Sanofi expanded its relationship with AI-driven biologics developer Earendil Labs through a new agreement worth up to $160 million in near-term checks, adding to a prior Sanofi–Earendil pact that could total $2.56 billion. Under the latest deal Sanofi will develop and commercialize bispecific candidates discovered by Earendil; Earendil retains certain development economics and tiered royalties. Earendil positions itself as an AI-native protein-design shop; Sanofi’s repeat investments indicate Big Pharma’s strategy of buying optionality on algorithmic discovery platforms rather than building in-house alternatives. The deals cover autoimmune and inflammatory targets and include upstream discovery, experimental validation and downstream commercialization rights. For biotech investors and partnering teams, the transactions reinforce an active market for platform-enabled small companies that can generate multiple program exits via staged deals. The near-term test will be whether AI-first candidates progress into IND-enabling studies with conventional preclinical packages.