Samuel S. Engel

Effect of Sitagliptin on Cardiovascular Outcomes in Type 2 Diabetes

BACKGROUND Data are lacking on the long-term effect on cardiovascular events of adding sitagliptin, a dipeptidyl peptidase 4 inhibitor, to usual care in patients with type 2 diabetes and cardiovascular disease. METHODS In this randomized, double-blind study, we assigned 14,671 patients to add either sitagliptin or placebo to their existing therapy. Open-label use of antihyperglycemic therapy was encouraged as required, aimed at reaching individually appropriate glycemic targets in all patients. To determine whether sitagliptin was noninferior to placebo, we used a relative risk of 1.3 as the marginal upper boundary. The primary cardiovascular outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. RESULTS During a median follow-up of 3.0 years, there was a small difference in glycated hemoglobin levels (least-squares mean difference for sitagliptin vs. placebo, -0.29 percentage points; 95% confidence interval [CI], -0.32 to -0.27). Overall, the primary outcome occurred in 839 patients in the sitagliptin group (11.4%; 4.06 per 100 person-years) and 851 patients in the placebo group (11.6%; 4.17 per 100 person-years). Sitagliptin was noninferior to placebo for the primary composite cardiovascular outcome (hazard ratio, 0.98; 95% CI, 0.88 to 1.09; P<0.001). Rates of hospitalization for heart failure did not differ between the two groups (hazard ratio, 1.00; 95% CI, 0.83 to 1.20; P=0.98). There were no significant between-group differences in rates of acute pancreatitis (P=0.07) or pancreatic cancer (P=0.32). CONCLUSIONS Among patients with type 2 diabetes and established cardiovascular disease, adding sitagliptin to usual care did not appear to increase the risk of major adverse cardiovascular events, hospitalization for heart failure, or other adverse events. (Funded by Merck Sharp & Dohme; TECOS ClinicalTrials.gov number, NCT00790205.).

Efficacy and safety of sitagliptin when added to insulin therapy in patients with type 2 diabetes

Objective: To evaluate the efficacy and tolerability of sitagliptin when added to insulin therapy alone or in combination with metformin in patients with type 2 diabetes.

Safety and tolerability of sitagliptin in clinical studies: a pooled analysis of data from 10,246 patients with type 2 diabetes.

BackgroundIn a previous pooled analysis of 12 double-blind clinical studies that included data on 6,139 patients with type 2 diabetes, treatment with sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, was shown to be generally well tolerated compared with treatment with control agents. As clinical development of sitagliptin continues, additional studies have been completed, and more patients have been exposed to sitagliptin. The purpose of the present analysis is to update the safety and tolerability assessment of sitagliptin by pooling data from 19 double-blind clinical studies.MethodsThe present analysis included data from 10,246 patients with type 2 diabetes who received either sitagliptin 100 mg/day (N = 5,429; sitagliptin group) or a comparator agent (placebo or an active comparator) (N = 4,817; non-exposed group). The 19 studies from which this pooled population was drawn represent the double-blind, randomized studies that included patients treated with the usual clinical dose of sitagliptin (100 mg/day) for between 12 weeks and 2 years and for which results were available as of July 2009. These 19 studies assessed sitagliptin taken as monotherapy, initial combination therapy with metformin or pioglitazone, or as add-on combination therapy with other antihyperglycemic agents (metformin, pioglitazone, a sulfonylurea ± metformin, insulin ± metformin, or rosiglitazone + metformin). Patients in the non-exposed group were taking placebo, metformin, pioglitazone, a sulfonylurea ± metformin, insulin ± metformin, or rosiglitazone + metformin. The analysis used patient-level data from each study to evaluate between-group differences in the exposure-adjusted incidence rates of adverse events.ResultsSummary measures of overall adverse events were similar in the sitagliptin and non-exposed groups, except for an increased incidence of drug-related adverse events in the non-exposed group. Incidence rates of specific adverse events were also generally similar between the two groups, except for increased incidence rates of hypoglycemia, related to the greater use of a sulfonylurea, and diarrhea, related to the greater use of metformin, in the non-exposed group and constipation in the sitagliptin group. Treatment with sitagliptin was not associated with an increased risk of major adverse cardiovascular events.ConclusionsIn this updated pooled safety analysis of data from 10,246 patients with type 2 diabetes, sitagliptin 100 mg/day was generally well tolerated in clinical trials of up to 2 years in duration.

