Eli Lilly fell after new forecasts showed sales of the weight-loss drug were growing faster than expected.

Shares of Eli Lilly ( LLI ) fell more than 6 percent on Tuesday.

Lilly lowered its revenue guidance by 5 percent to $13.5 billion, missing the $14 billion consensus by $500 million. But guidance still represents a 45% increase from the same quarter in 2023. Lilly previously gave a range of $13.9 billion to $14.5 billion. The company issued full-year 2024 guidance of $45 billion, or 32% more than 2023 guidance.

“While the US incretin (hormones that help control postprandial blood sugar) market grew 45% compared to the same quarter last year, our previous guidance for the quarter expected faster growth. That, in addition to lower-than-expected year-end channel inventory, contributed to our Q4 results. We continue to make improvements in our manufacturing results, and US supply of all tirzepatide Q4,” Lilly CEO David Ricks said in a statement.

The move in the market surprised some experts and analysts as the market had expected a somewhat softer Q4.

“Despite this disappointing second quarter result, we expect 2025+ financial performance and pipeline news flow (especially oral GLP-1 orforglipron Ph3 results) to be encouraging,” Leerink Partners analyst David Reisinger said in a note to clients.

JPMorgan analyst Chris Schott agreed. “Overall, while 4Q dynamics represent a squeeze on the story, we expect the story’s focus to shift to RXs’ continued climb, newly released 2025 guidance, as well as several upcoming triggers.”

Lilly expects its most popular blockbuster products — GLP-1 tirzepatide products Mounjaro and Zepbound — to lose traction as well.

Guidance for diabetes drug Mounjaro is $3.5 billion, while weight loss drug Zipbord is expected to bring in $1.9 billion in the quarter.

According to JPMorgan’s latest weekly prescription tracking data from pharmaceutical information firm IQVIA, Zepbound’s year-over-year weekly prescription average increased 241% in the quarter, while Mounjaro’s increased 51%.

Anjali Kemlani He is a senior health reporter at Yahoo Finance, covering all things pharma, insurance, managed care, digital health, PBMs, and health policy and politics. It certainly includes GLP-1s. Follow Angela on social media platforms X, LinkedIn and Bluesky @AnjKhem.

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