Saxagliptin non-inferior to glipizide in Type 2 diabetes
MedWire News: For patients with Type 2 diabetes who show inadequate glycemic control on metformin alone, add-on therapy with saxagliptin achieves equivalent reductions in glycated hemoglobin (HbA1c) as standard glipizide, results of a non-inferiority trial show.
Furthermore, patients in the saxagliptin group experienced significantly fewer hypoglycemic and other adverse events than the control group.
"Failure to achieve and maintain adequate glycemic control is caused by the progressive nature of Type 2 diabetes mellitus and the limitations of current therapies," Ingrid Gause-Nilsson (AstraZeneca R&D, Mölndal, Sweden) and colleagues comment in the International Journal of Clinical Practice.
Metformin is standard first-line pharmacotherapy for patients with Type 2 diabetes, but it is often insufficient to maintain glycemic goals over time.
Sulphonylureas, including glipizide, are commonly used as add-on therapy; however, their use is associated with limitations including multiple titration steps, the potential for beta-cell failure, weight gain, and increased risk for hypoglycemia.
Dipeptidyl peptidase-4 inhibitors, of which saxagliptin is one, are a relatively new class of oral antidiabetic drugs, and may offer a more favorable alternative to sulphonylureas.
To investigate, the researchers recruited 858 patients on stable metformin doses (≥1500 mg/day) who were randomly assigned to receive saxagliptin (5 mg/day) or glipizide up-titrated as needed from 5 to 20 mg/day, for 52 weeks.
Elevation in HbA1c from baseline was not significantly different between the two arms, at 0.74% with saxagliptin and 0.80% with glipizide.
There was, however, a significantly smaller rise in HbA1c from week 24 to 52 with saxagliptin compared with glipizide (0.001% vs 0.004%) - indicating a sustained glycemic effect beyond week 24.
Treatment with saxagliptin was associated with a significantly smaller proportion of patients with hypoglycemic events than treatment with glipizide (3.0% vs 36.3%) and a divergent impact on body weight (mean change from baseline -1.1 kg with saxagliptin vs +1.1 kg with glipizide).
Excluding hypoglycemic events, the proportion of patients experiencing adverse events was similar (60.0% saxagliptin and 56.7% glipizide), although treatment-related adverse events were less common with saxagliptin than with glipizide (9.8% vs 31.2%), which was attributable to the higher frequency of hypoglycemia in glipizide patients.
Gause-Nilsson et al comment: "By using agents that differ in their mechanisms of action and side-effect profiles, combination regimens can better address the numerous pathophysiological abnormalities that characterize Type 2 diabetes while reducing safety and tolerability issues."
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By Andrew Czyzewski