Polyethylene glycol loxenatide (PEX168) in subjects with renal impairment: A pharmacokinetic study

Peptide GLP-1 receptor agonists: From injection to oral delivery strategies

Peptide glucagon-like peptide-1 receptor agonists (GLP-1RAs) are effective drugs for treating type 2 diabetes (T2DM) and have been proven to benefit the heart and kidney. Apart from oral semaglutide, which does not require injection, other peptide GLP-1RAs need to be subcutaneously administered. However, oral semaglutide also faces significant challenges, such as low bioavailability and frequent gastrointestinal discomfort. Thus, it is imperative that advanced oral strategies for peptide GLP-1RAs need to be explored. This review mainly compares the current advantages and disadvantages of various oral delivery strategies for peptide GLP-1RAs in the developmental stage and discusses the latest research progress of peptide GLP-1RAs, providing a useful guide for the development of new oral peptide GLP-1RA drugs.

Efficacy and safety of polyethylene glycol loxenatide in treating mild-to-moderate diabetic kidney disease in type 2 diabetes patients: a randomized, open-label, clinical trial

Objective

This study aimed to evaluate the efficacy and safety of polyethylene glycol loxenatide (PEG-Loxe) compared to those of dapagliflozin in patients with mild-to-moderate diabetic kidney disease (DKD), a prevalent microvascular complication of type 2 diabetes mellitus (T2DM). The study is set against the backdrop of increasing global diabetes incidence and the need for effective DKD management.

Methods

This study constituted a single-center, randomized, open-label, clinical trial. The trial included patients with mild-to-moderate DKD and suboptimal glycemic control. Eligible participants were randomly allocated to one of the two groups for treatment with either PEG-Loxe or dapagliflozin. The primary endpoint was the change in UACR from baseline at 24 weeks.

Results

Overall, 106 patients were randomized and 80 patients completed the study. Following 24 weeks of treatment, the PEG-Loxe group exhibited a mean percent change in baseline UACR of -29.3% (95% confidence interval [CI]: -34.8, -23.7), compared to that of -31.8% in the dapagliflozin group (95% CI: -34.8, -23.7). Both PEG-Loxe and dapagliflozin showed similar efficacy in reducing UACR, with no significant difference between the groups (p = 0.336). The HbA1c levels decreased by -1.30% (95% CI: -1.43, -1.18) in the PEG-Loxe group and by -1.29% (95% CI: -1.42, -1.17) in the dapagliflozin group (p = 0.905). The TG levels decreased by -0.56 mmol/L (95% CI: -0.71, -0.42) in the PEG-Loxe group and -0.33 mmol/L (95% CI: -0.48, -0.19) in the dapagliflozin group (p = 0.023). Differences in TC, HDL-C, LDL-C, SBP, and DBP levels between the groups were not statistically significant (all p > 0.05). Safety profiles were consistent with previous findings, with gastrointestinal adverse events being more common in the PEG-Loxe group.

Conclusions

PEG-Loxe is as effective as dapagliflozin in improving urine protein levels in patients with mild-to-moderate DKD and offers superior benefits in improving lipid profiles. These findings support the use of PEG-Loxe in DKD management, contributing to evidence-based treatment options.

Clinical Trial Registration

www.chictr.org.cn, identifier ChiCTR2300070919.

Glucagon-like peptide-1 analogs: Miracle drugs are blooming?

Glucagon-like peptide-1 (GLP-1), secreted by L cells in the small intestine, assumes a central role in managing type 2 diabetes mellitus (T2DM) and obesity. Its influence on insulin secretion and gastric emptying positions it as a therapeutic linchpin. However, the limited applicability of native GLP-1 stems from its short half-life, primarily due to glomerular filtration and the inactivating effect of dipeptidyl peptidase-IV (DPP-IV). To address this, various structural modification strategies have been developed to extend GLP-1's half-life. Despite the commendable efficacy displayed by current GLP-1 receptor agonists, inherent limitations persist. A paradigm shift emerges with the advent of unimolecular multi-agonists, such as the recently introduced tirzepatide, wherein GLP-1 is ingeniously combined with other gastrointestinal hormones. This novel approach has captured the spotlight within the diabetes and obesity research community. This review summarizes the physiological functions of GLP-1, systematically explores diverse structural modifications, delves into the realm of unimolecular multi-agonists, and provides a nuanced portrayal of the developmental prospects that lie ahead for GLP-1 analogs.

