Bridging the gap between GLP1-receptor agonists and cardiovascular outcomes: evidence for the role of tirzepatide.

Tirzepatide is a new drug targeting glucagon-like peptide 1(GLP1) and gastric inhibitory polypeptide (GIP) receptors. This drug has demonstrated great potential in improving the clinical outcomes of patients with type 2 diabetes. It can lead to weight loss, better glycemic control, and reduced cardiometabolic risk factors. GLP1 receptor agonists have been proven effective antidiabetic medications with possible cardiovascular benefits. Even though they have been proven to reduce the risk of major adverse cardiovascular events, their effectiveness in treating heart failure is unknown. Unlike traditional GLP1 receptor agonists, tirzepatide is more selective for the GIP receptor, resulting in a more balanced activation of these receptors. This review article discusses the possible mechanisms tirzepatide may use to improve cardiovascular health. That includes the anti-inflammatory effect, the ability to reduce cell death and promote autophagy, and also its indirect effects through blood pressure, obesity, and glucose/lipid metabolism. Additionally, tirzepatide may benefit atherosclerosis and lower the risk of major adverse cardiac events. Currently, clinical trials are underway to evaluate the safety and efficacy of tirzepatide in patients with heart failure. Overall, tirzepatide's dual agonism of GLP1 and GIP receptors appears to provide encouraging cardiovascular benefits beyond glycemic control, offering a potential new therapeutic option for treating cardiovascular diseases and heart failure.

Tirzepatide against obesity and insulin-resistance: pathophysiological aspects and clinical evidence.

Obesity is a chronic, multifactorial disease in which accumulated excess body fat has a negative impact on health. Obesity continues to rise among the general population, resulting in an epidemic that shows no significant signs of decline. It is directly involved in development of cardiometabolic diseases, ischemic coronary heart disease peripheral arterial disease, heart failure, and arterial hypertension, producing global morbidity and mortality. Mainly, abdominal obesity represents a crucial factor for cardiovascular illness and also the most frequent component of metabolic syndrome. Recent evidence showed that Tirzepatide (TZP), a new drug including both Glucagon Like Peptide 1 (GLP-1) and Glucose-dependent Insulinotropic Polypeptide (GIP) receptor agonism, is effective in subjects with type 2 diabetes (T2D), lowering body weight, fat mass and glycated hemoglobin (HbA1c) also in obese or overweight adults without T2D. This review discusses the pathophysiological mechanisms and clinical aspects of TZP in treating obesity.

Tirzepatide modulates the regulation of adipocyte nutrient metabolism through long-acting activation of the GIP receptor.

Tirzepatide, a glucose-dependent insulinotropic polypeptide/glucagon-like peptide 1 receptor (GIPR/GLP-1R) agonist, has, in clinical trials, demonstrated greater reductions in glucose, body weight, and triglyceride levels compared with selective GLP-1R agonists in people with type 2 diabetes (T2D). However, cellular mechanisms by which GIPR agonism may contribute to these improved efficacy outcomes have not been fully defined. Using human adipocyte and mouse models, we investigated how long-acting GIPR agonists regulate fasted and fed adipocyte functions. In functional assays, GIPR agonism enhanced insulin signaling, augmented glucose uptake, and increased the conversion of glucose to glycerol in a cooperative manner with insulin; however, in the absence of insulin, GIPR agonists increased lipolysis. In diet-induced obese mice treated with a long-acting GIPR agonist, circulating triglyceride levels were reduced during oral lipid challenge, and lipoprotein-derived fatty acid uptake into adipose tissue was increased. Our findings support a model for long-acting GIPR agonists to modulate both fasted and fed adipose tissue function differentially by cooperating with insulin to augment glucose and lipid clearance in the fed state while enhancing lipid release when insulin levels are reduced in the fasted state.

Does glucose-dependent insulinotropic polypeptide receptor blockade as well as agonism have a role to play in management of obesity and diabetes?

