Article Text
Abstract
Background Achieving minimum clinically effective doses could improve the efficiency of treatment with anti-TNF.
Purpose To evaluate the mean dose in ankylosing spondylitis (AS) patients treated with adalimumab (ADA), etanercept (ETN) or infliximab (IFX) in clinical practise and to estimate mean patient-year costs.
Materials and Methods Observational, multicentre, retrospective study performed in two tertiary hospitals. AS patients who received ADA, ETN or IFX from October 2006 to October 2010 were included. Patients could constitute several cases if they received different sequential treatments for at least 6 months. Mean drug consumption was analysed based on individual hospital pharmacy service claims. Demographic data, C-reactive protein (CRP), HLA-B27, axial or mixed AS subtypes, disease activity (BASDAI, BASFI) and concomitant and previous AS treatments were analysed. Associated costs were estimated based on public ex-factory prices including tax (2011 Euros). IFX cost included €110.93 per infusion.
Results 119 patients were included, for a total of 137 cases. No differences were found in recorded variables among groups, except fewer IFX patients (8.2%) had previously received a biological treatment than ETN (25.0%) or ADA (28.6%) patients (p < 0.05).
ANCOVA and multivariate regression analysis showed that the only variable to affect patient-year costs was anti-TNF treatment (table 1).
Conclusions Although IFX patients started with a basal PCR lower than ADA patients and a basal BASFI lower than those treated with ETN, no differences were found among groups at the end of the study. IFX doses were higher than ETN doses as a percentage of the label doses.
No conflict of interest.