FDA says most Zepbound and Mounjaro doses will stay in short supply through June

Most doses of Eli Lilly's tirzepatide medicines — Zepbound for weight loss and Mounjaro for type 2 diabetes — will stay in limited supply through June, according to an April 17, 2024, update on the FDA's drug shortage database ^[1].

Every dose strength except the 2.5-milligram version of each brand is listed in shortage ^[1][2]. An earlier update said some doses of both drugs would have limited availability through April ^[1]. Zepbound was approved in November 2023 and went into shortage in April, according to the FDA ^[2]. Zepbound and Mounjaro contain the same active ingredient, tirzepatide ^[2].

Lilly attributes the shortage to demand outpacing its ability to make enough of the drug for both diabetes and weight loss ^[2]. "For the near term, we are going to be in this limited availability, which may cause delays across some of the doses for both Mounjaro and Zepbound," said Rhonda Pacheco, Lilly's group vice president for diabetes and obesity. "We are working so hard every day to make sure that we increase that capacity as fast as we can to get these medications in patients' hands" ^[2]. Lilly has not said exactly when supply will normalize ^[2].

A Lilly spokesperson told CNBC: "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." The spokesperson said Lilly expects its manufacturing and supply investments "to progressively increase production of our medicines throughout 2024 and beyond" ^[1].

Lilly said in February that it had doubled production capacity for this class of drugs by the end of 2023 and would expand with "equal urgency" in 2024, with the largest increases coming in the second half of the year. By then, it expects production of sellable doses of these drugs to be at least 1.5 times the level of the second half of 2023 ^[1]. A new plant in Concord, North Carolina, is set to start making the drugs as early as the end of the year, with products available to ship in 2025, and Lilly plans other sites in Germany and two more in Indiana ^[1]. Edgardo Hernandez, who leads global manufacturing at Lilly, said patients can expect to see products from the Concord plant on pharmacy shelves "sometime next year" ^[2].

The shortage is not limited to tirzepatide. Some doses of Novo Nordisk's Wegovy, a semaglutide weight-loss drug, and its diabetes counterpart Ozempic are also listed as in short supply ^[1].

Why it matters for patients

For someone already taking Zepbound or Mounjaro, limited availability can mean calling multiple pharmacies to fill a prescription. Amanda Cella, a 37-year-old in South Jersey who was prescribed Zepbound in February, said she contacted independent shops plus retail and hospital pharmacies in New Jersey and Philadelphia, and none had the drug. "I wish I were exaggerating when I say I called every Walmart pharmacy in the state of New Jersey," she said ^[2]. Cella said the drug appeared to be available on Lilly's telehealth platform, LillyDirect, but was on backorder, and that she had enough doses to cover a few more weeks. If she could not find more, she said, she would consider getting the drug from a compound pharmacy ^[2].

Not every dose is affected equally. The 2.5-milligram starting doses of both Zepbound and Mounjaro are the only strengths not listed in shortage ^[1][2]. The FDA database tracks availability by dose strength, and it does not show how long an individual patient might wait for a given prescription ^[1][2].

What happens next

The FDA currently lists the affected doses as limited through June ^[1][2]. Lilly has not given a date for when supply will catch up ^[2]. Its Concord plant is expected to begin production as early as the end of 2024, with product reaching pharmacies in 2025, and the company expects its biggest supply increases in the second half of 2024 ^[1][2].