PatientSafe Solutions, a US-based hospital safety company backed by local drugs group Merck’s corporate venturing unit, has raised $20m in its series C round.

Last month, PatientSafe said it had raised $13m, according to an updated filing with the Securities and Exchange Commission.

Merck’s Global Health Innovation (GHI) fund led the C round and was joined by existing venture investors, including Camden Partners, TPG Capital, and Psilos Group.

Maxwell Kahn, an investment principal at Merck GHI, has joined PatientSafe’s…