Looking ahead to potential incretin combination therapies for non-alcoholic steatohepatitis in patients with diabetes

INTRODUCTION

There are no drugs approved by regulatory agencies for the treatment of nonalcoholic fatty liver disease (NAFLD); incretin combination therapies are being developed for treatment of type 2 diabetes and research has moved to test their usefulness in NAFLD.

AREAS COVERED

We reviewed the literature on the effectiveness of dual and triple peptides combining receptor agonists of the glucagon-like peptide 1, the glucose-dependent insulinotropic peptide, and glucagon to treat NAFLD and its associated metabolic diseases, and/or the cardiovascular risk intimately connected with the cluster of the metabolic syndrome. Other combination peptides involved the glucagon-like peptide 2 receptor, the fibroblast growth factor 21, the cholecystokinin receptor 2, and the amylin receptor.

EXPERT OPINION

Both dual and triple agonists are promising, based on animal, pharmacokinetic and proof-of concept studies, showing effectiveness both in the presence and the absence of diabetes on a few validated surrogate NAFLD biomarkers, but the majority of studies are still in progress. Considering the long natural history of NAFLD, final proof of their efficacy on primary clinical liver outcomes might be also derived from the analysis of large databases of National Healthcare Systems or Insurance companies, when used in diabetes for improving glycemic control, after careful propensity-score matching.

Is retatrutide (LY3437943), a GLP-1, GIP, and glucagon receptor agonist a step forward in the treatment of diabetes and obesity?

INTRODUCTION

Despite there being a wide range of medicines available for the treatment of type 2 diabetes, the high rate of mortality, suggests treatment needs to be improved. Only a few medicines have shown long-term effectiveness in obesity, and new medicines are urgently needed.

AREAS COVERED

A multiple-ascending dose phase 1b clinical trial of a new drug retatrutide (LY3437943), which in addition to stimulating Glucagon-like peptide 1 (GLP-1) and Glucose-dependent insulinotropic polypeptide (GIP) receptors, stimulates glucagon receptors, in subjects with type 2 diabetes. Retatrutide was relatively safe and pharmacokinetics support once-weekly dosing.

EXPERT OPINION

The role of stimulating glucagon receptors in the treatment of type 2 diabetes and/or obesity is poorly defined and needs to be clarified. Although retatrutide may be superior to the GLP-1 receptor agonist dulaglutide in reducing plasma glucose and body weight, this is not a meaningful comparison, as another GLP-1 receptor agonist (semaglutide) is more potent than dulaglutide at this and may have similar efficacy to retatrutide. Retatrutide also needs to be compared to another Eli Lilly and Company drug, the combined GLP-1 and GIP receptor agonist, tirzepatide. The safety of retatrutide needs to be determined in larger and longer trials.

Achievement of glycaemic targets with weight loss and without hypoglycaemia in type 2 diabetes with the once-weekly glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist tirzepatide: A post hoc analysis of the SURPASS-1 to -5 studies

AIM

To assess composite endpoints combining glycaemic control (HbA1c < 7.0%, ≤ 6.5% or < 5.7%) with weight loss (≥ 5%, ≥ 10% or ≥ 15%) and without hypoglycaemia with tirzepatide in type 2 diabetes (T2D).

MATERIALS AND METHODS

Data from the phase 3 SURPASS programme were evaluated post hoc by trial. Participants with T2D were randomized to tirzepatide (5, 10 and 15 mg), placebo (SURPASS-1,5), semaglutide 1 mg (SURPASS-2) or titrated basal insulin (SURPASS-3,4). The proportions of participants achieving the composite endpoints were compared between tirzepatide and the respective comparator groups at week 40/52.

