A systematic review of the effectiveness of adalimumab

86
Health economics
TABLE 30 Base-case cost-effectiveness results (Schering-Plough)
Population Incremental cost (£) Incremental QALYs ICER
MTX experienced (ATTRACT) 17,370 2.79 6,228
MTX-naïve (ASPIRE) 23,808 1.42 16,766
MTX-naïve with high CRP (ASPIRE) a 23,926 1.84 13,000
a Represent early progressive RA.
stabilisation. ACR20 was used for the stopping
rules in this analysis; however, the stopping rule
recommended by NICE stipulates use of DAS28
scores only. Although the two are related, it is
not clear that ACR20 can substitute for DAS28
changes in practice. Assumptions concerning
the duration of radiographic benefit were shown
to be a possible driver of the cost-effectiveness
results.
Clinical advice recommended that strategies
where dose escalation with infliximab occurred
should be excluded owing to greatly increased
cost while adding very little benefit. The analysis
in this report also does not consider dose
escalation, therefore the ICERs reported for
infliximab will underestimate drug costs. In
reality, dose escalation is common and ideally
should be incorporated in cost-effectiveness
analyses.
Summary of industry submissions
● The submission by Wyeth suggests that
etanercept is highly cost-effective.
● The submission by Schering-Plough suggests
that infliximab is highly cost-effective.
● The submission by Abbott suggests that
adalimumab is highly cost-effective.
● All three submissions report a model-based
cost–utility analysis with a lifetime horizon, and
all three have undertaken extensive sensitivity
analyses. The results of all sensitivity analyses
broadly support the base-case findings of
TABLE 31 TNF inhibitors in late and early RA
support for the use of the new therapy/product
in question.
● Two of the three submissions (those from Wyeth
and Abbott Laboratories) have considered drug
sequences and the use of the new therapy as
part of an existing sequence.
Economic analysis used in this
report
Summary of the Birmingham economic
evaluation
A simulation model, which considered
improvements in quality of life and mortality, but
assumed no effect of the TNF inhibitors on the
need for joint replacement, was used.
For use in accordance with current NICE
guidance, as the third DMARD in a sequence of
DMARDs, the base-case ICER depended on
whether the effectiveness data were taken from
early RA or late RA patients, as shown in Table 31
(in clinical practice there will be a mixture of
both). Sensitivity analyses showed that the results
were most sensitive to figures for HAQ progression
on TNF inhibitors and the effectiveness of
DMARDs, but not particularly sensitive to changes
in mortality ratios used per unit HAQ.
When TNF inhibitors were used as the last active
therapy, the equivalent results were as shown in
Table 32.
Cost per QALY (£) Sensitivity analyses:
late RA data (early RA data) (£)
TNF inhibitor Comparator Late RA Early RA Lowest Highest
Adal (no MTX) Base strategy of 141,000 35,000 41,000 (21,000) Dominated (55,000)
Etan (no MTX) DMARDs with no 47,000 30,000 24,000 (19,000) 95,000 (46,000)
Adal (with MTX) TNF inhibitors 64,000 30,000 30,000 (19,000) 150,000 (43,000)
Etan (with MTX) 50,000 29,000 25,000 (18,000) 96,000 (42,000)
Infl (with MTX) 139,000 30,000 39,000 (19,000) Dominated (45,000)