Reasons for discontinuation of GLP1 receptor agonists: data from a real-world cross-sectional survey of physicians and their patients with type 2 diabetes

NPYR modulation: Potential for the next major advance in obesity and type 2 diabetes management?

The approval of the glucagon-like peptide 1 (GLP-1) mimetics semaglutide and liraglutide for management of obesity, independent of type 2 diabetes (T2DM), has initiated a resurgence of interest in gut-hormone derived peptide therapies for the management of metabolic diseases, but side-effect profile is a concern for these medicines. However, the recent approval of tirzepatide for obesity and T2DM, a glucose-dependent insulinotropic polypeptide (GIP), GLP-1 receptor co-agonist peptide therapy, may provide a somewhat more tolerable option. Despite this, an increasing number of non-incretin alternative peptides are in development for obesity, and it stands to reason that other hormones will take to the limelight in the coming years, such as peptides from the neuropeptide Y family. This narrative review outlines the therapeutic promise of the neuropeptide Y family of peptides, comprising of the 36 amino acid polypeptides neuropeptide Y (NPY), peptide tyrosine-tyrosine (PYY) and pancreatic polypeptide (PP), as well as their derivatives. This family of peptides exerts a number of metabolically relevant effects such as appetite regulation and can influence pancreatic beta-cell survival. Although some of these actions still require full translation to the human setting, potential therapeutic application in obesity and type 2 diabetes is conceivable. However, like GLP-1 and GIP, the endogenous NPY, PYY and PP peptide forms are subject to rapid in vivo degradation and inactivation by the serine peptidase, dipeptidyl-peptidase 4 (DPP-4), and hence require structural modification to prolong circulating half-life. Numerous protective modification strategies are discussed in this regard herein, alongside related impact on biological activity profile and therapeutic promise.

Once-daily oral small-molecule glucagon-like peptide-1 receptor agonist lotiglipron (PF-07081532) for type 2 diabetes and obesity: Two randomized, placebo-controlled, multiple-ascending-dose Phase 1 studies

AIM

To investigate the effects of lotiglipron (PF-07081532), a once-daily, oral small-molecule glucagon-like peptide-1 receptor agonist, in participants with type 2 diabetes (T2D) and/or obesity.

MATERIALS AND METHODS

Two Phase 1 randomized, double-blind, placebo-controlled, multiple-ascending-dose studies were conducted to investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of lotiglipron.

RESULTS

Across the studies, 74 participants with T2D were treated for 28 or 42 days, and 26 participants with obesity without diabetes were treated for 42 days, following randomization to placebo or lotiglipron (target doses 10-180 mg/day, with dose titration to higher target doses). Most adverse events were mild (89.6%), with nausea the most frequently reported in both studies. There were no clinically meaningful adverse trends noted in safety laboratory tests, vital signs, or electrocardiogram parameters. In participants with T2D, lotiglipron resulted in dose-dependent reductions in mean daily glucose. The 180-mg dose was associated with least squares mean decreases from baseline in glycated haemoglobin (-1.61% [90% confidence interval {CI} -2.08, -1.14] vs. -0.61% [-1.56, 0.34] for placebo) and body weight (-5.10 kg [90% CI -6.62, -3.58] vs. -2.06 kg [90% CI -4.47, 0.36] for placebo) after 42 days; a similar magnitude of weight loss was seen in participants with obesity. The observed pharmacokinetic profile supported once-daily dosing.

CONCLUSIONS

The profile of once-daily lotiglipron with doses up to 180 mg, as observed in these two Phase 1 studies, indicated a safety and tolerability profile consistent with the mechanism of action, with dose-dependent reductions in glycaemic indices (T2D) and body weight (both populations) after multiple doses.

CLINICALTRIALS

gov identifier: NCT04305587, NCT05158244.

Curbing the Obesity Epidemic: Should GLP-1 Receptor Agonists Be the Standard of Care for Obesity?

PURPOSE OF REVIEW

This article summarizes the medical management of obesity with an emphasis on incretin-based therapeutics that target the neuro-hormonal basis of obesity.

RECENT FINDINGS

Medications that mimic the effect of incretins, a group of peptide hormones released in response to nutrient intake that regulate appetite, result in potent and durable weight loss. Glucagon-like peptide 1 (GLP-1) agonists and glucose-dependent insulinotropic polypeptide (GIP) agonists such as semaglutide and tirzepatide are approved by the United States Food and Drug Administration (FDA) for the management of obesity. The SELECT trial demonstrated that semaglutide led to a reduction in major adverse cardiovascular events in patients without diabetes who were either overweight and had preexisting cardiovascular disease or obese.

SUMMARY

The treatment of obesity is critical to prevent the progression of cardiovascular-kidney-metabolic syndrome. Incretin-based therapies offer remarkable weight loss and reduce major cardiovascular adverse events.

Addressing the Burden of Multiple Daily Insulin Injections in Type 2 Diabetes with Insulin Pump Technology: A Narrative Review

The growing prevalence of type 2 diabetes (T2D) remains a leading health concern in the US. Despite new medications and technologies, glycemic control in this population remains suboptimal, which increases the risk of poor outcomes, increased healthcare resource utilization, and associated costs. This article reviews the clinical and economic impacts of suboptimal glycemic control in patients on basal-bolus insulin or multiple daily injections (MDI) and discusses how new technologies, such as tubeless insulin delivery devices, referred to as "patch pumps", have the potential to improve outcomes in patients with T2D.

Underuse of GLP-1 receptor agonists in the management of type 2 diabetes despite a favorable benefit-safety profile

INTRODUCTION

Patients with type 2 diabetes (T2DM) are at high risk of atherosclerotic cardiovascular disease (ASCVD) and cardiovascular death. Cardiovascular protection is a key objective in T2DM.

AREAS COVERED

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have proven their efficacy in reducing major cardiovascular events in high-risk patients with T2DM in placebo-controlled trials, a finding confirmed in observational studies compared with other glucose-lowering agents. Overall, GLP-1RAs have a good safety profile associated with a favorable benefit/risk ratio for the management of T2DM, even if their cost-effectiveness might be questionable. International guidelines recommend GLP-1RAs as preferred glucose-lowering agents in patients with ASCVD and as a valuable alternative in overweight/obese patients with T2DM. However, real-life studies worldwide revealed that only a minority of patients receive a GLP-1RA, despite a positive trend for increased prescriptions in recent years. Surprisingly, however, fewer patients with established ASCVD are treated with these cardioprotective antihyperglycemic agents versus patients without ASCVD.

EXPERT OPINION

The reasons for GLP-1RA underuse in clinical practice are multiple. Multifaceted and coordinated interventions targeting all actors of the health-care system must be implemented to stimulate the adoption of GLP-1RAs as part of routine cardiovascular care among patients with T2DM, especially in those with ASCVD.

An endogenous GLP-1 circuit engages VTA GABA neurons to regulate mesolimbic dopamine neurons and attenuate cocaine seeking

Recent studies show that systemic administration of a glucagon-like peptide-1 receptor (GLP-1R) agonist is sufficient to attenuate the reinstatement of cocaine-seeking behavior, an animal model of relapse. However, the neural mechanisms mediating these effects and the role of endogenous central GLP-1 signaling in cocaine seeking remain unknown. Here, we show that voluntary cocaine taking decreased plasma GLP-1 levels in rats and that chemogenetic activation of GLP-1-producing neurons in the nucleus tractus solitarius (NTS) that project to the ventral tegmental area (VTA) decreased cocaine reinstatement. Single nuclei transcriptomics and FISH studies revealed GLP-1Rs are expressed primarily on GABA neurons in the VTA. Using in vivo fiber photometry, we found that the efficacy of a systemic GLP-1R agonist to attenuate cocaine seeking was associated with increased activity of VTA GABA neurons and decreased activity of VTA dopamine neurons. Together, these findings suggest that targeting central GLP-1 circuits may be an effective strategy toward reducing cocaine relapse and highlight a novel functional role of GABAergic GLP-1R-expressing midbrain neurons in drug seeking.

Five-Year Incidence of Progression to Osteoarthritis and Total Joint Arthroplasty in Patients Prescribed Glucagon-Like Peptide 1 Receptor Agonists

BACKGROUND

Research has suggested that glucagon-like peptide-1 receptor agonists (GLP-1-RAs) may have therapeutic effects on osteoarthritis of the hip and knee, in addition to managing diabetes and obesity. However, there is a lack of understanding regarding the association between GLP-1-RA use and the diagnosis of osteoarthritis (OA) of the hip and knee.

METHODS

A collaborative network analytics platform was queried for obese diabetic (n = 1,094,198), obese nondiabetic (n = 916,235), and nonobese diabetic (n = 157,305) patients who had an index visit between 2015 and 2017. Patients who had pre-existing hip and/or knee OA were excluded. A 1:1 propensity score matching was used to balance GLP-1-RA use in stratified cohorts for age, sex, race, body mass index, and hemoglobin A1c. The primary outcomes were rates of progression to hip OA, knee OA, major joint injections, total hip arthroplasty, and total knee arthroplasty. Cox proportional hazards models determined hazard ratios (HRs) between cohorts prescribed and not prescribed GLP-1-RAs.

RESULTS

All patients had a five-year follow-up. Rates of progression to hip and knee OA were higher among the GLP-1-RA users in both obese diabetic (hip HR: 1.63, 95% confidence interval [CI]: 1.46 to 1.82; knee HR: 1.52, CI: 1.41 to 1.64) and nonobese diabetic (hip HR: 1.78, CI: 1.50 to 2.10; knee HR: 1.58, CI: 1.39 to 1.80) cohorts. These diabetic cohorts received higher rates of major joint injections, though there was no difference in rates of total hip arthroplasty or total knee arthroplasty. No differences in five-year outcomes were seen when comparing obese, nondiabetic patients who were prescribed GLP-1-RAs with obese, nondiabetic patients not exposed to GLP-1-RAs.

