The Use of Diabetes Drugs in Canadian Public Drug Plans

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The cost of diabetes treatment has been rapidly increasing in Canada in recent years. While the growing prevalence of the disease is a contributing factor, more expensive treatments have been a major cost driver, especially given the uptake in new, higher-cost drugs. This study analyzes these issues from the perspective of Canadian public drug plans, and provides insight into the actual use of the newer and higher-cost diabetes drugs and their associated cost pressures. Results are presented for all public drug plans participating in NPDUIS: British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador, and Health Canada’s Non-Insured Health Benefits drug plan. This analysis will support policy decision makers and the health technology assessment community in determining the future impact of diabetes treatments on their plans.

Key Findings

1. While diabetes drugs account for a sizable and growing segment of the pharmaceutical market in Canada, these trends are even more pronounced in the public drug plans.

With nearly $1.2 billion in sales, diabetes drugs represented 5.7% of the Canadian drug market in 2014/15. The corresponding share in the NPDUIS public drug plans was 8.4%. This represents a marked increase from the 5.1% share in 2010/11.

Section 1

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Section 1

Figure description

This bar graph and accompanying table give the diabetes share of pharmaceutical expenditures from fiscal year 2010/11 to 2014/15.

The bar graph has two entries for each year. The first gives the share of national retail sales as a percentage of pharmaceutical expenditures, and the second bar gives the share of the NPDUIS public plan costs.

National retail sales: 2010/11, 3.8%; 2011/12, 4.2%; 2012/13, 4.7%; 2013/14, 5.3%; 2014/15, 5.7%.

NPDUIS public plans: 2010/11, 5.1%; 2011/12, 5.6%; 2012/13, 6.7%; 2013/14, 7.5%; 2014/15, 8.4%.

The accompanying table gives the actual share of sales in millions of dollars.

National retail sales: 2010/11, $759; 2011/12, $821; 2012/13, $924; 2013/14, $1,034; 2014/15, $1,163.

NPDUIS public plans: 2010/11, $290; 2011/12, $335; 2012/13, $398; 2013/14, $457; 2014/15, $514.

2. The rapid growth in diabetes drug costs in public drug plans has outpaced overall drug cost growth.

While the rate of change in the cost for all drugs has been low or dipping into negative ranges in recent years, generally due to savings from generic drugs, the diabetes market segment has had a sustained double-digit rate of growth, averaging 17% annually from 2010/11 to 2014/15.

Section 2

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Section 2

Figure description

This bar graph gives the annual rates of growth in costs for all drugs compared to those for diabetes drugs from fiscal year 2011/12 to 2014/15.

All drugs: 2011/12, 0.3%; 2012/13, -1.5%; 2013/14, 2.0%, 2014/15, 2.3%.

Diabetes drugs: 2011/12, 16%; 2012/13, 19%; 2013/14, 15%, 2014/15, 13%.

3. Diabetes in public plans: more patients, more prescriptions, and more high-cost drugs.

Between 2010/11 and 2014/15, diabetes drug costs increased in NPDUIS public drug plans by 76%. Of this overall growth:

  • 22% was due to an increase in the number of diabetes patients;
  • 19% was due to each patient having more prescriptions for diabetes drugs; and
  • 35% was due to an increased cost per prescription, as higher-cost diabetes drugs were increasingly used.
Section 3

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Section 3

Figure description

A single bar graphically illustrates the impact of the drivers of the growth in diabetes drug costs from 2010/11 to 2014/15. Of the 76% growth in costs over this time period, 22% resulted from an increase in the number of patients and 54% resulted from increased treatment costs. Treatment costs include a 19% increase in the volume of prescriptions and a 35% increase in the cost per prescription.

4. Diabetes treatment costs on the rise in recent years.

While insulins dominate the treatment cost, dipeptidyl peptidase-4 (DPP-4) inhibitors represent an emerging market segment.

The cost to treat 1,000 diabetes patients grew from $294,550 in 2010/11 to $436,754 in 2014/15. A drug-level analysis suggests that much of the growth was driven by the increased use of newer, more expensive long-acting insulins (e.g., Lantus and Levemir) and a new class of drugs, DPP-4s.

