Novo Nordisk unveiled its latest data for a weight-loss drug candidate, but shares of the maker of Wegovy and Ozempic tumbled as the results missed investors’ expectations and reignited concerns about Novo’s rivalry with Eli Lilly.

Novo Nordisk’s new weight-loss drug helped patients lose even more weight on average than its current Wegovy blockbuster treatment, an early-stage trial showed, as the drugmaker races to develop the next generation of obesity medicines.

Ahead of the launch, the firm has taken steps to amplify its production capacities to ensure adequate supply, and believes that its position as a market leader for insulin products in the country could give it an edge.