Clinical Safety and Tolerability of Vildagliptin - Insights from Randomised Trials, Observational Studies and Post-marketing Surveillance

Mitigating iftar-related glycemic excursions in adolescents and young adults with type 1 diabetes on MiniMed™ 780G advanced hybrid closed loop system: a randomized clinical trial for adjunctive oral vildagliptin therapy during Ramadan fasting

BACKGROUND

Ramadan Iftar meal typically causes glucose excursions. Dipeptidyl peptidase-4 inhibitors increase glucagon-like peptide-1 and thus, decrease blood glucose levels with low risk of hypoglycemia.

AIM

To investigate the efficacy and safety of vildagliptin as an add-on therapy on glucose excursions of Iftar Ramadan meals among adolescents and young adults with type 1 diabetes mellitus (T1DM) using advanced hybrid closed-loop (AHCL) treatment.

METHODS

Fifty T1DM patients on MiniMed™ 780G AHCL were randomly assigned either to receive vildagliptin (50 mg tablet) with iftar meal during Ramadan month or not. All participants received pre-meal insulin bolus based on insulin-to-carbohydrate ratio (ICR) for each meal constitution.

RESULTS

Vildagliptin offered blunting of post-meal glucose surges (mean difference - 30.3 mg/dL [- 1.7 mmol/L] versus - 2.9 mg/dL [- 0.2 mmol/L] in control group; p < 0.001) together with concomitant exceptional euglycemia with time in range (TIR) significantly increased at end of Ramadan in intervention group from 77.8 ± 9.6% to 84.7 ± 8.3% (p = 0.016) and time above range (180-250 mg/dL) decreased from 13.6 ± 5.1% to 9.7 ± 3.6% (p = 0.003) without increasing hypoglycemia. A significant reduction was observed in automated daily correction boluses and total bolus dose by 23.9% and 16.3% (p = 0.015 and p < 0.023, respectively) with less aggressive ICR settings within intervention group at end of Ramadan. Coefficient of variation was improved from 37.0 ± 9.4% to 31.8 ± 7.1%; p = 0.035). No severe hypoglycemia or diabetic ketoacidosis were reported.

CONCLUSION

Adjunctive vildagliptin treatment mitigated postprandial hyperglycemia compared with pre-meal bolus alone. Vildagliptin significantly increased TIR while reducing glycemic variability without compromising safety. Trial registration This trial was registered under ClinicalTrials.gov Identifier no. NCT06021119.

A systematic review on the clinical pharmacokinetics of vildagliptin in healthy and disease populations

INTRODUCTION

Vildagliptin, a dipeptidyl peptidase-4 inhibitor, is indicated to cure type 2 diabetes mellitus (T2DM). This systematic literature search aims to assess the current knowledge about the clinical pharmacokinetics (PK) of vildagliptin to provide recommendations for clinical use to prevent the harmful effects of this drug.

METHODS

The PubMed, Science Direct, EBSCO, Cochrane Central Register of Controlled Trials, and Google Scholar databases were screened for articles related to the clinical PK of vildagliptin using systematic search strategies.

RESULTS

The literature search identified 2118 records, among which 28 were subsumed in this systematic review that fulfilled the inclusion standards.

CONCLUSIONS

This systematic review can help dose optimization among critically ill patients (e.g. renal impairment) without exposing them to the drug's toxic effects.