Section 4

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Section 4

Figure description

This area plotted graph gives the average diabetes treatment cost per 1,000 beneficiaries from fiscal year 2010/11 to 2014/15.

2010/11 2011/12 2012/13 2013/14 2014/15
Other antiglycemics $7,301 $4,984 $4,014 $3,524 $3,242
Thiazolidinediones $41,711 $25,126 $13,208 $7,713 $5,021
Sulfonylureas $23,892 $24,440 $23,911 $23,180 $22,155
DPP-4s $15,361 $46,445 $70,721 $90,390 $102,444
Metformin $62,475 $59,507 $69,655 $76,665 $85,855
Insulins $143,810 $161,966 $185,974 $203,083 $218,037

5. Newer, high-cost long-acting insulins and DPP-4s have been the main drivers of diabetes costs in public plans.

Alone, these drugs have had an important push effect on diabetes drug costs, ranging from 19% in 2011/12 to 9% in 2014/15. Note that these results are dominated by the impact on the Ontario public drug plans given the size of this market.

There has been a reduction in the use of thiazolidinediones (Actos and Avandia) due to safety concerns. While this reduction has had a pull effect on diabetes costs, it was offset by an increase in other diabetes treatment options.

Section 5

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Section 5

Figure description

This illustration consists of a bar graph depicting the contribution of each subgroup of diabetes drug to the growth in cost from fiscal year 2011/12 to 2014/15.

Diabetes drug 2011/12 2012/13 2013/14 2014/15
Long-acting insulin 6.95% 8.64% 6.38% 4.85%
Other insulins 2.56% 1.54% 0.78% 1.35%
Metformin 0.01% 4.02% 2.94% 3.20%
DPP-4s 11.51% 8.20% 6.17% 3.88%
Sulfonylureas 0.60% 0.09% 0.05% -0.03%
Thiazolidinediones -4.95% -3.29% -1.30% -0.57%
Other antiglycemics -0.64% -0.23% -0.08% -0.03%

The accompanying table gives the average cost per prescription for each subgroup of drugs.

Diabetes drug Average cost per prescription 2014/15
Long-acting insulin $159
Other insulins $85
Metformin $15
DPP-4s $87
Sulfonylureas $9
Thiazolidinediones $58
Other antiglycemics $23

6. Many diabetes patients use a combination therapy, with insulin and oral agents to manage hyperglycemia.

The Canadian Agency for Drugs and Technologies in Health’s optimal therapy recommendations for 2nd and 3rd line therapies suggest the use of NPH insulin (an intermediate-acting insulin) when metformin and sulfonylurea are inadequate to control hyperglycemia. DPP-4s are recommended only when insulin is not an option. This analysis found that 20% of publically covered patients in Ontario used DPP-4s and insulins in the same year. The jurisdictional variations may be due to plan design and formulary listing decisions.

Section 6

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Section 6

Figure description

This bar graph depicts the share of patients on combination therapy with insulins for three public drug plans in fiscal year 2014/15 by drug group.

NIHB: DPP-4s, 10%; sulfonylureas, 23%; metformin, 61%.

Saskatchewan: DPP-4s, 5%; sulfonylureas, 16%; metformin, 52%.

Ontario: DPP-4s, 20%; sulfonylureas, 21%; metformin, 57%.

Data Sources: *NPDUIS Database, Canadian Institute for Health Information. † MIDAS™ Database, Retail Sector, Manufacturer Ex-factory Sales, IMS AG. All Rights Reserved.

Limitation: The results presented do not reflect pricing negotiated through confidential Product Listing Agreements.

Time period: Fiscal years 2010/11 to 2014/15.

Disclaimer: Although based in part on data obtained from Canadian Institute for Health Information or provided under license by the IMS AG’s MIDAS™ Database, the statements, findings, conclusions, views and opinions expressed in this report are exclusively those of the PMPRB and are not attributable to either the Canadian Institute.

NPDUIS is a research initiative that operates independently of the regulatory activities of the PMPRB.

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