CONCLUSIONS

This five-year analysis found a greater risk of progression to hip and knee OA among obese and non-obese diabetic GLP-1-RA users. Further studies should explore GLP-1-RA effects upon glucose management, weight loss, and lower extremity arthritis development.

LEVEL OF EVIDENCE

III, retrospective cohort study.

Initiating GLP-1 Therapy in Combination with FreeStyle Libre Provides Greater Benefit Compared with GLP-1 Therapy Alone

Background and Aim: Glucagon-like peptide-1 receptor agonists (GLP-1 RA) therapy provides glycemic benefits to individuals with type 2 diabetes (T2D). However, the effects of GLP-1 RA therapy in combination with FreeStyle Libre systems (FSL) are unknown. This study aimed to compare changes in hemoglobin A1c (HbA1c) between people acquiring GLP-1 with FSL (GLP-1+FSL) versus GLP-1 without FSL (GLP-1). Methods: This real-world study used Optum's de-identified Market Clarity Data, a linked electronic health records (EHR)-claims database, and included adults with T2D and HbA1c ≥8% who acquired their first GLP-1 RA medication between 2018 and 2022. GLP-1+FSL subjects acquired their first FSL within ±30 days of their first GLP-1 acquisition. Cohorts were matched 1:5 on baseline insulin therapy, age, sex, baseline HbA1c, and GLP-1 type. Paired changes in HbA1c were compared between unmatched and matched groups at 6 months. Results: The study included 24,724 adults in the unmatched cohort (GLP-1+FSL, n = 478; GLP-1, n = 24,246). The matched cohort included 478 GLP-1+FSL users and 2,390 GLP-1 users: mean age 53.5 ± 11.8 and 53.5 ± 11.3 years, HbA1c 10.25 ± 1.68% and 10.22 ± 1.69%, respectively. HbA1c reduction was greater in the GLP-1+FSL group compared with the GLP-1 group in the unmatched cohort (-2.43% vs. -1.73%, difference 0.70%, P < 0.001, respectively) and in the matched cohort (-2.43% vs. -2.06%, difference 0.37%, P < 0.001). GLP-1+FSL vs. GLP-1 treatment was associated with greater HbA1c reduction in the intensive insulin (-2.32% vs. -1.50%), nonintensive insulin (-2.50% vs. -1.74%), and noninsulin group (-2.46% vs. -1.78%), as well as in patients using semaglutide (-2.73% vs. -1.92%) and dulaglutide (-2.45% vs. -1.71%) GLP-1 RA, all P < 0.001. Conclusions: Adults with suboptimally controlled T2D, initiating GLP-1 RA with FreeStyle Libre, had greater improvement in HbA1c compared with those treated with GLP-1 RA only. These results suggest an additional glycemic benefit of FSL when used with a GLP-1 RA in T2D treatment.

The Current and Future Role of Insulin Therapy in the Management of Type 2 Diabetes: A Narrative Review

Early initiation of intensive insulin therapy has been demonstrated to be effective in controlling glycemia and possibly preserving beta-cell function. Innovations in insulin formulations and delivery systems continue. However, we have seen an acceleration in the development of new classes of diabetes medications for individuals with type 2 diabetes and obesity, such as, for example, glucagon-like peptide-1 receptor agonists (GLP-1 RAs). These formulations have been shown to confer significant benefits in achieving good glycemic control with reduced hypoglycemia risk, weight loss, and cardiorenal protection. Therefore, it is reasonable to question whether there is still a role for insulin therapy in the management of type 2 diabetes. However, there are clear limitations inherent to GLP-1 RA therapy, including high rates of suboptimal adherence and treatment discontinuation due to high cost and side effects, which diminish long-term efficacy, and supply issues. In addition, newer formulations have shown improvements in convenience and tolerability, and have been shown to be even more effective when used in conjunction with basal insulin. In this narrative review, we discuss current evidence that supports GLP-1 RA use in combination with insulin therapy and the potential pitfalls of reliance on GLP-1 RAs as a substitute for insulin therapy.

Effects of age and disease duration on the efficacy and safety of iGlarLixi in Asian people with type 2 diabetes: A post hoc analysis of the LixiLan-O-AP and LixiLan-L-CN trials

AIM

To evaluate the effect of age and disease duration on the efficacy and safety of iGlarLixi versus insulin glargine 100 units/ml (iGlar) or lixisenatide (Lixi) alone in Asian people with type 2 diabetes (T2D) uncontrolled on oral antidiabetic drugs (LixiLan-O-AP) or basal insulin ± oral antidiabetic drugs (LixiLan-L-CN).

MATERIALS AND METHODS

In this post hoc analysis, the glycated haemoglobin (HbA1c) changes were assessed from baseline to week 24 (LixiLan-O-AP) or 30 (LixiLan-L-CN) in subgroups defined by baseline age (<65, ≥65 years) and duration of T2D. The proportion who achieved the composite of HbA1c <7% (<53.0 mmol/mol) without weight gain and without symptomatic hypoglycaemia (plasma glucose ≤3.9 mmol/L) and the incidences of hypoglycaemia and gastrointestinal disorders were also analysed.

RESULTS

HbA1c reductions were consistently greater with iGlarLixi versus iGlar or Lixi across all subgroups, including participants aged ≥65 years and those with T2D for ≥15 or ≥20 years. Greater proportions of participants achieved HbA1c <7% (<53.0 mmol/mol) without weight gain or hypoglycaemia with iGlarLixi versus iGlar or Lixi, regardless of age or T2D duration. Hypoglycaemia incidence was similar with iGlarLixi versus iGlar across most subgroups; the incidence of gastrointestinal disorders was lower with iGlarLixi versus Lixi in all subgroups.

CONCLUSIONS

iGlarLixi showed consistent efficacy and safety across all age and disease duration subgroups in Asian people with uncontrolled T2D, including older individuals and those with longstanding disease.

Opportunities to overcome underutilization of enhanced insulin delivery technologies in people with type 2 diabetes: a narrative review

Use of innovative technologies such as continuous glucose monitoring (CGM) and insulin delivery systems have been shown to be safe and effective in helping patients with diabetes achieve significantly improved glycemic outcomes compared to their previous therapies. However, these technologies are underutilized in many primary care practices. This narrative review discusses some of the clinical and economic benefits of tubeless insulin delivery devices and discusses how this technology can overcome the main obstacles inherent to use of conventional insulin delivery devices.

The antiemetic actions of GIP receptor agonism

Nausea and vomiting are primitive aspects of mammalian physiology and behavior that ensure survival. Unfortunately, both are ubiquitously present side effects of drug treatments for many chronic diseases with negative consequences on pharmacotherapy tolerance, quality of life, and prognosis. One of the most critical clinical examples is the profound emesis and nausea that occur in patients undergoing chemotherapy, which continue to be among the most distressing side effects, even with the use of modern antiemetic medications. Similarly, antiobesity/diabetes medications that target the glucagon-like peptide-1 system, despite their remarkable metabolic success, also cause nausea and vomiting in a significant number of patients. These side effects hinder the ability to administer higher dosages for optimal glycemic and weight management and represent the major reasons for treatment discontinuation. Our inability to effectively control these side effects highlights the need to anatomically, molecularly, and functionally characterize novel neural substrates that drive and inhibit nausea and emesis. Here, we discuss clinical and preclinical evidence that highlights the glucose-dependent insulinotropic peptide receptor system as a novel therapeutic central target for the management of nausea and emesis.

You may delay, but time will not. Beta cells lost are never found again: a case for timely initiation of basal insulin in type 2 diabetes

Since its first use just over a century ago, insulin treatment has evolved dramatically, such that the molecules are physiologic in nature, and treatment can now closely resemble the natural hormone response over 24 hours. Newer, longer-acting basal insulin analogs have provided insulin therapies with improved characteristics and, therefore, ease of use, and can readily be incorporated as part of routine treatment for type 2 diabetes (T2D), but evidence suggests that insulin remains underused in people with T2D. We review the barriers to initiation of basal insulin and the education needed to address these barriers, and we provide practical pointers, supported by evidence, for primary care physicians and advanced practice providers to facilitate timely initiation of basal insulin in the people with T2D who will benefit from such treatment.

G protein-coupled receptors driven intestinal glucagon-like peptide-1 reprogramming for obesity: Hope or hype?

'Globesity' is a foremost challenge to the healthcare system. The limited efficacy and adverse effects of available oral pharmacotherapies pose a significant obstacle in the fight against obesity. The biology of the leading incretin hormone glucagon-like-peptide-1 (GLP-1) has been highly captivated during the last decade owing to its multisystemic pleiotropic clinical outcomes beyond inherent glucoregulatory action. That fostered a pharmaceutical interest in synthetic GLP-1 analogues to tackle type-2 diabetes (T2D), obesity and related complications. Besides, mechanistic insights on metabolic surgeries allude to an incretin-based hormonal combination strategy for weight loss that emerged as a forerunner for the discovery of injectable 'unimolecular poly-incretin-agonist' therapies. Physiologically, intestinal enteroendocrine L-cells (EECs) are the prominent endogenous source of GLP-1 peptide. Despite comprehending the potential of various G protein-coupled receptors (GPCRs) to stimulate endogenous GLP-1 secretion, decades of translational GPCR research have failed to yield regulatory-approved endogenous GLP-1 secretagogue oral therapy. Lately, a dual/poly-GPCR agonism strategy has emerged as an alternative approach to the traditional mono-GPCR concept. This review aims to gain a comprehensive understanding by revisiting the pharmacology of a few potential GPCR-based complementary avenues that have drawn attention to the design of orally active poly-GPCR agonist therapy. The merits, challenges and recent developments that may aid future poly-GPCR drug discovery are critically discussed. Subsequently, we project the mechanism-based therapeutic potential and limitations of oral poly-GPCR agonism strategy to augment intestinal GLP-1 for weight loss. We further extend our discussion to compare the poly-GPCR agonism approach over invasive surgical and injectable GLP-1-based regimens currently in clinical practice for obesity.