RESULTS

The proportions of participants achieving an HbA1c value of less than 7.0% with 5% or more weight loss and without hypoglycaemia ranged from 43% to 82% with tirzepatide across the SURPASS-1 to -5 trials versus 4%-5% with placebo, 51% with semaglutide 1 mg and 5% with basal insulin (P < .001 vs. all comparators). The proportions of participants achieving an HbA1c value of less than 7.0% with 10% or more, or 15% or more weight loss and without hypoglycaemia were significantly higher with all tirzepatide doses versus comparators across trials (P < .001 or P < .05). Similar results were observed for all other combinations of endpoints with an HbA1c value of 6.5% or less, or less than 5.7%, with more tirzepatide-treated participants achieving these endpoints versus those in the comparator groups, including semaglutide.

CONCLUSIONS

Across the SURPASS-1 to -5 clinical trials, more tirzepatide-treated participants with T2D achieved clinically meaningful composite endpoints, which included reaching glycaemic targets with various degrees of weight loss and without hypoglycaemia, than those in the comparator groups.

Tirzepatide as Monotherapy Improved Markers of Beta-cell Function and Insulin Sensitivity in Type 2 Diabetes (SURPASS-1)

Context

Tirzepatide is a glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist approved for treatment of type 2 diabetes (T2D). SURPASS-1, a phase 3 trial of tirzepatide monotherapy in people with early T2D, enables evaluating effects of tirzepatide on pancreatic beta-cell function and insulin sensitivity (IS) without other background antihyperglycemic medications.

Objective

Explore changes in biomarkers of beta-cell function and IS with tirzepatide monotherapy.

Design

Post hoc analyses of fasting biomarkers with analysis of variance and mixed model repeated measures.

Setting

Forty-seven sites in 4 countries.

Patients

Four hundred seventy-eight T2D participants.

Intervention

Tirzepatide (5, 10, 15 mg), placebo.

Main Outcome Measures

Analyze biomarkers of beta-cell function and IS at 40 weeks.

Results

At 40 weeks, markers of beta-cell function improved with tirzepatide monotherapy vs placebo with reductions from baseline in fasting proinsulin levels (49-55% vs -0.6%) and in intact proinsulin/C-peptide ratios (47-49% vs -0.1%) (P < .001, all doses vs placebo). Increases from baseline in homeostatic model assessment for beta-cell function (computed with C-peptide) (77-92% vs -1.4%) and decreases in glucose-adjusted glucagon levels (37-44% vs +4.8%) were observed with tirzepatide vs placebo (P < .001, all doses vs placebo). IS improved as indicated by reductions from baseline in homeostatic model assessment for insulin resistance (9-23% vs +14.7%) and fasting insulin levels (2-12% vs +15%), and increases in total adiponectin (16-23% vs -0.2%) and insulin-like growth factor binding protein 2 (38-70% vs +4.1%) with tirzepatide vs placebo at 40 weeks (P ≤ .031, all doses vs placebo, except for fasting insulin levels with tirzepatide 10 mg).

Conclusions

As monotherapy for early T2D, tirzepatide achieved significant improvements in biomarkers of both pancreatic beta-cell function and IS.

Comparative effectiveness of glucagon-like peptide-1 receptor agonists for the management of obesity in adults without diabetes: A network meta-analysis of randomized clinical trials

Tirzepatide is a new glucagon-like peptide-1 receptor agonist (GLP-1RA) that has shown promising results for weight loss. A Bayesian network meta-analysis was conducted to compare the efficacy and safety of GLP-1RAs for obesity management. Embase and MEDLINE were searched looking for randomized clinical trials (RCTs) that evaluated the efficacy of GLP-1RAs for weight loss in patients without diabetes. The main efficacy outcomes evaluated were the mean change in actual and percentage weight loss and the proportion of patients with weight loss of ≥5%-20%. Main safety outcomes evaluated include nausea, vomiting, diarrhea, constipation, loss of appetite, pancreatitis, gallbladder-related disorders, and withdrawal due to adverse events. Seven RCTs with more than 12,300 patients were analyzed, including patients with body mass index (BMI) ≥ 30 kg/m² , or BMI ≥ 27 kg/m² with comorbidities. Weekly tirzepatide 10 and 15 mg resulted in more weight loss than weekly semaglutide 2.4 mg, daily semaglutide 0.4 mg, or liraglutide 3 mg. Tirzepatide and weekly semaglutide demonstrated comparable results but with significantly higher odds of achieving ≥5%-20% weight loss compared with liraglutide. GLP-1RAs triggered more gastrointestinal adverse events than placebo, with no in-between difference. Although all GLP-1RAs lead to significant weight reduction, tirzepatide was associated with better efficacy outcomes while having a comparable safety profile.

