A randomized phase I study of BI 1820237, a novel neuropeptide Y receptor type 2 agonist, alone or in combination with low-dose liraglutide in otherwise healthy men with overweight or obesity.

Aims: Pharmacotherapeutic options for obesity treatment include glucagon-like peptide-1 receptor (GLP-1R) agonists, for example, liraglutide. However, an unmet need remains, particularly in patients with a high body mass index (BMI), as GLP-1R agonists are associated with gastrointestinal adverse events (AEs) and some patients do not respond to treatment. Neuropeptide Y (NPY) and peptide YY bind G-protein-coupled Y receptors and represent attractive targets for modulating bodyweight.

Materials and methods: This first-in-human, three-part, partially blinded phase I study (NCT04903509) investigated the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of single ascending doses of the peptidic NPY2R agonist BI 1820237, with/without low-dose liraglutide: part 1 (participants randomized to receive BI 1820237: 0.075-2.4 mg or placebo), part 2 (BI 1820237: 1.2 mg or placebo) and part 3 (BI 1820237: 0.025-1.2 mg + liraglutide 0.6 mg or placebo + liraglutide 0.6 mg). Primary endpoint is the proportion of participants with drug-related AEs. Secondary endpoints are tolerability, PK and PD.

Results: In total, 95 otherwise healthy men with increased BMI (25.0-34.9 kg/m²) were randomized. Drug-related AEs, mainly gastrointestinal events, were reported by 39.0% of participants (n = 23) in parts 1 + 2 and 30.6% of participants (n = 11) in part 3; one drug-related AE (11.1%, part 3) was reported in a participant receiving placebo with liraglutide. Post-dose paracetamol PK suggested that BI 1820237 and low-dose liraglutide exhibited additive effects on gastric emptying.

Conclusions: BI 1820237 treatment was associated with transient nausea and vomiting at higher doses. No differences in tolerability were observed when combined with liraglutide; effects on gastric emptying appeared additive.