Efficacy and safety of sitagliptin when added to ongoing metformin therapy in patients with type 2 diabetes

Aim:  To assess the addition of sitagliptin to ongoing metformin therapy in patients with type 2 diabetes who were inadequately controlled [haemoglobin A1c (HbA1c) 7–11%] on metformin monotherapy.

Sitagliptin: review of preclinical and clinical data regarding incidence of pancreatitis

Recent case reports of acute pancreatitis in patients with type 2 diabetes (T2DM) treated with incretin‐based therapies have triggered interest regarding the possibility of a mechanism‐based association between pancreatitis and glucagon‐like peptide‐1 mimetics or dipeptidyl peptidase‐4 (DPP‐4) inhibitors. The objective of this review was to describe the controlled preclinical and clinical trial data regarding the incidence of pancreatitis with sitagliptin, the first DPP‐4 inhibitor approved for use in patients with T2DM. Tissue samples from multiple animal species treated with sitagliptin for up to 2 years at plasma exposures substantially in excess of human exposure were evaluated to determine whether any potential gross or histomorphological changes suggestive of pancreatitis occurred. Sections were prepared by routine methods, stained with haematoxylin and eosin and examined microscopically. A pooled analysis of 19 controlled clinical trials, comprising 10,246 patients with T2DM treated for up to 2 years, was performed using patient‐level data from each study for the evaluation of clinical and laboratory adverse events. Adverse events were encoded using the Medical Dictionary for Regulatory Activities (MedDRA) version 12.0 system. Incidences of adverse events were adjusted for patient exposure. Tissue samples from preclinical studies in multiple animal species did not reveal any evidence of treatment‐related pancreatitis. The pooled analysis of controlled clinical trials revealed similar incidence rates of pancreatitis in patients treated with sitagliptin compared with those not treated with sitagliptin (0.08 events per 100 patient‐years vs. 0.10 events per 100 patient‐years, respectively). Preclinical and clinical trial data with sitagliptin to date do not indicate an increased risk of pancreatitis in patients with T2DM treated with sitagliptin.

Sulphonylureas and risk of cardiovascular disease: systematic review and meta-analysis

Sulphonylurea use has been linked with increased cardiovascular disease risk; however, previous studies have been inconsistent. Type 2 diabetes independently increases risk for cardiovascular disease, so understanding the link between longer‐term use of anti‐diabetic medications and cardiovascular disease has important clinical implications.

Cardiovascular safety of sitagliptin in patients with type 2 diabetes mellitus: a pooled analysis.