Efficacy and Safety of a Fixed-Dose Combination of Vildagliptin and Pioglitazone in Indian Patients With Type 2 Diabetes Mellitus: A Randomized, Open-Label, Comparative, Phase III Study

Background Type 2 diabetes mellitus (T2DM) arises due to a range of pathological abnormalities, necessitating a combination therapy to achieve optimal glycemic control. Vildagliptin, an effective and selective DPP-4 inhibitor, and pioglitazone, an insulin sensitizer, offer distinct mechanisms of action. Hence, the integration of these medications represents a logical and justified therapeutic strategy Objective To compare the efficacy, safety, and tolerability of vildagliptin and pioglitazone 50 mg/15 mg fixed-dose combination (FDC) tablets with individual monotherapy vildagliptin 50 mg and pioglitazone 15 mg tablets in Indian T2DM patients who were inadequately controlled on metformin monotherapy. Methods This was a randomized, open-label, comparative, multicenter, phase III study involving 195 T2DM patients with inadequate glycemic control on metformin ≥ 1000 mg/day. Patients were randomly assigned in a 1:1:1 ratio to the test product group (n=65) (vildagliptin 50 mg + pioglitazone 15 mg FDC tablets), reference product group 1 (n=65) (vildagliptin 50 mg tablet), or reference product group 2 (n=65) (pioglitazone 15 mg tablet reference product). The primary endpoint was the mean change in HbA1c levels from baseline to end of the study visit (12 weeks (84 days ±2)). The secondary endpoints were the mean change in fasting plasma glucose (FPG) and 2-hr postprandial plasma glucose (2-hr PPG) levels. Safety parameters were assessed till the end of the study. Results A total of 178 patients completed the study. At 12 weeks, the mean HbA1c level in the test group reduced to 6.85 ± 1.27%, in the reference product 1 group to 7.56 ± 1.72%, and in the reference product 2 groups to 7.37 ± 1.59%. The mean change in Hb1Ac from baseline in the test group was statistically significant compared to the reference groups (p=0.037). Similarly, the mean changes in the FPG and 2hr-PPG with the test product were statistically significant compared to reference products (p=0.041). The adverse events were comparable across all the treatment groups. Conclusion In Indian T2DM patients inadequately controlled on a daily maximum dose of metformin, treatment with vildagliptin and pioglitazone FDC showed better glycemic control than either vildagliptin or pioglitazone along with a good tolerability profile.

Sustained-Release Vildagliptin 100 mg in Type 2 Diabetes Mellitus: A Review

Dipeptidyl peptidase-4 inhibitors (DPP4Is) were introduced into the management of type 2 diabetes mellitus (T2DM) as they are insulinotropic and have no inherent risk of hypoglycemia and no effect on body weight. Currently, 11 drugs in this class are available for the management of diabetes. Although they have a similar mechanism of action, they differ from one other in their binding mechanisms, which influences their therapeutic and pharmacological profiles. Vildagliptin's overall safety and tolerability profile was comparable to placebo throughout clinical studies, and real-world data in a large group of T2DM patients corroborated this finding. Therefore, DPP4Is like vildagliptin is a secure alternative for treating patients with T2DM. Vildagliptin treatment given as a once-daily (QD) 100 mg sustained release (SR) formulation fits the criteria of adherence and compliance. This SR formulation, given once daily has the potential to provide glycemic control like the vildagliptin 50 mg twice-daily (BD) formulation. This comprehensive review discusses the journey of vildagliptin as 50 mg BD therapy as well as 100 mg SR QD therapy.

A Comprehensive Review on Weight Loss Associated with Anti-Diabetic Medications

Obesity is a complex metabolic condition that can have a negative impact on one's health and even result in mortality. The management of obesity has been addressed in a number of ways, including lifestyle changes, medication using appetite suppressants and thermogenics, and bariatric surgery for individuals who are severely obese. Liraglutide and semaglutide are two of the five Food and Drug Administration (FDA)-approved anti-obesity drugs that are FDA-approved agents for the treatment of type 2 diabetes mellitus (T2DM) patients. In order to highlight the positive effects of these drugs as anti-obesity treatments, we analyzed the weight loss effects of T2DM agents that have demonstrated weight loss effects in this study by evaluating clinical studies that were published for each agent. Many clinical studies have revealed that some antihyperglycemic medications can help people lose weight, while others either cause weight gain or neutral results. Acarbose has mild weight loss effects and metformin and sodium-dependent glucose cotransporter proteins-2 (SGLT-2) inhibitors have modest weight loss effects; however, some glucagon-like peptide-1 (GLP-1) receptor agonists had the greatest impact on weight loss. Dipeptidyl peptidase 4 (DPP-4) inhibitors showed a neutral or mild weight loss effect. To sum up, some of the GLP-1 agonist drugs show promise as weight-loss treatments.

