Bofanglutide

GZR18, a novel long‐acting GLP‐1 receptor agonist, has demonstrated substantial metabolic improvements in diabetic and obese animal models. The present studies aimed to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of the ascending dose of GZR18 in healthy American and Chinese subjects.

In these phases 1, randomized, double‐blind, placebo‐controlled, sequential, dose‐escalation US and Chinese studies, healthy American and Chinese adults with similar age were enrolled to once‐weekly subcutaneous injection of GZR18 or placebo. The studies included three cohorts of male American subjects (cohorts US‐1–3) and six cohorts of Chinese subjects (cohorts CN‐1–6, male and female), each with a specified target dose of GZR18 ranging from 1 to 50 μg/kg (1–10 μg/kg for US study and 5–50 μg/kg for Chinese study). The primary endpoints were the safety and tolerability of GZR18. Blood samples were collected for PK and PD analysis of GZR18 before and after dosing. A population PK analysis of GZR18 was conducted to ascertain whether there are ethnic PK differences between American and Chinese adults.

The exposure of GZR18 was comparable between healthy American and Chinese subjects, with the geometric mean ratio between the two populations for AUC 0‐t and Cmax close to 1. A dose‐dependent increase in AUC 0–t and Cmax occurred in both populations. The median time to maximum plasma concentrations ( Tmax ) in American subjects ranged from 72 to 96 h, and the mean Tmax ranged from 60 to 72 h in Chinese subjects. The half‐life of GZR18 was approximately 7 days in both American and Chinese subjects. Evident body weight reduction was observed in GZR18 treatment groups in Chinese subjects (cohorts CN‐3–6 on Day 15, −1.25 to −1.86 kg; −1.88% to −3.11%). No deaths, serious adverse events or hypoglycaemia were reported. Decreased appetite and nausea were the most frequently reported treatment‐emergent adverse events, observed in Chinese study and mild in severity. The safety profile of GZR18 was generally consistent with the same class of drugs.

GZR18 demonstrates good tolerability in healthy American and Chinese subjects. No ethnic differences were observed between healthy American and Chinese subjects. The safety, PK and PD profiles of GZR18 support its further clinical evaluation for glycaemic and body weight control.

GZR18 is a novel analog of glucagon-like peptide-1 (GLP-1). This study evaluates the pharmacology, pharmacokinetics, and efficacy of GZR18, and its potential for the treatment of Type 2 diabetes mellitus (T2DM). In vitro pharmacology and activity of GZR18 were characterized by a binding assay of GZR18 using human serum albumin (HSA), an activation assay in human GLP-1 receptor-expressing cell lines, and its effect on glucose-stimulated insulin secretion (GSIS) in primary mice islets. Pharmacokinetic profiling was performed in Sprague Dawley rats and cynomolgus monkeys, and efficacy evaluated using GZR18 single or repeated doses in db/db mice. GZR18 showed similar binding affinity for HSA and GLP-1 receptor compared with semaglutide and liraglutide. GZR18 increased GSIS, which was confirmed by dynamic islet perifusion and fluorescence imaging using PKZnR-5 for real-time detection. In cynomolgus monkeys, the average GZR18 maximal concentration was 527 nmol L^-1, the terminal half-life (T_1/2) was 61.3 h, and the time to maximum concentration was 14 h. Single-dose GZR18 lowered blood glucose levels and reduced body weight over 72 h in db/db mice. GZR18 successive administration (every three days for 33 days, i.e. 11 doses) lowered nonfasting and fasting blood glucose levels (p < 0.05 versus control) and glycated hemoglobin, following the 11th dose. Food and water consumption in db/db mice was lowered following repeated doses of GZR18 (p < 0.05 versus control), without a reduction in body weight. These results demonstrate the potential of GZR18 as a long-acting GLP-1 analog for the treatment of T2DM.