Pfizer (NYSE:PFE) just pulled the plug on its daily weight-loss pill, danuglipron, after a clinical trial flagged a potential drug-related liver injury. That decision comes after earlier setbacks tied to severe nausea in its twice-daily versionand leaves Pfizer even further behind in a weight-loss market expected to hit $130 billion by 2030. With demand for Covid products fading fast, the company had pinned big hopes on obesity drugs to fill the gap. Instead, it's now heading back to the drawing board.

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The market didn't take the news lightly. Pfizer shares dropped around 1% premarket 8.59am, while rivals popped. Novo Nordisk (NYSE:NVO) jumped 2.75%, Eli Lilly (NYSE:LLY) rose 2.27% , and Viking Therapeutics (NASDAQ:VKTX) soared nearly 20% in the premarket trading at the same timeall riding momentum from stronger weight-loss offerings. Lilly's Zepbound, a once-weekly injectable, is already generating nearly $5 billion a year and has an oral version in the final stretch of trials. Structure Therapeutics and AstraZeneca aren't far behind, with their own oral contenders in the pipeline.

This misstep throws more heat on Pfizer CEO Albert Bourla, who's under pressure to offset looming patent cliffs that could wipe out $15 billion in revenue by decade's end. So far, the pipeline hasn't delivered, and the M&A spree hasn't produced a clear winner. As competitors rack up approvals and market share, Pfizer may have to rethink its next moveand fast. Investors will be watching closely to see if another round of strategic acquisitions is in the cards.