Lilly's Mounjaro, Zepbound supply situation worsens as most doses now face multi-month shortages

The ongoing shortage of Eli Lilly’s popular diabetes med Mounjaro doesn’t look to be letting up anytime soon, with the FDA extending its projection once again. Plus, most doses of the drug’s obesity counterpart, Zepbound, have now joined the ranks of the FDA shortage list.

Previously, the FDA had estimated Mounjaro would be in limited availability through this month. The new update extends the expected supply squeeze through the second quarter for all but one dosage strength of Mounjaro.

Lilly’s other tirzepatide product, Zepbound, had reportedly faced similar supply issues, but most doses were not listed in the FDA's shortage database until this week. The agency now lists the drug in limited supply for all but one dosage strength, as with Mounjaro.

The reason for the shortage is a reported “demand increase” for the drugs, according to the FDA.

While the company has long been working on a North Carolina manufacturing plant expected to help meet the demand surge, that site isn’t expected to be operational until the end of this year.

Products made at the plant will take even longer to make it to pharmacy shelves, with Lilly’s global manufacturing head, Edgardo Hernandez, telling NBC News that patients can expect supply from the plant “sometime next year.”

Lilly did not immediately respond to Fierce Pharma’s request for comment, but a spokesperson last month acknowledged that some patients may struggle to fill their prescriptions due to the “unprecedented demand for these products."

Alongside the North Carolina plant, the company is building a large Germany injectables plant that is expected to begin operations in 2027.

Amid the supply issues, the appearance of compounded and counterfeit versions of the meds has been on the rise around the country. Lilly in March issued a statement alerting patients to the safety risks of using such knockoff products.