Biopharma's six biggest crossover rounds ever, led by Kailera's $600 million Series B
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BioSpace and PitchBook have compiled the six largest crossover financings in biopharma history, spanning rounds raised by companies transitioning from private to public backing ahead of IPOs. Kailera Therapeutics' $600 million Series B tops the list. Three of the six largest rounds closed in 2025, a year in which crossover financing across biopharma totaled $3.83 billion. The compilation highlights how late-stage private investors are continuing to place large bets on clinical-stage drug developers. The full ranking, and the context around each deal, is laid out in the report.
Written by a model from the reports · updated 2 hours ago
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- BioSpacePickThe 6 biggest crossover rounds in biopharma history
BioSpace, together with PitchBook, reviews the six largest crossover rounds in biopharma history. 2025 contributed three of them, and the year's crossover total reached $3.83 billion.
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