Eli Lilly (LLY) stock rose as much as 10% in midday trading on Wednesday after the American drugmaker rolled out a strong sales outlook that touted the strength of its weight-loss portfolio and sent its market cap back near $1 trillion.

The rally in Lilly also pressured shares of its main weight-loss rival, Danish drugmaker Novo Nordisk (NVO), for a second straight day. Novo stock fell as much as 6% in afternoon trade on Wednesday.

Eli Lilly reported Wednesday morning that it expects 2026 revenue to grow sharply, with sales rising between 20% and 25% at the midpoint of its estimates. The company is forecasting revenues of $80 billion-$83 billion, compared to 2025 revenue of $65.2 billion.

Eli Lilly reported fourth quarter revenue of $19.29 billion, exceeding analyst estimates of $17.9 billion. On the bottom line, the company reported adjusted earnings per share (EPS) of $7.54, beating estimates of $6.91.

Danish giant Novo Nordisk has moved in the exact opposite direction, falling by more than 20% over the past five trading sessions and shedding more than $50 billion in market cap as Wall Street digested a far weaker-than-expected outlook.

On Tuesday, Novo Nordisk said it expected a 5%-13% drop in sales for 2026 due to increasing competition and regulation. The company also said its adjusted operating profit growth would fall by 5%-13%, an identical move to its sales.

The company's sales grew by 10% in 2025 as the popularity of its weight-management drugs, Ozempic and Wegovy, exploded; however, the Danish drugmaker has faced greater competition from rivals such as Eli Lilly.

Novo has also faced come-and-go threats from compounded semaglutide makers such as Hims (HIMS), which distributed a generic GLP-1 before the FDA banned the practice in 2025.

Novo's fourth quarter revenue totaled $12.5 billion, topping estimates of $12.1 billion. Adjusted EPS were $0.95 against estimates of $0.91. But the company's earnings and revenue beats weren't enough to outweigh bearish sentiment on its sales outlook.

In its release, Novo attributed the drop in sales to "continued volume penetration from GLP-1 treatments and market expansion, mainly within obesity, as well as intensifying competition and negative impacts from the compound patent expiry of the semaglutide molecule in certain markets" internationally.

Its US sales impact is due to "current prescription trends for the injectable GLP-1 portfolio, intensifying competition as well as negative impact from reduced obesity medication coverage in Medicaid."

Eli Lilly, by contrast, lauded its recent partnership with the US government on expanding access to its obesity medicines, including the Ozempic and Wegovy competitor Zepbound.

"We reached millions more patients — launching Inluriyo, expanding Mounjaro and Kisunla globally, and submitting orforglipron for approval," Eli Lilly CEO David Ricks said in the company's fourth quarter earnings release. "We expanded our manufacturing capacity, and through our US government agreement, opened new access to obesity medicines."

On Novo Nordisk's earnings call on Wednesday, company executives tried to talk up several developments: The company's rare disease unit is "positioned for sustained growth," and its "next-generation" treatments for type 2 diabetes are moving along, CEO Maziar Doustdar said.

In late 2025, Doustdar mentioned, Novo Nordisk received FDA approval for its Wegovy pill, the "first oral GLP-1 for obesity."

Jake Conley is a breaking news reporter covering US equities for Yahoo Finance. Follow him on X at @byjakeconley or email him at jake.conley@yahooinc.com.

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