Case Report: Rhabdomyolysis secondary to vildagliptin overdose in a suicidal attempt: A case report and brief literature review

Rhabdomyolysis is a life-threatening syndrome associated with direct or indirect muscle damage that is rarely reported with dipeptidyl peptidase (DPP)-4 inhibitors. Here we presented a case in which a 58-year-old female suffered from severe swelling and pain in bilateral lower limbs and oliguria after a suicidal vildagliptin overdose. Drug-induced rhabdomyolysis and drug-induced liver injury were diagnosed based on laboratory and radiological findings. The patient was treated with fluid resuscitation, insulin, electrolyte replacement, diuretics, urine alkalizing agents, anticoagulants, antioxidants, and 24-h bedside ECG monitoring and suicide prevention. After 20 days of hospitalization and close monitoring, the patient was discharged without sequelae. Risk factors, diagnostic criteria, disease mechanisms, and outcomes were also discussed. This case illustrated that overdose of oral anti-diabetic medications may result in clinically significant adverse events, such as rhabdomyolysis in this case with a DPP-4 inhibitor. Although the incidence is low, special attention should be paid to intentional or accidental exposure to anti-diabetic medications during suicide attempts, especially in depressed patients with diabetes.

A review on network pharmacology based phytotherapy in treating diabetes- An environmental perspective

Diabetes has become common lifestyle disorder associated with obesity and cardiovascular diseases. Environmental factors like physical inactivity, polluted surroundings and unhealthy dieting also plays a vital role in diabetes pathogenesis. As the current anti-diabetic drugs possess unprecedented side effects, traditional herbal medicine can be used an alternative therapy. The paramount challenge with the herbal formulation usage is the lack of standardized procedure, entangled with little knowledge on drug safety and mechanism of drug action. Heavy metal contamination is a major environmental hazard where plants tend to accumulate toxic metals like nickel, chromium and lead through industrial and agricultural activities. It becomes inappropriate to use these plants for phytotherapy as it may affect the human health on long term consumption. This review discuss about the environmental risk factors related to diabetes and better implication of medicinal plants in anti-diabetic therapy using network pharmacology. It is an in silico analytical tool that helps to unravel the multi-targeted action of herbal formulations rich in secondary metabolites. Also, a special focus is attempted to pool the databases regarding the medicinal plants for diabetes and associated diseases, their bioactive compounds, possible diabetic targets, drug-target interaction and toxicology reports that may open an aisle in safer, effective and toxicity-free drug discovery.

Exploring early combination strategy in Latin American patients with newly diagnosed type 2 diabetes: a sub-analysis of the VERIFY study

BACKGROUND

Patients with type 2 diabetes mellitus (T2DM) from Latin American countries face challenges in access to healthcare, leading to under-diagnosis, under-achievement of glycemic target, and long-term complications. Early diagnosis and treatment initiation are of paramount importance in this population due to the high prevalence of risk factors such as obesity and metabolic syndrome. The VERIFY study in patients with newly diagnosed T2DM (across 34 countries), assessed the normoglycemic durability (5 years), with early combination (EC) therapy approach versus the traditional stepwise approach of initiating treatment with metformin monotherapy (MET). Here we present the results from the VERIFY study for participants from eight countries in Latin America.

METHODS

Newly diagnosed adult patients with T2DM, HbA1c 6.5-7.5% and body-mass index (BMI) of 22-40 kg/m² were enrolled. The primary endpoint was time to initial treatment failure (TF; HbA1c ≥ 7.0% at two consecutive scheduled visits 13 weeks apart). Time to second TF was evaluated when patients in both groups were receiving and failing on the vildagliptin combination. Safety and tolerability were also assessed for both treatment approaches during the study.

