Cardiovascular safety of orforglipron versus insulin glargine in adults with type 2 diabetes at increased cardiovascular risk (ACHIEVE-4): a phase 3, event-driven, randomised, open-label, non-inferiority, active comparator trial

BACKGROUND Orforglipron is an oral, non-peptide GLP-1 receptor agonist. While some peptide GLP-1 receptor agonists have established cardiovascular benefit, the cardiovascular safety of non-peptide GLP-1 receptor agonists has not been studied. This study aimed to compare the effect of orforglipron with insulin glargine on the incidence of major adverse cardiovascular events in individuals with type 2 diabetes and obesity or overweight who are at increased risk for cardiovascular events. METHODS This event-driven, phase 3, multicentre, randomised, open-label, active comparator, parallel-group study was conducted in 317 sites across 16 countries and territories. Adults with type 2 diabetes at increased cardiovascular risk with glycated haemoglobin (HbA1c) concentrations between 7·0% and 10·5% (53-91 mmol/mol) and a BMI of 25 kg/m2 or more, treated with up to three glucose-lowering medications (metformin, a sulfonylurea, and/or an SGLT2 inhibitor), were randomly assigned (1:1) to oral orforglipron maximum tolerated dose (up to 36 mg capsule [equivalent to 17·2 mg tablet]) or injectable titrated insulin glargine, each administered once daily. All participants had established cardiovascular or chronic kidney disease. The primary outcome was time to occurrence of four-component major adverse cardiovascular events (MACE-4), including cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, or hospitalisation for unstable angina. Non-inferiority of orforglipron to insulin glargine was declared if the upper limit of the two-sided 95% CI for the hazard ratio (HR; orforglipron vs insulin glargine) was less than 1·8. The primary endpoint and other safety endpoints were assessed in all participants who took at least one dose of assigned treatment using all datapoints from baseline until withdrawal or study completion, regardless of treatment adherence. This trial was registered on ClinicalTrials.gov (NCT05803421) and is completed. FINDINGS Between May 1, 2023, and Sept 5, 2024, 2749 participants were randomly assigned (1371 to orforglipron and 1378 to insulin glargine). 1032 (38%) participants were female and 1717 (62·5%) male. 2362 (85·9%) participants had established cardiovascular disease and 1033 (37·6%) had chronic kidney disease. Mean baseline age, HbA1c, and BMI were 63·1 years (SD 9·9), 8·2% (1·0), and 33 kg/m2 (6·2), respectively. Over a median follow-up of 2 years, the primary outcome occurred in 57 (4·2%) of 1358 orforglipron participants and 67 (5·0%) of 1343 insulin glargine participants, showing non-inferiority to insulin glargine for MACE-4 (HR 0·84; 95% CI 0·59-1·20; p<0·0001 for non-inferiority). Gastrointestinal adverse events were reported in 851 (62·1%) of 1371 orforglipron participants and 193 (14·2%) of 1355 insulin glargine participants; clinically significant or severe hypoglycaemia (glucose <3 mmol/L [54 mg/dL]) occurred in 93 (6·8%) of 1371 orforglipron participants and 260 (19·2%) of 1355 insulin glargine participants. 62 deaths were reported during the study: 19 (1·4%) of 1371 participants receiving orforglipron and 43 (3·2%) of 1355 participants receiving insulin glargine; all deaths except one (in the insulin glargine group) were deemed unrelated to treatment. INTERPRETATION In people with type 2 diabetes at increased cardiovascular risk, the cardiovascular safety of orforglipron was confirmed by demonstrating non-inferiority to insulin glargine for MACE-4. Gastrointestinal adverse events were the most frequent adverse event and most common reason for orforglipron treatment discontinuation with orforglipron, while clinically significant hypoglycaemia occurred less frequently with orforglipron than with insulin glargine. These findings support orforglipron as a potential once-daily, oral treatment option with established cardiovascular safety in people with type 2 diabetes and increased cardiovascular risk.