MUMBAI/NEW DELHI, March 25 -- As semaglutide, the drug behind weight-loss drug Ozempic, goes off-patent in India and cheaper copies flood the market, Novo Nordisk has moved to defend its flagship brand, kicking off a fresh legal battle with Dr. Reddy's Laboratories over a rival name it says is too close for comfort.

The Danish drugmaker has approached the Delhi High Court to block Dr. Reddy's from launching a generic version of semaglutide under the brand name "Olymviq", arguing that it is phonetically and structurally similar to Ozempic and risks confusing patients and prescribers.

Hearing the matter on Wednesday, justice Jyoti Singh directed Dr. Reddy's to halt the rollout of the brand, directly and indirectly, including manufacture, ...