Occurrence of Gastrointestinal Adverse Events Upon GLP-1 Receptor Agonist Initiation With Concomitant Metformin Use: A Post Hoc Analysis of LEADER, STEP 2, SUSTAIN-6, and PIONEER 6

OBJECTIVE

To assess the impact of concomitant metformin use on gastrointestinal adverse events during the initiation and titration of a glucagon-like peptide 1 receptor agonist (GLP-1RA).

RESEARCH DESIGN AND METHODS

Using data from four clinical trials of liraglutide and semaglutide (Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results [LEADER], Semaglutide Treatment Effect in People with Obesity [STEP 2], Trial to Evaluate Cardiovascular and Other Long-Term Outcomes With Semaglutide in Subjects With Type 2 Diabetes [SUSTAIN-6], and Peptide Innovation for Early Diabetes Treatment [PIONEER] 6), we compared the incidence of gastrointestinal adverse events during GLP-1RA initiation and titration in participants with and without concomitant metformin use.

RESULTS

Of 16,996 participants, 12,928 (76%) were treated with metformin. Concomitant metformin use did not increase the percentage of participants who developed gastrointestinal adverse events or their severity during the observation window. Among participants experiencing gastrointestinal adverse events, metformin use did not increase study product discontinuation. Within treatment arms (GLP-1RA and placebo), a numerically higher percentage of metformin nonusers experienced gastrointestinal adverse events and discontinued the study product compared with metformin users.

CONCLUSIONS

Concomitant metformin use does not increase occurrence of gastrointestinal symptoms during GLP-1RA initiation or impact GLP-1RA discontinuation.

Poly-Agonist Pharmacotherapies for Metabolic Diseases: Hopes and New Challenges

The use of glucagon-like peptide-1 (GLP-1) receptor-based multi-agonists in the treatment of type 2 diabetes and obesity holds great promise for improving glycaemic control and weight management. Unimolecular dual and triple agonists targeting multiple gut hormone-related pathways are currently in clinical trials, with recent evidence supporting their efficacy. However, significant knowledge gaps remain regarding the biological mechanisms and potential adverse effects associated with these multi-target agents. The mechanisms underlying the therapeutic efficacy of GLP-1 receptor-based multi-agonists remain somewhat mysterious, and hidden threats may be associated with the use of gut hormone-based polyagonists. In this review, we provide a critical analysis of the benefits and risks associated with the use of these new drugs in the management of obesity and diabetes, while also exploring new potential applications of GLP-1-based pharmacology beyond the field of metabolic disease.

Outcomes and Attributes Patients Value When Choosing Glucose-Lowering Medications: A Mixed-Methods Study

This mixed-methods study sought to identify pharmacotherapy preferences among 40 noninsulin-treated adults with type 2 diabetes receiving care at two U.S. health care systems. Participants ranked by relative importance various health outcomes and medication attributes and then contextualized their rankings. Most participants ranked blindness (63%), death (60%), heart attack (48%), and heart failure (48%) as the most important health outcomes and glucose-lowering efficacy (68%) as the most important medication attribute, followed by oral administration (45%) and lack of gastrointestinal side effects (38%).

Bromocriptine and Colesevelam Hydrochloride: Novel Therapies for Type II Diabetes Mellitus

The increasing prevalence of type II diabetes mellitus (T2DM) is a worldwide healthcare concern. Over the years, our understanding of T2DM has grown considerably in uncovering the pathophysiology of the disease and, in turn, understanding how improved treatment methods can be used to slow disease progression. Some long-term complications that are responsible for most T2DM mortalities include cardiovascular disease, neurological decline, and renal failure. In treating T2DM, it is important that not only glycemic control be obtained but also control of associated complications. Bromocriptine and colesevelam hydrochloride have both been approved by the Food and Drug Administration (FDA) to treat T2DM but are not readily used in practice. These medications are known to treat glycemic dysregulation via unconventional mechanisms, which might contribute to their potential to provide protection against common diabetic complications such as cardiovascular disease. In order to ensure that these overlooked medications become more readily used, it is vital that more research be performed to further elucidate their efficacy in a clinical setting. Future studies should continue to provide clinicians a better understanding of the role these medications have on the treatment of T2DM such as their ability to be used in combination with other commonly used T2DM medications or as monotherapies.

Real-world evidence generation from patients, their caregivers and physicians supporting clinical, regulatory and guideline decisions: an update on Disease Specific Programmes

OBJECTIVE

To update on and describe the role of Disease Specific Programmes (DSPs), a multi-perspective real-world data (RWD) source, in the context of the evolution of the value and acceptance of real-world evidence (RWE) in clinical, regulatory and guideline decision-making.

METHODS

DSPs are multi-national, multi-subscriber, multi-therapy cross-sectional surveys incorporating retrospective data collection from patient, caregiver and physician perspectives. Information collected covers the patient journey, including treatment/prescribing patterns and rationale, patient-reported outcomes, impact on work and everyday activities, attitudes towards and perceptions of the condition, adherence to treatment and burden of illness. Published peer-reviewed DSP papers were aligned with current key RWE themes identified in the literature, alongside their contribution to RWE.

RESULTS

RWE themes examined were: using RWE to inform clinical practice, patient and caregiver engagement, RWE role in supporting health technology assessments and regulatory submissions, informing value-driven healthcare decisions, real-world patient subgroup differences and therapeutic inertia/unmet needs; highlighting patients' and caregivers' experience of living with a disease, disconnect from their physicians, unmet needs and educational gaps.

CONCLUSIONS

DSPs provide a wealth of RWD in addition to evidence generated by registries, clinical trials and observational research, with wide use for the pharmaceutical industry, government, funding/regulatory bodies, clinical practice guideline insights and, most importantly, informing improvements in people's lives. The depth, breadth and heritage of information collected via DSPs since 1995 is unparalleled, extending understanding of how diseases are managed by physicians in routine clinical practice and why treatment choices are made, patients' perceptions of their disease management, and caregiver burden.

Safety and efficacy of the new, oral, small-molecule, GLP-1 receptor agonists orforglipron and danuglipron for the treatment of type 2 diabetes and obesity: systematic review and meta-analysis of randomized controlled trials

AIMS

The present systematic review aimed to synthesize available data from recently published randomized trials (RCTs) investigating the efficacy and safety of the novel, orally administered, small-molecule glucagon-like peptide 1 receptor agonists (GLP-1RAs) orforglipron and danuglipron for the treatment of type 2 diabetes mellitus (T2DM), obesity or both.

METHODS

Literature search was performed through Medline (via PubMed), Cochrane Library and Scopus until August 16, 2023. Double-independent study selection, data extraction and quality assessment were performed. Evidence was pooled with random effects meta-analysis.

RESULTS

Totally, 1037 patients among seven RCTs were analyzed. All RCTs had low risk of bias according to the Cochrane Collaboration tool (RoB2). Novel GLP-1RAs led to significant reduction in HbA1c in patients with T2DM compared to controls (MD = -1.03 %; 95 % CI = [-1.29, -0.77]; P < 0.001). A significantly greater weight reduction was also noted both in patients with T2DM or obesity compared to controls (MD = -3.26 kg; 95 % CI = [-4.79, -1.72]; P < 0.001 and MD = -7.52 kg; 95 % CI = [-14.63, -0.41]; P = 0.038, respectively; P for subgroup differences = 0.25). Regarding safety, novel GLP-1RAs showed a neutral effect on the odds of severe hypoglycemia or serious adverse events (OR = 0.34; 95 % CI = [0.09, 1.31]; P = 0.11 and OR = 0.95; 95 % CI = [0.39, 2.34]; P = 0.91, respectively) and significantly higher odds of gastrointestinal, treatment-emergent adverse events (OR = 2.57; 95 % CI = [1.49, 4.42]; P < 0.001) and adverse events leading to discontinuation (OR = 2.89; 95 % CI = [1.22, 6.87]; P = 0.016).

CONCLUSION

Preliminary evidence supports that orforglipron and danuglipron are efficient in glycemic control and weight reduction in T2DM, obesity or both. More longitudinal research is warranted in order to provide deeper insights into their efficacy, safety and tolerability before their potential incorporation in the pharmacological arsenal against T2DM or obesity.

