A systematic review of the effectiveness of adalimumab

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Appendix 8
TABLE 80 Kobelt et al., 2003 162
Authors Kobelt, Jonsson, Young, Eberhardt
Date 2003
Type of economic evaluation Cost–utility analysis
Country of origin France, Sweden, UK
Currency used Euros, Swedish Kronor, pounds sterling
Year to which costs apply Not stated
Perspective Societal
Study population Patients with RA not responding to at least two DMARDs (including MTX)
Intervention 1 Infliximab + MTX
Intervention 2 MTX alone
Source of effectiveness data Clinical data from two RA cohorts, followed for up to 15 years, in Sweden and the UK
(ERAS), in which average HAQ scores were calculated and used to inform the effectiveness
data and the transition probabilities within the model
Cost data handled Direct costs included hospitalisation, surgical interventions, ambulatory and community care
appropriately and RA medication. Non-medical direct costs and informal care costs were excluded. The
cost of hospitalisation was based on the number of inpatient days in different wards and
ward-specific costs; the cost of surgical interventions was based on the type of intervention
and its duration multiplied by the cost per minute of operating theatre use. Outpatient costs
were based on the number of visits to different healthcare professionals. The cost of RA
drugs was calculated from the number of months of use and the cost associated with
standard drug monitoring protocols in place in the rheumatology departments of
participating study centres. Unit cost data were taken from hospital accounting data and
official price lists. Indirect costs were calculated as the loss of work capacity of patients in the
more advanced disease states. For patients in disease state 1 (i.e. HAQ < 0.6) only shortterm
sick leave was considered. The human capital approach was used, in which an
individual’s productivity is valued at market price. The total number of productive years lost
at each stage (of the model) was compared with the number in state 1, and the difference
multiplied by the average gross annual income. The cost of infliximab was calculated using
the official list price and the doses prescribed in clinical practice (in Sweden and in the UK,
respectively)
Modelling summary Markov model with a cycle length of 1 year (in line with the annual follow-up of
epidemiological studies). A time-horizon of 10 years was used
Outcome measures used in Incremental QALYs (based on EQ-5D) and ICERs
economic evaluations
Direction of result with NE quadrant. For 1 year of treatment, €3440 per QALY in Sweden and €34,800 per QALY
appropriate quadrant location in the UK. The only exception is with the ‘alternative model’ comparing total costs at 1 year
(unadjusted) and total costs at 1 year (adjusted for the effect loss at discontinuation) for
Sweden. The direction of results in these two cases is the SE quadrant (cost saving)
Statistical analysis for Not undertaken
patient-level stochastic data
Appropriateness of statistical NA
analysis
Uncertainty around Not undertaken
cost-effectiveness expressed
Appropriateness of method NA
dealing with uncertainty
around cost effectiveness
Sensitivity analysis A sensitivity analysis was undertaken by way of an ‘alternative model’, in which a loss of
treatment effect was assumed in the year after discontinuation, expressed as a faster disease
progression than that reported in the cohorts. Differences in HAQ scores between infliximab
and MTX groups in the clinical trials were applied to the cohorts for the treatment arm for
the first year. Thus, treatment was compared directly with that of the cohorts. A sensitivity
analysis was also undertaken on the price of infliximab
continued