Padlock Therapeutics

Padlock Therapeutics was a private biotechnology company focused on discovering small-molecule therapies for autoimmune diseases by inhibiting protein-arginine deiminase (PAD) enzymes involved in protein citrullination. The company was founded in 2014 based on scientific work from Kerri Mowen and Paul Thompson and built a platform around biological and structural insights into the PAD enzyme family. Its lead efforts were centered on PAD4-selective allosteric inhibitors, with systemic lupus erythematosus highlighted as an initial development focus and broader applicability discussed in autoimmune diseases such as rheumatoid arthritis. Padlock raised a $23 million Series A financing and was acquired by Bristol-Myers Squibb in 2016 in a deal valued at up to $600 million. Following the acquisition, Padlock ceased to operate as an independent company.