Recent approval of the dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist, tirzepatide, for the management of type 2 diabetes mellitus (T2DM) has reinvigorated interest in exploitation of GIP receptor (GIPR) pathways as a means of metabolic disease management. However, debate has long surrounded the use of the GIPR as a therapeutic target and whether agonism or antagonism is of most benefit in management of obesity/diabetes. This controversy appears to be partly resolved by the success of tirzepatide. However, emerging studies indicate that prolonged GIPR agonism may desensitise the GIPR to essentially induce receptor antagonism, with this phenomenon suggested to be more pronounced in the human than rodent setting. Thus, deliberation continues to rage in relation to benefits of GIPR agonism vs antagonism. That said, as with GIPR agonism, it is clear that the metabolic advantages of sustained GIPR antagonism in obesity and obesity-driven forms of diabetes can be enhanced by concurrent GLP-1 receptor (GLP-1R) activation. This narrative review discusses various approaches of pharmacological GIPR antagonism including small molecule, peptide, monoclonal antibody and peptide-antibody conjugates, indicating stage of development and significance to the field. Taken together, there is little doubt that interesting times lie ahead for GIPR agonism and antagonism, either alone or when combined with GLP-1R agonists, as a therapeutic intervention for the management of obesity and associated metabolic disease.

Ameliorative effect of lixisenatide on diabetic cardiovascular damage and its enhancement via ticagrelor co-administration in rats: possible role of eNOS and NrF2 /HO-1 signaling.

In this study, we hypothesized that lixisenatide (LIX) and ticagrelor (TIC) could have a protective effect against type 2 diabetes mellitus (T2DM)-induced vascular damage. Furthermore, we explored the possible additional protective effect of co-administering LIX and TIC in the treatment regimen. Methods: 50 male rats were divided into five groups, each comprising 10 rats: C (control), D (T2DM rats), D + LIX (T2DM rats treated with LIX for 4 weeks), D + TIC (T2DM rats treated with TIC for 4 weeks), and D + LIX + TIC (T2DM rats treated with LIX + TIC for 4 weeks). Results: The D group showed an increase in body weight, blood glucose, hemostatic model assessment for insulin resistance (HOMA-IR), aorta reactive oxygen species (ROS), and nuclear factor kappa B (NF-κ B), along with a reduction in serum insulin, aorta superoxide dismutase (SOD), glutathione reduced (GSH), nuclear factor erythroid-2 (NrF2), hemeoxygenase-1 (HO-1), and endothelial nitric oxide synthase (eNOS). Deterioration in the aorta histopathological condition, coupled with a noticeable impairment in vascular reactivity compared to the C group, was observed. A single administration of LIX showed a reduction in body weight, blood glucose, HOMA-IR, aorta ROS, and NF-κ B, accompanied by an increase in serum insulin, aorta SOD, GSH, NrF2, HO-1, and eNOS. Amelioration in the aorta histopathological condition and improved vascular reactivity compared to the D group were reported. Similarly, a single administration of TIC showed a reduction in aorta ROS and NF-κ B, along with an increase in aorta SOD, GSH, NrF2, HO-1, and eNOS. A slight amelioration was detected in the aorta histopathological condition, with improved vascular reactivity compared to the D group. The combined administration of LIX and TIC showed a reduction in aorta ROS and NF-κ B, along with an increase in aorta GSH, SOD, HO-1, and eNOS. This was combined with evident amelioration in the aorta histopathological condition and noticeable improvement in vascular reactivity compared to the single treatment with either LIX or TIC group. Conclusion: The present study introduces clear evidence that the administration of LIX and TIC can improve metabolic and vascular complications of T2DM through modulating eNOS and NrF2 /HO-1 signaling. The combined administration of LIX and TIC produced more significant effects than a single treatment.

Real world use of tirzepatide in the treatment of type 2 diabetes in an Arab population.

