Novo Nordisk abruptly ended its partnership with Hims & Hers after the Danish drugmaker accused the telehealth company of illegally selling cheaper copycats of Novo Nordisk’s weight-loss drug and engaging in deceptive marketing.

Novo Nordisk said it's ending its collaboration due to concerns with Hims & Hers the company's sales and promotion of cheap knock-offs of the weight loss drug Wegovy, it said on Monday.

Hims & Hers (HIMS) stock plummeted around 30% in early trading Monday after Novo Nordisk (NVO) announced it was ending a collaboration to make its blockbuster weight-loss drug, Wegovy, available on Hims' telehealth platform.