Human Epicardial Adipose Tissue Expresses Glucose-dependent Insulinotropic Polypeptide, Glucagon and Glucagon-Like Peptide 1 Receptors as Potential Targets of Pleiotropic Therapies

BACKGROUND

Human Epicardial Adipose Tissue (EAT) plays a crucial role in the development and progression of coronary artery disease, atrial fibrillation and heart failure. Microscopically, EAT is composed of adipocytes, nerve tissues, inflammatory, stromovascular and immune cells. EAT is a white adipose tissue, albeit it also has brown-fat like or beige fat features. No muscle fascia divides EAT and myocardium; this allows a direct interaction and cross talk between the epicardial fat and the myocardium. Thus, it might be a therapeutic target for pharmaceutical compounds acting on G-Protein-Coupled Receptors, such as those for Glucose-dependent Insulinotropic Polypeptide (GIP), Glucagon (GCG) and Glucagon-Like Peptide-1 (GLP-1), whose selective stimulation with innovative drugs has demonstrated beneficial cardiovascular effects. The precise mechanism of these novel drugs and their tissue and cellular target(s) need to be better understood.

AIM

We evaluate whether human EAT expresses GIP, GCG and GLP-1 receptors and whether their presence is related to EAT transcriptome. We also investigated protein expression and cell type localization specifically for GIPR and GCGR.

METHODS

EAT samples were collected from 33 patients affected by cardiovascular diseases undergoing open heart surgery (90.9% males, age 67.2±10.5 years mean ± SD). Microarray and immunohistochemistry analysis were performed.

RESULTS

Microarray analysis showed that GIPR and GCGR messenger Ribonucleic Acids (mRNAs) are expressed in EAT, beyond confirming the previously found GLP-1(3776±1377 arbitrary unit (A.U.), 17.77±14.91 A.U., and 3.41±2.27 A.U., respectively). The immunohistochemical analysis consistently indicates that GIPR and GCGR are expressed in EAT, mainly in macrophages, isolated and in crown-like structures. In contrast, only some mature adipocytes of different sizes showed cytoplasmic immunostaining, similar to endothelial cells and pericytes in the capillaries and pre-capillary vascular structures. Notably, EAT GIPR is statistically associated with the low expression of genes involved in Free Fatty Acid (FFA) oxidation and transport and those promoting FFA biosynthesis and adipogenesis (p<0.01). EAT GCGR, in turn, is related to genes involved in FFA transport, mitochondrial fatty acid oxidation, and white-to-brown adipocyte differentiation, in addition to genes involved in the reduction of fatty acid biosynthesis and adipogenesis (p<0.01).

CONCLUSIONS

Having reported the expression of the GLP-1 receptor previously, here, we showed that GIPR and GCGR similarly present at mRNA and protein levels in human EAT, particularly in macrophages and partially adipocytes, suggesting these G-protein-coupled receptors as pharmacological targets on the ongoing innovative drugs, which seem cardiometabolically healthy well beyond their effects on glucose and body weight..

