Investors wiped $70 billion off Novo Nordisk's market value on Tuesday after the maker of weight-loss drug Wegovy issued a profit warning and named a new CEO, as it battles rising competition in the obesity drug market.

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Shares in Danish drugmaker Novo Nordisk were down nearly 20% in pre-market trading Tuesday morning after the company cuts its sales and profit estimates.

Novo Nordisk's new CEO Maziar Mike Doustdar has been handed the reins to turn around the Wegovy-making firm's flagging sales growth and sliding share price. He first will need to win over sceptical investors.

The announcement came amid a slump in the company's share price and investor concerns about its experimental drug pipeline and ability to navigate challenges in the US market.

Weight-loss patients voice concerns as CVS Caremark drops Zepbound coverage for Wegovy, though exceptions may exist for those with previous adverse reactions.

The U.S. FDA ban on compounded versions of Novo Nordisk's Wegovy has increased its prescriptions by 33%. Despite this, investor confidence remains shaken due to competitive pressures from Eli Lilly's Zepbound and market challenges.