Applications of Medicines Scoring System (MedSS):
Potential Savings Through Formulary Review of Sulphonylureas
Azuana Ramli1,3, Syed Mohamed Aljunid2 Saperi Sulong2 Faridah Aryani Md Yusof3
1.United Nations University International Institute for Global Health (UNU-IIGH), Kuala Lumpur; 2.International Centre for Casemix and Clinical
Coding (ITCC), Universiti Kebangsaan Malaysia Medical Centre; 3.Pharmaceutical Services Division, Ministry of Health, Malaysia
Introduction
Figure 1: Utility Scores of Sulphonylureas Reviewed Using MedSS
Diabetes is a chronic disease affecting a staggering 15.2% (2.6 million) of adults above
18 years old in Malaysia.1 In 2008, utilization and expenditure of diabetic medicines here
were the highest and second highest respectively among all therapeutic groups.2
Sulphonylureas were the most used anti-diabetics particularly in the public healthcare
setting despite the wider availability of insulin and the newer oral diabetic medicines.2 In
Malaysia available sulphonylureas (SU) include glibenclamide, gliclazide, glimepiride and
glipizide providing varying degree of benefits and risks.3
70.00
Utility Scores
Medicines Formulary system is an accepted mechanism to promote rational prescribing
and manage medicine expenditures.4 In managing the formulary, Medicines Scoring
System (MedSS), a previously developed scoring framework based on multicriteria
decision analysis (MCDA), systematizes medicines evaluation and selection. Through the
framework, selection criteria were chosen and weighted based on the medicines
attributes. Individual medicines were then evaluated and scored objectively against these
criteria based on available evidences and expert group discussions.5
An expert committee of 3 endocrinologists, 1 family physician and 5 pharmacists were
formed. A group of medicine reviewers assisted in evidences search and reviews. In a
series of committee meetings, MedSS scoring framework was applied to evaluate and
score the individual sulphonylureas based on the evidences provided4. The steps were:
1. 
2. 
3. 
4. 
5. 
6. 
Determination of Selection Criteria based on Drug Attributes.
Assignments of Weights to the Selection Criteria
Selection of Comparative Measures and Planning of Utility Scales
Calculation/Assignment of Utility Scores
Calculation on Weighted Utility Scores and Total Utility Scores (TUS) and
Ranking and Sensitivity Analysis
Medicine cost savings was calculated based on the national sulphonylurea utilization
data for the Malaysian Statistics on Medicines 2009/2010 and current median wholesale
prices of the SUs. The current utilization of glibenclamide of about 25% was reduced to
5% with a corresponding increase in gliclazide use, while utilization of glipizide and
glimiperide remains (Model 1). In Model 2, glibenclamide use was also reduced to 5%
while the others (including glipizide and glimepiride) were switched to gliclazide. It was
also assumed that all gliclazide was in its standard (immediate release) form.
Results
Attributes and selection criteria identified and selected by members of expert panel are
listed in Table 1.The average weights assigned by panel members forsafety, efficacy,
patients acceptability and cost were 43.9%, 23.9%, 20.3%, and 11.9%, respectively. The
five sulphonylureas were successfully scored and ranked using MedSS (Figure 1).
Gliclazide in both forms scored consistently high for both efficacy and safety attributes
resulting in total utility score (TUS) of 68.47 and 67.37 for gliclazide modified release (MR)
and gliclazide respectively. Glibenclamide scored high for both efficacy and cost however
safety concerns lowered its TUS to 56.75. When sensitivity analysis was carried out by
varying the allocated weights, both gliclazide forms were consistently ranked at number 1
and 2.
Potential costs savings calculation are presented in Table 2. Based on 2010 medicine
utilization, switching patients to gliclazide could provide annual potential savings of about
RM 2.96 millionto 9.28 million.