ObjectiveTo compare the incidence of cardiovascular events and mortality in patients with type 2 diabetes mellitus treated with sitagliptin or non-sitagliptin comparators.MethodsA post hoc assessment of cardiovascular safety in 14,611 patients was performed by pooling data from 25 double-blind studies, which randomised patients at baseline to sitagliptin 100 mg/day or a non-sitagliptin comparator (i.e., non-exposed). Included studies were limited to those at least 12 weeks in duration (range: 12 to 104 weeks). Patient-level data were used in this analysis of major adverse cardiovascular events (MACE) including ischaemic events and cardiovascular deaths. Analyses were performed in three cohorts: the entire 25-study cohort, the cohort from placebo-controlled portions of studies (n=19), and the cohort from studies comparing sitagliptin to a sulphonylurea (n=3).ResultsIn the entire cohort analysis, 78 patients had at least 1 reported MACE-related event, with 40 in the sitagliptin group and 38 in the non-exposed group. The exposure-adjusted incidence rate was 0.65 per 100 patient-years in the sitagliptin group and 0.74 in the non-exposed group (incidence rate ratio = 0.83 [95% confidence interval (CI): 0.53, 1.30]). In the analysis comparing sitagliptin to placebo, the exposure-adjusted incidence rate was 0.80 per 100-patient-years with sitagliptin and 0.76 with placebo (incidence rate ratio = 1.01 [95% CI: 0.55, 1.86]). In the analysis comparing sitagliptin to sulphonylurea, the exposure-adjusted incidence rate was 0.00 per 100 patient-years with sitagliptin and 0.86 with sulphonylurea (incidence rate ratio = 0.00 [95% CI: 0.00, 0.31]).ConclusionA pooled analysis of 25 randomised clinical trials does not indicate that treatment with sitagliptin increases cardiovascular risk in patients with type 2 diabetes mellitus. In a subanalysis, a higher rate of cardiovascular-related events was associated with sulphonylurea relative to sitagliptin.

The incidence of hypoglycaemia in Muslim patients with type 2 diabetes treated with sitagliptin or a sulphonylurea during Ramadan: a randomised trial

Aims:  To compare the incidence of symptomatic hypoglycaemia in fasting Muslim patients with type 2 diabetes treated with sitagliptin or a sulphonylurea during Ramadan.

Early combination therapy for the treatment of type 2 diabetes mellitus: systematic review and meta-analysis

Guidelines for type 2 diabetes recommend add‐on agents when metformin alone fails to provide adequate glycaemic control. However, early combination therapy may benefit health outcomes. We conducted a systematic review and meta‐analysis to investigate this question.

Association between hypoglycemia and inpatient mortality and length of hospital stay in hospitalized, insulin-treated patients

Abstract Objective: To assess the impact of hypoglycemia on clinical outcomes among hospitalized, insulin-treated patients. Methods: In a retrospective study, hospitalizations in 2005–2007 were identified from a US inpatient electronic medical records database. All encounters for insulin-treated patients with valid blood glucose measurement were included, except for those with a length of stay <24 hours or >30 days. In an encounter-based analysis, associations between hypoglycemic (glucose ≤70 mg/dL) or severe hypoglycemic (glucose ≤50 mg/dL) episodes and inpatient mortality, ischemic events, neurologic complications, and length of stay were evaluated. Results: Among 107,312 admissions, hypoglycemia occurred in 21,561 (20%) and severe hypoglycemia in 7539 (7%). Inpatient mortality occurred in 6.5% of hospitalizations with hypoglycemia and 3.8% of those without (p < 0.001). Inpatient mortality occurred in 7.6% of hospitalizations with a severe hypoglycemic event. Ischemic events (8.1 vs. 8.0%) and neurologic complications (3.8 vs. 3.7%) were similar in hospitalizations with and without a hypoglycemic event, respectively. In multivariate logistic regression analyses adjusting for age, gender, and selected comorbidities, hypoglycemia was associated with a significant increase in inpatient mortality risk (adjusted odds ratio (OR) = 1.66 [95% CI: 1.55, 1.78]). Similar results were observed with severe hypoglycemia (adjusted OR = 1.44 [1.38, 1.52]). Length of stay was increased in hospitalizations with hypoglycemia (median [interquartile range]: 8.2 days [4.9, 13.9] vs. 5.2 days [3.1, 8.3]; p < 0.0001). Limitations: Due to the nature of the data source, some data of interest were not available, including insulin dose and dose regimen, outpatient medical histories (including diabetes history), pre-hospitalization medications, and cause of death. Conclusions: Hypoglycemia was common among hospitalized patients receiving insulin and, while a direct causal relationship cannot be assumed, was associated with an increased risk of inpatient mortality and increased length of hospital stay. Hypoglycemia is an undesirable event and efforts to minimize in-hospital hypoglycemic events are warranted across the spectrum of hospitalized patients.