Long-term safety and tolerability of saxagliptin add-on therapy in older patients (aged ≥ 65 years) with type 2 diabetes

Abstract

Background: Treatment decisions for older patients with type 2 diabetes mellitus must balance glycemic control and adverse event risk. The objective of this study was to evaluate the long-term safety and tolerability of saxagliptin 5 mg as add-on therapy to common antihyperglycemic drugs in patients aged ≥ 65 years and <65 years.

Methods: Pooled adverse event data from three placebo-controlled trials of 76-206 weeks' duration in older (≥ 65 years) and younger (<65 years) patients receiving saxagliptin 5 mg or matching placebo added to metformin, glyburide, or a thiazolidinedione were analyzed. Measurements were calculated from day of first dose to specified event or last dose and included time at risk for adverse events, treatment-related adverse events, serious adverse events, adverse events leading to discontinuation, and events of special interest. Weighted incidence rates (number of events/total time) and incidence rate ratios (saxagliptin/placebo) with 95% confidence intervals were calculated (Mantel-Haenszel test).

Results: A total of 205 older (mean age 69 years; saxagliptin, n=99; placebo, n=106) and 1,055 younger (mean age 52 years; saxagliptin, n=531; placebo, n=524) patients were assessed. Regardless of age category, the adverse event incidence rates were generally similar between treatments, with confidence intervals for incidence rate ratios bridging 1. Treatment-related adverse events occurred in 36 older patients receiving saxagliptin versus 32 receiving placebo (incidence rate 34.1 versus 27.1 per 100 person-years) and in 150 younger patients in both treatment groups (incidence rate 24.0 versus 27.8 per 100 person-years). With saxagliptin versus placebo, serious adverse events occurred in eight versus 14 older (incidence rate 5.7 versus 9.9 per 100 person-years) and 49 versus 44 younger patients (incidence rate 6.5 versus 6.6 per 100 person-years). There were two deaths (one patient ≥ 65 years) with saxagliptin and six (none aged ≥ 65 years) with placebo. Older patients rarely experienced symptomatic confirmed hypoglycemia (fingerstick glucose ≤ 50 mg/dL; saxagliptin, n=1; placebo, n=2).

Conclusion: Saxagliptin add-on therapy was generally well tolerated in older patients aged ≥ 65 years with type 2 diabetes mellitus, with a long-term safety profile similar to that of placebo.

Keywords: glyburide; metformin; older patients; saxagliptin; thiazolidinedione.

Figure 1

IRRs of AEs by (A) category and (B) type with saxagliptin 5 mg versus placebo. Notes: Error bars are 95% CIs. ^aPoint estimate could not be computed, and CI for IRR was not provided. In the elderly patients in the saxagliptin 5 mg and placebo groups, treatment-related serious AEs were reported in 1 and 0 patients and death occurred in 1 and 0 patients, respectively. Abbreviations: AE, adverse event; CI, confidence interval; D/C, discontinuation; IRR, incidence rate ratio.