The Discovery and Development of Glucagon-Like Peptide-1 Receptor Agonists

Diabetes mellitus has become a serious life-threatening disease. As one of the new drugs for the treatment of diabetes, GLP-1 receptor agonists have attracted a lot of attention. Compared with traditional hypoglycemic drugs, GLP-1 receptor agonists have good safety and tolerability. To a certain extent, they overcome the problem of the short half-life of natural GLP-1 in vivo and can exist stably in patients for a long time, achieving good results in the treatment of diabetes, as well as improving the symptoms of some complications. The GLP-1 receptor agonists in the market are all peptide drugs. Compared with peptide drugs, small molecule agonists have the advantages of low cost and oral administration. In this article, we review the recent research progress of GLP-1 receptor agonists.

Role of Novel Glucagon-like Peptide-1 Receptor Analogue Polyethylene Glycol Loxenatide in Type 2 Diabetes: A Systematic Review and Meta-analysis

Background

Polyethylene glycol loxenatide (peg-loxenatide) is a novel glucagon-like peptide-1 receptor agonist developed and available for clinical use in China. This meta-analysis was performed as no meta-analysis has analysed the efficacy and safety of peg-loxenatide in type 2 diabetes (T2DM).

Methods

Electronic databases were systematically reviewed for RCTs having patients living with T2DM receiving peg-loxenatide in treatment arm and placebo/any other diabetes medicine in control arm. The primary outcome was to evaluate changes in glycated haemoglobin. The secondary outcomes were to evaluate alterations in weight, blood pressure, fasting glucose, prandial glucose, lipids, and adverse events.

Results

Data from four trials (718 patients) were analysed. Over 12-24 weeks of clinical use, HbA1c was significantly lower in patients receiving standard-dose peg-loxenatide (100 mcg/week) {MD -0.95% [95% confidence interval (CI): -1.19 to -0.71]; P < 0.01; I2 = 76%} and high-dose peg-loxenatide (200 mcg/week) [MD -1.15% (95% CI: -1.47 to -0.82); P < 0.01; I2 = 90%], as compared to placebo. Standard-dose peg-loxenatide was not associated with increased occurrence of nausea [RR 2.87 (95% CI: 0.56 to 14.72); P = 0.21; I2 = 10%], vomiting [RR 4.73 (95% CI: 0.53 to 41.88); P = 0.16; I2 = 0%], and anorexia [RR 0.78 (95% CI: 0.18 to 3.28); P = 0.73; I2 = 0%]. Occurrence of nausea [RR 16.85 (95% CI: 3.89 to 72.92); P < 0.01; I2 = 10%], vomiting [RR 15.90 (95% CI: 2.99 to 84.55); P < 0.01; I2 = 0%], and anorexia [RR 3.85 (95% CI: 1.24 to 11.88); P = 0.02; I2 = 0%] was significantly higher with high-dose peg-loxenatide, as compared to placebo.

Conclusion

Peg-loxenatide (100 mcg/week) is the most appropriate dose for clinical use as it is associated with good glycaemic efficacy with minimal gastro-intestinal side effects.

Thermal stability of exenatide encapsulated in stratified dissolving microneedles during storage

As low-temperature storage and transportation of peptides require high costs, improving the dosage form of peptides can reduce costs. We developed a thermostable and fast-releasing stratified dissolving microneedle (SDMN) system for delivering exenatide (EXT) to patients with type 2 diabetes. Among the tested polymers, dextran and polyvinyl alcohol (PVA) were the best at stabilizing EXT under high-temperature storage for 9 weeks. The two polymers possess a relatively high glass transition temperature (T_g) and weak hydrogen bonding between PVA and EXT. Additionally, zinc sulfate (ZnSO₄) had a stabilizing effect on EXT among the selected stabilizers, suggesting that EXT formed a dimer after coordination with zinc ions (Zn²⁺). In addition, the denaturation temperature (T_m) of EXT was increased by adding ZnSO₄, thus stabilizing EXT. Accordingly, SDMNs consisting of a tip layer (dextran encapsulating the Zn²⁺-EXT complex) and a base layer (PVA) were fabricated. Within 2 min of implantation, the EXT loaded on the patch was quickly released into the skin. Transdermal pharmacokinetics studies showed that manufactured SDMNs generated comparable efficacy to subcutaneous injection. Significantly, the remaining EXT amount was not significantly different under storage at 40 °C and -20 °C for 3 months, supporting that the SDMN system had excellent delivery efficiency and stability, thus reducing the dependence on the cold chain.

