Economic Benefit of Combining Vildagliptin with Insulin
Combination treatment of vildagliptin with insulin is safe and effective. The PBS does not yet support this approach.
Type 2 diabetes patients, on basal insulin (glargine), plus or minus metformin, with either sub-optimal control (HbA1c>7.0%) or intractable obesity, were offered combination treatment with the addition of vildagliptin. Where possible, insulin was discontinued. The amount of insulin saved per patient was calculated and the cost per patient and overall was estimated. There was a net saving, suggesting that there is an economic benefit in the PBS permitting the use of vildagliptin as triple therapy.
Summary of Results:
N = 62 (Male = 33, Female = 29)
Lost = 2
Side-Effects = 4 (GI intolerance = 2, rash = 1, blisters = 1)
Failed treatment = 29
Responders = 27 (12 off insulin; male = 17/27)

Costs:
Glargine: 5 pens, each 3ml glargine, 100units per ml
Box of glargine = $432.75
3ml x 100 units per ml x 5 pens = 1500units
43275 cents/1500 units = 28.85 cents per unit
Vildagliptin: most expensive combined vildagliptin/metformin combination is $100 per 60 tabs $100/60 tabs = 166.667 cents per tab
All patients use 2 tabs per day = 333.3333 cents per day per patient using vildagliptin (any)
27 patients remained on Galvumet = 27 x 333.3333 cents per day
= 8999.99 cents per day is cost of Galvumet

Savings on insulin:
Insulin saved per day = 710 units
Amount saved = 710 units x 28.85 cents per unit = 20483.5 cents per day
Savings on group for 1 day = 20483.5-8999.999 cents = 11485.01 cents per day
Thus savings in insulin cost, after paying for Galvumet used = $114.85 per day

Conclusion: In this group of 62 people, there was a cost saving of per day of $114.85, by combining vildagliptin with insulin. There was an improvement in HbA1c (1.15%), and weight (average weight loss = 0.272727kg).