The U.S. Food and Drug Administration has accepted two Abbreviated New Drug Applications (ANDAs) from Sandoz for proposed generic tirzepatide autoinjectors. Developed entirely in-house, the applications seek approval for all approved indications of Mounjaro and Zepbound, including type 2 diabetes, chronic weight management, and obstructive sleep apnea in adults with obesity.
Although commercialization remains years away, the filings mark an important milestone in what is expected to become the largest loss-of-exclusivity event in the GLP-1 market. Eli Lilly’s core U.S. patent on tirzepatide is expected to expire in 2036, while additional patents covering formulations, delivery devices, and methods of treatment could extend protection until approximately 2041.
If approved following patent expiry or other legal pathways, generic tirzepatide could expand patient access by lowering treatment costs and increasing competition. Generic medicines typically improve affordability for patients and healthcare systems, making therapies more accessible across diabetes, obesity, and related indications.
Sandoz strengthens position in GLP-1
Since becoming an independent company following its separation from Novartis in 2023, Sandoz has focused on expanding its global generics and biosimilars business. The company generated USD 11.1 billion in net sales during 2025 and markets approximately 1,300 generic medicines while maintaining more than 400 additional generic assets in development.
Generics account for roughly 70% of Sandoz’s business, with biosimilars, highly similar versions of approved biologic medicines that offer comparable safety and efficacy, contributing the remainder. The company has increasingly identified GLP-1 medicines as a long-term growth opportunity as major branded therapies approach the end of their exclusivity periods.
Branded medicines with projected sales exceeding USD 650 billion are expected to lose patent protection between 2026 and 2035, creating a significant opportunity for generic and biosimilar manufacturers. The wave of expiries is part of the broader pharmaceutical patent cliff reshaping the industry (also see: Pfizer’s impending patent cliff). Sandoz identified GLP-1 medicines as an emerging long-term growth area and said it is expanding its biosimilar development and manufacturing capabilities to support future growth.
Targeting one of the pharma’s largest franchises
Tirzepatide has become one of the fastest-growing medicines in the pharmaceutical industry. Eli Lilly markets the molecule under two brands. Mounjaro is approved as an adjunct to diet and exercise to improve glycemic control in adults and pediatric patients aged 10 years and older with type 2 diabetes. Zepbound is approved for chronic weight management in adults with obesity or overweight patients with at least one weight-related comorbidity, as well as for treating moderate-to-severe obstructive sleep apnea in adults with obesity.
Mounjaro generated approximately USD 23 billion in revenue during 2025, while Zepbound contributed about USD 13.5 billion. Combined, the two medicines generated more than USD 36 billion in annual sales, making tirzepatide one of the highest-grossing pharmaceutical franchises globally.
Patents protecting tirzepatide
Eli Lilly’s intellectual property strategy extends beyond the tirzepatide molecule itself. The company has built a layered patent portfolio covering the active compound, pharmaceutical formulations, manufacturing processes, and delivery technologies used in Mounjaro and Zepbound. These patents help protect the products from generic competition by safeguarding different aspects of their development and commercialization. The following patents illustrate how Lilly has combined compound and formulation innovations to strengthen long-term exclusivity for its tirzepatide franchise.
A stable tirzepatide formulation for diabetes and obesity treatment
Type 2 diabetes and obesity are among the fastest-growing chronic health conditions worldwide. While lifestyle changes remain the foundation of treatment, many patients require medicines that improve blood sugar control while promoting sustained weight loss. Tirzepatide, a dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist, has emerged as one of the most effective therapies for both conditions. However, peptide medicines require carefully designed formulations to remain stable throughout manufacturing, storage, and administration.
U.S. Patent No. 11,357,820 introduces a pharmaceutical formulation of tirzepatide optimized for subcutaneous injection. Rather than protecting the tirzepatide molecule itself, the patent focuses on the composition of the injectable product by combining tirzepatide with excipients such as sodium chloride or propylene glycol and dibasic sodium phosphate.
These components are formulated to improve shelf-life stability, maintain product integrity during use, and reduce discomfort at the injection site. The patent also covers preservative systems, dosage concentrations, and formulations designed for single-use autoinjector devices, supporting once-weekly administration for the treatment of type 2 diabetes and obesity.
The patent, titled “Pharmaceutical GIP/GLP-1 Co-Agonist Peptide Composition,” was filed on June 14, 2019, and was granted on June 14, 2022. It is currently active and is expected to expire on June 14, 2039. The listed inventors are Vincent John Corvari, Christopher Sears Minie, Dinesh Shyamdeo Mishra, and Ken Kangyi Qian. MaCharri Vorndran-Jones represented Eli Lilly in the filing.
