Jan 9 (Reuters) - British drugmaker GSK on Tuesday said it would acquire Aiolos Bio for a $1 billion upfront payment and up to $400 million in certain success-based regulatory milestone payments.

The acquisition will help beef up GSK's respiratory diseases portfolio, which is currently growing on the back of its respiratory syncytial virus (RSV) vaccine's strong launch.

Founded in 2023, Aiolos is developing a drug ready to enter late stage trials for the treatment of adult patients with asthma.

(Reporting by Eva Mathews in Bengaluru; Editing by Rashmi Aich)