Table 1: List of selection criteria and the assigned weights
Attributes
Efficacy
Selection Criteria
Clinical Efficacy
(HbA1C Reduction)
Effects on Clinical Endpoints
(Overall Mortality)
Patient
Acceptability
Economics
Glimepiride
Gliclazide
-10.00
Drug Interactions
3.00
www.PosterPresentations.com
3.4
Hypoglycaemia
13.5
Documentation
2.2
CV Events
9.1
Combination with Insulin
5.7
Other Side Effects
2.2
Use in Specific Population
4.8
Weight Subtotal (Safety)
43.9
Formulations
5.5
Dose frequency
7.5
Weight Change
7.3
Weight Subtotal
(Patient Acceptability)
20.3
Drug Cost
11.9
100.0
Efficacy
Safety
Applicability
Costs
TOTAL
UTILITY
SCORE
(TUS)
13.38
11.14
15.01
15.81
16.40
18.13
26.10
25.67
26.36
28.07
13.96
13.09
16.99
13.50
15.39
11.28
7.14
2.11
11.70
8.62
56.75
57.46
59.78
67.37
68.47
Glibenclamide
Glipizide
Glimepiride
Gliclazide
Gliclazide MR
Gliclazide MR
Table 2: Annual Potential Cost Savings
SU
Glibenclamide
Glipizide
Glimepiride
Gliclazide
TOTAL
SAVINGS (%)
^Utilization
(DDD/1000
population/
day)
*Cost of
Drug
(RM)
/DDD
Proportion
of SU
Utilization
(Current)
8.4364
0.2509
0.5032
25.764
34.9545
0.14
0.56
1.07
0.10
0.241
0.007
0.014
0.737
1.00
Total
Utilization for
whole
#population in
a year (DDD)
88,032,475.74
2,618,101.11
5,250,810.98
268,843,192.00
364,744,579.83
Estimated
Current
Expenditure
for SU per
year (RM)
12,324,546.60
1,466,136.62
5,618,367.75
26,212,211.22
45,621,262.20
Model 1
(Glibenclamide
use reduced to 5%
and others remain)
[RM]
2,571,276.54
1,466,136.62
5,618,367.75
33,004,667.16
42,660,448.07
2,960,814.13 (6.5%)
Model 2
(Glibenclamide use
reduced to 5% and
others switched to
gliclazide) [RM]
2,571,276.54
0
0
33,771,886.09
36,343,162.63
9,278,099.57 (20.3%)
! data collected for Malaysian Statistics on Medicines 2009/2010
^From
*public median wholesale price (MWP): glibenclamide, gliclazide and private MWP: glipizide, glimepiride
# Mid year population in 2010: 28,588,600 was used.
DDD: Defined Daily Dose
SU: Sulphonylureas
Discussion
Decisions made for drug-use policies have great impacts on prescribing practices and
ultimately medicines expenditures. MedSS based on multicriteria decision analysis
principles enabled all the medicine criteria to be systematically selected and weighted
and the medicines utility values be clearly reviewed and scored.
Among the four main attributes considered, the panel members agreed to allocate
higher weight for ‘safety’ due to concerns of hypoglycaemic effects and body weight
changes often reported with SUs use. With good safety and efficacy profiles, gliclazide
scored consistently high. Glibenclamide with poorer safety profiles resulted in lesser
TUS. Overall, gliclazide was singled out as a value-for-money option among the
sulphonylureas reviewed benefiting both patients and healthcare providers. Even
though the two newer SUs, glimepiride and glipizide could match gliclazide in terms of
utilities, the higher costs rendered them unattractive for addition into the formulary.
In the case of highly utilized medicines like sulphonylureas, simple policy reviews such
as promoting prescribers’ switch to cheaper drugs like gliclazide could result in
substantial reductions to the overall medicine expenditures.
Additionally, better overall utilities of gliclazide (indicated by the higher TUS) compared
to glibenclamide, potentially provide savings and benefits beyond monetary values.
Improvement in patient outcomes could ultimately provide greater savings in health
expenditures.
Conclusion
11.1
23.9
TOTAL
TEMPLATE DESIGN © 2007
12.8
Weight Subtotal (Efficacy)
Hazardous side-effects
Safety
Average
Weight
Glipizide
10.00
Objective
Methods
30.00
Glibenclamide
Application of MedSS could also guide formulary reviews and improve medicine use
policy, in turn potentially optimize medicines expenditures.
This study aimed to review the formulary list of sulphonylureas by comparing and ranking
the overall utility values of of the drugs using medicines scoring system (MedSS).5
Potential savings on medicine costs was calculated based on a proposed drug utilization
ratio.
50.00
MedSS successfully organized the attributes and utility values of the medicines
compared. Formularies and medicine use policies based on systematic and evidence
based decision making system like MedSS could also provide substantial savings to
health providers and potentially improve patient outcomes.
Additionally, benefits of clinicians’ involvement in the formulary review using MedSS can
be twofold: better acceptance of any changes planned for the formulary list leads to
improved prescribing pattern hence better management of medicine expenditures.
References
1. Institute for Public Health (IPH) 2011. National Health and Morbidity Survey 2011 (NHMS 2011).
Vol. II: Non- Communicable Diseases.
2. Pharmaceutical Services Division and Clinical Research Centre M of HM. Malaysian Statistics on
Medicines 2008. Kuala Lumpur; 2013:1–176
3. National Pharmaceutical Control Bureau (MOH) at www.bpfk.gov.my
4. Hill-Smith, I. 1996. Sharing resources to create a district drug formulary a countywide controlled
trial. Br J Gen Pract. 46(406): 271-5.
5. Ramli A, Aljunid SM, Sulong S, Md Yusof FA.2013. National Drug Formulary Review of Statins
Therapeutic Group Using Multiattribute Scoring Tool. Therapeutics and Clinical Risk Management
Volume 213 (491-504)
Acknowledgements
The authors wish to thank Dr. Salmah Bahri, Pn. Anis Talib, the specialists involved and the staff of
Pharmaceutical Services Division, Ministry of Health (MOH) for their support, participation and
assistance in this project. We also thank the Malaysian MOH for the permission and funding to
conduct this study ( ID NMRR- 12-77-10772).
ISPOR 6th Asia-Pacific Conference 6-9 September 2014 Beijing