Ranibizumab, verteporfin photodynamic therapy or observation for the treatment of
myopic choroidal neovascularization: cost-effectiveness in the UK
Authors: Lindsay Claxton,1 Bill Malcolm,2 Matthew Taylor,1 Jennifer Haig3, Claudia Leteneux4
Author affiliations:
1York
Health Economics Consortium, University of York, York, UK
Pharmaceuticals UK Limited, Frimley Business Park, Surrey, UK
3Optum, Burlington, Ontario, Canada
4Novartis Pharma AG, Basel, Switzerland
2Novartis
Target journal: Drugs and Aging
Corresponding author:
Lindsay Claxton
York Health Economics Consortium, University of York, York, YO10 5DD, UK
Email: lindsay.claxton@york.ac.uk
Tel: 01904 323620
Fax: 01904 323628
Online Resource 7 Inputs for probabilistic sensitivity analysis
1
Parameter
Mean
SEa
Use of multiplier
Typea
Alpha
Beta
55
15
No
Gamma
13.44
4.09
15.0%
0.5%
No
Lognormal
27
495
6.0%
0.5%
No
Lognormal
37
485
-
Yes (SE: 0.1)
Lognormal
n/a
n/a
As above
-
Yes (SE: 0.1)
Lognormal
n/a
n/a
As above
-
Yes (SE: 0.1)
Lognormal
n/a
n/a
As above
-
Yes (SE: 0.1)
Lognormal
n/a
n/a
General
Starting age
Baseline prevalence of bilateral
myopic CNV
Annual rate of recurrence
Treatment effectiveness
Ranibizumab effectiveness TPs,
M0 to M3
Ranibizumab effectiveness TPs,
M3 to M6
Ranibizumab effectiveness TPs,
M6 to M9
Ranibizumab effectiveness TPs,
M9 to M12
Refer to full
matrices, Online
Resource 1
2
Comparative effectiveness TPs,
As above
-
Yes (SE: 0.1)
Lognormal
n/a
n/a
As above
-
Yes (SE: 0.1)
Lognormal
n/a
n/a
As above
-
Yes (SE: 0.1)
Lognormal
n/a
n/a
As above
-
Yes (SE: 0.1)
Lognormal
n/a
n/a
2.45%
-
Yes (SE: 0.1)
Gamma
400
0.0025
-
Yes (SE: 0.05)
Normal
n/a
n/a
0.1
0.05
No
Normal
n/a
n/a
3.5
-
Yes (SE: 0.05)
Gamma
400
0.0025
1
-
Yes (SE: 0.05)
Gamma
400
0.0025
Treatment visits year 1 (vPDT)
3.4
-
Yes (SE: 0.05)
Gamma
400
0.0025
Treatment visits year 2 (vPDT)
1.7
-
Yes (SE: 0.05)
Gamma
400
0.0025
Monitoring visits year 1
8.5
-
Yes (SE: 0.05)
Gamma
400
0.0025
M0 to M3
Comparative effectiveness TPs,
M3 to M6
Comparative effectiveness TPs,
M6 to M9
Comparative effectiveness TPs,
M9 to M12
Natural deterioration probability
(per 3 months)
Quality of life
Utilities (BSE)
Utilities (WSE relative to BSE)
Refer to
manuscript
Costsb
Treatment visits year 1
(ranibizumab)
Treatment visits year 2
(ranibizumab)
3
(ranibizumab)
Monitoring visits year 2
4
-
Yes (SE: 0.05)
Gamma
400
0.0025
Monitoring visits year 1 (vPDT)
4
-
Yes (SE: 0.05)
Gamma
400
0.0025
Monitoring visits year 2 (vPDT)
4
-
Yes (SE: 0.05)
Gamma
400
0.0025
£17,326
-
Yes (SE: 0.05)
Gamma
400
0.0025
£17,245
-
Yes (SE: 0.05)
Gamma
400
0.0025
(ranibizumab)
Cost of blindness year 1
Cost of blindness subsequent
years
BSE = better-seeing eye; CNV= choroidal neovascularization; NHS = National Health Service; SE = standard error; TP, transition probability; WSE = worse-seeing eye; vPDT
= verteporfin photodynamic therapy.
a If a multiplier was used to vary the base case parameter, the distribution and standard error refers to that around the multiplier rather than the mean value.
b Drug administration costs and follow-up costs were also included in the analysis, using a gamma distribution.
4
Note on the use of multipliers
During the probabilistic sensitivity analyses, many of the parameters, such as transition probabilities,
number of monitoring visits, and costs were varied using a multiplier:

The base case scenario was represented with a multiplier of 1. This was varied in the
probabilistic sensitivity analysis according to the most appropriate probability distribution (with
an assumed standard error) for each parameter.

When the multiplier was used as a risk ratio, the multiplier was varied with a lognormal
distribution.

Multipliers relating to cost, age and patient visit parameters were fitted with gamma
distributions (as these give only non-negative values).

Transition probabilities were varied using a single ‘multiplication factor’ to reflect the
interdependence of transition probabilities:
o
For patients moving to an improved health state, the transition probability was
multiplied by the multiplier
o
For patients moving to a worse health state, the probability was divided by the
multiplier
o
The multiplier was not applied to patients remaining in the same health state
o
To ensure that the total probabilities relating to one health state added to one, each
probability was divided by the sum of the probabilities relating to the health state.
5