Cost-effectiveness modelling of biological treatment sequences in moderate to severe rheumatoid arthritis in France.

OBJECTIVES: Modern treatment of RA includes the use of biologics. Their cost is high and comparison between different treatment strategies is needed.

METHOD: Direct medical costs of RA in France were evaluated based on expert opinion. Then, simulation-decision analytical models were developed to assess four biologic treatment sequences over 2 years in patients failing to respond to at least one anti-TNF agent. Effectiveness was expressed in theoretical expected number of days (TEND) in remission or low disease activity [low disease activity score (LDAS)] based on DAS-28 scores.

RESULTS: Direct medical costs of RA in France (excluding the cost of biologics) were estimated at euro 905 (s.d. 263) for 6 months and euro 696 (s.d. 240) for each subsequent 6 months (P < 0.001) for patients achieving LDAS and euro 1215 for 6 months (s.d. 405) for patients not achieving LDAS. Based on LDAS criteria, using abatacept after an inadequate response to the first anti-TNF agent (etanercept) appeared significantly (P < 0.01) more efficacious over a 2-year period (102 TEND) compared with using rituximab at a 6-month re-treatment interval (82 TEND). Mean cost-effectiveness ratios showed significantly lower costs (P < 0.01) per TEND with abatacept as second biologic agent (euro 278) compared with rituximab (euro 303). After an inadequate response to two anti-TNF agents, using abatacept also appeared significantly more efficacious than an anti-TNF agent (P < 0.01). All comparisons were confirmed when using remission criteria instead of LDAS.

CONCLUSION: Advanced simulation models based on clinical evidence and medical practice appear to be a promising approach for comparing cost-effectiveness of biologic strategies in RA.