[The "other" incretin - the therapeutic rediscovery of the glucose-dependent insulinotropic polypeptide]

Among the two incretins that strongly stimulate insulin secretion and are also involved in its physiological regulation in type 2 diabetes, glucagon-like peptide-1 (GLP1) has been the focus of interest for a long time, due to its retained - although reduced - secretagogue nature also in type 2 diabetes. Its receptor agonists were also included in the antidiabetic treatment toolkit. In the light of more recent studies, however, the "other" incretin, the glucose-dependent insulinotropic polypeptide (GIP) has also come into a different light. It turned out that by regulating glucagon and insulin production according to blood sugar levels, it acts as a bifunctional blood sugar stabilizing factor in type 2 diabetes as well. The article reviews new data on the physiology of GIP, its verifiable effects in type 2 diabetes and obesity, the so-called "twincretin" effect as well as the benefits of the double stimulation of the GIP and the GLP1 receptor. It describes the pharmacology of the first dual receptor agonist, tirzepatide, already incorporated in therapeutic recommendations, and the first clinical trials related to its use. In the light of the data so far, the molecule may open new horizons in the treatment of type 2 diabetes and obesity. Orv Hetil. 2023; 164(6): 210-218.

Adverse Events Related to Tirzepatide

Context

Tirzepatide is a dual glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide-1 receptor agonist (GLP-1 RA) approved by the US Food and Drug Administration in May 2022 for patients with type 2 diabetes mellitus (T2DM).

Objective

We aimed to determine the rates of individual adverse events (AEs) related to 3 studied doses of tirzepatide.

Methods

We performed a systematic review with meta-analysis including 5 databases (PubMed, Embase, CINAHL, Scopus, and Web of Science) for all clinical trials reporting AEs related to tirzepatide. The safety data from individual studies were extracted and analyzed through meta-regression to assess rates of individual AEs. Study quality assessment was performed using the National Heart, Lung, and Blood Institute Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies.

Results

Ten trials (6836 participants) were included. Gastrointestinal (GI) AEs were the most commonly reported AEs and were dose dependent 39% (95% CI, 35%-43%), 46% (95% CI, 42%-49%), and 49% (95% CI, 38%-60%) for the 5, 10, and 15 mg dose, respectively. Among all GI AEs, nausea and diarrhea were most frequent at any dose of tirzepatide. Drug discontinuation due to AEs was highest with the 15 mg dose of tirzepatide (10%). Incidence of mild hypoglycemia (blood glucose < 70 mg/dL) was highest with tirzepatide 10 mg dose 22.6% (9.2%-39.8%). Rates of fatal AEs, severe hypoglycemia, acute pancreatitis, cholelithiasis, and cholecystitis were extremely low (≤ 1%) across all doses of tirzepatide.

Conclusion

Tirzepatide is associated with a dose-dependent increase in incidence of GI AEs and AEs leading to drug discontinuation. Severe hypoglycemia, fatal AEs, acute pancreatitis, cholelithiasis, and cholecystitis are rare with this medication.

Change in pharmacodynamic variables following once-weekly tirzepatide treatment versus dulaglutide in Japanese patients with type 2 diabetes (SURPASS J-mono substudy)

AIM

To evaluate the pharmacodynamic effects of tirzepatide, a novel dual glucagon-like peptide-1 receptor and glucose-dependent insulinotropic polypeptide receptor agonist, compared with dulaglutide in patients with type 2 diabetes.

MATERIALS AND METHODS

SURPASS J-mono was a 52-week, multicentre, randomized, double-blind, parallel, active-controlled, Phase 3 study, conducted in Japan. This substudy of SURPASS J-mono evaluated postprandial metabolic variables and appetite after a meal tolerance test, and body composition measured by bioelectrical impedance analysis.

RESULTS

Of 636 participants in SURPASS J-mono, 48 were included in this substudy and assigned to tirzepatide 5 mg (n = 9), tirzepatide 10 mg (n = 11), tirzepatide 15 mg (n = 9), or dulaglutide 0.75 mg (n = 19). Participants had a mean (standard deviation) age of 58.6 (7.5) years, duration of diabetes of 6.0 (6.3) years, and body mass index of 27.5 (3.5) kg/m² . Mean glycated haemoglobin at baseline was 66 mmol/mol (8.22%). Following a standardized meal test, statistically significant differences in change from baseline in area under the concentration versus time curve from time zero to 6 h after dose for glucose, insulin, glucagon, C-peptide and triglycerides were observed in all tirzepatide treatment arms, except triglycerides at 10 mg, compared with dulaglutide at Week 32. For body composition, tirzepatide 10 mg and 15 mg resulted in a significant reduction in body weight, and all doses of tirzepatide resulted in a significant reduction in body fat mass at Week 52.

