Tolerability of dipeptidyl peptidase-4 inhibitors: a review

Dipeptidyl peptidase-4 inhibitors and the risk of infection: A systematic review and meta-analysis of cardiovascular outcome trials

BACKGROUND

Since adverse events during treatment affect adherence and subsequent glycemic control, understanding the safety profile of oral anti-diabetic drugs is imperative for type 2 diabetes mellitus (T2DM) therapy.

AIM

To evaluate the risk of infection in patients with T2DM treated with dipeptidyl-peptidase 4 (DPP-4) inhibitors.

METHODS

Electronic databases were searched. The selection criteria included randomized controlled trials focused on cardiovascular outcomes. In these studies, the effects of DPP-4 inhibitors were directly compared to those of either other active anti-diabetic treatments or placebo. Six trials involving 53616 patients were deemed eligible. We calculated aggregate relative risks employing both random-effects and fixed-effects approaches, contingent upon the context.

RESULTS

The application of DPP-4 inhibitors showed no significant link to the overall infection risk [0.98 (0.95, 1.02)] or the risk of serious infections [0.96 (0.85, 1.08)], additionally, no significant associations were found with opportunistic infections [0.69 (0.46, 1.04)], site-specific infections [respiratory infection 0.99 (0.96, 1.03), urinary tract infections 1.02 (0.95, 1.10), abdominal and gastrointestinal infections 1.02 (0.83, 1.25), skin structure and soft tissue infections 0.81 (0.60, 1.09), bone infections 0.96 (0.68, 1.36), and bloodstream infections 0.97 (0.80, 1.18)].

CONCLUSION

This meta-analysis of data from cardiovascular outcome trials revealed no heightened infection risk in patients undergoing DPP-4 inhibitor therapy compared to control cohorts.

Incident infection risks depending on oral antidiabetic exposure in insulin-treated type 2 diabetes patients

Dipeptidyl peptidase-4 inhibitors (DPP4is) and sodium glucose cotransporter-2 inhibitors (SGLT2is) have been speculated to have a potential to increase infection risks in type 2 diabetes mellitus (T2DM) patients. We performed a cohort study using the Korean health insurance data to investigate infection risks with each drug class relative to metformin in insulin-treated T2DM patients. After propensity score matching, we included 1,498 and 749 patients in DPP4i + insulin vs metformin + insulin and 300 and 549 patients in SGLT2i + insulin vs metformin + insulin, respectively. In stratified analyses per patient factor, none of the odds ratios (ORs) were associated with a statistical significance across respiratory, genital, and urinary tract infections (UTIs), except that of the male stratum for respiratory infections (OR 0.77, p = 0.04). With regard to SGLT2is, a higher risk of genital infections was analyzed with their use than with metformin therapy (OR 1.76, p = 0.03). In stratified analyses, the OR for genital infections remained significant in the baseline cardiovascular disease stratum (OR 2.29, p = 0.01). No increased UTI risk was detected with SGLT2is compared against metformin. In this study on insulin-receiving T2DM patients, DPP4is were not associated with increased infection risks, whereas SGLT2is led to a higher risk for genital infections, but not for UTIs, relative to metformin.

Effects of Sitagliptin on Metabolic Indices and Hormone Levels in Polycystic Ovary Syndrome: a Meta-analysis of Randomized Controlled Trials

To evaluate the effects of sitagliptin on the metabolic indices and hormone levels in patients with polycystic ovary syndrome (PCOS). PubMed, EMBASE, Web of Science, Cochrane Library, WanFang Data, and China National Knowledge Infrastructure (CNKI) were searched for randomized controlled trials (RCTs) published up to March 2022. Eligible studies were identified based on the inclusion criteria. The primary outcomes included the homeostasis model assessment of insulin resistance (HOMA-IR), body mass index (BMI), and total testosterone level (TT). Other outcomes included levels of sex hormones, glucose, and lipid metabolism. Forty-five studies were initially identified, and 6 RCTs with 394 patients were finally included in this study. The meta-analysis results suggest that sitagliptin improved HOMA-IR (WMD =  - 0.35; 95% CI (- 0.62, - 0.08); P = 0.01), BMI (WMD =  - 1.27; 95% CI (- 1.76, - 0.77); P < 0.00001), TT (SMD =  - 0.66; 95% CI (- 1.25, - 0.07); P = 0.03), and HDL-C (SMD = 0.11; 95% CI (0.03, 0.18); P = 0.005). No significant differences were observed between the sitagliptin and control groups in other outcomes and in terms of adverse events. Evidence from meta-analyses suggests that sitagliptin was superior in improving insulin sensitivity, total serum testosterone, high-density lipoprotein, and body mass index. However, due to the limitations of published studies, it is difficult to draw a definite conclusion. Larger, higher-quality studies are needed to evaluate the efficacy of sitagliptin in women with PCOS.

Adherence to Oral Antidiabetic Drugs in Patients with Type 2 Diabetes: Systematic Review and Meta-Analysis

Poor adherence to oral antidiabetic drugs (OADs) in patients with type 2 diabetes (T2D) can lead to therapy failure and risk of complications. The aim of this study was to produce an adherence proportion to OADs and estimate the association between good adherence and good glycemic control in patients with T2D. We searched in MEDLINE, Scopus, and CENTRAL databases to find observational studies on therapeutic adherence in OAD users. We calculated the proportion of adherent patients to the total number of participants for each study and pooled study-specific adherence proportions using random effect models with Freeman-Tukey transformation. We also calculated the odds ratio (OR) of having good glycemic control and good adherence and pooled study-specific OR with the generic inverse variance method. A total of 156 studies (10,041,928 patients) were included in the systematic review and meta-analysis. The pooled proportion of adherent patients was 54% (95% confidence interval, CI: 51-58%). We observed a significant association between good glycemic control and good adherence (OR: 1.33; 95% CI: 1.17-1.51). This study demonstrated that adherence to OADs in patients with T2D is sub-optimal. Improving therapeutic adherence through health-promoting programs and prescription of personalized therapies could be an effective strategy to reduce the risk of complications.

Structural Characterization and Hypoglycemic Function of Polysaccharides from Cordyceps cicadae

The polysaccharides isolated and purified from different parts of the medicinal fungus Cordyceps cicadae were identified, and three extracts displaying significant biological activities were selected for further study. The bacterium substance polysaccharides (BSP), spore powder polysaccharides (SPP), and pure powder polysaccharides (PPP) were separated, purified, and collected from the sclerotia, spores, and fruiting bodies of Cordyceps cicadae, respectively. The structures of Cordyceps cicadae polysaccharides were analyzed using gas chromatography, Fourier-transform infrared spectroscopy, methylation analysis, and one-dimensional (¹H and ¹³C) nuclear magnetic resonance spectroscopy. Moreover, the hypoglycemic effect of Cordyceps cicadae polysaccharides was examined in both in vitro and in vivo models. BSP, SPP, and PPP significantly increased glucose absorption in HepG2 cells, and alleviated insulin resistance (IR) in the in vitro model. SPP was the most effective, and was therefore selected for further study of its hypoglycemic effect in vivo. SPP effectively improved body weight and glucose and lipid metabolism in type 2 diabetes model mice, in addition to exerting a protective effect on liver injury. SPP regulated the mRNA expression of key PI3K/Akt genes involved in the insulin signaling pathway. The hypoglycemic mechanism of SPP may reduce hepatic insulin resistance by activating the PI3K/Akt signaling pathway. Spore powder polysaccharides (SPP) extracted from Cordyceps cicadae effectively improved body weight and glucose and lipid metabolism in type 2 diabetes model mice, in addition to exerting a protective effect on liver injury. The mechanism underlying the hypoglycemic effect of SPP regulates the mRNA expression of key PI3K/Akt genes involved in the insulin signaling pathway to alleviate insulin resistance. Our results provide a theoretical basis for research into the hypoglycemic effect of Cordyceps cicadae, and lay the foundation for the development of functional products.