GLP-1 receptor agonists for the treatment of obesity: Role as a promising approach

Obesity is a complex disease characterized by excessive fat accumulation which is caused by genetic, environmental and other factors. In recent years, there has been an increase in the morbidity, disability rate,and mortality due to obesity, making it great threat to people's health and lives, and increasing public health care expenses. Evidence from previous studies show that weight loss can significantly reduce the risk of obesity-related complications and chronic diseases. Diet control, moderate exercise, behavior modification programs, bariatric surgery and prescription drug treatment are the major interventions used to help people lose weight. Among them, anti-obesity drugs have high compliance rates and cause noticeable short-term effects in reducing obese levels. However, given the safety or effectiveness concerns of anti-obesity drugs, many of the currently used drugs have limited clinical use. Glucagon-like peptide-1 receptor (GLP-1R) agonists are a group of drugs that targets incretin hormone action, and its receptors are widely distributed in nerves, islets, heart, lung, skin, and other organs. Several animal experiments and clinical trials have demonstrated that GLP-1R agonists are more effective in treating or preventing obesity. Therefore, GLP-1R agonists are promising agents for the treatment of obese individuals. This review describes evidence from previous research on the effects of GLP-1R agonists on obesity. We anticipate that this review will generate data that will help biomedical researchers or clinical workers develop obesity treatments based on GLP-1R agonists.

PEGylated drug delivery systems in the pharmaceutical field: past, present and future perspective

Target-site drug delivery systems are gaining interest in the pharmaceutical field due to their great advantages, such as higher drug dosing capacity and better bioavailability. However, some existing problems need to be overcome. As an example, interaction between blood proteins and drug delivery systems. A potent candidate to approach the mentioned problem is based on polyethylene glycol (PEG) surface modifications. This polymer acts as a protector towards the external possible interactions with other compounds, making targeted delivery possible. Diseases such as cancer, diabetes, haemophilia and pain treatment can benefit from these new systems.This review aims to give an overview of drug delivery systems based on PEGylation as surface modification as pharmaceutical approach. Moreover, a deeper insight of the properties of PEG and its advantages is given, as well as brief overview of present therapies based on this technology.

Polymer-drug conjugates: Design principles, emerging synthetic strategies and clinical overview

Adagen, an enzyme replacement treatment for adenosine deaminase deficiency, was the first protein-polymer conjugate to be approved in early 1990s. Post this regulatory approval, numerous polymeric drugs and polymeric nanoparticles have entered the market as advanced or next-generation polymer-based therapeutics, while many others have currently been tested clinically. The polymer conjugation to therapeutic moiety offers several advantages, like enhanced solubilization of drug, controlled release, reduced immunogenicity, and prolonged circulation. The present review intends to highlight considerations in the design of therapeutically effective polymer-drug conjugates (PDCs), including the choice of linker chemistry. The potential synthetic strategies to formulate PDCs have been discussed along with recent advancements in the different types of PDCs, i.e., polymer-small molecular weight drug conjugates, polymer-protein conjugates, and stimuli-responsive PDCs, which are under clinical/preclinical investigation. Current impediments and regulatory hurdles hindering the clinical translation of PDC into effective therapeutic regimens for the amelioration of disease conditions have been addressed.

Efficacy and safety of polyethylene glycol loxenatide monotherapy in type 2 diabetes patients: A multicentre, randomized, double-blind, placebo-controlled phase 3a clinical trial

AIM

To evaluate the efficacy and safety of polyethylene glycol loxenatide (PEX168) monotherapy in type 2 diabetes (T2D) patients in China.

MATERIALS AND METHODS

In a multicentred, randomized, double-blinded, placebo-controlled phase 3a clinical trial, 361 patients with inadequate glycaemic control (HbA1c 7.0%-10.5%, fasting plasma glucose <13.9 mmol/L) were randomized (1:1:1) for weekly subcutaneous injections: placebo, PEX168/100 μg or PEX168/200 μg. The 24-week treatment was followed by a 28-week extension, during which placebo-treated patients were randomly assigned to PEX168/100 μg or PEX168/200 μg. The primary efficacy endpoint was the HbA1c change from baseline to week 24.

