Economic evaluation of specific immunotherapy versus symptomatic treatment of allergic rhinitis in Germany

To use published data to compare the economic consequences of specific immunotherapy (SIT) lasting 3 years with those of continuous symptomatic treatment in patients with either pollen or mite allergy.

The evaluation was conducted from the following 3 perspectives in Germany: (i) society; (ii) healthcare system; and (iii) statutory health insurance (SHI) provider. A modelling approach was used which was based on secondary analysis of existing data. The follow-up period was 10 years. The break-even point of cumulated costs, their difference per patient and the additional cost per additional patient free from asthma symptoms [incremental cost-effectiveness ratio (ICER)] were used as target variables, each from the viewpoint of SIT. The types of costs were direct and indirect (society), direct (healthcare system) and those incurred by SHI (i.e. expenses). In the base-case analysis, the average values of the clinical parameters and average case-related costs/expenses were applied.

The break-even point was reached between year 6 and year 8 after the start of therapy, resulting in net savings of between 650 and 1190 deutschmarks (DM) per patient after 10 years. The ICERs of SIT were between -DM3640 and -DM7410, depending on study perspective and nature of the allergy (1990 values for symptomatic treatment and treatment of asthma, 1995 values for SIT; DM1 approximately $US0.58). The sensitivity analysis demonstrated the robustness of the model and its results. First, all the independent variables of the model were varied. Secondly, the influence of the model variables was quantified using a deterministic model. SIT was more likely to result in net savings than in additional costs. An economic parameter (cost for symptomatic treatment) had the highest influence on the results.

This evaluation showed that SIT for 3 years is economically advantageous in patients who are allergic to pollen or mites and whose symptoms are inadequately controlled by continuous symptomatic treatment. After 10 years, the administration of SIT leads to net savings from the perspectives of society, the healthcare system and SHI (third-party payer) in Germany.