Therapeutic Effects of Switching to Anagliptin from Other DPP-4 Inhibitors in T2DM Patients with Inadequate Glycemic Control: A Non-interventional, Single-Arm, Open-Label, Multicenter Observational Study

INTRODUCTION

The effects of switching DPP-4 inhibitors in type 2 diabetes mellitus (T2DM) patients are being widely studied. However, information of which factors affect the therapeutic response is limited. We evaluated the difference in HbA1c lowering effect by comorbidity and other variables after switching to anagliptin in patients with T2DM inadequately controlled by other DPP-4 inhibitors.

METHODS

In a multicenter, open-label, single-arm, prospective observational study, patients with T2DM, HbA1c ≥ 7.0% who have taken DPP-4 inhibitors other than anagliptin, either alone or in combination (DPP-4 inhibitors + metformin/sulfonylurea (SU)/thiazolidinedione (TZD)/insulin), for at least 8 weeks were enrolled. After the switch to anagliptin, HbA1c and available clinical characteristics were determined.

RESULTS

The change in HbA1c levels from baseline to week 12 and 24 was - 0.40% and - 0.42% in all patients. However, comparing the subgroups without and with comorbidities, the change in HbA1c levels at weeks 12 and 24 was - 0.68% and - 0.89% vs. - 0.27% and 0.22%, respectively. In addition, the proportion of patients achieving HbA1c < 7% from baseline to week 12 and 24 was increased to 70% and 70% vs. 20% and 24%, respectively. Duration of T2DM and different subtype classes of DPP-4 inhibitor did not significantly contribute to the change in HbA1c.

CONCLUSION

In patients with T2DM poorly controlled by other DPP-4 inhibitors, HbA1c levels were significantly decreased after switching to anagliptin. Given that the change in HbA1c was greater in patients without comorbidities than in patients with comorbidities, switching to anagliptin before adding other oral hypoglycemic agents (OHAs) may be an option in patients without comorbidities.

Reporting and methodological quality of systematic reviews of DPP-4 inhibitors for patients with type 2 diabetes mellitus: an evidence-based mapping

AIMS

To evaluate the reporting and methodological quality of relevant systematic reviews (SRs) and meta-analyses (MAs) on Dipeptidyl peptidase-4 inhibitors (DPP-4I) for Type 2 diabetes mellitus (T2DM).

METHODS

Relevant SRs and MAs on T2DM and DPP-4I published between 2017 and November 2021 were retrieved from PubMed, Embase, Cochrane Library, Web of Science, VIP, CNKI, CBM, and WanFang databases. Two independent reviewers performed the search, selection, and data extraction. The reporting and methodological quality of the reviewers was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR 2) tools. The relationship between reporting and methodological quality score was assessed with the Spearman correlation test.

RESULTS

Twenty-one studies involving 151,715 participants were included in the study. This overview showed that DPP-4I was safer and more efficacious than other anti-hyperglycemic drugs (OADs) in treating T2DM. The methodological quality of one SR was low, while the rest were very low. Thus, refinements are needed in the quality of protocol and registration information, a complete search strategy, the summary of the evidence, the listing of excluded studies, assessing the potential impact of risk of bias in RCTs, and discussing the RoB on MA results, and the funding of RCTs need improvement for generating SR. In addition, the reporting and methodological quality scores were moderately correlated (r_S = 0.66, P = 0.001).

CONCLUSIONS

DPP-4I is safer and more efficacious than OADs in treating T2DM. However, the reporting and methodological quality of the related SRs was unsatisfactory. Therefore, PRISMA and AMSTAR 2 analyses should be followed to enhance the overall quality of future SRs.

The impact of a novel Chinese yam-derived polysaccharide on blood glucose control in HFD and STZ-induced diabetic C57BL/6 mice

Chinese yam, as a kind of traditional “medicine and food homologous food” in Asia, could assistance to digestion, nourish the lungs and relieve cough. Some research also suggested that Chinese...

A Multicentre, Multinational, Open-Label, 52-Week Extension Study of Gemigliptin (LC15-0444) Monotherapy in Patients with Type 2 Diabetes Mellitus

The purpose of this extension study was to assess the long-term efficacy and safety of gemigliptin 50 mg in patients with type 2 diabetes mellitus (T2DM). Patients with T2DM who had completed the initial 24-week study comparing gemigliptin monotherapy with placebo were eligible to enrol. In the open-label, 28-week extension study, all enrolled patients received gemigliptin, regardless of the treatment received during the initial 24-week study period. The mean reduction±standard deviation (SD) in glycosylated hemoglobin (HbA1c) observed after 24 weeks of treatment (-0.6%±1.1%) was further decreased for the gemi-gemi group and the mean change in HbA1c at week 52 from baseline was -0.9%±1.2% (P<0.0001). For the pbo-gemi group, HbA1c decreased after they were switched to gemigliptin, and the mean change in HbA1c at week 52 from baseline was -0.7%±1.2% (P<0.0001). Furthermore, the overall incidence of adverse events demonstrated that gemigliptin was safe and well tolerated up to 52 weeks.

Adverse event profiles of dipeptidyl peptidase-4 inhibitors: data mining of the public version of the FDA adverse event reporting system

BACKGROUND

To describe and analyze the patterns of adverse events associated with dipeptidyl peptidase-4 inhibitors (DPP-4is) (sitagliptin, saxagliptin, linagliptin, vildagliptin, and alogliptin) from the FDA Adverse Event Reporting System (FAERS) and to highlight areas of safety concerns.

METHODS

Adverse events spontaneously submitted to the FAERS between 2004 Q1 to 2019 Q2 were included. The online tool OpenVigil 2.1 was used to query the database. The research relied on definitions of preferred terms (PTs) specified by the Medical Dictionary for Regulatory Activities (MedDRA) and the standardized MedDRA Queries (SMQ). The reporting odds ratio (ROR), with 95% confidence intervals (CIs) was calculated for disproportionality analysis.

RESULTS

Over 16 years, a total of 9706 adverse event reports were identified. Alogliptin was excluded from further analysis due to insufficient sample size. Compared with the non-insulin antidiabetic drugs, the four DPP-4is were all disproportionately associated with four SMQs: "gastrointestinal nonspecific inflammation and dysfunctional conditions," "hypersensitivity," "severe cutaneous adverse reactions," and "noninfectious diarrhoea". As for PT level analyses, DPP-4is are associated with higher reporting of the gastrointestinal tract, pancreas, malignancies, infection, musculoskeletal disorders, general disorders, hypersensitivity, and skin AEs.

