Meanwhile, Eli Lilly's Zepbound injection has gained traction, prompting both firms to race toward more convenient weight?loss pills. Investors will watch upcoming trial readouts and regulatory decisions closely.

Eli Lilly and Company's Zepbound demonstrated superior weight reduction compared to Novo Nordisk's Wegovy in a 72-week head-to-head trial.

The momentum is now with Lilly. Visible Alpha, a data firm, expects its sales of obesity drugs to overtake Novo’s by 2027 (see chart 2). Lilly’s edge rests on a more effective drug, better execution, keener pricing and a stronger pipeline.