RESUMO
BACKGROUND: Early pollen flight and new allergens prolonging the pollen season means that the time for up-dosing of allergen-specific subcutaneous immunotherapy (SCIT) outside the pollen season becomes shorter. Hence, for patients who wish or need to be up-dosed faster, an accelerated induction regimen would provide a useful treatment option. METHODS: An accelerated up-dosing regimen (0.1-0.3-0.5 mL at weekly intervals) was compared to conventional up-dosing (0.05-0.1-0.2-0.3-0.4-0.5 mL at weekly intervals) using an allergoid birch pollen SCIT preparation. After up-dosing, the maintenance dose (0.5 mL) was given 3 times at biweekly intervals. The multicenter study was performed according to an open randomized, parallel-group design. RESULTS: A total of 123 birch pollen-allergic patients (81 adults and 42 adolescents) presenting with rhinitis or rhinoconjunctivitis with or without mild asthma (FEV1 >70%) were randomized to either the conventional registered up-dosing or an accelerated regimen. In total, 96.7 and 98.4% successfully reached the maintenance dose for the conventional and accelerated regimen, respectively, without relevant differences between adults and adolescents. Both regimens were safe and well tolerated. Furthermore, significant increases (similar in size) in specific IgG and IgG4 after 3 months of treatment were observed in both groups, independent of age. CONCLUSION: The accelerated SCIT regimen was revealed to be as safe as the conventional regimen, and the immunological effects of both regimens are similar. Accordingly, the accelerated regimen may be used to up-dose patients of adult as well adolescent age within 2 weeks.