PYY3-36 infused systemically or directly into the VTA attenuates fentanyl seeking in male rats

More effective treatments for fentanyl use disorder are urgently needed. An emerging literature indicates that glucagon-like peptide-1 receptor (GLP-1R) agonists attenuate voluntary opioid taking and seeking in rodents. However, GLP-1R agonists produce adverse malaise-like effects that may limit patient compliance. Recently, we developed a dual agonist of GLP-1Rs and neuropeptide Y2 receptors (Y2Rs) that attenuates fentanyl taking and seeking at doses that do not produce malaise-like effects in opioid-experienced rats. Whether activating Y2Rs alone is sufficient to reduce opioid taking and seeking, however, is not known. Here, we investigated the efficacy of the Y2R ligand PYY3-36 to reduce fentanyl self-administration and the reinstatement of fentanyl-seeking behavior, a model of relapse in humans. Male rats were allowed to self-administer fentanyl (2.5 μg/kg, i.v.) for 21 days on a fixed-ratio 5 (FR5) schedule of reinforcement. Rats were then pretreated with vehicle or PYY3-36 (50 μg/kg s.c.; 0.1 and 1.0 μg/100 nL intra-VTA) prior to fentanyl self-administration test sessions. There were no effects of systemic or intra-VTA PYY3-36 on intravenous fentanyl self-administration. Opioid taking was then extinguished. Prior to subsequent reinstatement test sessions, rats were pretreated with vehicle or PYY3-36 (50 μg/kg s.c.; 0.1 and 1.0 μg/100 nL intra-VTA). Both systemic and intra-VTA administration of PYY3-36 attenuated fentanyl reinstatement in male rats at doses that did not affect food intake or produce adverse malaise-like effects. These findings indicate that Y2R agonism alone is sufficient to decrease fentanyl-seeking behavior during abstinence in opioid-experienced rats and further support strategies aimed at targeting Y2Rs for treating opioid use disorders.

Evaluating Glycemic Control Efficacy and Safety of the Oral Small Molecule Glucagon-Like Peptide 1 Receptor Agonist Danuglipron in Type 2 Diabetes Patients: A Systemic Review and Meta-Analysis

Introduction

Diabetes Mellitus (DM) is a significant global health concern, with Type 2 DM (T2DM) being highly prevalent. Glucagon-Like Peptide 1 receptor agonists (GLP-1RA), such as Danuglipron, offer potential benefits in T2DM management. This meta-analysis examines the safety and efficacy of Danuglipron, focusing on adverse outcomes and glycemic parameters.

Methods

A systematic search was conducted in PubMed, Scopus, and Cochrane Library for RCTs involving Danuglipron till August 2023, following PRISMA guidelines. The Cochrane risk-of-bias tool was used for quality assessment. Adverse outcomes (diarrhea, nausea, vomiting, headache, decreased appetite, dyspepsia, dizziness) and glycemic parameters like changes in HbA1C, fasting plasma glucose (FPG), and body weight were analyzed.

Results

Four RCTs published from 2021 to 2023 were included. Both doses of Danuglipron were associated with diarrhea (RR=2.66, 90% CI: 1.32 to 5.35, p=0.02), nausea (RR=5.5, 90% CI: 3.4 to 8.88, p<0.00001), and vomiting (RR=5.98, 90% CI: 2.93 to 12.23, p=0.0001). The 120mg dose showed decreased appetite (RR=3.46, 90% CI: 1.57 to 7.62, p=0.01), dyspepsia (RR=4.04, 90% CI: 1.93 to 8.43, p=0.002), and dizziness (RR=5.08, 90% CI: 1.45 to 17.82, p=0.03). Reductions in HbA1C (SMD -1.09, 90% CI -1.39 to -0.8, p < 0.00001), FPG (SMD -1.10, 90% CI -1.46 to -0.75, p < 0.00001), and body weight (SMD -1.08, 90% CI -1.42 to -0.74, p < 0.00001) were observed for both doses.

Conclusion

Danuglipron demonstrates potential for glycemic control and weight reduction in T2DM. Adverse outcomes include diarrhea, nausea, vomiting, and decreased appetite, with dose-related effects. Clinicians must weigh benefits against side effects when considering Danuglipron for T2DM management.

Endogenous glucagon-like peptide (GLP)-1 as alternative for GLP-1 receptor agonists: Could this work and how?

In recent years, we have witnessed the many beneficial effects of glucagon-like peptide (GLP)-1 receptor agonists, including the reduction in cardiovascular risk in patients with type 2 diabetes, and the reduction of body weight in those with obesity. Increasing evidence suggests that these agents differ considerably from endogenous GLP-1 when it comes to their routes of action, although their clinical effects appear to be the same. Given the limitations of the GLP-1 receptor agonists, could it be useful to develop agents which stimulate GLP-1 release? Here we will discuss the differences and similarities between GLP-1 receptor agonists and endogenous GLP-1, and will detail how endogenous GLP-1-when stimulated appropriately-could have clinically relevant effects.

Synergistic Combinations of Gut- and Pancreas-Hormone-Based Therapies: Advancements in Treatments for Metabolic Diseases

Metabolic diseases, such as obesity, type 2 diabetes mellitus (T2DM), cardiovascular disease, and liver disease, have become increasingly prevalent around the world. As an alternative to bariatric surgery, glucagon-like peptide 1 (GLP-1) receptor agonists have been at the forefront of weight loss medication to combat these metabolic complications. Recently, there has been an exciting rapid emergence of new weight loss medications that combine GLP-1 receptor (GLP-1R) agonists with other gut- and pancreatic-derived hormones, such as glucose-dependent insulinotropic polypeptide (GIP) and glucagon (GCG) receptor agonists. Dual-agonist (GLP-1/GIP and GLP-1/GCG) and tri-agonist (GLP-1/GIP/GCG) administration generally result in greater weight loss, reduction of blood sugar and lipid levels, restoration of tissue function, and improvement in whole-body substrate metabolism compared to when GLP-1R agonists are used alone. The aim of this review is to summarize the recent literature of both preclinical and clinical studies on how these emerging gut-peptide therapies further improve weight loss and metabolic health outcomes for various metabolic diseases.

Glucagon-Like Peptide-1 Receptor Agonists for Chronic Weight Management

Rates of obesity have risen over the past few decades. Subsequently, the popularity of the pharmaceutical weight-loss drug market has grown over the past few years to meet growing demand. Among the most commonly prescribed drugs for weight management, many are glucagon-like peptide-1 receptor agonists (GLP-1 agonists) which are also utilized for the management of type 2 diabetes. There is a substantial and growing body of research comparing the efficacy of different clinical trials and examining long-term safety. This literature review examines the rise of off-label prescribing practices in the management of weight, with a focus on GLP-1 agonists. Physicians and patients should be aware of the unique aspects of existing treatment options, the impacts of off-label prescribing, and the effects of these medications. This review emphasizes the importance of informed decision-making, as well as the need for further research to guide future clinical practice.

Combining Celiac and Hepatic Vagus Nerve Neuromodulation Reverses Glucose Intolerance and Improves Glycemic Control in Pre- and Overt-Type 2 Diabetes Mellitus

Neurological disorders and type 2 diabetes mellitus (T2DM) are deeply intertwined. For example, autonomic neuropathy contributes to the development of T2DM and continued unmanaged T2DM causes further progression of nerve damage. Increasing glycemic control has been shown to prevent the onset and progression of diabetic autonomic neuropathies. Neuromodulation consisting of combined stimulation of celiac vagal fibers innervating the pancreas with concurrent electrical blockade of neuronal hepatic vagal fibers innervating the liver has been shown to increase glycemic control in animal models of T2DM. The present study demonstrated that the neuromodulation reversed glucose intolerance in alloxan-treated swine in both pre- and overt stages of T2DM. This was demonstrated by improved performance on oral glucose tolerance tests (OGTTs), as assessed by area under the curve (AUC). In prediabetic swine (fasting plasma glucose (FPG) range: 101-119 mg/dL) the median AUC decreased from 31.9 AUs (IQR = 28.6, 35.5) to 15.9 AUs (IQR = 15.1, 18.3) p = 0.004. In diabetic swine (FPG range: 133-207 mg/dL) the median AUC decreased from 54.2 AUs (IQR = 41.5, 56.6) to 16.0 AUs (IQR = 15.4, 21.5) p = 0.003. This neuromodulation technique may offer a new treatment for T2DM and reverse glycemic dysregulation at multiple states of T2DM involved in diabetic neuropathy including at its development and during progression.

Efficacy and safety of once-daily oral semaglutide 25 mg and 50 mg compared with 14 mg in adults with type 2 diabetes (PIONEER PLUS): a multicentre, randomised, phase 3b trial

BACKGROUND

Once-daily oral semaglutide is an effective type 2 diabetes treatment. We aimed to investigate a new formulation of oral semaglutide at higher investigational doses versus the approved 14 mg dose in adults with inadequately controlled type 2 diabetes.

METHODS

This global, multicentre, randomised, double-blind, phase 3b trial, carried out at 177 sites in 14 countries, enrolled adults with type 2 diabetes, glycated haemoglobin (HbA1c) 8·0-10·5% (64-91 mmol/mol), a BMI of 25·0 kg/m2 or greater, receiving stable daily doses of one to three oral glucose-lowering drugs. Participants were randomly assigned (1:1:1), by means of an interactive web response system, to once-daily oral semaglutide 14 mg, 25 mg, or 50 mg for 68 weeks. Investigators, site personnel, trial participants, and trial sponsor staff were masked to dose assignment throughout the trial. The primary endpoint was change in HbA1c from baseline to week 52, evaluated with a treatment policy estimand in the intention-to-treat population. Safety was assessed in all participants who received at least one dose of trial drug. This trial is registered with ClinicalTrials.gov, NCT04707469, and the European Clinical Trials register, EudraCT 2020-000299-39, and is complete.

FINDINGS

Between Jan 15 and Sept 29, 2021, of 2294 people screened, 1606 (n=936 [58·3%] male; n=670 [41·7%] female; mean [SD] age 58·2 [10·8] years) received oral semaglutide 14 mg (n=536), 25 mg (n=535), or 50 mg (n=535). At baseline, mean (SD) HbA1c was 9·0% (0·8; 74·4 mmol/L [SD 8·3]) and mean bodyweight was 96·4 kg (21·6). Mean changes (SE) in HbA1c at week 52 were -1·5 percentage points (SE 0·05) with oral semaglutide 14 mg, -1·8 percentage points (0·06) with 25 mg (estimated treatment difference [ETD] -0·27, 95% CI -0·42 to -0·12; p=0·0006), and -2·0 percentage points (0·06) with 50 mg (ETD -0·53, -0·68 to -0·38; p<0·0001). Adverse events were reported by 404 (76%) participants in the oral semaglutide 14 mg group, 422 (79%) in the 25 mg group, and 428 (80%) in the 50 mg group. Gastrointestinal disorders, which were mostly mild to moderate, occurred more frequently with oral semaglutide 25 mg and 50 mg than with 14 mg. Ten deaths occurred during the trial; none were judged to be treatment related.

