Eli Lilly’s stock was set to suffer its worst day in four years after sales of diabetes and obesity drugs Mounjaro and Zepbound missed expectations.

Shares of Eli Lilly were taking a 6.9% hit toward a two-month low in recent trading, enough to make them the S&P 500's biggest decliner. The problem is that the drug giant provided fourth-quarter revenue guidance that was below Wall Street expectations,

Heading into fiscal 2025, CEO David Ricks said the company expects sales of weight-loss drugs will continue growing, and noted that it expects "to produce at least 60% more salable doses" of the drugs over the first half of this year compared to 2024.

Eli Lilly shares fell after the drugmaker warned that sales of its hot diabetes and anti-obesity drugs are growing more slowly than expected. Lilly now expects fourth-quarter sales of $3.5 billion for diabetes drug Mounjaro and $1.