AIM: Tirzepatide is a glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 (GLP-1) dual receptor agonist (RA) that reduces glycated haemoglobin (HbA1c) and weight in patients with type 2 diabetes. We assessed the effectiveness of tirzepatide in real-world use in an Arab population. METHODS: Review of clinical data from a specialist outpatient diabetes centre; study time points and outcome measures were pre-specified. RESULTS: Tirzepatide was initiated in 8945 patients between 24 October 2022 and 31 December 2023. Of these, 3686 individuals reached 40 weeks of follow-up. At initiation, the mean ± SD age was 54.1 ± 11.5 years, body mass index 34.6 ± 6.0 kg/m2 and HbA1c 7.3 ± 1.5% (56 ± 17 mmol/mol); 2296 (62%) were switched to tirzepatide from another GLP-RA and 317 (8.6%) reported previous bariatric surgery. The maximum dose dispensed was ≥12.5 mg/week in 1087, 7.5-10.0 mg/week in 1688 and 2.5-5.0 mg/week in 911. The mean 40-week reduction in HbA1c was 0.6 ± 1.2% (8 ± 13 mmol/mol) and the reduction in weight was 4.5 ± 6.9 kg (4.8 ± 7.3%). GLP-RA-naïve patients experienced a significantly greater reduction in HbA1c [1.0 ± 1.3% (11 ± 14 mmol/mol) versus 0.5 ± 1.2% (6 ± 13 mmol/mol), p < .0001] and weight (7.2 ± 8.6 vs. 4.2 ± 6.6 kg, p < .0001) compared with previously exposed individuals. Post-metabolic bariatric surgery patients lost significantly more weight (7.8 ± 9.4 vs. 4.5 ± 7.0 kg, p < .0001). Improvements in blood pressure, lipid profile, and liver transaminases were noted at 40 weeks. Tirzepatide was well tolerated, with 288 (7.8%) of patients discontinuing treatment because of adverse effects, predominantly gastrointestinal. CONCLUSION: In real-world use, tirzepatide significantly reduced HbA1c levels and weight and was well tolerated. Previous GLP-RA use was associated with significantly lesser HbA1c and weight reduction, and previous metabolic bariatric surgery was associated with greater weight loss.

Cost-utility analysis and drug pricing for tirzepatide for type 2 diabetes in the Chinese market compared with semaglutide.

AIM: To investigate the most matchable price of tirzepatide (TIRZ) compared with semaglutide (SEMA) in the treatment of type 2 diabetes in China. METHODS: The patient cohort and clinical efficacy data were derived from the SURPASS-2 trial. Cost-utility analysis and a binary search were performed to identify the most matchable price of TIRZ from a Chinese healthcare provider's perspective. RESULTS: After lifetime simulation, the quality-adjusted life years of TIRZ 5, 10, 15 mg and SEMA 1 mg were 11.17, 11.21, 11.27 and 11.12 years, respectively. Despite an initial assumption that the annual cost of TIRZ equals that of SEMA, our analysis revealed that TIRZ is probably more cost-effective than SEMA. A thorough evaluation of pricing showed that the cost ranges for TIRZ at doses of 5, 10 and 15 mg were $1628.61-$1846.23, $1738.40-$2140.95 and $1800.30-$2430.81, respectively. After adjustment in the univariate sensitivity analysis, the cost ranges for TIRZ 5, 10 and 15 mg were $1542.68-$1757.57, $1573.00-$1967.16 and $1576.54-$2133.96, respectively. These cost intervals were validated through robust probabilistic sensitivity analysis and scenario analysis, except for the cost range for TIRZ 5 mg. CONCLUSIONS: This study shows that, using SEMA as a reference, the annual costs for TIRZ 10 and 15 mg are $1573.00-$1967.16 and $1576.54-$2133.96, respectively, for patients with type 2 diabetes in China.

Tirzepatide 5, 10 and 15 mg versus injectable semaglutide 0.5 mg for the treatment of type 2 diabetes: An adjusted indirect treatment comparison.

AIMS: To compare the efficacy and safety of tirzepatide 5, 10 and 15 mg with subcutaneous semaglutide 0.5 mg as second-line treatment for adults with type 2 diabetes mellitus, after metformin monotherapy, using adjusted indirect treatment comparisons (aITCs). METHODS: The aITCs were performed using the Bucher method to compare the relative efficacy and safety of tirzepatide 5, 10 and 15 mg versus semaglutide 0.5 mg via a common comparator (subcutaneous semaglutide 1.0 mg) based on trial results from SURPASS-2 (NCT03987919) and SUSTAIN7 (NCT02648204). RESULTS: All tirzepatide doses showed statistically significantly greater reductions in glycated haemoglobin, body weight and body mass index from baseline to week 40, with a comparable adverse event (AE) profile and no statistically significant differences in the odds of gastrointestinal AEs versus semaglutide 0.5 mg. Furthermore, all tirzepatide doses showed greater odds of patients achieving HbA1c targets of ≤ 6.5 % (≤48 mmol/mol) and < 7.0 % (<53 mmol/mol) and weight loss targets of ≥ 5 % and ≥ 10 %, versus semaglutide 0.5 mg. CONCLUSIONS: In these aITCs, glycated haemoglobin and weight reductions were significantly greater for all tirzepatide doses versus semaglutide 0.5 mg with a comparable AE profile. These findings provide comparative effectiveness insights in the absence of a head-to-head clinical trial.