CONCLUSIONS

Data mining of the FAERS is useful for examining DPP-4 inhibitors-associated adverse events. The findings of the present study are compatible with clinical experience, and it provides valuable information to decision-makers and healthcare providers in clinical practice.

The efficacy and safety of dipeptidyl peptidase-4 inhibitors compared to other oral glucose-lowering medications in the treatment of type 2 diabetes

INTRODUCTION

The dipeptidyl peptidase-4 inhibitors (DPP-4is), which belong to the class of incretin-based medications, are recommended as second or third-line therapies in guidelines for the management of type 2 diabetes mellitus. They have a favorable drug tolerability and safety profile compared to other glucose-lowering agents.

OBJECTIVE

This review discusses data concerning the use of DPP-4is and their cardiovascular profile, and gives an updated comparison with the other oral glucose-lowering medications with regards to safety and efficacy. Currently available original studies, abstracts, reviews articles, systematic reviews and meta-analyses were included in the review.

DISCUSSION

DPP4is are moderately efficient in decreasing the HbA1c by an average of 0.5% as monotherapy, and 1.0% in combination therapy with other drugs. They have a good tolerability and safety profile compared to other glucose-lowering drugs. However, there are possible risks pertaining to acute pancreatitis and pancreatic cancer.

CONCLUSION

Cardiovascular outcome trials thus far have proven the cardiovascular safety for ischemic events in patients treated with sitagliptin, saxagliptin, alogliptin, linagliptin and vildagliptin. Data showing increased rate of hospitalisation in the case of saxagliptin did not seem to be a class effect.

Diabetes pharmacotherapy and effects on the musculoskeletal system

Persons with type 1 or type 2 diabetes have a significantly higher fracture risk than age-matched persons without diabetes, attributed to disease-specific deficits in the microarchitecture and material properties of bone tissue. Therefore, independent effects of diabetes drugs on skeletal integrity are vitally important. Studies of incretin-based therapies have shown divergent effects of different agents on fracture risk, including detrimental, beneficial, and neutral effects. The sulfonylurea class of drugs, owing to its hypoglycemic potential, is thought to amplify the risk of fall-related fractures, particularly in the elderly. Other agents such as the biguanides may, in fact, be osteo-anabolic. In contrast, despite similarly expected anabolic properties of insulin, data suggests that insulin pharmacotherapy itself, particularly in type 2 diabetes, may be a risk factor for fracture, negatively associated with determinants of bone quality and bone strength. Finally, sodium-dependent glucose co-transporter 2 inhibitors have been associated with an increased risk of atypical fractures in select populations, and possibly with an increase in lower extremity amputation with specific SGLT2I drugs. The role of skeletal muscle, as a potential mediator and determinant of bone quality, is also a relevant area of exploration. Currently, data regarding the impact of glucose lowering medications on diabetes-related muscle atrophy is more limited, although preclinical studies suggest that various hypoglycemic agents may have either aggravating (sulfonylureas, glinides) or repairing (thiazolidinediones, biguanides, incretins) effects on skeletal muscle atrophy, thereby influencing bone quality. Hence, the therapeutic efficacy of each hypoglycemic agent must also be evaluated in light of its impact, alone or in combination, on musculoskeletal health, when determining an individualized treatment approach. Moreover, the effect of newer medications (potentially seeking expanded clinical indication into the pediatric age range) on the growing skeleton is largely unknown. Herein, we review the available literature regarding effects of diabetes pharmacotherapy, by drug class and/or by clinical indication, on the musculoskeletal health of persons with diabetes.

DPP4 inhibitors and cardiovascular outcomes: safety on heart failure

Diabetes is an important risk factor for cardiovascular disease. However, clinical data suggests intensive glycemic control significantly increase rather than decrease cardiovascular mortality, which is largely due to the fact that a majority of oral anti-diabetic drugs have adverse cardiovascular effect. There are several large-scale clinical trials evaluating the cardiovascular safety of DPP4 inhibitors, a novel class of oral anti-diabetic medications, which have been recently completed. They were proven to be safe with regard to cardiovascular outcomes. However, concerns on the safety of heart failure have been raised as the SAVOR-TIMI 53 trial reported a 27% increase in the risk for heart failure hospitalization in diabetic patients treated with DPP4 inhibitor saxagliptin. In this review, we will discuss recent advances in the heart failure effects of DPP4 inhibition and GLP-1 agonism.

The safety of gliptins : updated data in 2018

INTRODUCTION

Dipeptidyl peptidase-4 inhibitors (DPP-4is) are generally considered as glucose-lowering agents with a safe profile in type 2 diabetes.

AREAS COVERED

An updated review of recent safety data from randomised controlled trials, observational studies, meta-analyses, pharmacovigilance reports regarding alogliptin, linagliptin, saxagliptin, sitagliptin, and vildagliptin, with a special focus on risks of hypoglycemia, pancreatitis and pancreatic cancer, major cardiovascular events, hospitalisation for heart failure and other new safety issues, such as bone fractures and arthralgia. The safety of DPP-4i use in special populations, elderly patients, patients with renal impairment, liver disease or heart failure, will also be discussed.

EXPERT OPINION

The good tolerance/safety profile of DPP-4is has been largely confirmed, including in more fragile populations, with no gastrointestinal adverse effects and a minimal risk of hypoglycemia. DPP-4is appear to be associated with a small increased incidence of acute pancreatitis in placebo-controlled trials, although most observational studies are reassuring. Most recent studies with DPP-4is do not confirm the increased risk of hospitalisation for heart failure reported with saxagliptin in SAVOR-TIMI 53, but further post-marketing surveillance is still recommended. New adverse events have been reported such as arthralgia, yet a causal relationship remains unclear.

Gastrointestinal Adverse Events of Dipeptidyl Peptidase 4 Inhibitors in Type 2 Diabetes: A Systematic Review and Network Meta-analysis

PURPOSE

The purpose of this study was to systematically evaluate the effect of dipeptidyl peptidase 4 inhibitors on gastrointestinal adverse events in patients with type 2 diabetes.

METHODS

MEDLINE, Embase, the Cochrane Library, and ClinicalTrials.gov were searched from inception through April 28, 2016. Randomized controlled trials that compared dipeptidyl peptidase 4 inhibitor-based therapies with placebo and other hypoglycemic agents in type 2 diabetes were included. The duration of studies was at least 4 weeks.

FINDINGS

A total of 165 randomized controlled trials and 122,072 patients were included in the study. Dipeptidyl peptidase 4 inhibitors did not increase the incidence of gastrointestinal adverse events after the treatment with alogliptin (odds ratio [OR] = 0.83; 95% CI, 0.59-1.15), linagliptin (OR = 1.11; 95% CI, 0.92-1.35), saxagliptin (OR = 0.96; 95% CI, 0.80-1.15), sitagliptin (OR = 0.95; 95% CI, 0.64-1.14), teneligliptin (OR = 1.50; 95% CI, 0.81-2.77), and vildagliptin (OR = 0.80; 95% CI, 0.63-1.01) compared with placebo. Compared with glucagon-like peptide 1 receptor agonists, dipeptidyl peptidase 4 inhibitors significantly decreased the incidence of gastrointestinal adverse events with alogliptin (OR = 0.26; 95% CI, 0.15-0.44), linagliptin (OR = 0.43; 95% CI, 0.25-0.74), saxagliptin (OR = 0.28; 95% CI, 0.17-0.46), sitagliptin (OR = 0.24; 95% CI, 0.17-0.35), and vildagliptin (OR = 0.27; 95% CI, 0.18-0.41). Dipeptidyl peptidase 4 inhibitors were not associated with an increased risk of gastrointestinal adverse events relative to metformin and α-glucosidase inhibitors, respectively.

