Efficiency of adalimumab, etanercept and infliximab in rheumatoid arthritis patients: dosing patterns and effectiveness in daily clinical practice

OBJECTIVES

This retrospective, multicentre, observational study aimed to assess the mean annual doses and associated costs of three anti-tumour necrosis factor agents in daily clinical practice in rheumatoid arthritis patients, correlating these costs with disease activity.

METHODS

Adult rheumatoid arthritis patients were treated and followed at the Rheumatology departments of two Spanish hospitals for at least 6 months, with adalimumab, etanercept or infliximab over a 4-year period. ANOVA and multivariate statistical analyses of dosing patterns, disease activity and annualised costs were carried out.

RESULTS

A total of 198 patients, comprising 215 cases, met the inclusion criteria (73 on adalimumab, 81 etanercept and 61 infliximab). Compared to recommended doses, mean doses of adalimumab and etanercept decreased by 7% and 19%, respectively, while the mean dose of infliximab increased by 36%. There were no statistical differences between treatments in terms of clinical effectiveness. The hazard of dose escalation was significantly higher for either adalimumab (4.4-fold) or infliximab (11.8-fold) compared to etanercept (p<0.05). Clinical control was achieved and maintained in more than half of the patients treated with reduced doses of etanercept. Associated mean patient-year costs were significantly higher in adalimumab patients (€11.962.58) (etanercept €9.594.73; infliximab €10.094.53; [p<0.05]).

CONCLUSIONS

In rheumatoid arthritis patients, it is possible to reduce doses and associated costs of biological therapies while controlling disease activity. Mean doses used in our clinical practice were significantly lower with etanercept than with the anti-TNF monoclonal antibodies, adalimumab and infliximab. Dose differences impact directly on associated patient-year costs, and thus on treatment efficiency.

Influence on effectiveness of early treatment with anti-TNF therapy in rheumatoid arthritis

PURPOSE

To evaluate the association between starting early treatment with anti-TNF and effectiveness as well as the possibility of applying therapeutic spacing in daily practice in patients with rheumatoid arthritis (RA).

METHODS

Observational, retrospective study conducted in two universitary hospitals in Spain. RA patients who received the first anti-TNF (adalimumab: ADA, etanercept: ETN or infliximab: IFX) during the study period (October 2006-2010) were included. Demographic data, time since diagnosis, disease activity (DAS28-ESR) and anti-TNF dosage were analyzed. Therapeutic objective was defined as DAS28 DAS28 < 2.6. Also the response related to criteria of the European League Against Rheumatism (EULAR) was evaluated. Therapeutic spacing was defined as the use of a lower dose or a higher interval according to label doses. The main endpoint was to assess the association between the effectiveness and the moment when the anti-TNF therapy begins. The secondary target was to evaluate the association between RA activity at the beginning of treatment with anti-TNF and dose used. Results. 82 patients were included. The prescription profile was: ADA (48.8%), ETN (31.7%) and IFX (19.5%). 71.4% of patients treated with anti-TNF during the first year since diagnosis, 57.1% of those who started after 1-5 years and 30.6% of patients who started after 5 years were in remission when the study ended. De-escalation strategy was performed in 25.6% of patients: ETN (38.5%), ADA (20.0%) and IFX (18.8%). The patients treated with a higher dose according to label doses were: IFX (81%), ADA, (12.5%) and ETN (7.7%).

CONCLUSIONS

Results suggest that early treatment with anti-TNF can achieve a higher percentage of remissions. Therapeutic spacing is established as a strategy that improves the efficiency in those patients in remission, being the ETN the anti-TNF most susceptible for spacing, although a relation between the early beginning with anti-TNF and the used dose was not found.