CONCLUSIONS

Compared with dulaglutide, tirzepatide showed greater potential for normalizing metabolic factors after a standardized meal. Tirzepatide reduced body weight and body fat mass.

Long-term cost-effectiveness analysis of tirzepatide versus semaglutide 1.0 mg for the management of type 2 diabetes in the United States

AIM

To evaluate the long-term cost-effectiveness of tirzepatide (5, 10 and 15 mg doses), a novel glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist, versus semaglutide 1.0 mg, an injectable glucagon-like peptide-1 receptor agonist, based on the results of the head-to-head SURPASS-2 trial, from a US healthcare payer perspective.

MATERIALS AND METHODS

The PRIME Type 2 Diabetes Model was used to make projections of clinical and cost outcomes over a 50-year time horizon. Baseline cohort characteristics, treatment effects and adverse event rates were derived from the 40-week SURPASS-2 trial. Intensification to insulin therapy occurred when HbA1c reached 7.5%, in line with American Diabetes Association recommendations. Direct costs in 2021 US dollars (US$) and health state utilities were derived from published sources. Future costs and clinical benefits were discounted at 3% annually.

RESULTS

All three doses of tirzepatide were associated with lower diabetes-related complication rates, improved life expectancy, improved quality-adjusted life expectancy and higher direct costs versus semaglutide. This resulted in incremental cost-effectiveness ratios of US$ 75 803, 58 908 and 48 785 per quality-adjusted life year gained for tirzepatide 5, 10 and 15 mg, respectively, versus semaglutide. Tirzepatide remained cost-effective versus semaglutide over a range of sensitivity analyses.

CONCLUSIONS

Long-term projections based on the SURPASS-2 trial results indicate that 5, 10 and 15 mg doses of tirzepatide are likely to be cost-effective versus semaglutide 1.0 mg for the treatment of type 2 diabetes in the United States.

Links between Metabolic Syndrome and Hypertension: The Relationship with the Current Antidiabetic Drugs

Hypertension poses a significant burden in the general population, being responsible for increasing cardiovascular morbidity and mortality, leading to adverse outcomes. Moreover, the association of hypertension with dyslipidaemia, obesity, and insulin resistance, also known as metabolic syndrome, further increases the overall cardiovascular risk of an individual. The complex pathophysiological overlap between the components of the metabolic syndrome may in part explain how novel antidiabetic drugs express pleiotropic effects. Taking into consideration that a significant proportion of patients do not achieve target blood pressure values or glucose levels, more efforts need to be undertaken to increase awareness among patients and physicians. Novel drugs, such as incretin-based therapies and renal glucose reuptake inhibitors, show promising results in decreasing cardiovascular events in patients with metabolic syndrome. The effects of sodium-glucose co-transporter-2 inhibitors are expressed at different levels, including renoprotection through glucosuria, natriuresis and decreased intraglomerular pressure, metabolic effects such as enhanced insulin sensitivity, cardiac protection through decreased myocardial oxidative stress and, to a lesser extent, decreased blood pressure values. These pleiotropic effects are also observed after treatment with glucagon-like peptide-1 receptor agonists, positively influencing the cardiovascular outcomes of patients with metabolic syndrome. The initial combination of the two classes may be the best choice in patients with type 2 diabetes mellitus and multiple cardiovascular risk factors because of their complementary mechanisms of action. In addition, the novel mineralocorticoid receptor antagonists show significant cardio-renal benefits, as well as anti-inflammatory and anti-fibrotic effects. Overall, the key to better control of hypertension in patients with metabolic syndrome is to consider targeting multiple pathogenic mechanisms, using a combination of the different therapeutic agents, as well as drastic lifestyle changes. This article will briefly summarize the association of hypertension with metabolic syndrome, as well as take into account the influence of antidiabetic drugs on blood pressure control.

