Novo Nordisk shares rallied on Tuesday as a maker of a weight-loss drug alternative confirmed it won’t be selling it for much longer.

Investors are scrambling to adjust, after the telehealth specialist Hims & Hers said it would stop selling an alternative to Novo Nordisk's Wegovy and Ozempic weight-loss drugs. Hims stock stood about 17% lower at under $42.

After the FDA removed semaglutide injection products from a shortage list, compounders like Hims have 60-90 days to stop making copies.

Hims & Hers said on Monday that it may no longer be able to sell compounded versions of the weight-loss drug made by Novo Nordisk because its pathway to do so closed when the U.S. FDA declared Friday that the drug's shortage was over.

The Food & Drug Administration announced last week that the Ozempic and Wegovy shortage for Novo Nordisk's (NYSE:NVO) was over. It said the Danish pharmaceutical had sufficient supply of its semaglutide therapies to meet current and future,