| Name of Subsidiary | Jurisdiction of incorporation or organization | |||||||
| Summit Therapeutics Sub Inc. | Delaware, USA | |||||||
| Summit International Holdings Limited (Cayman Islands) | Cayman Islands | |||||||
| Summit Therapeutics Global LLC | Delaware, USA | |||||||
| Summit (Oxford) Limited | England and Wales | |||||||
| Summit Therapeutics Limited | England and Wales | |||||||
| Discuva Limited | England and Wales | |||||||
| Summit Therapeutics Swiss STS GmbH | Switzerland | |||||||
| Summit Therapeutics Ireland Limited | Ireland | |||||||