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Loss of exclusivity · Cardiometabolic

Zepbound patent expiration

Zepbound (Eli Lilly) is expected to face US generic competition from 2036. Same molecule as Mounjaro (tirzepatide), sold for obesity. Lilly 10-K: US compound patent 2036.

US loss of exclusivity
2036Company guidance
2025 worldwide sales
$13.5BEli Lilly
Therapeutic area
Cardiometabolic
US competition from
GenericsUS date shown

What the date means

Zepbound's US exclusivity date is based on company guidance. The date comes from the company's own filings or guidance. Secondary patents, new formulations or litigation can still move it. It is a peptide regulated as a drug rather than a biologic, so copies are generics. Peptides are harder to copy than typical pills, so generic uptake can be slower.

Who's lined up to copy Zepbound

Filed with the FDA Filed together with Mounjaro: in July 2026 Lilly received notice that multiple generic companies had applied to copy the drug before its patents expire, and said it intends to sue. The filers are not named.

Company (product)Stage
Several generic makers (not named by Lilly)Generics filed Jul 2026; Lilly to sue

Checked September 2026. Sources: Lilly 10-Q, Q2 2026

What changed for Zepbound

  1. Copies in the works
    Generic makers file to copy Mounjaro and Zepbound

    Lilly received notice that multiple companies had applied to sell generic tirzepatide before its patents expire, and said it intends to sue. Its US compound patent runs to 2036. Lilly 10-Q, Q2 2026

What's at stake for Eli Lilly

Zepbound is 21% of Eli Lilly's 2025 revenue ($13.5B of $65.2B). With Trulicity, Taltz, Verzenio and Mounjaro, the drugs tracked here add up to 77% of Eli Lilly's revenue losing US exclusivity by 2036.

Bars show each company's tracked drugs as a share of its total 2025 revenue. Zepbound is highlighted.

Other blockbusters losing US exclusivity in 2036

Sources

  1. Lilly 10-K 2025
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