RESULTS

A total of 537 eligible patients (female, 58.8%) were randomly assigned to receive either EC (n = 266) or MET (n = 271). EC significantly reduced the relative risk of time to initial TF by 47% versus MET [HR (95% CI) 0.53 (0.4, 0.7) p < 0.0001]. Overall, 46.4% versus 66.3% of patients achieved the primary endpoint in the EC and MET groups, with a median [interquartile range (IQR)] time to TF of 59.8 (27.5, not evaluable) and 33.4 (12.2, 60.1) months, respectively. The risk for time to second TF was 31% lower with EC (p < 0.0092). A higher proportion of patients receiving EC maintained durable HbA1c < 7.0%, < 6.5%, and < 6.0%. Both treatment approaches were well tolerated, and only 3.2% of participants discontinued the study due to adverse events. All hypoglycemic events (EC: n = 7 and MET: n = 3) were single, mild episodes and did not lead to study discontinuation.

CONCLUSION

Similar to the global population, long-term clinical benefits were achieved more frequently and without tolerability issues with EC versus standard-of-care MET in this Latin American sub-population. This study is registered with ClinicalTrials.gov, NCT01528254.

Protective roles of thymoquinone and vildagliptin in manganese-induced nephrotoxicity in adult albino rats

Despite being important in the body's mechanisms, excessive accumulation of manganese (Mn) can induce severe toxicity in vital organs of the body. Thymoquinone (TQ) is extracted from Nigella sativa seeds which recently gained popularity as dietary supplements and plant-based antioxidants. Vildagliptin (VLD) is a dipeptidyl peptidase IV (DPPIV) inhibitor, approved as anti-hyperglycemic agents with cardioprotective and renoprotective effects. The present study aimed to investigate the nephrotoxicity of Mn and the potential protective effects of thymoquinone and vildagliptin. Sixty-four adult male albino rats were equally divided into 8 groups: group I (control, received no medication), group II (vehicle, received normal saline), group III (TQ, 50 mg/kg/day), group IV (VLD, 10 mg/kg/day), group V (MnCl₂, 50 mg/kg/day), group VI (Mn+TQ), group VII (Mn+VLD), and group VIII (Mn+TQ+VLD). Groups VI, VII, and VIII, received the same previously mentioned doses. All drugs were orally gavaged for 12 weeks. Manganese administration resulted in an elevation in the levels of serum and tissues Mn, blood glucose, serum urea, creatinine, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and reduction in insulin, kidney superoxide dismutase (SOD), glutathione (GSH), and interleukin-10. Histopathological structural renal damage was detected associated with strong positive immunoexpression of caspase-3. On the other hand, individual or combined TQ and VLD administration with Mn significantly decreased the serum and tissue levels of Mn, declined the blood glucose, inflammatory markers, oxidative stress markers, ameliorated the histopathological effects, and down-regulated the immunoexpression of caspase-3. In conclusion, TQ and VLD co-administration elicited protective effects against Mn-induced nephrotoxicity.

Efficacy of a Combination of Metformin and Vildagliptin in Comparison to Metformin Alone in Type 2 Diabetes Mellitus: A Multicentre, Retrospective, Real-World Evidence Study

BACKGROUND

Early use of combination therapy in diabetes patients may lead to sustained glycemic control and thereby reduce the progression of diabetic complications. Given the limitation of the traditional stepwise intensification strategy, early combination therapy can be an effective approach. Therefore, this study aims to assess the real-world efficacy of a combination of metformin and vildagliptin in comparison to metformin alone in type 2 diabetes mellitus (T2DM) patients in India.