IMPLICATIONS

The network meta-analysis found that compared with glucagon-like peptide 1 receptor agonists, metformin, and α-glucosidase inhibitor, dipeptidyl peptidase 4 inhibitors are associated with a lower incidence of gastrointestinal adverse events.

Alogliptin for the treatment of type 2 diabetes: a drug safety evaluation

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors such as alogliptin are becoming more widely established as treatment options for patients with type 2 diabetes (T2DM) because of their ability to improve glycemic control without increasing the risk of hypoglycemia or weight gain. New therapies with improved safety profiles are needed, especially because of the chronic and progressive nature of T2DM.

AREAS COVERED

In this article, the overall safety and tolerability of alogliptin are evaluated based upon a review of the literature. In particular, adverse events (AEs) that have been of interest for the DPP-4 class of drugs, such as the risk of major cardiovascular (CV) events and acute pancreatitis, will be investigated in detail.

EXPERT OPINION

Alogliptin is generally well-tolerated in a broad range of patient populations including different ethnic groups and the elderly. In the pivotal EXAMINE clinical trial, alogliptin was found not to be associated with an increased risk of major CV events or acute pancreatitis/pancreatic cancer.

Effects of vildagliptin versus saxagliptin on daily acute glucose fluctuations in Chinese patients with T2DM inadequately controlled with a combination of metformin and sulfonylurea

Objective The present study aimed to compare the effects of the dipeptidyl peptidase-4 (DPP-4) inhibitors vildagliptin and saxagliptin on 24 hour acute glucose fluctuations in Chinese patients with type 2 diabetes mellitus (T2DM) inadequately controlled with a combination of metformin and sulfonylurea. Research design and methods This was a 24 week, prospective, randomized, open-label, active-controlled study. Patients (N = 73) with T2DM who had inadequate glycemic control (HbA1c 7.0%-10.0%) with a stable dosage of metformin plus gliclazide for more than 3 months were randomized to receive either vildagliptin 50 mg twice daily (BID, n = 37) or saxagliptin 5 mg once daily (QD, n = 36). Change in mean amplitude of glycemic excursions (MAGE) was assessed at the end of 24 weeks. Results At baseline, the mean (±SD) age was 62.9 ± 6.55 years, disease duration was 7.0 ± 2.33 years, and HbA1c was 8.4 ± 0.68%. After 24 weeks of treatment, the MAGE decreased from 5.81 ± 1.16 mmol/L to 4.06 ± 0.86 mmol/L (p<0.001) in the vildagliptin group and from 5.66 ± 1.14 mmol/L to 4.79 ± 1.25 mmol/L (p = 0.003) in the saxagliptin group. The mean change in MAGE in the vildagliptin group was significantly greater than that in the saxagliptin group (1.74 ± 0.48 mmol/L vs. 0.87 ± 0.40 mmol/L, p<0.001). The mean change in HbA1c, from baseline to the study endpoint, in the vildagliptin and saxagliptin groups, was 1.22 ± 0.40% and 1.07 ± 0.36%, respectively, with no significant difference between the groups (p = 0.091). The overall safety and tolerability of vildagliptin and saxagliptin were similar. The limitations of the study were a small number of patients and open-label administration of the study drug. Conclusion Vildagliptin produced a significantly greater reduction in acute glucose fluctuations compared with saxagliptin when added to a dual combination of metformin and sulfonylurea in Chinese patients with T2DM. Chinese clinical trial registration number ChiCTR-TRC-13003858.

Recent progress in natural products as DPP-4 inhibitors

Diabetes mellitus is a chronic disease affecting patients' daily life and increasing patients' risk of other complication. Dipeptidyl peptidase-4 (DPP-4) is a serine aminopeptidase, which is one of the validated targets for Type 2 diabetes therapy due to its regulatory effect of incretin hormone. Seven DPP-4 inhibitors are commercially available nowadays on the market as Type 2 diabetes drugs. They are all chemically synthesized compounds with good therapeutic effects, but long-term safety remains unknown. On the other hand, nature provides a rich source for search of desired safe and effective medications; and actually more than half of the drugs on market are natural product related. Therefore, a systematic search for new DPP-4 inhibitors from nature sources seems to be of great utility for developing novel antidiabetic drugs. This review summarized recent progress of DPP-4 inhibitors from natural products, revealed that both pure natural products and the crude extracts of herbs or the hydrolyzates of proteins are active as DPP-4 inhibitors. Therefore, both could be served as useful clues for developing next generation of antidiabetes medicines via inhibiting DPP-4 activity.

Association between therapy with dipeptidyl peptidase-4 (DPP-4) inhibitors and risk of ileus: a cohort study

Background

Three cases of ileus have been published among dipeptidyl peptidase-4 (DPP-4) inhibitor users in Japan. The purpose of this study was to estimate and compare incidence rates of ileus among alogliptin users and users of other DPP-4 inhibitors, glucagon-like peptide 1 (GLP-1) receptor agonists, and voglibose.

Methods

We used the Medical Data Vision database in Japan to conduct a retrospective cohort study among type 2 diabetes mellitus (T2DM) patients who were new users of alogliptin, other DPP-4 inhibitors, GLP-1 receptor agonists, or voglibose between 1 April 2010 and 30 April 2014. The primary outcome was an incident diagnosis of ileus. Kaplan-Meier survival curves were used to estimate ileus events over time. Adjusted Poisson regression models were used to estimate incidence rate ratios (IRR) for ileus and 95 % confidence intervals (CI) by comparing alogliptin users to users of the other study drugs.

Results

We identified 82,386 patients with T2DM. In the adjusted model, there was no difference in risk of ileus among patients exposed to alogliptin compared with patients exposed to other DPP-4 inhibitors (IRR 1.15, 95 % CI 0.75-1.75) or GLP-1 receptor agonists (IRR 0.42, 95 % CI 0.14-1.20). The risk of ileus was significantly lower among patients exposed to alogliptin compared with patients exposed to voglibose (IRR 0.55, 95 % CI 0.35-0.88).

Conclusions

The independent risk of ileus among new users of alogliptin did not significantly differ compared with new users of other DPP-4 inhibitors or GLP-1 receptor agonists but was significantly lower than new users of voglibose.