Tirzepatide suppresses palatable food intake by selectively reducing preference for fat in rodents

AIM

To investigate the role of glucose-dependent insulinotropic polypeptide receptor (GIPR) agonists alone or combined with glucagon-like peptide-1 receptor (GLP-1R) agonists to regulate palatable food intake and the role of specific macronutrients in these preferences.

METHODS

To understand this regulation, we treated mice and rats on several choice diet paradigms of chow and a palatable food option with individual or dual GIPR and GLP-1R agonists.

RESULTS

In mice, the dual agonist tirzepatide suppressed total caloric intake, while promoting the intake of chow over a high fat/sucrose diet. Surprisingly, GIPR agonism alone did not alter food choice. The food intake shift observed with tirzepatide in wild-type mice was completely absent in GLP-1R knockout mice, suggesting that GIPR signalling does not regulate food preference. Tirzepatide also selectively suppressed the intake of palatable food but not chow in a rat two-diet choice model. This suppression was specific to lipids, as GLP-1R agonist and dual agonist treatment in rats on a choice paradigm assessing individual palatable macronutrients robustly inhibited the intake of Crisco (lipid) without decreasing the intake of a sucrose (carbohydrate) solution.

CONCLUSIONS

Decreasing preference for high-caloric, high-fat foods is a powerful action of GLP-1R and dual GIPR/GLP-1R agonist therapeutics, which may contribute to the weight loss success of these drugs.

Obesity pharmacotherapy: incretin action in the central nervous system

The prevalence of obesity is rising, creating an urgent need for efficacious therapies. Recent clinical trials show that tirzepatide, a dual agonist of receptors for the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), yields more weight loss than selective GLP-1 receptor (GLP-1R) agonists. Incretin receptors in the central nervous system (CNS) may contribute to these effects. Yet exactly how each receptor regulates body weight from within the CNS is not clearly understood. It remains especially unclear how GIP receptor (GIPR) signalling contributes to the effects of tirzepatide because both stimulation and inhibition of CNS GIPRs yield weight loss in preclinical models. We summarise current knowledge on CNS incretin receptor pharmacology to provide insight into the potential mechanisms of action of dual GIPR/GLP-1R agonists, with tirzepatide as the exemplar. In addition, we discuss recent developments in incretin-based dual- and tri-agonism for inducing weight loss in obese individuals.

Effect of dual glucose-dependent insulinotropic peptide/glucagon-like peptide-1 receptor agonist on weight loss in subjects with obesity

The occurrence of obesity is an increasing issue worldwide, especially in industrialized countries. Weight loss is important both to treat obesity and to prevent the development of complications. Currently, several drugs are used to treat obesity, but their efficacy is modest. Thus, new anti-obesity treatments are needed. Recently, there has been increased interest in the development of incretins that combine body-weight-lowering and glucose-lowering effects. Therefore, a new drug that simultaneously coactivates both the glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) and the glucagon-like peptide-1 receptor (GLP-1R) has been developed. Tirzepatide, the first in this class, improves glycemic control by increasing insulin sensitivity and lipid metabolism as well as by reducing body weight. Combining the activation of the two receptors, greater improvement of β-cell function offers more effective treatment of diabetes and obesity with fewer adverse effects than selective GLP-1R agonists. In the present review, we discuss the progress in the use of GIPR and GLP-1R coagonists and review literature from in vitro studies, animal studies, and human trials, highlighting the synergistic mechanisms of tirzepatide.

A systematic review of the safety of tirzepatide-a new dual GLP1 and GIP agonist - is its safety profile acceptable?

AIMS

Tirzepatide is a novel dual glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide-1 receptor agonist (GLP-1 RA). At present, there is no controversy over its effectiveness, but its safety. We conducted a systematic review to assess the safety of tirzepatide.