Dual GIP/GLP-1 receptor agonist for type 2 diabetes
Type 2 diabetes affects approximately 90% of people living with diabetes and is characterized by elevated blood sugar levels caused by insulin resistance. Although existing treatments such as GLP-1 receptor agonists improve glucose control and promote weight loss, many patients remain inadequately controlled or experience dose-limiting side effects, including nausea and vomiting. Researchers have therefore sought therapies that target multiple metabolic pathways to improve efficacy while maintaining tolerability.
U.S. Patent No. 9,474,780 introduces a new class of dual incretin peptide mimetics that simultaneously activate the glucose-dependent insulinotropic polypeptide (GIP) receptor and the glucagon-like peptide-1 (GLP-1) receptor. By combining the activity of both naturally occurring incretin hormones, the compounds are designed to stimulate insulin secretion, suppress glucagon release, slow gastric emptying, and increase satiety, leading to improved blood glucose control and weight loss. The patent also describes modifications to the peptide structure and fatty acid side chain that improve stability against enzymatic degradation, reduce immunogenicity, extend circulation time to support once-weekly dosing, and maintain selective activity while minimizing stimulation of related glucagon and GLP-2 receptors.
The patent, titled “Dual GIP and GLP-1 Receptor Agonists,” was filed on January 5, 2016, and was granted on October 25, 2016. It is currently active and is expected to expire on January 5, 2036. The listed inventors are Bengt Krister Bokvist, Tamer Coskun, Robert Chadwick Cummins, and Jorge Alsina-Fernandez. Alejandro Martinez represented Eli Lilly in the filing.
Eli Lilly: Patents on tirzepatide and weight loss
Eli Lilly’s global patent filings peaked between 2018 and 2022, coinciding with the clinical development and commercialization of tirzepatide. During this period, Eli Lilly advanced the SURPASS Phase 3 clinical program for type 2 diabetes, secured regulatory approvals across major markets, and received U.S. FDA approval for Mounjaro in 2022. The company’s filings related to tirzepatide and weight loss also rose as it expanded patent protection around peptide formulations, dosing regimens, manufacturing processes, and obesity-related therapeutic applications.
Patent activity remained elevated through 2022 as Lilly prepared tirzepatide for obesity treatment, culminating in the FDA approval of Zepbound in 2023 following positive SURMOUNT trial results. The subsequent decline in published filings likely reflects the normal publication lag for recent patent applications rather than a reduction in research activity.
Sandoz: Patenting activity
Sandoz’s patent filings were concentrated between 2015 and 2018, when the company expanded its biosimilars pipeline and advanced several development programs under Novartis ownership. The peak in 2016 coincided with continued investment in biosimilars following the launches of Zarxio and Erelzi, as Sandoz broadened its intellectual property portfolio around biologics development, manufacturing, and formulations.
Patent filings declined after 2018 as the company shifted from early pipeline expansion toward commercialization and lifecycle management. Following its spin-off from Novartis in 2023, Sandoz focused on strengthening its biosimilars platform through investments in European manufacturing, acquisitions such as Just-Evotec Biologics EU SAS, and development of next-generation biosimilars rather than generating large volumes of new patent filings.
Sandoz: Top Technology Areas
Sandoz’s patent portfolio is heavily focused on pharmaceutical technologies, with the largest share of filings classified under preparations for medical, dental or toiletry purposes (A61K) and specific therapeutic activity of chemical compounds or medicinal preparations (A61P).
Significant activity is also seen in heterocyclic compounds (C07D) and general methods of organic chemistry (C07B), reflecting the company’s focus on pharmaceutical formulations, medicinal chemistry, and generic drug development.
Other technology areas include devices for introducing media into, or onto, the body (A61M), acyclic or carbocyclic compounds (C07C), technologies for adaptation to climate change (Y02A), investigating or analyzing materials by determining their chemical or physical properties (G01N), as well as control or regulating systems (G05B) and computational chemistry and cheminformatics (G16C).
Together, these technology areas demonstrate Sandoz’s broad research capabilities spanning drug formulations, delivery technologies, analytical methods, and computational tools that support pharmaceutical development.
Sandoz: Top Law Firms
Sandoz’s patent filings between 2015 and 2024 were supported by a broad network of intellectual property firms across multiple jurisdictions. Prüfer & Partner handled the largest number of filings, followed by Luedeka Neely, Griffith Hack, and Kawaguti & Partners. Other notable representatives include Zhongzi Law Office, Sandoz’s in-house IP team, Ter Meer Steinmeister & Partner, Lavery de Billy, and Leading Intellectual Property Firm.
The distribution of legal representatives reflects Sandoz’s global patent strategy, with filings managed through firms specializing in key pharmaceutical markets across Europe, North America, Asia, and Australia.