(Bloomberg) -- Nearly all doses of Eli Lilly & Co.’s weight-loss drug Zepbound will now be in shortage through at least the beginning of summer as demand for the blockbuster injections continues to surge.

Only the lowest dose of Zepbound, a 2.5 milligram shot normally used for the first month of treatment, is listed as “available” through the first half of the year, according to the US Food and Drug Administration website. The agency had earlier said just two of six doses would be in limited supply through the end of April.

“We recognize this situation may cause a disruption in peoples’ treatment regimens and are working with purpose and urgency to help meet the surge in demand,” Lilly said in an emailed statement. 

Dozens of patients from across the US have told Bloomberg in recent weeks that they were unable to get the medication at local pharmacies or through online platforms like Amazon Pharmacy or LillyDirect. 


Lilly shares rose as much as 3.4% Wednesday after the company released study results showing that Zepbound helped patients with sleep apnea, a potential new use for the drug. The stock pared more than half those gains after Bloomberg reported the expanded shortages. 

Pre-Filled Pens

Part of Lilly’s problem is producing the pre-filled pens that patients use to inject the drugs. Making them requires some of the most complex production systems “on the planet,” Chief Executive Officer David Ricks said in August. 

Read More: Zepbound Pen Shortage Has Patients Clamoring for Vials of Drug

Some patients have called for Lilly to release single-dose vials of Zepbound and its diabetes drug Mounjaro to boost supply while the company works to ramp up injector production. The FDA also said shortages of almost all doses of Mounjaro would last through the middle of the year. 

Doctors will still prescribe the 2.5 milligram dose, even if it can’t be increased due to shortages, said Katherine Saunders, the co-founder of Intellihealth, a private telehealth company specializing in obesity care. 

“Even a dose of 2.5 mg is associated with clinically significant weight loss for many people, especially if we combine Zepbound with other anti-obesity medications,” she said in an email. It was unlikely that insurers would cover double doses of the drug, she said. 

Lilly and rival Novo Nordisk A/S are locked in a battle to dominate sales of the anti-obesity drug market, with both working to boost output. Four of five doses of Novo’s Wegovy are in shortage, according to the FDA. Novo Nordisk has made plans to pay $11 billion to acquire facilities to increase production. 

Lilly, meanwhile, has kicked off construction of a $2.5 billion plant in Germany to boost the production of its obesity treatments. The factory will open in 2027 and will ship worldwide, the US drugmaker said earlier this month. 

The company said it expects its investments in manufacturing and supply capacity to progressively increase production of its medicines throughout 2024 and beyond. Patients can find the status of their drugs’ supplies on a company website, Lilly said. 

--With assistance from Bill Haubert and Naomi Kresge.

(Updates with share move, comment starting in third paragraph.)

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