Shares in Forma Therapeutics Holdings Inc. gained 51% as Novo Nordisk A/S made a $20-per-share offer that values the firm’s equity at $1.1 billion. The stock (NASDA:FMTX) had closed at $13.40 prior to the disclosure of the bid on Sept. 1. It closed the day at $20.24, up $6.84, suggesting at least some optimistic investors believe the final price could go higher.