Nasdaq-listed Exscientia shares crashed by more than a fifth as the Oxford-based biotech fired its founder and chief executive over "inappropriate relationships" with two employees.
In a statement, the AI-focused drug developer said that Andrew Hopkins's behaviour was inconsistent with “the company’s standards and values”.
Hopkins has been removed from his role on the board effective immediately, with a special committee established and an outside counsel appointed to look into his behaviour.
Chairman David Nicholson resigned from the board two days ago after it was discovered he knew about one of Hopkins' relationships.
Exscientia added that the termination of Hopkin’s contract had nothing to do with operational or financial performance.
Dave Hallett, chief scientific officer, has been promoted to interim chief executive with Elizabeth Crain now interim chairman.
Shares in Exscientia were expected to rally around 5% when US markets open, having closed at US$5.80, valuing the company at US$720 million.