Adds investor comment in paragraphs 12 and 13, detail on compounding in paragraph 8.

By Stine Jacobsen and Maggie Fick

COPENHAGEN, Feb 9 (Reuters) - Novo Nordisk sued Hims and Hers Health HIMS.N on Monday over patent infringement after the U.S. telehealth firm launched, then cancelled, a $49 copy of Novo's weight-loss pill Wegovy following backlash from the U.S. Food and Drug Administration.

Novo's shares NOVOb.CO jumped nearly 7% on Monday, while Hims sank 20% in early trading. Shares of Novo and rival Eli Lilly LLY.N had tumbled last week after Hims introduced the cut-price pill, which had looked set to erode Novo's takings and jeopardise its shift towards a cash-pay consumer market.

The lawsuit and tough FDA response could mark a broader crackdown on compounded GLP-1 drugs mixed by pharmacies that have dented the profits of Novo and Lilly, analysts said, reducing competition on the big manufacturers' patented weight-loss treatments.

'WAR ON GLP-1 COMPOUNDERS IN GENERAL'

Sydbank analyst Soren Lontoft Hansen said the FDA's swift response was positive for Novo Nordisk and rival Lilly's branded obesity drugs.

"They are not only declaring war on Hims & Hers' Wegovy pill, but GLP-1 (compounders) in general," he said.

Novo said in a statement it was "asking the court to permanently ban Hims from selling unapproved, compounded drugs that infringe our patents, and is seeking to recover damages."

U.S. regulations have allowed compounding pharmacies to manufacture and sell brand-name medicines if they are in short supply by mixing drug ingredients. Without a shortage, compounding is only allowed in the U.S. when the drug is personalized for a patient, such as at doses not available in the branded medicines.

HIMS' SHARES TUMBLE IN PREMARKET

Hims, whose pill was based on semaglutide - used in Novo Nordisk's blockbuster drugs Wegovy and Ozempic - had said on Saturday it would stop offering the treatment.

Shares of Hims sank 20% in premarket trading, deepening earlier declines. Lilly's shares, already near record highs, were up 2% in premarket trading.

"I think the FDA made it quite clear that they would not tolerate a compounded Wegovy pill. This was an attack on the authority of the FDA," said Novo and Lilly shareholder Markus Manns about Hims' $49 pill.

"I wonder if this backfires to Hims and the FDA becomes also tougher on compounded semaglutide injections."

RARE VICTORY FOR NOVO AS IT FIGHTS COMPOUNDED DRUGS

The FDA said on Friday it would restrict GLP-1 ingredients used in non-approved compounded drugs that Hims and other compounding pharmacies have marketed as alternatives to authorized treatments.

Jyske Bank analyst Henrik Hallengreen Laustsen said Novo's share jump reflected investors' positive response to the FDA's clampdown on unregulated drug compounding.

"This may lead some to speculate about what will happen to these compound injections. Will there be increased pressure on them, and will they also be pushed out of the market more than just the pills?"

Hims' swift reversal of its pill launch marked a rare victory in Novo Nordisk's battle against copycat compounded versions of its GLP-1 drugs.

Hims did not respond to Reuters' requests for comment on Saturday.

PRICING PRESSURES REMAIN FOR NOVO NORDISK

Novo's shares had already rebounded over 5% on Friday after the FDA signalled its crackdown on compounded GLP-1 medications.

Still, intense competition continues in the rapidly shifting GLP-1 market as Eli Lilly and compounding pharmacies offer injectable versions of semaglutide.

Novo Nordisk's market value has dropped nearly two-thirds since it peaked in June 2024 and is down nearly 50% over the past year. Its stock sank 17% in a day last week after it flagged "unprecedented price pressure."

Despite pioneering the obesity drug market, the recent setbacks show how quickly Novo's dominance has eroded. And with Eli Lilly's oral GLP-1 pill orforglipron expected to launch in April, competitive pressure is set to intensify.

In the key U.S. market, the obesity drugs made by Novo Nordisk and Lilly are driving a shift to a consumer-focused market in which drugmakers are increasingly looking to cash-pay channels and telehealth to reach tens of millions of Americans.