Characterization of tirzepatide-treated patients achieving different glycemic control levels in SURPASS-AP-Combo.

OBJECTIVE: The study objective was to characterize subgroups of Asia-Pacific patients with type 2 diabetes who achieved different glycated hemoglobin (HbA1c) targets on tirzepatide treatment. METHODS: This was a post hoc analysis of the SURPASS AP-Combo study. Baseline characteristics, changes in metabolic markers, and safety were compared between tirzepatide-treated patients achieving HbA1c <7.0% (<53 mmol/mol) and those achieving ≥7.0% (≥53 mmol/mol) at week 40. Among patients achieving HbA1c <7.0% (<53 mmol/mol), further comparisons were conducted among subgroups achieving HbA1c <5.7% (<39 mmol/mol), 5.7% to 6.5% (39 to 48 mmol/mol), and >6.5% to <7.0% (>48 to <53 mmol/mol). RESULTS: Five hundred ninety-eight patients on tirzepatide treatment without rescue medication were included (56.9% male; mean age: 53.1 years; mean baseline HbA1c: 8.7% [71.6 mmol/mol]). Patients achieving HbA1c <7.0% (<53 mmol/mol) versus ≥7.0% (≥53 mmol/mol) were slightly younger with a shorter disease duration and lower HbA1c at baseline, and they had greater improvements in HbA1c, fasting serum glucose, body weight, BMI, waist circumference, waist-height ratio, diastolic blood pressure, lipids, and self-monitored blood glucose at week 40. Patients achieving HbA1c <5.7% (<39 mmol/mol) versus those achieving 5.7% to 6.5% (39 to 48 mmol/mol) and those achieving >6.5% to <7.0% (>48 to <53 mmol/mol) were much younger, had much lower HbA1c, and had further improvements in metabolic markers. Tirzepatide treatment was well tolerated irrespective of the HbA1c level achieved, with a low incidence of hypoglycemic events. CONCLUSIONS: These findings may help to inform clinical decisions in Asia-Pacific patients with type 2 diabetes.

Lixisenatide in early parkinson's disease: efficacy, safety, and future directions: a correspondence.

Parkinson's disease (PD) presents as a complex neurodegenerative disorder characterized by motor and non-motor symptoms, resulting from dopaminergic neuron degeneration. Current treatment strategies primarily aim to alleviate symptoms through pharmacotherapy and supportive therapies. However, emerging research explores novel therapeutic avenues, including the repurposing of drugs like lixisenatide, a GLP-1 receptor agonist initially developed for type 2 diabetes. This correspondence summarizes a phase 2 clinical trial investigating lixisenatide's efficacy in early PD, demonstrating a potential for mitigating motor disability progression. Findings reveal a marginal improvement or stabilization in motor function among lixisenatide-treated individuals compared to placebo, emphasizing its therapeutic promise. Nonetheless, the emergence of gastrointestinal adverse events underscores the need for careful monitoring and management. Further extensive trials are warranted to delineate lixisenatide's efficacy and safety profile, fostering collaborative efforts towards precision treatments in PD.

Targeting the GLP-2 receptor in the management of obesity.

