The lung treatment developer could be bought from backers including Merck and Novo for up to $444m.

New York-listed healthcare company Bristol-Myers Squibb (BMS) has signed an exclusive option to acquire Sweden-based Galecto Biotech for up to $444m from its investors, which include pharmaceutical company Merck Serono.

As part of the option, BMS gains global rights to its lead asset, TD139, which could treat lung problems called idiopathic pulmonary fibrosis.

Galecto Biotech had raised more than SEK 40m ($4m) from MS Ventures, which is owned by Merck Serono, Novo Seeds, the seed-stage corporate venturing unit of pharmaceutical…