Rigontec, a Germany-based RNA therapeutics developer backed by pharmaceutical firm Boehringer Ingelheim, yesterday agreed to an acquisition by US-based pharmaceutical company Merck for up to €464m ($554m).

Merck, through an unnamed subsidiary, will make an upfront cash payment of €115m, with the remaining €349m dependent on clinical, development, regulatory and commercial milestones. The deal is subject to certain closing conditions.

Rigontec, spun out from University of Bonn’s Institute for Clinical Chemistry and Clinical Pharmacology in 2014, is developing an immuno-oncology…