INTERPRETATION

Oral semaglutide 25 mg and 50 mg were superior to 14 mg in reducing HbA1c and bodyweight in adults with inadequately controlled type 2 diabetes. No new safety concerns were identified.

FUNDING

Novo Nordisk.

Regurgitation under anesthesia in a fasted patient prescribed semaglutide for weight loss: a case report

PURPOSE

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) such as semaglutide are a class of medications prescribed to treat type 2 diabetes mellitus, and more recently, as an adjunct for weight loss because of its effects of delaying gastric emptying and suppressing appetite. Semaglutide is a long-acting agent with a half-life of approximately one week, and there are currently no guidelines that address the perioperative management of such agents.

CLINICAL FEATURES

We describe an unexpected case of regurgitation of a large volume of gastric contents upon induction of general anesthesia in a nondiabetic, nonobese patient despite a long preoperative fasting period (20 hr for solids and eight hours for clear fluids). This patient had no traditional risk factors for regurgitation or aspiration but was taking the GLP-1 RA semaglutide for weight loss and had last taken the medication two days before their scheduled procedure.

CONCLUSIONS

Patients taking long-acting GLP-1 RAs such as semaglutide may be at risk of pulmonary aspiration under anesthesia. We propose strategies to mitigate this risk including holding the medication four weeks prior to a scheduled procedure when feasible and considering full stomach precautions.

Bridging the gap in cardiovascular care in diabetic patients: are cardioprotective antihyperglycemic agents underutilized?

INTRODUCTION

Atherosclerotic cardiovascular disease (ASCVD) and heart failure (HF) are two major complications of type 2 diabetes (T2DM). Cardiovascular protection is a key objective, yet not fully reached in clinical practice.

AREAS COVERED

Both glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2is) have proven their efficacy in reducing major cardiovascular events in high-risk patients with T2DM and SGLT2is in reducing hospitalization for HF in placebo-controlled randomized trials. However, real-life studies worldwide revealed that only a minority of patients with T2DM receive either a GLP-1RA or an SGLT2i and surprisingly even less patients with established ASCVD or HF are treated with these cardioprotective antihyperglycemic agents.

EXPERT OPINION

Bridging the gap between evidence-based cardiovascular protection with GLP-1RAs and SGLT2is and their underuse in daily clinical practice in patients with T2DM at high risk is crucial from a public health viewpoint. However, the task appears hazardous and the goal not attained considering the current failure. Education of specialists/primary care physicians and patients is critical. Multifaceted and coordinated interventions involving all actors (physicians, patients and broadly health-care system) must be implemented to stimulate the adoption of these cardioprotective antihyperglycemic medications as part of routine cardiovascular care among patients with T2DM.

Discovery of Novel 5,6-Dihydro-1,2,4-triazine Derivatives as Efficacious Glucagon-Like Peptide-1 Receptor Agonists

Danuglipron is the most representative small-molecule agonist of the glucagon-like peptide-1 receptor (GLP-1R) and has received considerable attention due to positive results in the treatment of type 2 diabetes mellitus (T2DM) and obesity in clinical trials. However, hERG inhibition, lower activity than endogenous GLP-1, and a short action time represent limitations in terms of feasible application. In this study, we report a new class of 5,6-dihydro-1,2,4-triazine derivatives that serve to eliminate potential hERG inhibition caused by the piperidine ring of danuglipron. Applying systematic in vitro to in vivo screening, we have identified compound 42 as a highly potent and selective GLP-1R agonist, which delivers improved (7-fold) efficacy in stimulating cAMP accumulation compared with danuglipron and which exhibits acceptable drug-like properties. Furthermore, 42 significantly reduces glucose excursion and inhibits food intake of hGLP-1R Knock-In mice. These effects are longer-lasting than that shown by danuglipron, demonstrating feasibility in the treatment of T2DM and obesity.

Glycemic Control and the Weight Benefit of a Daily 7 mg Dose of Oral Semaglutide Versus an Alternate-Day 14 mg Dose of Oral Semaglutide From an Ambulatory Glucose Monitoring Data: A Retrospective Cohort Study From Eastern India

INTRODUCTION

Oral semaglutide is a glucagon-like peptide-1 receptor agonist (GLP-1RA) class of antidiabetic medication. High costs and GI side effects are the major limitations of its widespread use. Some patients who were on a 14 mg dose of oral semaglutide self-prescribed an alternate-day schedule to mitigate GI side effects and to reduce the cost.

METHODS

This retrospective observational cohort study evaluates the ambulatory glucose profile (AGP) data, extrapolated glycosylated hemoglobin (HbA1C), and BMI of 11 types of 2 diabetes mellitus (T2DM) while they were on an alternate-day 14 mg dose of oral semaglutide compared to their record while on a daily 7 mg dose. The AGP metrics (time-in-range (TIR), time-below-range (TBR), and time-above-range (TAR)) along with extrapolated HbA1C and BMI were analyzed. Statistical analysis was done using SPSS Statistics version 21.0.

RESULTS

No statistically significant difference in the AGP metrics between the AGP profile of a daily 7 mg dose and the AGP profile of an alternate-day 14 mg dose of oral semaglutide was observed. Interestingly, a statistically significant progressive decline in BMI value was observed even on the alternate-day 14 mg dose when compared to the daily 7 mg dose.

CONCLUSION

In this small cohort of patients, the metrics of short-term glycemic control and the extrapolated HbA1C values were similar for the daily 7 mg dose versus the alternate-day 14 mg dose of oral semaglutide. BMI showed progressive reduction which was statistically significant even with the alternate-day 14 mg dose of oral semaglutide.

[Efficacy of treatment with glucagon-like peptide receptor agonists-1 in Asian patients with type 2 diabetes mellitus]

BACKGROUND

The projected 68% increase in patients with type 2 diabetes mellitus (T2D) in the upcoming decades and the specific pathophysiological course of the disease are critical factors for the development of optimal disease management tactics in the Asian population. It is now known that β-cell dysfunction is dominant in the pathogenesis of T2D in Asians. In a number of Asian countries, incretin therapy is the leading therapy.

AIM

To review literature on glucagon-like peptide-1 (GLP-1) secretion and clinical trial results of GLP-1 receptor agonist class (GLP-1RA) drugs as well as to evaluate their effectiveness in Asian population with T2D.

MATERIALS AND METHODS

A review of studies on pathophysiological aspects of GLP-1 secretion and evaluation of the efficacy of therapy with GLP-1RA preparations registered and used in clinical practice in Asian regions.

RESULTS

Several studies in Asian countries have shown that intact GLP-1 levels were significantly lower in both T2D patients and healthy Japanese volunteers; as well as in patients with impaired glucose tolerance. It is suggested that either impaired secretion of GLP-1 in the gut, accelerated processing by dipeptidyl peptidase-4, or a combination of both are responsible for the decrease in GLP-1. The greater efficacy of GLP-1RA treatment in achieving glycemic control in Asian T2D patients was presented by Kim Y.G. et al. in a meta-analysis of 15 randomised controlled trials, the reduction in HbA1c on GLP-1RA treatment averaged -1.16% in Asian-dominated studies and -0.83% in non-Asian-dominated studies. In the PIONEER 9 clinical programme, similar results were obtained, with oral semaglutide having a more pronounced effect on glycaemic control in Japanese patients. Thus, the mean change in HbA 1c was -1.1%, 7 mg -1.5%, and 14 mg -1.7% at the 3 mg dose; whereas in the PIONEER 1 study in the global population, the mean change in HbA1c was -0.6%, -0.9% and -1.1% for 3, 7, 14 mg semaglutide, respectively. The PIONEER 10 study concluded that oral semaglutide was well tolerated by Japanese patients with T2D. Oral semaglutide reduced HbA1c (14 mg dose) and body weight (7 and 14 mg doses) more significantly compared to dulaglutide at 0.75 mg dose. Results of a pooled analysis of long-acting GLP-1RA showed a more significant reduction in cardiovascular event risk in the Asian subpopulation.

CONCLUSION

The presented review describes benefits in glycemic control as well as in the reduction of relative cardiovascular event risks with GLP-1RA treatment in the Asian population, which requires further in-depth research and implies optimal management tactics in patients with T2DM.

Early Insight Into the Retrospective Data of a Case Series on Type 2 Diabetes Mellitus on Alternate-Day Dosing of Oral Semaglutide: Utopia or Reality?