Recent advancements in understanding glucagon-like peptide 2 (GLP-2) biology and pharmacology have sparked interest in targeting the GLP-2 receptor (GLP-2R) in the treatment of obesity. GLP-2 is a proglucagon-derived 33-amino acid peptide co-secreted from enteroendocrine L cells along with glucagon-like peptide 1 (GLP-1) and has a range of actions via the GLP-2R, which is particularly expressed in the gastrointestinal tract, the liver, adipose tissue, and the central nervous system (CNS). In humans, GLP-2 evidently induces intestinotrophic effects (i.e., induction of intestinal mucosal proliferation and improved gut barrier function) and promotes mesenteric blood flow. However, GLP-2 does not seem to have appetite or food intake-reducing effects in humans, but its gut barrier-promoting effect may be of interest in the context of obesity. Obesity is associated with reduced gut barrier function, increasing the translocation of proinflammatory gut content to the circulation. This phenomenon constitutes a strong driver of obesity-associated systemic low-grade inflammation, which in turn plays a major role in the development of most obesity-associated complications. Thus, the intestinotrophic and gut barrier-improving effect of GLP-2, which in obese rodent models shows strong anti-inflammatory potential, may, in combination with food intake-reducing strategies, e.g., GLP-1 receptor (GLP-1) agonism, be able to rectify core pathophysiological mechanism of obesity. Here, we provide an overview of GLP-2 physiology in the context of obesity pathophysiology and review the pharmacological potential of GLP-2R activation in the management of obesity and related comorbidities.

Early-Onset Type 2 Diabetes and Tirzepatide Treatment: A Post Hoc Analysis From the SURPASS Clinical Trial Program.

OBJECTIVE: We evaluated baseline characteristics of participants with early-onset type 2 diabetes (T2D) from the SURPASS program and tirzepatide's effects on glycemic control, body weight (BW), and cardiometabolic markers. RESEARCH DESIGN AND METHODS: This post hoc analysis compared baseline characteristics and changes in mean HbA1c, BW, waist circumference (WC), lipids, and blood pressure (BP) in 3,792 participants with early-onset versus later-onset T2D at week 40 (A Study of Tirzepatide [LY3298176] in Participants With Type 2 Diabetes Not Controlled With Diet and Exercise Alone [SURPASS-1] and A Study of Tirzepatide [LY3298176] Versus Semaglutide Once Weekly as Add-on Therapy to Metformin in Participants With Type 2 Diabetes [SURPASS-2]) or week 52 (A Study of Tirzepatide [LY3298176] Versus Insulin Degludec in Participants With Type 2 Diabetes [SURPASS-3]). Analyses were performed by study on data from participants while on assigned treatment without rescue medication in case of persistent hyperglycemia. RESULTS: At baseline in SURPASS-2, participants with early-onset versus later-onset T2D were younger with longer diabetes duration (9 vs. 7 years, P < 0.001) higher glycemic levels (8.5% vs. 8.2%, P < 0.001), higher BW (97 vs. 93 kg, P < 0.001) and BMI (35 vs. 34 kg/m2, P < 0.001), and a similarly abnormal lipid profile (e.g., triglycerides 167 vs. 156 mg/dL). At week 40, similar improvements in HbA1c (-2.6% vs. -2.4%), BW (-14 vs. -13 kg), WC (-10 vs. -10 cm), triglycerides (-26% vs. -24%), HDL (7% vs. 7%), and systolic BP (-6 vs. -7 mmHg) were observed in both subgroups with tirzepatide. CONCLUSIONS: Despite younger age, participants with early-onset T2D from the SURPASS program had higher glycemic levels and worse overall metabolic health at baseline versus those with later-onset T2D. In this post hoc analysis, similar improvements in HbA1c, BW, and cardiometabolic markers were observed with tirzepatide, irrespective of age at T2D diagnosis. Future studies are needed to determine long-term outcomes of tirzepatide in early-onset T2D.

Real-world effectiveness and safety of insulin glargine 100 U/mL plus lixisenatide in adults with type 2 diabetes: An international, multicentre, 12-month, prospective observational study.

AIM: To assess the impact of insulin glargine (100 U/mL) and lixisenatide (iGlarLixi) fixed-ratio combination therapy on the overall management of glycaemia in patients with type 2 diabetes (T2D), previously inadequately controlled with oral antidiabetic drugs ± basal insulin or glucagon-like peptide-1 receptor agonists (GLP-1 RAs). MATERIALS AND METHODS: This 12-month, international, multicentre, prospective, observational study included patients (age ≥ 18 years) with T2D who had initiated iGlarLixi within 1 month prior to study inclusion. Data were collected at study inclusion, month 3, month 6 and month 12 from patient diaries, self-measured plasma glucose, and questionnaires. The primary endpoint was change in HbA1c from baseline to month 6. RESULTS: Of the 737 eligible participants (mean age: 57.8 [standard deviation: 11.2] years; male: 49%), 685 had baseline and post-baseline HbA1c data available. The least squares mean change in HbA1c from baseline to month 6 was -1.4% (standard error [95% confidence interval (CI)]: 0.05 [-1.5, -1.3]). The absolute change from baseline at month 12 was -1.7% ± 1.9% (95% CI: -1.9, -1.5). There were 72 hypoglycaemia events reported during the study period, with a very low incidence of severe hypoglycaemia (two participants [rate: 0.003 events per patient-year]). CONCLUSIONS: This real-world observational study shows that initiation of iGlarLixi in people with T2D inadequately controlled on oral antidiabetic drugs ± basal insulin or GLP-1 RAs improves glycaemic control with a low incidence of hypoglycaemia.

