Accelerated Dose Escalation with Three Injections of an Aluminum Hydroxide-Adsorbed Allergoid Preparation of Six Grasses Is Safe for Patients with Moderate to Severe Allergic Rhinitis

Only few data on safety during high-dose, accelerated escalation schedules during subcutaneous allergen immunotherapy (AIT) are available. The aim of this study was to assess the safety and tolerability of an accelerated dose escalation schedule of AIT in adult patients with moderate to severe seasonal rhinoconjunctivitis in a multicenter, open-label, randomized phase II trial. The dose escalation scheme for patients in Group I (1 strength) included 3 injections with 1 strength, B (10,000 TU/mL), whereas the dose escalation scheme for Group II (standard) included 7 injections with 2 strengths, A (1,000 TU/mL) and B (10,000 TU/mL), of an aluminum hydroxide-adsorbed allergoid grass pollen preparation. Overall, 72 of 87 randomized patients (83.7%) reported at least 1 treatment-emergent adverse event (TEAE; 82.2 [Group I] vs. 85.4% [Group II]); 58.8% of all reported TEAEs were assessed as being related to AIT (60.0 vs. 48.8%). The most frequently reported AIT-related TEAEs were swelling (46.7 vs. 34.1%), erythema (28.9 vs. 36.6%), and pruritus (31.1 vs. 17.1%) at the site of the injection. Systemic allergic reactions occurred in 5 (5.8%) patients overall, with more being reported in the 1-strength group (4 [8.9%] vs. 1 [2.4%]). All systemic allergic reactions were classified as World Allergy Organization (WAO) Grade 1 or Grade 2 reactions. Accelerated high-dose escalation with an aluminum hydroxide-adsorbed grass pollen allergoid can be initiated with a safety and tolerability profile comparable to the standard dose escalation schedule in patients with allergic rhinitis with or without asthma.