Metsera, the US biotech with a pipeline of next-generation metabolic hormone weight loss drugs, has agreed a sale to Pfizer following a bidding war between the US pharma giant and Novo Nordisk.

On 22 September, Metsera had agreed a deal in which Pfizer would pay just under $5 billion (£3.7 billion) up front, plus over $2 billion in additional payments based on performance milestones for Metsera’s drug pipeline. However, before the deal closed Novo Nordisk interjected with a higher offer, sparking a bidding war that involved Pfizer also filing two lawsuits to try and block Metsera from accepting Novo’s offer – including one suggesting Novo’s intention was to suppress competition with its existing weight loss drugs.

On 7 November, Metsera decided to accept a revised deal from Pfizer, worth over $7 billion up front, and a slightly reduced performance-related element that could still just top the $2 billion mark. Pfizer’s offer matched Novo’s in terms of value, and had the advantage of ready approval from the US Federal Trade Commission (FTC). By contrast, Novo’s proposal involved more risk, since the FTC had warned Metsera of its concerns over the deal’s slightly unusual payment structure. Novo has said it will not further raise its offer.