Novo Nordisk A/S shares slid Thursday after the Danish drugmaker reported quarterly earnings that missed analyst estimates and lowered its full-year outlook, fueling investor anxiety over slowing growth in its blockbuster obesity franchise.

The company posted third-quarter earnings of 4.50 kroner per share, falling short of analysts’ expectations of 4.90 kroner, according to data compiled by FactSet. Novo also trimmed its annual sales guidance, citing moderating demand for Wegovy, its weight-loss injection that has driven the company’s meteoric rise over the past two years.

The softer outlook comes as Eli Lilly & Co. intensifies competition in the obesity drug market with its rival treatment Zepbound, which has quickly gained traction in the U.S. Novo’s dominance in the fast-growing sector is also being tested by supply constraints and increasing pricing scrutiny from regulators and insurers.

Adding to market unease, Novo is undergoing a period of transition marked by executive changes and planned layoffs, part of a broader restructuring to refocus resources on obesity and diabetes treatments.

In a sign of its continued ambition in the space, the company recently entered a bidding war with Pfizer Inc. for Metsera, a privately held biotech specializing in obesity therapies. Novo’s Chief Financial Officer defended the offer—both in value and structure—amid legal challenges from Pfizer, which has accused Novo of anticompetitive behavior.

Despite investor concerns, Novo executives said the revised guidance reflects a “prudent recalibration” of expectations as the company invests heavily in capacity expansion and next-generation obesity drugs.

Shares of Novo Nordisk were down in Copenhagen trading, extending a recent pullback that has erased part of the company’s market-value gains from earlier this year.

The moves underscore the increasingly competitive landscape for obesity and diabetes treatments—markets once dominated by Novo but now drawing deep-pocketed rivals and heightened regulatory scrutiny.