Introduction Oral semaglutide, with a long half-life of seven days, is the first oral-based peptide drug and is used as an antidiabetic for the reduction of glycosylated hemoglobin (HbA1c). Oral semaglutide, like other glucagon-like peptide-1 receptor agonists (GLP1RAs), is costly and has gastrointestinal (GI) side effects, especially with a 14 mg dose. In the real world, some type 2 diabetes mellitus (T2DM) patients on 14 mg oral dose adopt an alternate-day strategy to minimize unwanted GI symptoms. In this study, we analyzed the ambulatory glucose profile (AGP) data of patients with T2DM who were on 14 mg alternate-day oral semaglutide therapy. Methods This retrospective observational study evaluated the AGP data of 10 patients on alternate-day dosing of 14 mg oral semaglutide. The AGP data over a period of 14 days on a single group of patients were analyzed without any control group or randomization and are presented as a case series. AGP monitoring, using Freestyle Libre Pro (Abbott, Illinois, United States), is a standard operating procedure of the endocrinology department for all T2DM patients who were put on oral semaglutide therapy. The AGP data of the glycemic parameters time-in-range (TIR), time-above-range (TAR), and time-below-range (TBR), were compared between the days when oral semaglutide was consumed (days-on-drug) versus the days when oral semaglutide was not consumed (days-off-drug). The statistical analysis was done with Statistical Package for Social Sciences (SPSS) version 21.0 (IBM Corp., Armonk, NY). Results We applied the Shapiro-Wilk test (sample size <50) for normality testing; the TIR values of days-on-drug and days-off-drug showed high p values (p =0.285 and 0.109), respectively. This indicated that TIR values days-on-drug and days-off-drug were normally distributed. Although, the distribution of TAR and TBR values days-on-drug and days-off-drug, were not normal as they had small p values (p< 0.05). Hence, further analysis of the paired set of data was done using the Wilcoxon signed-rank test. It revealed no difference in TIR, TAR, and TBR between the two groups (days-on-drug and days-off-drug). Conclusion Throughout the period of observation, the glycemic metrics (TIR, TAR, and TBR) remained steady with a 14 mg alternate-day oral semaglutide regimen.

GLP-1/GIP analogues: potential impact in the landscape of obesity pharmacotherapy

INTRODUCTION

: Obesity is recognised as a major healthcare challenge. Following years of slow progress in discovery of safe, effective therapies for weight management, recent approval of the glucagon-like peptide 1 receptor (GLP-1R) mimetics, liraglutide and semaglutide, for obesity has generated considerable excitement. It is anticipated these agents will pave the way for application of tirzepatide, a highly effective glucose-dependent insulinotropic polypeptide receptor (GIPR), GLP-1R co-agonist recently approved for management of type 2 diabetes mellitus.

AREAS COVERED

: Following promising weight loss in obese individuals in Phase III clinical trials, liraglutide and semaglutide were approved for weight management without diabetes. Tirzepatide has attained Fast Track designation for obesity management by the US Food and Drug Association. This narrative review summarises experimental, preclinical and clinical data for these agents and related GLP-1R/GIPR co-agonists, prioritising clinical research published within the last 10 years where possible.

EXPERT OPINION

: GLP-1R mimetics are often discontinued within 24-months, owing to gastrointestinal side-effects, meaning long-term application of these agents in obesity is questioned. Combined GIPR/GLP-1R agonism appears to induce fewer side-effects, indicating GLP-1R/GIPR co-agonists may be more suitable for enduring obesity management. After years of debate, this GIPR-biased GLP-1R/GIPR co-agonist highlights the therapeutic promise of including GIPR modulation for diabetes and obesity therapy.

GLP-1 Agonists for Weight Loss: Pharmacology and Clinical Implications

This review investigates the various pharmacologic treatments for overweight and obesity in adults, especially glucagon-like peptide 1 (GLP-1) agonists. In light of the globally expanding obesity pandemic and the limited selection of treatments, physicians must be equipped with knowledge regarding proven medications and their nuanced differences to best support patients on their path to a healthier lifestyle. In this review, we explore the current medical therapies for obesity, including all major categories, individual mechanisms of action, pharmacokinetics and pharmacodynamics, adverse effects, risks, and absolute contraindications. Additionally, we review the evidence of four recent clinical trials, two systematic reviews, and two meta-analyses describing the efficacy of GLP-1 agonists in decreasing weight, lowering HbA1c, and improving obesity comorbidities. We also discuss total cost and cost-effectiveness compared to other categories, long-term adherence, barriers to use, and reasons for discontinuation of this drug category. Our goal is that this review can serve as a framework to aid providers in building their knowledge and selecting the most advantageous weight loss medication for each patient.

Management of metabolic-associated fatty liver disease: The diabetology perspective

The metabolic syndrome as a consequence of the obesity pandemic resulted in a substantial increase in the prevalence of metabolic-associated fatty live disease (MAFLD) and type 2 diabetes mellitus (T2DM). Because of the similarity in pathobiology shared between T2DM and MAFLD, both disorders coexist in many patients and may potentiate the disease-related outcomes with rapid progression and increased complications of the individual diseases. In fact, awareness about this coexistence and the risk of complications are often overlooked by both hepatologists and diabetologists. Management of these individual disorders in a patient should be addressed wholistically using an appropriate multidisciplinary team approach involving both the specialists and, when necessary, liaising with dieticians and surgeons. This comprehensive review is to compile the current evidence from a diabetologist's perspective on MAFLD and T2DM and to suggest optimal management strategies.

Efficacy and Safety of Tirzepatide in Adults With Type 2 Diabetes: A Perspective for Primary Care Providers

This article reviews the efficacy and safety data of tirzepatide, a once-weekly, novel glucose-dependent insulinotropic polypeptide and glucagon-like peptide 1 (GLP-1) receptor agonist approved in the United States, the European Union, and other regions for the treatment of type 2 diabetes. All doses of tirzepatide demonstrated superiority in reducing A1C and body weight from baseline versus placebo or active comparators. The safety profile of tirzepatide was consistent with that of the GLP-1 receptor agonist class, with mild to moderate and transient gastrointestinal side effects being the most common adverse events. With clinically and statistically significant reductions in A1C and body weight without increased risk of hypoglycemia in various populations, tirzepatide has demonstrated potential as a first-in-class treatment option for many people with type 2 diabetes.

Association of the gallbladder or biliary diseases with dipeptidyl peptidase 4 inhibitors in patients with type 2 diabetes: a meta-analysis of randomized controlled trials

BACKGROUND

Previous studies have shown inconsistent conclusions regarding the association between incretin-based therapies and the risk of developing gallbladder or biliary diseases. We conducted a meta-analysis to evaluate the risk of gallbladder or biliary diseases associated with dipeptidyl peptidase 4 inhibitors (DPP4i) in patients with type 2 diabetes.

METHODS

The PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were searched (from inception up to March 14, 2022) for published randomized controlled trials (RCTs) that compared DPP4i with placebo or other glucose-lowering drugs in patients with type 2 diabetes. The outcomes of interest were cholecystitis, cholangitis, cholelithiasis, bile duct stones, and biliary colic. Relative risks (RRs) and 95% confidence intervals (CI) were pooled using a random-effects model. Subgroup analyses were performed according to patient age, trial duration, and types of DPP4i.

RESULTS

In total, 97,150 participants from 75 eligible RCTs were included in the meta-analysis. DPP4i were associated with an increased risk of composite of gallbladder or biliary diseases (RR 1.20 [95% CI 1.01-1.42]) and cholecystitis (RR 1.38 [95% CI 1.08-1.75]). Among all included trials, DPP4i showed no association with the following manifestations of gallbladder or biliary diseases: cholelithiasis (RR 1.00 [95% CI 0.76-1.32]), cholangitis (RR 0.81 [95% CI 0.39-1.66]), bile duct stones (RR 1.08 [95% CI 0.57-2.05]), and biliary colic (RR 0.72 [95% CI 0.23-2.25]). Subgroup analyses showed that DPP4i were associated with a higher risk of cholecystitis in older patients (RR 1.37 [95% CI 1.03-1.83]) compared with younger patients (RR 1.08 [95% CI 0.89-2.18]) and in those with a longer duration of drug use (RR 1.43 [95% CI 1.08-1.89]) compared with shorter use (RR 1.23 [95% CI 0.74-2.03]).

CONCLUSIONS

This systematic review and meta-analysis of RCTs found that the use of DPP4i was associated with an increased risk of cholecystitis, especially in patients of advanced age or in those who were exposed to the drugs for a long period of time.

Treatment-Related Attributes of Diabetes Therapies and How People with Type 2 Diabetes Report Their Impact on Indicators of Medication-Taking Behaviors

Purpose

Understanding the treatment-related attributes influencing medication-taking behaviors in people with type 2 diabetes (T2D) is important for delivery of patient-centered care. This review aimed to identify and summarize studies in which people with T2D (PwD) directly indicated the treatment-related attributes associated with medication-taking behaviors or intentions.

Materials and Methods

EMBASE and PubMed were searched for studies (Jan 2005-May 2021) reporting the link between PwD-expressed diabetes treatment-related attributes and the decision to initiate, adhere to, or discontinue a T2D medication. Eligible studies reported attributes associated with oral antidiabetes drugs or injectables (not insulin). Studies not explicitly exploring the link between attributes and indicators of behaviors (eg most discrete-choice experiments [DCE] and those interrogating electronic medical records or claims databases) were excluded, as were studies where the link between attribute and behavior came from anyone but the PwD.

Results

Of the 6464 studies identified, 16 were included. Studies were conducted across multiple countries; the USA was most represented (n = 8 studies). The impact of treatment attributes was described on indicators of initiation (n = 3), adherence (n = 12), and discontinuation (n = 4). Some studies evaluated multiple behaviors. PwD perspectives were solicited by structured questionnaires (n = 10), qualitative approaches (n = 4), or DCE explicitly exploring the link to medication-taking behaviors (n = 2). Closed- (n = 9) and open-ended questions (n = 7) were employed. Across studies, several factors including glycemic efficacy (n = 9), weight change (n = 9), dosing frequency (n = 9), hypoglycemia (n = 8), gastrointestinal adverse events (n = 8), regimen complexity (n = 6), route of administration (n = 3), and cardiovascular risk (n = 1) were reported as influencing behaviors, being motivators or barriers to initiation, adherence, or discontinuation.