Subcutaneously administered tirzepatide vs semaglutide for adults with type 2 diabetes: a systematic review and network meta-analysis of randomised controlled trials.

AIMS/HYPOTHESIS: We conducted a systematic review and network meta-analysis to compare the efficacy and safety of s.c. administered tirzepatide vs s.c. administered semaglutide for adults of both sexes with type 2 diabetes mellitus. METHODS: We searched PubMed and Cochrane up to 11 November 2023 for RCTs with an intervention duration of at least 12 weeks assessing s.c. tirzepatide at maintenance doses of 5 mg, 10 mg or 15 mg once weekly, or s.c. semaglutide at maintenance doses of 0.5 mg, 1.0 mg or 2.0 mg once weekly, in adults with type 2 diabetes, regardless of background glucose-lowering treatment. Eligible trials compared any of the specified doses of tirzepatide and semaglutide against each other, placebo or other glucose-lowering drugs. Primary outcomes were changes in HbA1c and body weight from baseline. Secondary outcomes were achievement of HbA1c target of ≤48 mmol/mol (≤6.5%) or <53 mmol/mol (<7.0%), body weight loss of at least 10%, and safety outcomes including gastrointestinal adverse events and severe hypoglycaemia. We used version 2 of the Cochrane risk-of-bias tool (ROB 2) to assess the risk of bias, conducted frequentist random-effects network meta-analyses and evaluated confidence in effect estimates utilising the Confidence In Network Meta-Analysis (CINeMA) framework. RESULTS: A total of 28 trials with 23,622 participants (44.2% female) were included. Compared with placebo, tirzepatide 15 mg was the most efficacious treatment in reducing HbA1c (mean difference -21.61 mmol/mol [-1.96%]) followed by tirzepatide 10 mg (-20.19 mmol/mol [-1.84%]), semaglutide 2.0 mg (-17.74 mmol/mol [-1.59%]), tirzepatide 5 mg (-17.60 mmol/mol [-1.60%]), semaglutide 1.0 mg (-15.25 mmol/mol [-1.39%]) and semaglutide 0.5 mg (-12.00 mmol/mol [-1.09%]). In between-drug comparisons, all tirzepatide doses were comparable with semaglutide 2.0 mg and superior to semaglutide 1.0 mg and 0.5 mg. Compared with placebo, tirzepatide was more efficacious than semaglutide for reducing body weight, with reductions ranging from 9.57 kg (tirzepatide 15 mg) to 5.27 kg (tirzepatide 5 mg). Semaglutide had a less pronounced effect, with reductions ranging from 4.97 kg (semaglutide 2.0 mg) to 2.52 kg (semaglutide 0.5 mg). In between-drug comparisons, tirzepatide 15 mg, 10 mg and 5 mg demonstrated greater efficacy than semaglutide 2.0 mg, 1.0 mg and 0.5 mg, respectively. Both drugs increased incidence of gastrointestinal adverse events compared with placebo, while neither tirzepatide nor semaglutide increased the risk of serious adverse events or severe hypoglycaemia. CONCLUSIONS/INTERPRETATION: Our data show that s.c. tirzepatide had a more pronounced effect on HbA1c and weight reduction compared with s.c. semaglutide in people with type 2 diabetes. Both drugs, particularly higher doses of tirzepatide, increased gastrointestinal adverse events. REGISTRATION: PROSPERO registration no. CRD42022382594.

Glucagon-like peptide-1 class drugs show clear protective effects in Parkinson's and Alzheimer's disease clinical trials: A revolution in the making?

