Eli Lilly presented early clinical data for brenipatide, a once-weekly GIP/GLP-1 receptor agonist candidate, supporting dose selection across substance use, psychiatric, and immunologic disorders. The company shared findings from its Phase I J2S-MC-GZMD trial (NCT06606106) at Psych Congress 2026 in New Orleans, where it evaluated safety, pharmacokinetics, and pharmacodynamics in healthy, overweight, and obese participants. Lilly reported a mean half-life ranging from 9.08 days to 12.5 days, with longer exposure observed at higher doses. The dosing strategy tested 4.5 mg or lower (0.3 mg, 0.75 mg, 1.5 mg, and 3 mg), aligning with Lilly’s plan to test brenipatide’s durability across weekly intervals in neuroscience-focused Phase III programs. The update matters for drug developers pursuing GLP-1–based CNS and inflammation pathways, particularly as brenipatide is designed to target central nervous system and inflammatory circuits tied to reward and addiction biology. Lilly also outlined Phase III trial designs planned to evaluate brenipatide in major depressive disorder and alcohol use disorder. Overall, Lilly’s data reinforces the company’s strategy to extend its incretin platform into complex psychiatric indications while tightening the link between pharmacology and trial execution.