Conclusion

Several attributes influence how PwD take their medications. Insights gained directly from PwD have the potential to assist stakeholders in making more informed, patient-centered, treatment decisions, thus choosing and managing medications that PwD are comfortable initiating and persisting with over the longer term.

Real-world outcomes of addition of insulin glargine 300 U/mL (Gla-300) to glucagon-like peptide-1 receptor agonist (GLP-1 RA) therapy in people with type 2 diabetes: The DELIVER-G study

AIMS

To provide real-world data on the addition of basal insulin (BI) in people with type 2 diabetes mellitus (PWD2) suboptimally controlled with glucagon-like peptide-1 receptor agonist (GLP-1RA) therapy. However, real-world data on the addition of BI to GLP-1RA therapy are limited.

MATERIALS AND METHODS

We used a US electronic medical record data source (IBM® Explorys®) that includes approximately 4 million PWD2 to assess the real-world impact of adding the second-generation BI analogue insulin glargine 300 U/mL (Gla-300) to GLP-1RA therapy. Insulin-naïve PWD2 receiving GLP-1RAs who also received Gla-300 between March 1, 2015 and September 30, 2019 were identified; participants were required to have data for ≥12 months before, and ≥6 months after, addition of Gla-300.

RESULTS

The mean (standard deviation [SD]) age of participants (N = 271) was 57.9 (10.8) years. Baseline glycated haemoglobin (HbA1c) was 9.16% and was significantly reduced (-0.97 [SD 1.60]%; P < 0.0001) after addition of Gla-300; a significant increase in the proportion of PWD2 achieving HbA1c control was observed after addition of Gla-300 (HbA1c <7.0%: 4.80% vs. 22.14%, P < 0.0001; HbA1c <8.0%: 19.56% vs. 51.29%, P < 0.0001). The incidence of overall (8.49% vs. 9.59%; P = 0.513) and inpatient/emergency department (ED)-associated hypoglycaemia (0.37% vs. 0.74%; P = 1.000), as well as overall (0.33 vs. 0.46 per person per year [PPPY]; P = 0.170) and inpatient/ED-associated hypoglycaemia events (0.01 vs. 0.04 PPPY; P = 0.466) were similar before and after addition of Gla-300.

CONCLUSIONS

In US real-world clinical practice, adding Gla-300 to GLP-1RA significantly improved glycaemic control without significantly increasing hypoglycaemia in PWD2. Further research into the effect of adding Gla-300 to GLP-1RA therapy is warranted.

Growth differentiation factor 15 (GDF15) and semaglutide inhibit food intake and body weight through largely distinct, additive mechanisms

AIMS

To evaluate whether the potent hypophagic and weight-suppressive effects of growth differentiation factor-15 (GDF15) and semaglutide combined would be a more efficacious antiobesity treatment than either treatment alone by examining whether the neural and behavioural mechanisms contributing to their anorectic effects were common or disparate.

MATERIALS/METHODS

Three mechanisms were investigated to determine how GDF15 and semaglutide induce anorexia: the potentiation of the intake suppression by gastrointestinal satiation signals; the reduction in motivation to feed; and the induction of visceral malaise. We then compared the effects of short-term, combined GDF15 and semaglutide treatment on weight loss to the individual treatments. Rat pharmaco-behavioural experiments assessed whether GDF15 or semaglutide added to the satiating effects of orally gavaged food and exogenous cholecystokinin (CCK). A progressive ratio operant paradigm was used to examine whether GDF15 or semaglutide reduced feeding motivation. Pica behaviour (ie, kaolin intake) and conditioned affective food aversion testing were used to evaluate visceral malaise. Additionally, fibre photometry studies were conducted in agouti-related protein (AgRP)-Cre mice to examine whether GDF15 or semaglutide, alone or in combination with CCK, modulate calcium signalling in hypothalamic AgRP neurons.

RESULTS

Semaglutide reduced food intake by amplifying the feeding-inhibitory effect of CCK or ingested food, inhibited the activity of AgRP neurons when combined with CCK, reduced feeding motivation and induced malaise. GDF15 induced visceral malaise but, strikingly, did not affect feeding motivation, the satiating effect of ingested food or CCK signal processing. Combined GDF15 and semaglutide treatment produced greater food intake and body weight suppression than did either treatment alone, without enhancing malaise.

CONCLUSIONS

GDF15 and semaglutide reduce food intake and body weight through largely distinct processes that produce greater weight loss and feeding suppression when combined.

A survey of physician experience and treatment satisfaction prescribing once-weekly semaglutide injections for patients with type 2 diabetes in Canada

We assessed physicians' experiences of prescribing once-weekly (OW) semaglutide to patients with type 2 diabetes (T2D) in Canada. Physicians who had prescribed OW semaglutide to ≥2 patients with T2D in the past 12 months and had been doing so for ≥3 months were surveyed during 1-17 October 2018. Prescribing reasons, treatment satisfaction and reasons for discontinuation were assessed. Of the 50 participants, 72% and 54% were prescribed OW semaglutide due to its superior glycemic control and effect on weight, respectively. Most physicians were more satisfied with injection frequency (62%), effect on weight (60%), achieving HbA1c target (54%) and therapy simplicity (50%) with OW semaglutide versus other glucagon-like peptide-1 receptor agonists. Treatment discontinuations in 13% of OW semaglutide-treated patients were reported by physicians, primarily due to gastrointestinal symptoms (70%). The survey suggests that physicians are satisfied with the OW semaglutide clinical effects. Video Abstract: http://links.lww.com/CAEN/A34.

National Trends in Use of Sodium-Glucose Cotransporter-2 Inhibitors and Glucagon-like Peptide-1 Receptor Agonists by Cardiologists and Other Specialties, 2015 to 2020

Background

Sodium‐glucose cotransporter‐2 inhibitors (SGLT2is) and glucagon‐like peptide‐1 receptor agonists (GLP‐1RAs) mitigate cardiovascular risk in individuals with type 2 diabetes, but most eligible patients do not receive them. We characterized temporal trends in SGLT2i and GLP‐1RA use by cardiologists compared with other groups of clinicians.

Methods and Results

We conducted a descriptive analysis of serial, cross‐sectional data derived from IQVIA’s National Prescription Audit, a comprehensive audit capturing ≈90% of US retail prescription dispensing and projected to population‐level data, to estimate monthly SGLT2is and GLP‐1RAs dispensed from January 2015 to December 2020, stratified by prescriber specialty and molecule. We also used the American Medical Association’s Physician Masterfile to calculate average annual SGLT2is and GLP‐1RAs dispensed per physician. Between January 2015 and December 2020, a total of 63.2 million SGLT2i and 63.4 million GLP‐1RA prescriptions were dispensed in the United States. Monthly prescriptions from cardiologists increased 12‐fold for SGLT2is (from 2228 to 25 815) and 4‐fold for GLP‐1RAs (from 1927 to 6981). Nonetheless, cardiologists represented only 1.5% of SGLT2i prescriptions and 0.4% of GLP‐1RA prescriptions in 2020, while total use was predominated by primary care physicians/internists (57% of 2020 SGLT2is and 52% of GLP‐1RAs). Endocrinologists led in terms of prescriptions dispensed per physician in 2020 (272 SGLT2is and 405 GLP‐1RAs). Cardiologists, but not noncardiologists, increasingly used SGLT2is over GLP‐1RAs, with accelerated uptake of empagliflozin and dapagliflozin coinciding with their landmark cardiovascular outcomes trials and subsequent US Food and Drug Administration label expansions.

Conclusions

While use of SGLT2is and GLP‐1RAs by cardiologists in the United States increased substantially over a 6‐year period, cardiologists still account for a very small proportion of all use, contributing to marked undertreatment of individuals with type 2 diabetes at high cardiovascular risk.

Association of formulary restrictions and initiation of an SGLT2i or GLP1-RA among Medicare beneficiaries with type 2 diabetes

BACKGROUND

Use of SGLT2 inhibitors (SGLT2i) and GLP-1 receptor agonists (GLP1-RA) among older adults with type 2 diabetes (T2D) has been limited.

OBJECTIVE

To examine factors associated with initiation of an SGLT2i or GLP-1RA among Medicare beneficiaries with T2D in the early years after their market approval, with a particular focus on formulary restrictions (e.g. prior authorization, step therapy requirements, higher co-pays).

METHODS

A retrospective cohort study using data from a 5% random sample of Medicare beneficiaries with T2D followed from 1/1/2015-12/31/16. Formulary restrictiveness was defined as: (1) the number of target drugs (i.e. SGLT2is or GLP1-RAs) included in tiers 1-3 of a beneficiary's formulary (greater number of drugs in tiers 1-3 being less restrictive) and (2) the number of drugs without prior authorization or step therapy (requirement to try less expensive drugs prior to "stepping up" to more expensive therapies). We used multivariable logistic regression models to estimate the association between measures of formulary restrictiveness and initiation of a target drug, controlling for patient demographics, diabetes duration, clinical comorbidities, and provider specialty.

RESULTS

Among 112,985 beneficiaries with T2D, 5,619 (5%) initiated an SGLT2i or GLP1-RA. After adjusting for baseline characteristics, patients enrolled in formularies with ≥ 2 target drugs available in tiers 1-3 had 17% higher odds of initiating an SGLT2i or GLP1-RA (aOR 1.17, 95% CI 1.05-1.31) compared to patients enrolled in formularies with 0 drugs available in tiers 1-3. There was no significant association between the number of drugs without prior authorization or step therapy requirements and initiation of a target drug (aOR 0.96, 95% CI, 0.85-1.09). Age 75 years or older (vs < 65, aOR 0.23, 95% CI 0.21-0.26) and black race (vs white, aOR 0.65, 95% CI 0.59-0.71) were associated with lower odds of initiating a target drug.