METHODS

We searched PubMed, Embase and Cochrane databases for randomized controlled trials (RCTs) of tirzepatide from databases inception to August 28, 2022 and used the Cochrane Systematic Assessment Manual Risk of Bias Assessment Tool (version 5.1) and modified Jadad scale to assess risk of bias. The systematic review was conducted via Revman5.4.

RESULTS

Nine RCTs with a total of 9818 patients were included. The overall safety profile of tirzepatide is similar to GLP-1RAs, except for the hypoglycemia (tirzepatide 15mg, pooled RR=3.83, 95% CI [1.19- 12.30], P=0.02) and discontinuation (tirzepatide 10mg, pooled RR=1.75,95%CI[1.16-2.63], P=0.007 and 15mg, pooled RR=2.03, 95%CI [1.37-3.01], P=0.0004). It also showed that the dose escalation could not rise the occurrence rates of total, severe, gastrointestinal adverse events and hypoglycemia (P>0.05); Compared with 5mg, tirzepatide 10mg and 15mg were associated with more frequent nausea (P<0.001), discontinuation (P<0.05) and injection-site reaction (P<0.01); The rates of vomiting and diarrhea were dose-dependence at the range of 5-15mg.

CONCLUSION

The safety profile of tirzepatide is generally acceptable, similar to GLP-1 RAs. It is necessary to pay attention to its specific adverse events (hypoglycemia and discontinuation) at high doses (10mg or higher). Nausea, vomiting, diarrhea, discontinuation and injection-site reaction were dose-dependence among specific dose ranges.As the heterogeneity in different studies by interventions, the results may be with biases and the further confirmation is needed. Meanwhile, more well-designed trials are needed to control the confounding factors and ensure adequate sample size.

Tirzepatide-Friend or Foe in Diabetic Cancer Patients?

It is a well-accepted fact that obesity and diabetes increase the risk of incidence of different cancers and their progression, leading to a decrease in the quality of life among affected cancer patients. In addition to decreasing the risk of cancers, maintaining a healthy body mass index (BMI)/body weight and/or blood glucose levels within the normal range critically impacts the response to anti-cancer therapy among affected individuals. A cancer patient managing their body weight and maintaining blood glucose control responds better to anti-cancer therapy than obese individuals and those whose blood glucose levels remain higher than normal during therapeutic intervention. In some cases, anti-diabetic/glucose-lowering drugs, some of which are also used to promote weight loss, were found to possess anti-cancer potential themselves and/or support anti-cancer therapy when used to treat such patients. On the other hand, certain glucose-lowering drugs promoted the cancer phenotype and risked cancer progression when used for treatment. Tirzepatide (TRZD), the glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide/gastric inhibitory peptide (GIP) agonist, has recently gained interest as a promising injectable drug for the treatment of type 2 diabetes and was approved by the FDA after successful clinical trials (SURPASS 1/2/3/4 and 5, NCT03954834, NCT03987919, NCT03882970, NCT03730662, and NCT04039503). In addition, the reports from the SURMOUNT-1 clinical trial (NCT04184622) support the use of TRZD as an anti-obesity drug. In the current review article, we examine the possibility and molecular mechanisms of how TRZD intervention could benefit cancer therapeutics or increase the risk of cancer progression when used as an anti-diabetic drug in diabetic patients.

Efficacy and safety of tirzepatide in patients with type 2 diabetes: A systematic review and meta-analysis

