Eli Lilly’s planned Biologics License Application submission for retatrutide in Q1 2027 forms the core driver behind the market’s 95% implied probability of no FDA approval in 2026. The triple agonist remains investigational, with multiple phase 3 TRIUMPH and TRANSCEND trials delivering positive weight-loss and glycemic data but no marketing application yet filed. FDA review timelines—typically 10 months under standard review after the 60-day filing period—place any potential decision well into 2027 or later, even with priority review. Recent classification disputes over whether retatrutide qualifies as a drug or biologic add procedural uncertainty without accelerating the 2026 window. A surprise early filing or unprecedented expedited review could theoretically shift odds, though current official statements and trial completion status make that outcome improbable.