METHODS

This was an observational, retrospective, non-interventional study based on electronic medical records (EMRs) of 2740 T2DM patients, retrieved from 2010 onwards from 22 diabetes centres across India. Adult drug naïve patients with a 5-year history of T2DM treated with either metformin or a combination of metformin and vildagliptin for at least 3 months were considered for this study. Efficacy assessment was done to evaluate the post-treatment HbA1c levels and patients requiring additional oral antidiabetic drugs (OADs) at the time of follow-up visit. Patients were also analyzed for the occurrence of adverse events.

RESULTS

Out of the total, 2452 patients were in metformin only arm, and 288 patients were in metformin plus vildagliptin treatment arm. A more significant reduction in HbA1c level was observed in metformin plus vildagliptin arm than metformin only arm (median: -0.5% vs 0%, respectively; p<0.001). Patients requiring additional OAD at follow-up were significantly lesser in the metformin plus vildagliptin arm than the metformin only arm (15.6% vs 35.2%, respectively; p<0.001). The adverse events were comparable across the two arms, and commonly reported adverse events were giddiness, fatigue and gastric discomfort.

CONCLUSION

The findings of this EMR-based real-world study emphasizes the need for early initiation of combination therapy (metformin plus vildagliptin) over metformin monotherapy for achieving better glycemic control.

Evaluating the Evidence behind the Novel Strategy of Early Combination from Vision to Implementation

Type 2 diabetes mellitus (T2DM) is a complex and progressive chronic disease characterised by elevating hyperglycaemia and associated need to gradually intensify therapy in order to achieve and maintain glycaemic control. Treating hyperglycaemia with sequential therapy is proposed to allow holistic assessment of the efficacy and risk-to-benefit ratio of each added component. However, there is an array of evidence supporting the scientific rationale for using synergistic, earlier, modern drug combinations to achieve glycaemic goals, delay the deterioration of glycaemic control, and, therefore, potentially preserve or slow down the declining β-cell function. Additionally, implementation of early combination(s) may lead to opportunities to combat clinical inertia and other hurdles to optimised disease management outcomes. This review aims to discuss the latest empirical evidence for long-term clinical benefits of this novel strategy of early combination in people with newly diagnosed T2DM versus the current widely-implemented treatment paradigm, which focuses on control of hyperglycaemia using lifestyle interventions followed by sequentially intensified (mostly metformin-based) monotherapy. The recent reported Vildagliptin Efficacy in combination with metfoRmin For earlY treatment of T2DM (VERIFY) study results have provided significant new evidence confirming long-term glycaemic durability and tolerability of a specific early combination in the management of newly diagnosed, treatment-naïve patients worldwide. These results have also contributed to changes in clinical treatment guidelines and standards of care while clinical implementation and individualised treatment decisions based on VERIFY results might face barriers beyond the existing scientific evidence.

A pre-specified statistical analysis plan for the VERIFY study: Vildagliptin efficacy in combination with metformin for early treatment of T2DM

AIMS

To ensure the integrity of the planned analyses and maximize the clinical utility of the VERIFY study results by describing the detailed concepts behind its statistical analysis plan (SAP) before completion of data collection and study database lock. The SAP will be adhered to for the final primary data analysis of the VERIFY trial.

MATERIALS AND METHODS

Vildagliptin efficacy in combination with metformin for early treatment of T2DM (VERIFY) is an ongoing, multicentre, randomized controlled trial aiming to demonstrate the clinical benefits of glycaemic durability and glucose control achieved with an early combination therapy in newly-diagnosed type 2 diabetes (T2DM) patients.

RESULTS

The SAP was initially designed at the study protocol conception phase and later modified, as reported here, in collaboration between the steering committee members, statisticians, and the VERIFY study leadership team. All authors were blinded to treatment allocation. An independent statistician has additionally retrieved and presented unblinded data to the independent data safety monitoring committee. An overview of the trial design with a focus on describing the fine-tuning of the analysis plan for the primary efficacy endpoint, risk of initial treatment failure, and secondary, exploratory and pre-specified subgroup analyses is provided here.

