A systematic review and economic model of the effectiveness and ...

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Review of economic evaluations of ADHD drug interventions in children and adolescents
TABLE 78 Two-way sensitivity analysis of morning and lunchtime compliance rates in secondary analysis of the cost–utility model
submitted by Celltech
TABLE 79 Subgroups considered in the cost–utility model submitted by Eli Lilly
Subgroup Description
Lunchtime compliance (%)
Time horizon
The model employed a time horizon of 1 year,
which excludes consideration of the longer term
outcomes associated with ADHD and its treatment.
Compliance
The main difference between treatments is the
assumed levels of compliance to morning and
afternoon doses of medication. Unfortunately, this
information was based on expert opinion using an
estimate of overall compliance and a two-way
sensitivity analysis showed that the results were
very sensitive to the assumption made. The
submission also fails to justify why compliant nonresponders
would be identified and moved to an
alternative treatment, but non-compliers, who by
definition fail to respond, would not be identified
as non-responders.
Review of the Eli Lilly submission
The electronic model to accompany the Eli Lilly
submission was not examined owing to its late
ICER for Equasym XL compared to IR-MPH (£)
Morning
compliance
(%) 50 55 60 65 70 75 80 85 90 95
50 –90,012 –45,925 –31,229 –23,882 –19,473 –16,534 –14,435 –12,860 –11,635
55 84,780 –88,457 –45,148 –30,711 –23,493 –19,162 –16,275 –14,212 –12,666
60 40,694 83,226 –86,902 –44,370 –30,193 –23,104 –18,851 –16,016 –13,990
65 25,998 39,916 81,671 –85,348 –43,593 –29,675 –22,716 –18,540 –15,757
70 18,650 25,480 39,139 80,116 –83,793 –42,816 –29,156 –22,327 –18,229
75 14,242 18,262 24,962 38,362 78,561 –82,238 –42,038 –28,638 –21,938
80 11,302 13,931 17,873 24,443 37,584 77,007 –80,683 –41,261 –28,120
85 9,203 11,043 13,620 17,484 23,925 36,807 75,452 –79,128 –40,483
90 7,629 8,981 10,784 13,309 17,096 23,407 36,029 73,897 –77,574
95 6,404 7,434 8,759 10,525 12,998 16,707 22,889 35,252 72,342
1 Stimulant-naïve patients with no contraindications to any treatment option
2 Stimulant-naïve patients with contraindications to stimulants (MPH and DEX)
3 Stimulant-exposed patients who have previously failed on MPH therapy owing to adverse events or
inefficacy
4 Stimulant-exposed patients with contraindications to stimulants (MPH and DEX)
5 Stimulant-exposed patients who have no contraindications to any treatment option, and who have not
failed on previous therapy for either adverse events or inefficacy
submission. Therefore, this review reports the
model structure, inputs and results as reported by
Eli Lilly, but these values could not be validated by
examination of the model.
Overview
The submission states that a Markov model was
used to examine the cost-effectiveness of adding
ATX to an existing strategy of medical
management for ADHD. The underlying general
strategy was that a new patient would be given an
MPH formulation first-line, followed by DEX as a
second-line alternative in the event of treatment
discontinuation, followed by no treatment. ATX
was added as an additional treatment option prior
to MPH. The model considered five subgroups
with varying ineligibility for one or more of the
treatment options. Table 79 details the subgroups
considered in the model.
For groups 1 and 5, the treatment strategies
compared are IR-MPH or ER-MPH, followed by
DEX, followed by no treatment, with or without
ATX prior to MPH. For groups 2 and 4, the