RESULTS

The three groups had similar demographics and baseline characteristics. The HbA1c least-square mean (95% CI) change from baseline to week 24 was greater for PEX168/100 μg (-1.02% [-1.21%, -0.83%]) and PEX168/200 μg (-1.34% [-1.54%, -1.15%]) than for placebo (-0.17% [-0.36%, 0.02%]); (superiority: P < .0001). The proportions of patients with less than 7% HbA1c in the placebo, PEX168/100 μg and PEX168/200 μg groups were 15.7%, 34.7% and 46.6%, respectively. Common gastrointestinal adverse events (AEs) were nausea (5.6%, 10.0% and 0% for PEX168/100 μg, PEX168/200 μg and placebo, respectively) and vomiting (2.4%, 8.3% and 0% for PEX168/100 μg, PEX168/200 μg and placebo, respectively). Six (1.6%) patients (PEX168/100 μg: N = 2 [1.6%], PEX168/200 μg: N = 3 [2.5%] and placebo: N = 1 [0.8%]) discontinued treatment because of AEs. Four (1.2%) patients (PEX168/100 μg: N = 3 [2.5%] and PEX168/200 μg: N = 1 [0.9%]) developed PEX168 antidrug antibodies.

CONCLUSION

PEX168 monotherapy significantly improved glycaemic control in T2D patients with a safety profile resembling that of other glucagon-like peptide-1 receptor agonists.

Polyethylene Glycol Loxenatide (PEX-168) Reduces Body Weight and Blood Glucose in Simple Obese Mice

BACKGROUND

At present, there is a lack of drug treatment for obese patients, so it is needed to find a drug that is effective and has few side effects to treat obesity. PEX-168 is a novel long-acting glucagon-like peptide-1 receptor agonist for T2DM. It improves blood glucose with fewer side effects. The aim of the present study was to investigate the effect of PEX-168 on blood glucose and body weight of mice with simple obesity.

METHODS

Thirty healthy and 6-week-old C57BL/6 male mice were randomly divided into a normal control group (NC, n = 6) and obesity model group (n = 24). The obesity model mice were randomly divided into a high-fat diet group (HF) and intervention groups with different doses of PEX-168 (0.03 mg/kg, 0.1 mg/kg, and 0.3 mg/kg). Each group includes 6 mice. Body weight, food intake, and fasting blood glucose (FBG) were evaluated after intraperitoneal injection, and the intervention was performed weekly for 12 weeks. Fasting insulin (FINS) levels were measured at the 12^th week.

RESULTS

Compared with HF, the food intake of mice in the intervention groups decreased transiently, but there was no difference between different doses (P > 0.05). The body weight of mice in the middle and high dose of PEX-168 intervention groups decreased significantly, and the differences were statistically significant (P < 0.05). The administration of PEX-168 can effectively improve the blood glucose of obese mice, the difference was statistically significant (P < 0.05), but there was no difference between different doses (P > 0.05). At the 10^th week, the incidence of transient hypoglycemia was 67% and 50% in the middle- and high-dose groups, respectively. The levels of serum FINS in the intervention groups were significantly lower than those in the HF group, and the differences were statistically significant (P < 0.05), but there was no difference between different doses (P > 0.05).

CONCLUSIONS

PEX-168 showed significant improvement in the FBG and FINS levels of simple obese mice. Middle and high doses of PEX-168 could reduce the weight of simple obese mice, but there was a certain risk of hypoglycemia.

Polyethylene glycol loxenatide (PEX168) in subjects with renal impairment: A pharmacokinetic study

Aims

Type 2 diabetes mellitus (T2DM) is commonly complicated by renal impairment. Polyethylene glycol loxenatide (PEX168) is a novel long‐acting glucagon‐like peptide‐1 receptor agonist for T2DM. PEX168 pharmacokinetics was studied to identify requirements for dose‐modification in T2DM complicated by renal impairment.

Methods

This was a single‐centre, open‐labelled, parallel‐group, single‐dose, phase I clinical trial of patients with mild and moderate renal impairment, and with or without T2DM. Age‐, sex‐ and body mass index‐matched subjects with normal renal function, and with or without T2DM were recruited as controls. Subjects received a single abdominal subcutaneous injection of PEX168 200 μg. Pharmacokinetic samples were taken at 0, 24, 48, 72, 96, 120, 144, 216, 312, 480, 648 and 720 hours.

Results

Twenty‐three patients were included in the pharmacokinetics analysis. Vz/F and CL/F were lower in the moderate impairment group than in the other groups. The mean t_1/2 (163 hours) in the moderate impairment group was prolonged compared to the mild impairment (117 hours) and normal (121 hours) groups. AUC_0–inf increased by 13 and 100.7% in patients with mild and moderate renal impairment, respectively. Most adverse events were mild gastrointestinal disorders, with only 1 serious adverse event observed.

Conclusion

A single dose of 200 μg of PEX168 was in general well tolerated in patients with renal impairment. The in vivo clearance rate of PEX168 in patients with moderate renal impairment is slower than in patients with mild renal impairment and normal renal function and dose adjustment might be required (http://ClinicalTrials.org #NCT02467790).