CONCLUSION

According to optimal trial practice, the details of the statistical analysis and data-handling plan prior to locking the database are reported here. The SAP accords with high-quality standards of internal validity to minimize analysis bias and will enhance the utility of the reported results for improved outcomes in the management of T2DM.

Association between vildagliptin and risk of angioedema, foot ulcers, skin lesions, hepatic toxicity, and serious infections in patients with type 2 diabetes mellitus: A European multidatabase, noninterventional, postauthorization safety study

OBJECTIVES

This noninterventional, multidatabase, analytical cohort study explored whether vildagliptin is associated with an increased risk of specific safety events of interest, namely angioedema, foot ulcers, or skin lesions, adverse hepatic events, or serious infections compared with other noninsulin antidiabetic drugs (NIADs) using real-world data from five European electronic healthcare databases.

DESIGN

Patients with type 2 diabetes mellitus aged ≥18 years on NIAD treatment were included between January 2005 and June 2014. Adjusted incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for the outcomes of interest were estimated using negative binomial regression.

PATIENTS

Approximately 2.8% of the included patients (n = 738 054) used vildagliptin at any time during the study, with an average follow-up time of 1.4 years.

RESULTS

The adjusted IRRs (vildagliptin vs. other NIADs) were in the range of 0.87-3.71 (angioedema), 0.73-1.19 (foot ulcers), 0.37-1.18 (skin lesions), 0.24-1.14 (composite of foot ulcer or skin lesions), 0.29-0.55 (serious hepatic events), and 0.59-1.04 (serious infections), with no lower bound of the 95% CIs > 1.

CONCLUSIONS

Overall, there was no increased risk of the events of interest in association with vildagliptin use compared with other NIADs.

Ten years of experience with DPP-4 inhibitors for the treatment of type 2 diabetes mellitus

Achieving and maintaining recommended glycemic targets without causing adverse e ffects, including hypoglycemia, is challenging, especially in older patients with type 2 diabetes mellitus (T2DM). The introduction of dipeptidyl peptidase-4 (DPP-4) inhibitors, more than 10 years ago, has provided an alternative to conventional medications for the intensification of glucose-lowering treatment after failure of metformin monotherapy, and therefore, marked an important advance in the management of T2DM. By prolonging the activity of incretin hormones, DPP-4 inhibitors induce insulin release and decrease glucagon secretion in a glucose-dependent manner. This results in a more physiologic glycemic control as compared to that ensured by insulin secretagogues (sulfonylureas and glinides). Overall, DPP-4 inhibitors have a favorable safety profile and can be used without dose adjustments in older adults and in patients with mild renal impairment; they have a neutral effect on body weight and do not cause hypoglycemia by themselves. Safety issues, reported mainly in post-marketing surveillance programs and including cardiovascular outcomes and the risk of acute pancreatitis, are being extensively investigated. The aim of this review is to discuss the impact of DPP-4 inhibitors on the treatment of T2DM, after 10 years of experience, with an emphasis on diabetes care in Italy. We will first describe T2DM treatment in Italy and then provide an overview of the main findings from randomized controlled trials, real-world studies and post-marketing surveillance programs with DPP-4 inhibitors.

Identification of Novel Metabolites of Vildagliptin in Rats: Thiazoline-Containing Thiol Adducts Formed via Cysteine or Glutathione Conjugation