Parkinson's disease (PD) is a complex syndrome for which there is no disease-modifying treatment on the market. However, a group of drugs from the Glucagon-like peptide-1 (GLP-1) class have shown impressive improvements in clinical phase II trials. Exendin-4 (Bydureon), Liraglutide (Victoza, Saxenda) and Lixisenatide (Adlyxin), drugs that are on the market as treatments for diabetes, have shown clear effects in improving motor activity in patients with PD in phase II clinical trials. In addition, Liraglutide has shown improvement in cognition and brain shrinkage in a phase II trial in patients with Alzheimer disease (AD). Two phase III trials testing the GLP-1 drug semaglutide (Wegovy, Ozempic, Rybelsus) are ongoing. This perspective article will summarize the clinical results obtained so far in this novel research area. We are at a crossroads where GLP-1 class drugs are emerging as a new treatment strategy for PD and for AD. Newer drugs that have been designed to enter the brain easier are being developed already show improved effects in preclinical studies compared with the older GLP-1 class drugs that had been developed to treat diabetes. The future looks bright for new treatments for AD and PD.

The preclinical discovery and clinical evaluation of tirzepatide for the treatment of type 2 diabetes.

INTRODUCTION: Despite numerous antidiabetic medications available for the treatment of type 2 diabetes, a substantial percentage of patients fail to achieve optimal glycemic control. Furthermore, the escalating obesity pandemic underscores the urgent need for effective relevant pharmacotherapies. Tirzepatide, a novel dual GIP and GLP-1 receptor agonist, offers a promising therapeutic option. AREAS COVERED: This review describes the discovery and clinical development of tirzepatide. Based on data from pivotal in vivo and in vitro studies, the authors present the pharmacodynamic profile of tirzepatide. Furthermore, they summarize data from the clinical trial programs that assessed the efficacy and safety of tirzepatide for the treatment of type 2 diabetes or obesity in a broad spectrum of patients, and discuss its therapeutic potential. EXPERT OPINION: Tirzepatide effectively reduces glucose levels and body weight in patients with type 2 diabetes and/or obesity, with a generally safe profile. Based on data from phase 3 clinical trials, several agencies have approved its use for the treatment of type 2 diabetes and obesity. Clinicians should be aware of possible adverse events, mainly mild-to-moderate gastrointestinal side effects. Overall, tirzepatide represents a promising treatment option for the treatment of type 2 diabetes.

Renal effects of GLP-1 receptor agonists and tirzepatide in individuals with type 2 diabetes: seeds of a promising future.

PURPOSE: Chronic kidney disease (CKD) is one of the most common complications of type 2 diabetes (T2D), and CKD-related disability and mortality are increasing despite the recent advances in diabetes management. The dual GIP/GLP-1 receptor agonist tirzepatide is among the furthest developed multi-agonists for diabetes care and has so far displayed promising nephroprotective effects. This review aims to summarize the evidence regarding the nephroprotective effects of glucagon-like peptide-1 receptor agonists (GLP-1RA) and tirzepatide and the putative mechanisms underlying the favorable renal profile of tirzepatide. METHODS: A comprehensive literature search was performed from inception to July 31st 2023 to select research papers addressing the renal effects of GLP-1RA and tirzepatide. RESULTS: The pathogenesis of CKD in patients with T2D likely involves many contributors besides hyperglycemia, such as hypertension, obesity, insulin resistance and glomerular atherosclerosis, exerting kidney damage through metabolic, fibrotic, inflammatory, and hemodynamic mechanisms. Tirzepatide displayed an unprecedented glucose and body weight lowering potential, presenting also with the ability to increase insulin sensitivity, reduce systolic blood pressure and inflammation and ameliorate dyslipidemia, particularly by reducing triglycerides levels. CONCLUSION: Tirzepatide is likely to counteract most of the pathogenetic factors contributing to CKD in T2D, potentially representing a step forward in incretin-based therapy towards nephroprotection. Further evidence is needed to understand its role in renal hemodynamics, fibrosis, cell damage and atherosclerosis, as well as to conclusively show reduction of hard renal outcomes.

Efficacy and Safety of Tirzepatide in Overweight and Obese Adult Patients with Type 1 Diabetes.

