(Bloomberg) -- Shortages of Eli Lilly & Co.’s Mounjaro have expanded to include all of the higher doses, showing just how strong demand is for the drug before it even gets formal approval for use in obesity.

Just last month, US regulators said that three of the higher doses of Lilly’s drug were experiencing “intermittent backorders” through July due to increased demand. The latest update adds a fourth dose to that list and extends issues with another, higher-dose option through September, according to a Food and Drug Administration website. Only the two lowest doses of the drug remain fully available.

A spokesperson for Eli Lilly confirmed that the updates to the FDA’s website reflect the current situation for Mounjaro and that the company continues to be in regular contact with the agency. Lilly has also said it’s investing in expanding manufacturing capacity.

Mounjaro, also known as tirzepatide, was approved in the US last year to help patients with type 2 diabetes control their blood sugar levels. Lilly is seeking FDA approval for Mounjaro as an obesity treatment: In trials, higher doses of the drug helped patients lose as much as 50 pounds. Lilly is also studying other drug combinations in search of even higher levels of weight loss. 

The drugmaker recently acquired obesity drug startup Versanis Bio for as much as $2 billion, further extending its reach in the weight-loss market.

Lilly’s shortage comes amid a separate one reported last week of an older, less effective weight-loss treatment made by Novo Nordisk A/S called Saxenda. The company said it’s still making and shipping Saxenda, but warned of issues filling prescriptions for “the remainder of 2023 and beyond.” Novo’s other drugs in this class, Ozempic and Wegovy, have also faced supply snags as demand skyrockets.

Prescriptions of these kinds of weight-loss drugs this year are on track to outpace 2022, according to the health-care technology company Komodo Health Inc. While only Wegovy and Saxenda are actually approved for weight management, these types of drugs are increasingly being given to patients as an obesity treatment despite formal approval, a process known as “off-label” prescribing. 

The global obesity market is likely to reach $77 billion by 2030, according to a research note from Morgan Stanley, more than $20 billion higher than the firm’s initial projections. The analysts also expect Novo and Lilly to remain leaders in the space, even with increased competition, with a combined 82% share of the obesity market long-term.

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