Vildagliptin (VG), a dipeptidyl peptidase-4 inhibitor, is used for treating type 2 diabetes. On rare occasions, VG causes liver injury as an adverse reaction. One case report suggested the involvement of immune responses in the hepatotoxicity, but the underlying mechanisms are unknown. We recently reported that VG binds covalently in vitro to l-cysteine to produce a thiazoline acid metabolite, M407, implying that the covalent binding may trigger the immune-mediated hepatotoxicity. There was no evidence, however, that such a thiazoline acid metabolite was formed in vivo. In the present study, we administered a single oral dose of VG to male Sprague-Dawley rats, and detected M407 in plasma. The sum of urinary and fecal excretions of M407 reached approximately 2% of the dose 48 hours postdosing. Using bile duct-cannulated rats, we demonstrated that M407 was secreted into bile as a glucuronide, designated as M583. Another newly identified thiazoline metabolite of VG, the cysteinylglycine conjugate M464, was detected in urine, feces, and bile. The formation of M464 was confirmed by in vitro incubation of VG with glutathione even in the absence of metabolic enzymes. A glutathione adduct against the nitrile moiety M611 was also detected in vitro but not in vivo. In summary, we found three new thiazoline-containing thiol adduct metabolites in VG-administered rats. Nonenzymatic covalent binding of VG would likely occur in humans, and it may be relevant to predicting adverse reactions.

Pancreatic safety of vildagliptin in patients with type 2 diabetes mellitus: A European, noninterventional, postauthorization safety study

This cohort study assessed the pancreatic safety of vildagliptin versus other noninsulin antidiabetic drugs (NIADs) based on data from five European electronic health care databases. Patients with type 2 diabetes aged ≥18 years on NIAD treatment were enrolled. Adjusted incidence rate ratios (IRRs) and 95% confidence intervals (CIs) were estimated separately for acute pancreatitis and pancreatic cancer for vildagliptin (± other NIADs) compared with other NIADs using negative binomial regression. Approximately 2.8% of the enrolled patients (n = 738 054) used vildagliptin during the study, with an average follow-up time of 1.4 years. For acute pancreatitis, adjusted IRRs ranged between 0.89 andt 2.58 with all corresponding 95% CIs crossing 1. For pancreatic cancer adjusted IRRs ranged from 0.56 to 3.64, with the lower limit of 95% CIs >1 in some analyses. Post hoc sensitivity analyses taking latency time into account markedly lowered the risk estimates with corresponding 95% CIs crossing 1. Overall, the results do not suggest an increased pancreatitis risk with vildagliptin, while the observation for pancreatic cancer have to be interpreted carefully as this study was not designed to assess pancreatic cancer and rather be explained by certain underlying limitations including latency -time, chance findings and/or bias and confounding.

Relationship of patient background with macro- and microvascular complications: a 2-year post-marketing surveillance of vildagliptin in nearly 20,000 Japanese diabetic patients

BACKGROUND

Vildagliptin is indicated for type 2 diabetes mellitus (T2DM); however, the onset and exacerbation of diabetic complications in Japanese T2DM patients treated with vildagliptin is unknown.

RESEARCH DESIGN AND METHODS

This 2-year post-marketing surveillance (PMS) assessed the real-world safety and efficacy of vildagliptin therapy in 19,218 Japanese T2DM patients. The relationship between the incidence of macro- and microvascular complications with patient characteristics and changes in glycemic control (HbA1c) were evaluated.

RESULTS

The incidences of macro- and microvascular diseases were 1.14% and 3.09%, respectively. Patients with HbA1c ≥8.4% had a higher odds ratio (OR) for micro- and macrovascular disease (OR: 2.02 and 1.90) compared with patients with HbA1c <6.9%. Patient characteristics (OR, 95% CI) associated with macrovascular disease were age (1.04, 1.01-1.07) and a history of macrovascular disease (3.38, 1.98-5.75). Microvascular disease was associated with a final HbA1c level ≥7.0% (1.48, 1.11-1.98) and previous diabetic nephropathy (1.42, 1.05-1.93). The mean (SD) HbA1c decreased from 7.89% (1.46%) to 7.05% (0.99%) after 24 months.

CONCLUSIONS

Vildagliptin elicited no increases/exacerbations of diabetic complications; this PMS suggested that the incidence of diabetic complications tends to be low in subjects with good HbA1c control.