Sodium glucose co-transporter 2 (SGLT2) inhibitors: new among antidiabetic drugs

Type 2 diabetes is characterized by decreased insulin secretion and sensitivity. The available oral anti-diabetic drugs act on many different molecular sites. The most used of oral anti-diabetic agents is metformin that activates glucose transport vesicles to the cell surface. Others are: the sulphonylureas; agents acting on the incretin system; GLP-1 agonists; dipetidylpeptidase-4 inhibitors; meglinitide analogues; and the thiazolidinediones. Despite these many drugs acting by different mechanisms, glycaemic control often remains elusive. None of these drugs have a primary renal mechanism of action on the kidneys, where almost all glucose excreted is normally reabsorbed. That is where the inhibitors of glucose reuptake (sodium-glucose cotransporter 2, SGLT2) have a unique site of action. Promotion of urinary loss of glucose by SGLT2 inhibitors embodies a new principle of control in type 2 diabetes that has several advantages with some urogenital side-effects, both of which are evaluated in this review. Specific approvals include use as monotherapy, when diet and exercise alone do not provide adequate glycaemic control in patients for whom the use of metformin is considered inappropriate due to intolerance or contraindications, or as add-on therapy with other anti-hyperglycaemic medicinal products including insulin, when these together with diet and exercise, do not provide adequate glycemic control. The basic mechanisms are improved β-cell function and insulin sensitivity. When compared with sulphonylureas or other oral antidiabetic agents, SGLT2 inhibitors provide greater HbA1c reduction. Urogenital side-effects related to the enhanced glycosuria can be troublesome, yet seldom lead to discontinuation. On this background, studies are analysed that compare SGLT2 inhibitors with other oral antidiabetic agents. Their unique mode of action, unloading the excess glycaemic load, contrasts with other oral agents that all act to counter the effects of diabetic hyperglycaemia.

DPP-4 inhibitors: pharmacological differences and their clinical implications

INTRODUCTION

Recently, incretin-based therapy was introduced for the treatment of type 2 diabetes (T2D). In particular, dipeptidyl peptidase-4 inhibitors (DPP-4i) (sitagliptin, vildagliptin, saxagliptin, linagliptin and alogliptin) play an increasing role in the management of T2D.

AREAS COVERED

An extensive literature search was performed to analyze the pharmacological characteristics of DPP-4i and their clinical implications.

EXPERT OPINION

DPP-4i present significant pharmacokinetic differences. They also differ in chemical structure, in the interaction with distinct subsites of the enzyme and in different levels of selectivity and potency of enzyme inhibition. Moreover, disparities in the effects on glycated hemoglobin, glucagon-like peptide-1 and glucagon levels and on glucose variability have been observed. However, indirect comparisons indicate that all DPP-4i have a similar safety and efficacy profiles. DPP-4i are preferred in overweight/obese and elderly patients because of the advantages of minimal or no influence on weight gain and low risk of hypoglycemia. For the same reasons, DPP-4i can be safely combined with insulin. However, currently cardiovascular outcomes related to DPP-4i are widely debated and the available evidence is controversial. Today, long-term studies are still in progress and upcoming results will allow us to better define the strengths and limits of this therapeutic class.

Safety of dipeptidyl peptidase-4 inhibitors for treating type 2 diabetes

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) occupy a growing place in the armamentarium of drugs used for the management of hyperglycemia in type 2 diabetes, although some safety concerns have been raised in recent years.

AREAS COVERED

An updated review providing an analysis of available safety data (meta-analyses, randomized controlled trials, observational cohort and case-control studies and pharmacovigilance reports) with five commercialized DPP-4 inhibitors (sitagliptin, vildagliptin, saxagliptin, alogliptin, linagliptin). A special focus is given to overall safety profile; pancreatic adverse events (AEs) (acute pancreatitis, pancreatic cancer); overall cardiovascular safety (myocardial infarction and stroke); congestive heart failure concern and finally, safety in special populations (elderly, renal impairment).

EXPERT OPINION

The good tolerance/safety profile of DPP-4 inhibitors has been largely confirmed, including in more fragile populations (elderly, renal impairment) with almost no increased risk of infection or gastrointestinal AEs, no weight gain and a minimal risk of hypoglycemia. Although an increased risk of acute pancreatitis and pancreatic cancer was suspected, the complete set of available data appears reassuring so far. Cardiovascular safety of DPP-4 inhibitors has been proven but an unexpected increased risk of heart failure has been reported which should be confirmed in ongoing trials and better understood. Further postmarketing surveillance is recommended.

Should sulfonylureas remain an acceptable first-line add-on to metformin therapy in patients with type 2 diabetes? No, it's time to move on!

Since their introduction to clinical practice in the 1950s, sulfonylureas have been widely prescribed for use in patients with type 2 diabetes. Of all the other medications currently available for clinical use, only metformin has been used more frequently. However, several new drug classes have emerged that are reported to have equal glucose-lowering efficacy and greater safety when added to treatment of patients in whom metformin monotherapy is no longer sufficient. Moreover, current arguments also suggest that the alternative drugs may be superior to sulfonylureas with regard to the risk of cardiovascular complications. Thus, while there is universal agreement that metformin should remain the first-line pharmacologic therapy for those in whom lifestyle modification is insufficient to control hyperglycemia, there is no consensus as to which drug should be added to metformin. Therefore, given the current controversy, we provide a Point-Counterpoint on this issue. In the preceding point narrative, Dr. Abrahamson provides his argument suggesting that avoiding use of sulfonylureas as a class of medication as an add-on to metformin is not appropriate as there are many patients whose glycemic control would improve with use of these drugs with minimal risk of adverse events. In the counterpoint narrative below, Dr. Genuth suggests there is no longer a need for sulfonylureas to remain a first-line addition to metformin for those patients whose clinical characteristics are appropriate and whose health insurance and/or financial resources make an alternative drug affordable.

Protocol for a large-scale prospective observational study with alogliptin in patients with type 2 diabetes: J-BRAND Registry

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors including alogliptin are categorised as a newer class of oral hypoglycaemic, antidiabetic drugs to suppress the degradation of incretin hormones ((glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP)) by DPP-4. We have scheduled a large-scale, multicentre, prospective, observational study (Japan-Based clinical ReseArch Network for Diabetes Registry: J-BRAND Registry) to construct an extensive database over a long-term clinical course in patients with type 2 diabetes receiving oral hypoglycaemic agents (OHAs) and to evaluate the safety and efficacy of alogliptin in Japanese population.

METHODS AND ANALYSIS

20,000 patients with type 2 diabetes will be registered into two groups of 10,000 each: group A patients will be treated with alogliptin, while group B patients will be treated with non-DPP-4 inhibitor OHA(s). Approximately 300 institutions nationwide will enrol and assign eligible patients equally to either group. Each patient's data will be collected every 6 months for a 3-year period, during which time treatment with OHA(s) may be changed or discontinued, as per package insert for each OHA. Primary end points are safety variables to be compared between the two groups and their subgroups, with respect to hypoglycaemia, pancreatitis, skin disorders, infections and cancer. Secondary end points are efficacy variables including from-baseline changes of A1c, fasting glucose, fasting insulin and urinary albumin, which will be compared between groups/subgroups. New onset and progression of microangiopathy will also be evaluated against OHA(s). Overall, the J-BRAND Registry will evaluate the safety and efficacy of antidiabetic OHA(s) including alogliptin, based on a large-scale database.

