The Marlboro-maker will pay 150 pence per share in cash, valuing Vectura at £1 billion (US$1.4 billion), the pair said in a statement.

The deal trumped a £958-million bid from private equity firm Carlyle that was agreed in May.

Philip Morris said today’s move was part of its expansion “beyond tobacco and nicotine” and into “a broader healthcare and wellness company”.

The group had in February identified respiratory drug delivery as a key focus, under broader plans to generate at least US$1 billion in annual net revenues from nicotine-free products by 2025.

Since 2008, the cigarette giant has invested more than US$8 billion in smoke-free products, “with the aim of disrupting its own traditional business”, the statement added.

The US group wants to concentrate more on smoke-free products like vaping “that are less harmful than smoking”, it said.

AJ Bell investment director Russ Mould said “there seems to be an element of poacher turned gamekeeper for Philip Morris”.

He added: “Vectura shareholders may be pleased this is an all-cash offer, as many might have had objections to being left with a position in a manufacturer of harmful cigarettes as opposed to a business working to improve people’s health”.