THE IN VITRO CYTOTOXICITY, GENOTOXICITY AND OXIDATIVE DAMAGE POTENTIAL OF THE ORAL DIPEPTIDYL PEPTIDASE-4 INHIBITOR, LINAGLIPTIN, ON CULTURED HUMAN MONONUCLEAR BLOOD CELLS

BACKGROUND

Linagliptin (LNG) is a selective dipeptidyl peptidase-4 (DPP-4) inhibitor that ameliorates blood glucose control of patients with type 2 diabetes, without developing hypoglycemic risk and weight gain with a good clinical and biological tolerance profile. To the best of our knowledge, its cytotoxic, genotoxic and oxidative effects have never been studied on any cell line.

AIM

To evaluate the in vitro cytotoxic, genotoxic damage potential and antioxidant/oxidant activity of LNG in cultured peripheral blood mononuclear cells (PBMC).

MATERIAL AND METHODS

After exposure to different doses (from 0.5 to 500 mg/L) of LNG, cell viability was measured by the MTT (3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and lactate dehydrogenase (LDH) leakage tests. The antioxidant activity was assessed by the total antioxidant capacity (TAC) and total oxidative stress (TOS) assays. To evaluate the genotoxic damage potential, chromosomal aberration (CA) frequencies and 8-oxo-2'-deoxyguanosine (8-oxo-dG) levels were determined.

RESULTS

Treatment with LNG did not cause statistically significant decreases of cell viability at lower concentrations than 100 mg/L as compared to untreated cultures. However, LNG exhibited cytotoxic action at 250 and 500 mg/L. Also, IC20 and IC50 values of LNG were determined as 8.827 and 70.307 mg/L, respectively. In addition, the oxidative analysis revealed that LNG supported antioxidant capacity at concentrations of 2.5, 5, 10, 25, 50 and 100 mg/L without generating oxidative stress. Besides, the results of CA and 8-oxo-dG assays showed in vitro non-genotoxic feature of LNG. As a conclusion, our findings clearly revealed that LNG had no cytotoxic and genotoxic actions, but exhibited antioxidative activity. In conclusion, therefore it is suggested that LNG use in diabetic patients is safe and provides protection against diabetic vascular and oxidative complications.

Insights Into GLP-1 and GIP Actions Emerging From Vildagliptin Mechanism Studies in Man

Vildagliptin blocks glucagon like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) inactivation of the meal induced increases in GLP-1 and GIP so that elevated GLP-1 and GIP levels are maintained over 24 h. The primary insulin secretion effect of vildagliptin is to improve the impaired sensitivity of the β-cells to glucose in subjects with impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) and in patients with type 2 diabetes mellitus (T2DM); this effect was seen acutely and maintained over at least 2 years in patients with T2DM. Vildagliptin was also associated with improved β-cell function that is likely secondary to the improved metabolic state. Although there was no evidence of restoration of β-cell mass, the preponderance of the vildagliptin data does indicate that for at least 2 years β-cell function was maintained in vildagliptin treated patients but not in the untreated patients. Vildagliptin suppressed an inappropriate glucagon response to an oral glucose challenge in patients with T2DM, to a mixed meal challenge in patients with T2DM and type 1 diabetes mellitus, and to a mixed meal challenge in subjects with IGT and IFG. The improved glucagon response was maintained for at least 2 years in patients with T2DM and there was no change in the glucagon response in normoglycemic individuals. Vildagliptin lowered glucose levels into the normal range without increasing hypoglycemia. These hypoglycemic benefits appear to be secondary in large part to the improved sensitivity of both the β and α-cell to glucose. In the case of the α-cell, if glucose levels are high, GLP-1 attenuates the glucagon levels and if glucose levels are low, GIP increases glucagon levels. Vildagliptin reduces fatty acid flux from the adipocyte leading to reduced liver fat which in turn leads to increased glucose utilization. The reduced glycosuria and reduced lipo-toxicity associated with vildagliptin therapy does not lead to weight gain presumably due to increased fat mobilization and oxidation during meals and to reduced fat extraction from the gut.