Interventions:
Some details of the intervention were provided, but the dosage was unclear. The comparator was no biological treatment. There might be other relevant treatment options that could have been included and could have changed the cost-effectiveness results.
Effectiveness/benefits:
The clinical data for the intervention were mainly from a registry, while those for the comparator were from a UK study. The aggregate results from the UK study were used, which means that there could not have been any control for variation in patient characteristics between these cohorts and there was significant potential for bias in the clinical estimates. The authors tested a more conservative rate of change in the HAQ score for the comparator group in the sensitivity analysis, but it was unclear if this was adequate. They assumed that patients reverted to their baseline HAQ score after treatment finished and it was not clear that this was appropriate. They did not report the method used to identify the clinical studies and it was unclear if the best available evidence was used. There appears to have been some uncertainty surrounding the utility estimates, as a correlation between the visual analogue scale and the Disease Activity Score (DAS28) was assumed based on data from a publication.
Costs:
The authors reported the perspective and the relevant cost categories appear to have been included. Some of the costs associated with the intervention were reported, but other direct and indirect costs were poorly reported. For example, little detail was provided on how the lost productivity was calculated. Other adjustments to the cost data, such as discounting, were reported and appear to have been valid.
Analysis and results:
An appropriate incremental analysis was performed and the results were adequately reported and discussed. The uncertainty was investigated in a deterministic sensitivity analyses and best- and worst-case scenarios, but a more thorough investigation would have included a probabilistic sensitivity analysis to explore the uncertainty in all variables simultaneously. The authors discussed some limitations to their analysis.
Concluding remarks:
There were some limitations to the analysis and reporting, which means that the conclusions reached by the authors should be considered with caution.