ETHICS AND DISSEMINATION

This study will be conducted with the highest respect for individual participants according to this protocol, the Declaration of Helsinki, the Ethical Guidelines for Clinical Research (Japan Ministry of Health, Labour and Welfare, 2008) and relevant laws/regulations. The present study will construct a valuable database of patients with type 2 diabetes treated with OHA(s) including alogliptin.

TRIAL REGISTRATION NUMBER

UMIN000007976.

DPP IV inhibitor treatment attenuates bone loss and improves mechanical bone strength in male diabetic rats

Dipeptidyl peptidase IV (DPP IV) modulates protein activity by removing dipeptides. DPP IV inhibitors are currently used to improve glucose tolerance in type 2 diabetes patients. DPP IV substrates not only increase insulin secretion but also affect bone metabolism. In this study, the effect of DPP IV inhibitor sitagliptin on bone was evaluated in normal and streptozotocin-induced diabetic rats. This study included 64 male Wistar rats divided into four groups (n = 16): two diabetic and two control groups. One diabetic and one control group received sitagliptin through drinking water. Tibiae were scanned every 3 wk using an in vivo μCT scanner. After 6 and 12 wk, rats were euthanized for histomorphometric analysis of bone parameters. The mechanical resistance of femora to fracture was assessed using a three-point bending test, and serum levels of bone metabolic markers were measured. Efficient DPP IV inhibition was achieved in sitagliptin-treated groups. Trabecular bone loss, the decrease in trabecular number, and the increase in trabecular spacing was attenuated through sitagliptin treatment in diabetic rats, as shown by in vivo μCT. Bone histomorphometry was in line with these results. μCT analysis furthermore showed that sitagliptin prevented cortical bone growth stagnation in diabetic rats, resulting in stronger femora during three-point bending. Finally, the serum levels of the resorption marker CTX-I were significantly lower in sitagliptin-treated diabetic animals compared with untreated diabetic animals. In conclusion, sitagliptin treatment attenuates bone loss and increases bone strength in diabetic rats probably through the reduction of bone resorption and independent of glycemic management.

Randomized controlled clinical trial of a combination therapy of vildagliptin plus an α-glucosidase inhibitor for patients with type II diabetes mellitus

The aim of this study was to assess the efficacy of a combination therapy of vildagliptin plus an α-glucosidase inhibitor for patients with type II diabetes mellitus. Type II diabetic patients exhibiting poor glycemic control following α-glucosidase inhibitor treatment for at least two months were selected and randomly distributed into vildagliptin and placebo groups. The body weight, fasting blood glucose (FBG), postprandial glucose (PPG), glycated hemoglobin (HBA1c) and blood lipid levels and hepatorenal functions of the patients were determined before and 12 weeks after the trial. Following the trial, the FBG, PPG, HbA1c, cholesterol (CHOL) and triglyceride (TG) levels in the vildagliptin group were significantly decreased compared with the pretreatment levels (P<0.05), whereas only the PPG level in the placebo group decreased (P<0.05). The FBG, PPG and HbA1c levels in the vildagliptin group were markedly lower than those in the placebo group 12 weeks after the trial. A comparison of the body weights and hepatorenal functions before and after the trial or between groups did not show statistically significant differences. The combination therapy of vildagliptin plus an α-glucosidase inhibitor effectively reduced the FBG, PPG and HbA1c levels in patients without inducing weight gain or hepatorenal dysfunction. However, the therapy may have caused a reduction in the blood lipid levels.

Risk factors for adverse symptoms during dipeptidyl peptidase-IV inhibitor therapy: a questionnaire-based study carried out by the Japan Pharmaceutical Association Drug Event Monitoring project in Kumamoto Prefecture

BACKGROUND

Meta-analyses of randomized clinical trials have reported that dipeptidyl peptidase IV (DPP-4) inhibitors are well tolerated and that the incidence of hypoglycemia with the use of DPP-4 inhibitors is similar to that observed with placebos. However, in general, provider-oriented methods using medical record reviews offer lower rates of non-serious, symptomatic adverse drug reactions (ADRs) than patient-oriented methods. Moreover, severe hypoglycemia occurred in three clinical trials using sitagliptin, but in two of these trials this phenomenon has been previously described only in the drug application data in the US.

OBJECTIVE

The aim of this study was to assess the profile of patient-reported symptomatic ADRs under DPP-4 inhibitor therapy and to detect risk factors for hypoglycemic and non-hypoglycemic adverse symptoms in daily clinical practice.

METHODS

We analyzed a subpopulation of participants in the Drug Event Monitoring (DEM) project of the Japan Pharmaceutical Association. An anonymous survey was conducted in February 2012 to assess the self-perception of adverse symptoms during a median 28 (4-88) days after the last prescription of DPP-4 inhibitors by means of interviews of pharmacists using structured questionnaires.

RESULTS

A total of 864 males and 686 females were included. The prescribed DPP-4 inhibitors included sitagliptin (75.4 %), alogliptin (15.5 %), vildagliptin (8.8 %) and linagliptin (0.3 %). Mild hypoglycemic symptoms were reported by 34 individuals (2.2 %) receiving monotherapy of sitagliptin (10/402) or alogliptin (3/65), or combination therapy of sitagliptin (15/767) or alogliptin (6/176) with other hypoglycemic agents. In the multiple regression model, hypoglycemic symptoms were found to be significantly associated with liver disease, female sex and alcohol consumption more than three times per week. Non-hypoglycemic symptoms were reported by 57 individuals (3.7 %), the most common symptoms of which were gastrointestinal symptoms (2.1 %). Combination therapy was only found to be associated with nonhypoglycemic symptoms.

CONCLUSIONS

The present study suggested that hypoglycemic symptoms under therapy with sitagliptin or alogliptin may be associated with liver disease, female sex and alcohol consumption, all of which are potentially capable of leading to poor gluconeogenesis because they decrease the counter-regulatory hormonal responses to hypoglycemia.

A randomized controlled clinical trial of vildagliptin plus metformin combination therapy in patients with type II diabetes mellitus

The aim of the present study was to assess the efficacy and safety of vildagliptin plus metformin combination therapy in patients with type II diabetes mellitus. Type II diabetic patients with poor glycemic control following at least three months of metformin treatment were selected and randomized into two groups. Vildagliptin or placebo was administered with metformin. Body weight, fasting blood glucose (FBG), postprandial glucose (PPG), glycated hemoglobin (HbA1c), blood lipid and hepatorenal function levels were analyzed in the patients prior to and 24-weeks after the trial. FBG, PPG and HbA1c levels of the patients in the vildagliptin group significantly decreased following the trial, whereas no statistically significant differences were observed in the various indicators of the placebo group prior to and following the trial. The FBG, PPG and HbA1c levels in the vildagliptin group were significantly lower compared with the placebo group 24-weeks after the trial. Comparisons of body weight, blood lipid and hepatorenal function between the groups prior to and following the trial exhibited no statistically significant differences. Therefore, vildagliptin plus metformin combination therapy effectively reduced FBG, PPG and HbA1c levels in patients with no risk of weight gain or hepatorenal dysfunction.

Probable linagliptin-induced liver toxicity: a case report

AIM

Unlike other dipeptidyl peptidase 4 (DPP-4) inhibitors, the excretion of linagliptin is mainly through a biliary route. Despite this fact, liver injury with linagliptin has thus far not been reported in the literature. However, this report describes the first case of probable linagliptin-induced liver toxicity.

