Docetaxel with prednisone or prednisolone for the treatment of ...

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Economic review
TABLE 22 Comparison of survival estimates based on within trial analysis and extrapolation approaches
While the mean survival estimate is considered
more appropriate for the purposes of the costeffectiveness
analysis, the difference between these
estimates demonstrates that uncertainty
surrounding the estimates should be appropriately
considered in the final results. No discounting was
applied to these estimates.
Summary of resource utilisation and cost data
Resource utilisation and cost data were estimated
for both the first-line chemotherapy phase and
subsequent costs incurred during the follow-up
period. Resource use data collected alongside the
TAX 327 clinical trial were costed using UK unit
costs in order to estimate average per patient
costs. The costs of drug and administration were
presented separately from other in-trial costs that
were incurred during the first-line chemotherapy
phase (i.e. the costs of managing side-effects) and
those that accrued during the follow-up phase.
Hospitalisations due to the management of sideeffects
were not reported separately from
hospitalisations due to other reasons (e.g.
palliative care). No discounting was applied to
costs.
The drug and administration costs are
summarised in Table 23.
Results from parametric survival analysis Within-trial analysis
Treatment Intercept Scale Mean survival Median survival
(months) (months)
Docetaxel 3.214 0.6482 22.38
(95% CI: 20.38 to 24.62)
18.9
Mitoxantrone 3.036 0.6184 18.65
(95% CI: 17.30 to 20.12)
16.5
Difference 3.73 2.40
TABLE 23 Total costs of first-line chemotherapy phase (drug and administration costs)
Docetaxel (3-weekly regimen) Mitoxantrone
Docetaxel Prednisone Mitoxantrone Prednisone
Dose per cycle (mg/m2 ) 75 10 12 10
Mean body surface area (m 2 ) 1.7 1.7
Total dose per cycle (mg) 127.5 210 20.4 210
Cost per cycle (£) 1023 1.02 169.25 1.02
Total drug cost per cycle (£) 1024 170
Administration cost per cycle (£) 117 117
Mean no. of cycles 7.3 5.9
Total cost (drug and administration) 8329 1695
The total drug and administration costs were
based on the protocol doses stated in TAX 327
(e.g. 75 mg/m 2 for docetaxel and 12 mg/m 2 for
mitoxantrone). This appears to be a conservative
approach since no adjustments were made for
dose reduction for patients experiencing sideeffects
on either chemotherapy regimen. However,
no costs were allocated to the use of
premedication (oral dexamethasone) for patients
receiving the docetaxel 3-weekly regimen. The
exclusion of these costs is unlikely to alter the
results significantly due to the low-acquisition cost
associated with premedication (estimated to be
approximately £5.94 per cycle).
To estimate the total drug costs incurred per cycle,
the protocol doses were adjusted by a mean body
surface area of 1.7 m 2 . No supporting reference
for this body surface area was provided in the
main sponsor submission. After requesting further
clarification from Sanofi-Aventis, this estimate was
stated to be ‘common practice’. In the review of
clinical effectiveness data, only one trial was
identified that reported body surface area. CCI-
NOV22 reported a mean body surface area of
1.9 m 2 in each of the trial arms. This corresponds
exactly to the normal values reported for males in
the general population. 65 Consequently, assuming