Since receiving a positive recommendation in England, Wales and Scotland, tocilizumab (TCZ) is one of the options available to clinicians for the treatment of rheumatoid arthritis (RA) patients in the UK.
The objective of this study was to evaluate the cost effectiveness of adding TCZ to the current treatment sequence of RA patients from a UK payer's perspective over a patient lifetime horizon.
An individual sampling model was developed to synthesise all clinical and economic inputs. Two scenarios were explored separately: patients contraindicated to methotrexate (MTX) and those MTX tolerant. For each scenario, the analysis compared three strategies. The standard of care (SoC) strategy included a sequence of the most commonly prescribed biologics; the other two comparator strategies considered the addition of TCZ to SoC at first line and second line. Patient characteristics were representative of UK patients. Treatment efficacy and quality-of-life evidence were synthesised from clinical trials and secondary sources. An analysis of a patient registry informed the model parameters regarding treatment discontinuation. The safety profile of all treatments in a given strategy was based on a network meta-analysis and literature review. Resource utilisation, treatment acquisition, administration, monitoring and adverse event treatment costs were considered. All costs reflect 2012 prices. Uncertainty in model parameters was explored by one-way and probabilistic sensitivity analysis.
In the MTX-contraindicated population, if TCZ was added to the SoC in first line, the estimated incremental cost-effectiveness ratio (ICER) was £7,300 per quality-adjusted life-year (QALY) gained; if added in second line, the estimated ICER was £11,400 per QALY. In the MTX-tolerant population, the estimated costs and QALYs of the TCZ strategy were similar to those of the SoC strategy. Sensitivity analysis showed that parameters that affect the treatment cost (such as patient weight) can have a noticeable impact on the overall cost-effectiveness results. The majority of the other sensitivity analyses resulted in modest changes to the ICER.
For the treatment of RA in MTX-tolerant and contraindicated patients, the addition of TCZ to the SoC was estimated to be a cost-effective strategy.