Regeneron Pharmaceuticals Inc (REGN) Stock Research Report

An Eye Drug, an Eczema Drug and a Race

If an older relative of yours has had injections in the eye to protect their sight, there is a fair chance the medicine was EYLEA. If a friend's severe eczema or asthma finally calmed down after years of creams and inhalers, the drug may well have been Dupixent. Few people know the name of the company behind both: Regeneron, which invents, makes and sells medicines of this kind.

For years, EYLEA was Regeneron's main source of income. Now cheaper copies of it are winning patients, and the company is counting on two successors. One is EYLEA HD, a stronger version of the same eye drug. The other is Regeneron's share of the profits from Dupixent, which its partner Sanofi sells around the world. So far, the two successors are keeping up with the decline. Is that strength earned, or borrowed from a passing change in a contract?

What the Company Does

Regeneron's medicines are antibodies, that is, drugs built from proteins like those the body uses to fight infection. Its medicines treat diseases of the eye, allergies and inflammation, cancer, heart disease and several rare illnesses. The money, however, reaches Regeneron in two very different ways.

In the United States, Regeneron sells EYLEA and its higher-dose version itself. A retina clinic orders the vials from a wholesaler and gives the injections; the wholesaler then pays Regeneron. In 2025, US sales reached $2.8 billion for the older dose and $1.6 billion for the new one.

Only a handful of wholesalers stand between Regeneron and the clinics, and they are large. Two of them bought 77% of Regeneron's gross product sales in 2025. Outside the United States, Bayer sells both versions of the eye drug and shares the profits with Regeneron.

Dupixent travels by another path. Sanofi sells it all over the world. In 2025, those sales came to $17.8 billion. None of that sum is Regeneron's revenue: Regeneron books only its share of the profits. The two companies amended their contract for the sixth time in October 2026.

Regeneron presents itself as a complete biotech, one that handles invention, manufacturing and sales on its own. In 2025 it added a treatment for multiple myeloma, a blood cancer, to its cancer medicines. Even so, one of its largest sources of income depends on how much Sanofi sells, and on terms that Regeneron negotiates but does not set alone.

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Legal Notes and Methodology

Producer and publisher: Francesco Monterosso · ReasyPort
Financial information reference: 2026-03-31
Legal contact: legal@reasyport.com

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Regeneron Pharmaceuticals Inc (REGN) - Stock report