'Unprecedented' demand for Eli Lilly's Zepbound sparks US supply constraints

Once again, a medicine in the popular GLP-1 class of diabetes and weight loss therapies is facing supply hurdles.

This time, the drug that pharmacies can't consistently keep on shelves is Eli Lilly's GIP/GLP-1 obesity offering Zepbound, thanks to what the company describes as "unprecedented" demand. 

While the weight loss shot is not currently listed on the FDA’s shortage list, pharmacies across the nation are struggling to keep the drug on shelves, Bloomberg News reports.

For example, Amazon Pharmacy, a third-party dispensing provider for Lilly, lists four out of six dosage strengths as “unavailable."

The online pharmacy also reports that Lilly’s diabetes injection Mounjaro (tirzepatide) is unavailable. The drug shares the same active ingredient as Zepbound.

“While Lilly continues to manufacture and ship all doses of Zepbound, due to the unprecedented demand for these medicines, some patients may experience difficulty when trying to fill their prescription at their pharmacy,” a Lilly spokesperson told Fierce Pharma in an emailed statement.

Patients whose treatment regimens are disrupted can try nearby pharmacies and reach out to healthcare providers if they experience continued disruptions, Lilly's spokesperson said.

The drugmaker is “moving with purpose and urgency to ensure our innovations are available to those who need them,” the spokesperson added.

At Rite Aid, a spokesperson said high demand for Zepbound has “created some sporadic supply constraints." Walgreens, too “continues to work with supplier and distribution partners to help meet patient demand,” a company representative told Fierce Pharma.

As for Mounjaro, the FDA has acknowledged an ongoing shortage. Certain doses are expected to be in short supply until the end of the month.

While branded Zepbound and Mounjaro may be in short supply, fraudulent copycats are reportedly swarming the market.

Earlier in March, Lilly alerted patients to the safety risks of using compounded or counterfeit versions of tirzapatide, which it has found often contain bacteria and high impurity levels. The company reiterated its commitment to pursuing legal action against those who falsely claim the Mounjaro or Zepbound name, including “certain medical spas, wellness centers, and compounding pharmacies.”