CONCLUSIONS

Having a greater number of target drugs available on less expensive formulary tiers is associated with increased odds of initiating an SGLT2i or GLP-1RA among Medicare beneficiaries with T2D.

Oral semaglutide in type 2 diabetes mellitus: Comprehensive review, critical appraisal and clinical consideration of its use in India

BACKGROUND AND AIMS

Oral semaglutide is the first glucagon-like petide-1 receptor agonist (GLP-1RA) approved for oral use in the treatment of type 2 diabetes mellitus (T2DM). We aim to conduct a comprehensive review of literature to find out the efficacy and safety of oral semaglutide in T2DM, to lay out a clinical consideration for its use in India.

METHODS

We searched the electronic database of PubMed and Google Scholar from inception until January 31, 2022, using several MeSH keywords and retrieved all available granular details of phase 1, 2 and 3 randomized controlled trials (RCTs) of oral semaglutide. Subsequently, we reviewed the results critically to lay down the clinical recommendation of its use.

RESULTS

Ten phase 3 randomized, placebo- and or active-controlled studies of oral semaglutide (PIONEER programs) are currently published. Seven global trials of oral semaglutide (PIONEER 1-5, 7 and 8) that exclusively studied the efficacy (lowering of HbA1c and body weight, achieving target of HbA1c <7% and other composites of HbA1c and weight) outcomes, found 14 mg oral semaglutide to be superior to placebo or active comparators (empagliflozin, sitagliptin and liraglutide). Efficacy was similar in Asians, although no separate data exists for Indians due to the low number of participants. Expectedly, gastrointestinal intolerance were the most commonly observed side effects with oral semaglutide and the main reason for drug discontinuation.

CONCLUSION

Oral semaglutide 14 mg is an effective agent in the treatment of T2DM. Real-world studies of semaglutide are clearly needed in India in absence of meaningful data from RCTs in Indians.

'For me, it didn't seem as drastic a step as being controlled by insulin': A qualitative investigation of expectations and experiences of non-insulin injectable therapy among adults with type 2 diabetes

AIMS

This qualitative study aims to explore beliefs, attitudes and experiences of injectable glucagon-like-peptide-1 receptor agonists (GLP-1RAs) use and discontinuation, as well as attitudes to further injectable treatment intensification, among adults with type 2 diabetes (T2D).

METHODS

Nineteen in-depth semi-structured interviews lasting (mean ± standard deviation) 45 ± 18 min were conducted, face-to-face (n = 14) or via telephone (n = 5). Transcripts were analysed using inductive template analyses. Eligible participants were English-speaking adults with T2D who had recently initiated (≤3 years) GLP-1RA treatment.

RESULTS

Participants were aged 28-72 years, who predominantly lived in metropolitan areas (n = 15), and had an experience of daily (n = 11) and/or once-weekly (n = 13) GLP-1RA formulations. Six participants had discontinued treatment and seven had trialled two or more formulations. Expectations and experiences of GLP-1RA were related to the perceived: (1) symbolism and stigma of injectable diabetes treatment; (2) ease of injectable administration and device preferences; (3) treatment convenience and social impact; (4) treatment efficacy and benefits, and; (5) negative treatment side effects. Some participants reported increased receptiveness to insulin therapy following their GLP-1RA experience, others emphasised unique concerns about insulin beyond injectable administration.

CONCLUSIONS

This study provides a novel understanding of expectations and experience of non-insulin injectables among Australian adults with T2D. Our data suggest expectations may be informed by attitudes to insulin therapy, while perceived treatment benefits (e.g. weight-related benefits, administration frequency) may motivate uptake and ongoing use despite concerns. Experience of GLP-1RA injections may impact receptiveness to future insulin use.

The therapeutic potential of GLP-1 receptor biased agonism

Glucagon-like peptide-1 (GLP-1) receptor agonists are effective treatments for type 2 diabetes as they stimulate insulin release and promote weight loss through appetite suppression. Their main side effect is nausea. All approved GLP-1 agonists are full agonists across multiple signalling pathways. However, selective engagement with specific intracellular effectors, or biased agonism, has been touted as a means to improve GLP-1 agonists therapeutic efficacy. In this review, I critically examine how GLP-1 receptor-mediated intracellular signalling is linked to physiological responses and discuss the implications of recent studies investigating the metabolic effects of biased GLP-1 agonists. Overall, there is little conclusive evidence that beneficial and adverse effects of GLP-1 agonists are attributable to distinct, nonoverlapping signalling pathways. Instead, G protein-biased GLP-1 agonists appear to achieve enhanced anti-hyperglycaemic efficacy by avoiding GLP-1 receptor desensitisation and downregulation, partly via reduced β-arrestin recruitment. This effect seemingly applies more to insulin release than to appetite regulation and nausea, possible reasons for which are discussed. At present, most evidence derives from cellular and animal studies, and more human data are required to determine whether this approach represents a genuine therapeutic advance. LINKED ARTICLES: This article is part of a themed issue on GLP1 receptor ligands (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.4/issuetoc.

Adherence and persistence rates of major antidiabetic medications: a review

The objective of this paper was to review the adherence and persistence rates of major antidiabetic medication classes (i.e., metformin, sulfonylureas, sodium glucose cotransporter-2 inhibitors, dipeptidyl peptidase-4 inhibitors, insulin, glucagon-like peptide-1 receptor agonists, and thiazolidinediones) by summarizing the major findings of the studies published since 2017. In addition, we reported the potential causes for low adherence and persistence of antidiabetic medications. Based on the literature, the highest rate of adherence and persistence was consistently observed in metformin users. Second to metformin were sodium glucose cotransporter-2 inhibitors. Injectable therapies such as insulin and glucagon-like peptide-1 receptor agonists trailed low on the adherence and persistence rates. To the best of our knowledge, no studies published since the year 2017 analyzed the adherence and persistence of thiazolidinediones independently. The most frequently cited cause for low adherence and persistence was the severity of adverse events. Baseline characteristics (e.g., baseline HbA1c level), demographic information (e.g., age, gender, or ethnicity), and comorbidity profiles also had significant impacts on adherence and persistence in patients with type 2 diabetes mellitus.

Weight Change and the Association with Adherence and Persistence to Diabetes Therapy: A Narrative Review

PURPOSE

Type 2 diabetes (T2D) medication adherence is poor and is impacted by individual drug characteristics. Treatment-associated weight change can affect medication-taking behavior. This review aimed to explore weight change on T2D therapy and consider its impact on adherence and discontinuation.

METHODS

Searches were conducted in MEDLINE and EMBASE (2005 to September 2020), and among recent congress abstract books for studies providing data on medication adherence or discontinuation and weight change in people with T2D (PwD).

RESULTS

Nine studies meeting the inclusion criteria were identified from 9188 bibliographic records. All three studies exploring weight change and discontinuation reported weight loss to be associated with higher persistence. Seven studies of varying design explored weight change and adherence. Four reported absolute weight change (kg) and adherence: one pooled data from different diabetes medications and demonstrated that self-reported adherence was significantly associated with weight loss; however, three studies found that weight change in adherent PwD was in the direction of the known weight profile (loss/gain) of the evaluated drug. Categorical weight loss (≥3%) and adherence were reported in two studies: one reported that numerically more adherent versus non-adherent PwD lost ≥3% weight regardless of the drug's weight profile, the other showed that early weight loss with a glucagon-like peptide-1 agonist was significantly associated with better adherence. One study reported adherence by categorical weight change; as weight loss increased, adherence scores improved, regardless of drug type.

CONCLUSION

Findings suggest that discontinuation rates may be lower in PwD who lose as compared to those who gain weight on T2D treatment. The evidence base on adherence and weight change is more challenging to interpret due to the range of study designs. Given the importance of weight control in T2D, further research exploring the individual's treatment, weight journey, and behaviors over time should be undertaken.

Hypophagia induced by salmon calcitonin, but not by amylin, is partially driven by malaise and is mediated by CGRP neurons

Objective

The behavioral mechanisms and the neuronal pathways mediated by amylin and its long-acting analog sCT (salmon calcitonin) are not fully understood and it is unclear to what extent sCT and amylin engage overlapping or distinct neuronal subpopulations to reduce food intake. We here hypothesize that amylin and sCT recruit different neuronal population to mediate their anorectic effects.

Methods

Viral approaches were used to inhibit calcitonin gene-related peptide (CGRP) lateral parabrachial nucleus (LPBN) neurons and assess their role in amylin’s and sCT’s ability to decrease food intake in mice. In addition, to test the involvement of LPBN CGRP neuropeptidergic signaling in the mediation of amylin and sCT’s effects, a LPBN site-specific knockdown was performed in rats. To deeper investigate whether the greater anorectic effect of sCT compared to amylin is due do the recruitment of additional neuronal pathways related to malaise multiple and distinct animal models tested whether amylin and sCT induce conditioned avoidance, nausea, emesis, and conditioned affective taste aversion.

Results

Our results indicate that permanent or transient inhibition of CGRP neurons in LPBN blunts sCT-, but not amylin-induced anorexia and neuronal activation. Importantly, sCT but not amylin induces behaviors indicative of malaise including conditioned affective aversion, nausea, emesis, and conditioned avoidance; the latter mediated by CGRP^LPBN neurons.

Conclusions

Together, the present study highlights that although amylin and sCT comparably decrease food intake, sCT is distinctive from amylin in the activation of anorectic neuronal pathways associated with malaise.

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CGRP neurons mediate the effect of the amylin agonist salmon calcitonin (sCT) on food intake.

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Amylin's hypophagic effect does not require CGRP neurons.

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sCT-induced anorexia but not amylin is associated with malaise.