Purpose: A systematic review and meta-analysis was conducted to combine the data available from clinical trials and evaluate the clinical efficacy and safety of tirzepatide in people with type 2 diabetes (T2D). Methods: We systematically searched the MEDLINE, Embase, Cochrane Library, and clinical trials registries (https://clinicaltrials.gov) up to 25 March 2022 for randomized controlled trials (RCTs) that compared tirzepatide with placebo or active hypoglycemic drugs in subjects with T2D. Heterogeneity was judged by the I ² value and Cochran's Q test. The randomized effects model was adopted to calculate risk ratios and weighted mean differences (WMDs). The primary outcome was the change from baseline in HbA1c levels. Secondary efficacy endpoints were fasting serum glucose (FSG), change of body weight, blood pressure, fasting lipid profiles, and safety indexes. Results: Six trials comprising 6,579 subjects (4,410 in the tirzepatide group and 2,054 in the control group) fulfilled the pre-specified criteria and were included in the study. Tirzepatide treatment resulted in reducing HbA1c (WMD: -1.07%; 95% confidence intervals [CIs]: -1.44, -0.56), FSG (WMD, -21.50 mg/dl; 95% CI: -34.44, -8.56), body weight (WMD: -7.99 kg; 95% CI -11.36, -4.62), and blood pressure and ameliorated fasting lipid profiles, without increasing hypoglycemia, either as monotherapy or an add-on therapy. Tirzepatide increased the risk of gastrointestinal adverse events mainly in add-on therapy but not in terms of pancreatitis or cholelithiasis. Furthermore, tirzepatide presented a dose-response effect on the reduction in HbA1c and body weight and increase in nausea and vomiting. Conclusion: In patients with type 2 diabetes, tirzepatide shows superior blood glucose control and weight loss performance, without an increased risk of hypoglycemia. Systematic Review Registration: (https://www.crd.york.ac.uk/PROSPERO), identifier (CRD42022319442).

Efficacy of tirzepatide 5, 10 and 15 mg versus semaglutide 2 mg in patients with type 2 diabetes: An adjusted indirect treatment comparison

AIM

To conduct an adjusted indirect treatment comparison (aITC) of the efficacy of tirzepatide 5/10/15 mg versus semaglutide 2 mg in patients with type 2 diabetes.

MATERIALS AND METHODS

The primary analysis was a Bucher aITC of the change from baseline at week 40 in HbA1c (%) and body weight (kg). Aggregate data from the SURPASS-2 study that met the HbA1c inclusion criterion of the SUSTAIN FORTE study and from SUSTAIN FORTE metformin-only treated patients were used for primary analysis.

RESULTS

The SURPASS-2 refined population comprised 238/245/240 and 240 participants for tirzepatide 5/10/15 mg and semaglutide 1 mg, respectively. The SUSTAIN FORTE metformin-only population comprised 222 and 227 participants for semaglutide 1 and 2 mg, respectively. In this aITC, tirzepatide 10 and 15 mg significantly reduced HbA1c versus semaglutide 2 mg with an estimated treatment difference (ETD) of -0.36% (95% confidence interval [CI] -0.63, -0.09) and -0.4% (95% CI -0.67, -0.13), respectively. Tirzepatide 10 and 15 mg significantly reduced body weight versus semaglutide 2 mg with an ETD of -3.15 kg (95% CI -4.84, -1.46) and -5.15 kg (95% CI -6.85, -3.45), respectively. There were no significant differences between tirzepatide 5 mg and semaglutide 2 mg on change from baseline in HbA1c and body weight.

CONCLUSIONS

In this aITC, HbA1c and weight reductions were significantly greater for tirzepatide 10 and 15 mg versus semaglutide 2 mg and were similar for tirzepatide 5 mg versus semaglutide 2 mg. These findings provide comparative effectiveness insights in the absence of a head-to-head clinical trial.

Designing a Dual GLP-1R/GIPR Agonist from Tirzepatide: Comparing Residues Between Tirzepatide, GLP-1, and GIP

Improving type 2 diabetes using incretin analogues is becoming increasingly plausible. Currently, tirzepatide is the most promising listed incretin analogue. Here, I briefly explain the evolution of drugs of this kind, analyze the residue discrepancies between tirzepatide and endogenous incretins, summarize some existing strategies for prolonging half-life, and present suggestions for future research, mainly involving biased functions. This review aims to present some useful information for designing a dual glucagon like peptide-1 receptor/glucose-dependent insulinotropic polypeptide receptor agonist.

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