PHARMACEUTICAL majors AstraZeneca and Sanofi have agreed to swap 210,000 compounds from their proprietary libraries as part of efforts to encourage open innovation in drug development. No money will change hands between the two companies, in what is a relatively new collaborative approach. Both companies will be able to increase the diversity of their compound libraries. AstraZeneca and Sanofi have chosen compounds from each others’ libraries which plug gaps in their own, and will share chemical structures and the procedures to make them.