Introduction and Objective: Most patients with type 1 diabetes (T1D) in the United States are overweight (OW) or obese (OB), contributing to insulin resistance and suboptimal glucose control. The primary Food and Drug Administration-approved treatment for T1D is insulin, which may adversely affect weight. Tirzepatide is approved for managing type 2 diabetes, improves glucose control, facilitates weight loss, and improves cardiovascular disease outcomes. We assessed the use of tirzepatide in OW/OB subjects with T1D. Methods: This was a retrospective single-center real-world study in 62 OW/OB adult patients with T1D who were prescribed tirzepatide (treated group) and followed for 1 year. At least 3 months of use of tirzepatide was one of the inclusion criteria. Based on the inclusion criteria, this study represents 62 patients out of 184 prescribed tirzepatide. The control group included 37 OW/OB patients with T1D (computer frequency matched by age, duration of diabetes, gender, body mass index (BMI), and glucose control) who were not using any other weight-loss medications during the same period. The mean (±standard deviation [SD]) dose of weekly tirzepatide at 3 months was 5.6 ± 1.9 mg that increased to 9.7 ± 3.3 mg at 1 year. Results: The gender, mean baseline age, duration of diabetes, and glycosylated hemoglobin (HbA1c) were similar in the two groups, whereas BMI and weight were higher in the treated group. There were significantly larger declines in BMI and weight in the treated group than in controls across all time points among those in whom data were available. HbA1c decreased in the treated group as early as 3 months and was sustained through a 1-year follow-up (-0.67% at 1 year). As expected, insulin dose decreased at 3 months and throughout the study period. There were no reported hospitalizations from severe hypoglycemia or diabetic ketoacidosis. The mean glucose, time-in-range, time-above-range, SD, and coefficient of variation (continuous glucose monitoring metrics) significantly improved in the treated group. Conclusions: In this pilot (off label) study, we conclude that tirzepatide facilitated an average 18.5% weight loss (>46 pounds) and improved glucose control in OW/OB patients with T1D at 1 year. For safe use of tirzepatide in patients with T1D, we strongly recommend a large prospective randomized control trial in OW/OB patients with T1D.

Effect of tirzepatide on body fat distribution pattern in people with type 2 diabetes.

AIMS: To describe the overall fat distribution patterns independent of body mass index (BMI) in participants with type 2 diabetes (T2D) in the SURPASS-3 MRI substudy by comparison with sex- and BMI-matched virtual control groups (VCGs) derived from the UK Biobank imaging study at baseline and Week 52. METHODS: For each study participant at baseline and Week 52 (N = 296), a VCG of ≥150 participants with the same sex and similar BMI was identified from the UK Biobank imaging study (N = 40 172). Average visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (aSAT) and liver fat (LF) levels and the observed standard deviations (SDs; standardized normal z-scores: z-VAT, z-aSAT and z-LF) were calculated based on the matched VCGs. Differences in z-scores between baseline and Week 52 were calculated to describe potential shifts in fat distribution pattern independent of weight change. RESULTS: Baseline fat distribution patterns were similar across pooled tirzepatide (5, 10 and 15 mg) and insulin degludec (IDeg) arms. Compared with matched VCGs, SURPASS-3 participants had higher baseline VAT (mean [SD] z-VAT +0.42 [1.23]; p < 0.001) and LF (z-LF +1.24 [0.92]; p < 0.001) but similar aSAT (z-aSAT -0.13 [1.11]; p = 0.083). Tirzepatide-treated participants had significant decreases in z-VAT (-0.18 [0.58]; p < 0.001) and z-LF (-0.54 [0.84]; p < 0.001) but increased z-aSAT (+0.11 [0.50]; p = 0.012). Participants treated with IDeg had a significant change in z-LF only (-0.46 [0.90]; p = 0.001), while no significant changes were observed for z-VAT (+0.13 [0.52]; p = 0.096) and z-aSAT (+0.09 [0.61]; p = 0.303). CONCLUSION: In this exploratory analysis, treatment with tirzepatide in people with T2D resulted in a significant reduction of z-VAT and z-LF, while z-aSAT was increased from an initially negative value, suggesting a possible treatment-related shift towards a more balanced fat distribution pattern with prominent VAT and LF loss.