period was 51.6 days. AEs were recorded in 52.1 % of all patients and in 35.6 % at first administration, with throat irritation (21.3 %), paraesthesia oral (19.9 %), oral pruritus (14.0 %) and ear pruritus (10.3 %) being the most frequent AEs related to grass AIT. The intensity of the AEs was assessed as mild or moderate in 42.1 % of patients and severe in 8.0 %; AEs related to grass AIT were classified as serious in two patients. Grass AIT was discontinued due to AEs in 7.7 % of patients. Diaries were evaluable for 77.0 % of patients; the average rate of patients with AEs decreased continuously from 44.7 % (day 1) to 26.9 % (day 14) and the average daily rate of patients who forgot to take their tablet was about 5 %. Overall tolerability was assessed by 87.2 % of patients and 91.4 % physicians as "very good" or "good" and effectiveness of treatment was assessed as "very good" or "good" in 81.4 % of patients and 85.8 % of physicians. More than 90 % of patients and physicians were satisfied with the treatment. Conclusion: The tolerability data for an intra-seasonal start of grass AIT during routine treatment confirm the safety profile from the previous controlled trial. Tolerability was assessed as good in combination with high satisfaction with the treatment and compliance.