Methods: Two products for the treatment of grass pollen induced ARC were investigated: a SCIT treatment (Alutard SQ, Phleum pratense, 100,000 SQ-U/ml) and an AIT treatment (Grazax, Phleum pratense 75,000 SQ-T/2,800 BAU), ALK, Denmark).
Data were drawn from the Prescribed Drug Registry 2007-2009, the National Board of Health and Welfare in Sweden. Data on patients treated and number of packages sold were used to calculate the compliance and persistence for each of the 2 products, for patients who started treatment in 2007.
Compliance: calculated as the duration of treatment estimated from the number of packages sold (assuming 100% compliance), divided by the actual duration of treatment (the time estimated from the first to the last observed prescription, plus the duration of the last package). Persistence: calculated as the percentage of patients who continued their treatment in 2009 with at least initiation of 1 treatment package or vial in 2009.
Results: Grass AIT treatment was started by 636 patients and the grass SCIT treatment by 354 patients in 2007. The persistence of treatment in 2009 was 55% for grass AIT treatment and 57% for grass SCIT treatment.
The estimated average duration of treatment was 2.34 years for grass AIT and 2.47 for grass SCIT at cut-off 31 December 2009. The average number of tablets used per patient during this period was 770. For grass SCIT treatment the average number of up-dosing kits used was 1.07 and the average number of maintenance vials was 3.26 (5 injections per vial). This corresponded to a compliance of 90% for grass AIT and 82% for grass SCIT.
Conclusions: Compliance to treatment for grass AIT and grass SCIT treatments were both high (>80%) and comparable. The persistence of Swedish patients was comparable for grass AIT and grass SCIT treatments during the period 2007 to 2009.