METHODS

The clinical history, diagnosis, investigations and drug treatment of the patient are reviewed here.

RESULTS

A 58-year-old Japanese woman presented with fatigue, nausea, jaundice and marked elevations of hepatic enzymes 4weeks after starting linagliptin 5mg/day as monotherapy. No other medications were taken, and imaging studies revealed no other obvious causes of hepatic injury. Tests for viral serology and antinuclear antigen were negative. Symptoms disappeared and the levels of hepatic parameters (serum aminotransferases and biliary enzymes) slowly recovered after discontinuation of linagliptin. The slow recovery process may have been due to the very long half-life of the drug. The patient's Naranjo scale score was 6 and RUCAM score was 7.

CONCLUSION

Although linagliptin currently carries no liver warnings, it may be necessary to monitor hepatic function in some patients upon administration of this drug until further evidence is obtained.

Dipeptidyl peptidase-4 inhibitors in type 2 diabetes therapy--focus on alogliptin

Type 2 diabetes mellitus is a complex and progressive disease that is showing an apparently unstoppable increase worldwide. Although there is general agreement on the first-line use of metformin in most patients with type 2 diabetes, the ideal drug sequence after metformin failure is an area of increasing uncertainty. New treatment strategies target pancreatic islet dysfunction, in particular gut-derived incretin hormones. Inhibition of the enzyme dipeptidyl peptidase-4 (DPP-4) slows degradation of endogenous glucagon-like peptide-1 (GLP-1) and thereby enhances and prolongs the action of the endogenous incretin hormones. The five available DPP-4 inhibitors, also known as 'gliptins' (sitagliptin, vildagliptin, saxagliptin, linagliptin, alogliptin), are small molecules used orally with similar overall clinical efficacy and safety profiles in patients with type 2 diabetes. The main differences between the five gliptins on the market include: potency, target selectivity, oral bioavailability, long or short half-life, high or low binding to plasma proteins, metabolism, presence of active or inactive metabolites, excretion routes, dosage adjustment for renal and liver insufficiency, and potential drug-drug interactions. On average, treatment with gliptins is expected to produce a mean glycated hemoglobin (HbA1c) decrease of 0.5%-0.8%, with about 40% of diabetic subjects at target for the HbA1c goal <7%. There are very few studies comparing DPP-4 inhibitors. Alogliptin as monotherapy or added to metformin, pioglitazone, glibenclamide, voglibose, or insulin therapy significantly improves glycemic control compared with placebo in adult or elderly patients with inadequately controlled type 2 diabetes. In the EXAMINE trial, alogliptin is being compared with placebo on cardiovascular outcomes in approximately 5,400 patients with type 2 diabetes. In clinical studies, DPP-4 inhibitors were generally safe and well tolerated. However, there are limited data on their tolerability, due to their relatively recent marketing approval. Alogliptin will be used most when avoidance of hypoglycemic events is paramount, such as in patients with congestive heart failure, renal failure, and liver disease, and in the elderly.

Clinical utility of the dipeptidyl peptidase-4 inhibitor linagliptin

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors have emerged as new options in the management of type 2 diabetes mellitus, demonstrating meaningful antihyperglycemic effects and good tolerability profiles. Glycemic control is improved by preventing the DPP-4-mediated degradation of incretin hormones, with a resulting increase in insulin secretion and inhibition of glucagon secretion.

PURPOSE

This article provides a discussion of the clinical utility of linagliptin.

RESULTS AND CONCLUSION

Linagliptin is a xanthine-based, oral DPP-4 inhibitor that has been approved in the United States and Europe. It has been evaluated extensively in clinical trials, and results in improved glycemic control when used as monotherapy, initial combination therapy with metformin or pioglitazone, add-on therapy to metformin and/or a sulfonylurea, or add-on therapy to basal insulin (with or without oral antidiabetic drugs). Consistent with other members of its class, the benefits of linagliptin also include a low risk of hypoglycemia and weight gain. However, linagliptin is the first DPP-4 inhibitor to be approved as a once-daily, 5-mg dose and, due to its primarily non-renal route of excretion, no dosage adjustment is required for patients with renal or hepatic impairment. The pharmacokinetics and pharmacodynamics of linagliptin are not affected to a clinically meaningful degree by race or ethnicity and linagliptin has very low potential for drug-drug interactions.

Physiologic and weight-focused treatment strategies for managing type 2 diabetes mellitus: the metformin, glucagon-like peptide-1 receptor agonist, and insulin (MGI) approach

The prevalence of type 2 diabetes mellitus (T2DM) is rising in association with an increase in obesity rates. Current treatment options for patients with T2DM include lifestyle modifications and numerous antidiabetic medications. Despite the availability of effective and well-tolerated treatments, many patients do not achieve recommended glycemic targets. Lack of efficacy is complicated by the wide range of available agents and little specificity in treatment guidelines, thus challenging clinicians to understand the relative benefits and risks of individual options for each patient. In this article, lifestyle intervention strategies and current antidiabetic agents are evaluated for their efficacy, safety, and weight-loss potential. Because of the heterogeneous and progressive nature of T2DM, physicians should advocate approaches that emphasize weight management, limit the risk of hypoglycemia and adverse events, and focus on the core pathophysiologic defects in patients with T2DM. A healthy, plant-based diet that is low in saturated fat and refined carbohydrates but high in whole grains, vegetables, legumes, and fruits, coupled with resistance and aerobic exercise regimens, are recommended for patients with T2DM. When necessary, drug intervention, described in this article as the MGI (metformin, glucagon-like peptide-1 receptor agonist, and insulin) approach, should begin with metformin and progress to the early addition of glucagon-like peptide-1 receptor agonists because of their weight loss potential and ability to target multiple pathophysiologic defects in patients with T2DM. For most patients, treatments that induce weight gain and hypoglycemia should be avoided. Long-acting insulin should be initiated if glycemic control is not achieved with metformin and glucagon-like peptide-1 receptor agonist combination therapy, focusing on long-acting insulin analogs that induce the least weight gain and have the lowest hypoglycemic risk. Ultimately, a patient-centered treatment approach that addresses the core pathologies of T2DM and obesity will not only increase overall efficacy and the likelihood that a patient adheres to treatment, but may also improve a patient's mental well-being and quality of life.

Association of musculoskeletal complaints and gliptin use: review of spontaneous reports

PURPOSE

Gliptins are new oral antidiabetic drugs that increase insulin levels through dipeptidyl peptidase-4 inhibition. Recently, the association of serious musculoskeletal (MSk) adverse effects with the gliptin use has been suggested. The aim is to describe and analyze the characteristics of spontaneous reports related to these adverse effects and gliptin use.

METHODS

All spontaneous reports with MSk disorders associated with gliptins gathered in the Spanish pharmacovigilance database until May 2012 were described and analyzed using a case/non-case method.

