Six reasons why it is so difficult to get weight loss medication

About 3.8 million people in the United States – four times as many as two years ago – are now taking the most popular weight-loss drugs, according to the IQVIA Institute for Human Data Science, an industry data provider.

Some of these recipes are for diabetes. The drugs are Novo Nordisk's Ozempic and Wegovy (the same drug sold under different brand names), and Eli Lilly's Mounjaro and Zepbound (also the same drug).

The pent-up demand is even greater because many people who want the drugs can't find or afford them. Without insurance coverage, people have to pay out of pocket. If they get a coupon from Eli Lilly, people with commercial insurance will pay $550 a month for Zepbound. For those who have commercial insurance, a Novo Nordisk coupon for Wegovy reduces the pharmacy bill by $500, bringing the cost to about $1,000 per month.

And the expectation is that interest will continue to grow.

2. The offer is limited.

Novo Nordisk and Eli Lilly have tried to respond by ramping up production, but they have been unable to generate enough to meet demand.

Only a limited number of factories in the world are ready and available to make the injectable drugs, which are more difficult to manufacture than pills. Adding to the complexity, each company produces at least five dosage strengths of its drug.

“These are complicated sites, technically demanding work, very capital intensive, populated with machines that are highly specialized and often made in not-so-large companies,” David Ricks, CEO of Eli Lilly, said last month.

For Eli Lilly, which sells Zepbound for weight loss, a critical bottleneck is making enough of the pens used to inject the drug.

Novo Nordisk, the manufacturer of Wegovy, has struggled even more than Eli Lilly to make enough of its drug, though the company is trying to catch up. It said it more than doubled its supply of doses for new patients in January, and estimated the drug would be in pharmacies within a few weeks.

This situation is unusual, says Erin Fox, an expert at the University of Utah who tracks drug shortages. Most of the shortage concerns older medicines for which there are few financial incentives to manufacture the medicines. “If there's a very profitable drug out there, we usually don't see shortages,” she said.