Roche has acquired rights to an obesity therapy by Denmark's Zealand Pharma in a collaboration deal worth up to $5.3 billion, as the Swiss drugmaker seeks to boost its prospects in the booming weight-loss market.

Swiss pharmaceutical giant Roche said Wednesday that it had struck a deal worth up to $5.3 billion to develop Zealand Pharma's obesity drug candidate.

Roche has parted with $1.4 billion upfront to secure rights to an obesity candidate developed by Zealand Pharma, taking its tally of weight-loss candidates in clinical development to five.