RESULTS

Gliptins were reported as the suspected drug in 332 cases: 208 involved sitagliptin, 115 vildagliptin, and nine saxagliptin. In 34 patients (10.2% of total reports with gliptins), MSk reactions were described (22 women [64.7%] and 12 men [35.3%]). Their mean age was 65.1 years; 41.2% were younger than 65 years. Only seven cases were serious, but the gliptin had to be withdrawn in 22 patients because of intolerance and/or persistence of MSk discomfort, and patients recovered after its discontinuation. A positive re-challenge was observed in two cases. In seven cases, the patients were on previous chronic treatment with statins, and began to present MSk complaints shortly after starting a gliptin. The reporting odds ratio (ROR) for myalgia and arthralgia were strongly associated with gliptin use (ROR 1.96 [95% CI 1.12-3.43], p < 0.05 and ROR 2.69 [95% CI 1.38-5.24], p < 0.05, respectively).

CONCLUSIONS

Musculoskeletal disorders are adverse reactions strongly associated with gliptins that, despite not being serious, may impair the treatment adherence in patients with type 2 diabetes. Future observational studies could confirm these findings.

Gliptins (dipeptidyl peptidase-4 inhibitors) and risk of acute pancreatitis

INTRODUCTION

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) play an increasing role in the management of type 2 diabetes. Such incretin-based therapies offer some advantages over other glucose-lowering agents, but might be associated with an increased risk of acute pancreatitis.

AREAS COVERED

An extensive literature search was performed to analyze clinical cases of acute pancreatitis reported in the literature or to the Food and Drug Administration (FDA), in randomized clinical trials, and in observational studies with five DPP-4 inhibitors: sitagliptin, vildagliptin, saxagliptin, alogliptin, and linagliptin.

EXPERT OPINION

An increased risk of pancreatitis has been reported in diabetic versus nondiabetic patients. Several anecdotal clinical cases of pancreatitis have been reported with sitagliptin and vildagliptin and an increased relative risk reported to the FDA with sitagliptin versus other comparators, but reporting bias cannot be excluded. In rather short-term clinical trials with well-selected diabetic patients, no increased risk of acute pancreatitis has been observed with any of the five commercialized DPP-4 inhibitors: sitagliptin, vildagliptin, saxagliptin, alogliptin, and linagliptin. Similarly, real-life cohort studies showed no increased incidence of pancreatitis with gliptins compared with other glucose-lowering agents, a finding recently challenged by a case- control study. These results must be confirmed in postmarketing surveillance programs and in ongoing large prospective trials with cardiovascular outcomes.

Long-term safety of linagliptin monotherapy in Japanese patients with type 2 diabetes

AIMS

In a phase III study conducted among Japanese patients with type 2 diabetes mellitus (T2DM), linagliptin 5 and 10 mg showed clinically meaningful improvements in glycaemic parameters after 12 and 26 weeks compared with placebo and voglibose, respectively. This extension study assessed long-term tolerability of linagliptin over 52 weeks.

METHODS

Japanese patients with T2DM who completed either phase of a 12-week/26-week study comparing linagliptin monotherapy with placebo or voglibose were eligible to enrol. In the extension study, the comparator groups switched to linagliptin 5 or 10 mg, while the linagliptin groups maintained dosage.

RESULTS

In all, 540 patients received at least one dose of linagliptin 5 or 10 mg and 494 completed the extension. Long-term treatment with linagliptin was well tolerated; adverse events (AEs) of special interest and serious AEs occurred in small percentages of patients. Drug-related AEs occurred in 10.2 and 10.6% of patients in the linagliptin 5- and 10-mg groups, respectively, and discontinuations due to drug-related AEs occurred in 1.1 and 0.7%, respectively. Only one (0.4%) patient in each dose group experienced investigator-defined hypoglycaemia during the treatment period (both events were non-severe). Body weight was not clinically altered in either group. The glycated haemoglobin A1c profiles over time were similar with linagliptin 5 and 10 mg.

CONCLUSIONS

These findings provide evidence for the safety and tolerability of oral linagliptin at either 5 or 10 mg for up to 52 weeks for the treatment of Japanese patients with T2DM, without clinically relevant increase in the risk of hypoglycaemia or weight gain.

Treatment persistence, hypoglycaemia and clinical outcomes in type 2 diabetes patients with dipeptidyl peptidase-4 inhibitors and sulphonylureas: a primary care database analysis

AIMS

To investigate therapy persistence, frequency of hypoglycaemia and macrovascular outcomes among type 2 diabetes patients with dipeptidyl peptidase-4 (DPP-4) inhibitors (DPP-4) and sulphonylureas (SU).

METHODS

Data from 19,184 DPP-4 (mean age: 64 years; 56% males) and 31,110 SU users (69 years; 51%) with new prescriptions (index date), without additional antidiabetics except metformin, in 1201 general practises in Germany were analysed. Therapy discontinuation (prescription gap >90 days), hypoglycaemia [International Classification of Diseases (ICD-10)] and macrovascular outcomes (ICD-10) (2-year follow-up) were compared adjusting for age, sex, diabetes duration, metformin, previous hypoglycaemia, health insurance, hypertension, hyperlipidaemia, antihypertensives, lipid-lowering and antithrombotic drugs, microvascular complications and Charlson co-morbidity score using logistic or Cox regression models.

RESULTS

Two years after index date, DDP-4 (non-persistence: 39%) were associated with a lower risk of discontinuation compared to SU (49%) [adjusted hazard ratio (HR): 0.74; 95% confidence interval (CI): 0.71-0.76]. Hypoglycaemias (≥1) were documented in 0.18% patients with DPP-4 and in 1.00% with SU [odds ratio (OR): 0.21; 95%CI: 0.08-0.57]. Hypoglycaemias were significantly associated with incident macrovascular complications (HR: 1.6; 95% CI: 1.1-2.2). Risk of macrovascular events was 26% lower in DPP-4 than in SU users.

CONCLUSIONS

Lack of persistence with antidiabetic therapy is frequently found in primary care patients. DPP-4 was associated with lower therapy discontinuation and a fivefold reduced frequency of patients with hypoglycaemia compared to SU. The low absolute numbers of hypoglycaemias are most likely due to the fact that only severe events were documented. DPP-4 treatment was associated with reduced incidence of macrovascular events relative to SU in type 2 diabetes patients in primary care practises.

Clinical overview of linagliptin, a dipeptidyl peptidase-4 inhibitor, in patients with Type 2 diabetes mellitus

Linagliptin is a pharmacologically unique, orally active, once-daily dipeptidyl peptidase-4 inhibitor indicated for the treatment of hyperglycemia in patients with Type 2 diabetes mellitus. Compared with other dipeptidyl peptidase-4 inhibitors, linagliptin has a favorable pharmacokinetic profile with a primarily nonrenal route of elimination that avoids the need for dose adjustment in patients with renal impairment. When administered as monotherapy or in combination with other antihyperglycemic drugs, linagliptin treatment leads to clinically meaningful reductions in glycated hemoglobin, fasting plasma glucose and postprandial plasma glucose levels. In addition, pancreatic β-cell function is enhanced. Linagliptin treatment is well tolerated, with weight-neutral effects and no increased risk of hypoglycemia. Of note, linagliptin treatment was associated with a significantly reduced risk of cardiovascular events in clinical trials of ≤2 years, although this finding remains to be confirmed in larger and longer clinical outcomes studies.