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

TABLE 19 Percentage of costs by resource category
Inpatient, outpatient and radiation therapy costs
were estimated by applying hotel costs [derived
from the Princess Margaret Hospital (PMH) in
Toronto] to the individual patient level resource
use. The hotel costs covered nursing, laundry,
food and overheads. The cost of physician services
and investigations were estimated from the Ontario
Health Insurance Plan (OHIP) fee schedule. The
acquisition costs associated with chemotherapy
drugs (mitoxantrone) and intravenous antibiotics
were taken from the PMH pharmacy. Other
inpatient drugs were not included as their use was
low. Outpatient drugs were costed via the Ontario
Drug Benefit Formulary. All costs were presented
in terms of 1996 Canadian dollars. No discounting
was applied to costs due to the short nature of the
follow-up.
The individual elements of cost were summated
for each patient to provide patient-level data on
total cost, from which treatment-specific total costs
were estimated. In addition, mean cumulative
costs were presented as a function of time for each
treatment (according to initial randomisation) and
for the patients randomised to and remaining on
prednisone. This allowed investigation of the issue
of crossover within the trial. At an individual
patient level, these plots illustrated a common
pattern with low costs initially followed by a steep
rise towards the end of life. At the treatment level,
the curves were separated but there was no
statistically significant difference in the cumulative
costs over time.
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Health Technology Assessment 2007; Vol. 11: No. 2
Percentage of total cost
Category Mitoxantrone + prednisone Prednisone
Inpatient 53.0 65.8
Outpatient 10.3 8.3
Chemotherapy drug 11.2 5.1
Chemotherapy administration 4.5 2.3
Radiation 4.2 4.3
Analgesic medication 5.0 2.4
Prostate-related drug 4.1 2.8
Diagnostic 3.0 4.0
Blood products 1.0 1.3
Biochemistry 1.2 1.1
Haematology 1.1 1.0
Surgery 0.3 0.6
General drugs 0.3 0.2
Blood-product related 0.3 0.2
Cardiac 0.3 0.1
Antibiotics 0.2 0.2
Microbiology 0.2 0.1
Summary of cost-effectiveness analysis
The results of the cost-effectiveness analysis
were presented in terms of the incremental cost
per QALY gained. The baseline estimate of the
cost-effectiveness indicated that the use of
mitoxantrone plus prednisone dominated
prednisone, with an additional 13.3 qualityadjusted
weeks and a reduced cost of
CAN$1700.
Fieller’s theorem was used to calculate the CI for
the ICER. The upper 95% CI for the ICER was
estimated as CAN$19,700 per QALY gained.
The results for the ICER analysis are reported in
Table 20.
Limited sensitivity analyses were undertaken in
order to assess the robustness of the results to
variation in the costs. A one-way, deterministic
sensitivity analysis was undertaken for the mean
total cost of each category over the following
ranges: inpatient and outpatient costs ±25%,
laboratory and diagnostic costs ±50% and surgery
costs ±500%. Mitoxantrone plus prednisone
remained cost-saving for all of the analyses. A
further one-way sensitivity analysis was undertaken
for the costs in each category, with the total costs
varied within the 95% CI to favour each treatment
individually. Mitoxantrone plus prednisone
remained cost-saving except in the face of
variation in the total cost of inpatient days.
Specific results were not reported.
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