Obesity affects over 1.9 billion people worldwide.1 In 2024, global spend on anti-obesity medication exceeded $30 billion for the first time, which is over a ten-fold increase since 2020, as reported by IQVIA.2 This is driven by an unprecedented and ever-increasing demand for appetite-suppressing drugs, with Novo Nordisk being a leader in the research, development and manufacture of weight-loss drugs.
Two of Novo Nordisk's key products are injectable drugs Ozempic® and Wegovy®, comprising the same active ingredient, semaglutide, in different doses. Ozempic® was originally found to regulate blood sugar and is approved as a treatment for type 2 diabetes, while Wegovy® was subsequently approved for weight loss and management. While enabling patients to lose weight, a knock-on effect is that the risk of cardiac events, such as heart attacks and strokes, are reduced.
How does semaglutide work?
Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist which mimics the natural hormone GLP-1 and binds to GLP-1 receptors in the brain. Broadly, semaglutide works by suppressing hunger and increasing satiety.
Specifically, semaglutide increases levels of incretins, which are hormones produced naturally by the stomach during eating, thereby increasing insulin levels when needed. Semaglutide also suppresses glucagon production, thus reducing the amount of glucose released and synthesised by the liver.
Semaglutide also delays gastric emptying, providing a feeling of fullness and satiety.
Semaglutide has been shown to result in the highest total body weight loss percentage of around 14.9%, within FDA-approved anti-obesity medications.3
Novo Nordisk's semaglutide patent portfolio
Unsurprisingly, Novo Nordisk's patent portfolio stemming from semaglutide is extensive, in terms of scope and territorial protection.
Primary patents in this area are directed to the broad, core concept, i.e., the chemical composition of semaglutide, as well as formulations thereof, preparation methods, methods of treatment (in countries like the US, where protection of such methods are allowable) and uses of semaglutide. So-called 'secondary' or 'follow-on' patents target other aspects relating to semaglutide, e.g., peripheral or minor modifications, including new delivery devices, dosing regimens and formulations. The follow-on patents aim to extend Novo Nordisk's market exclusivity by covering incremental improvements and new uses. Such filing strategy is known as "lifecycle management".
Novo Nordisk have also used mechanisms designed especially for pharmaceutical products to extend the lifetime of their patents beyond the standard 20-year term. This allows for some compensation of delays in regulatory approval processes and therefore effectively extends the market exclusivity. In Europe, Supplementary Protection Certificates (SPCs) extend the duration of a patent by up to 5 years (with a potential additional 6-month extension for products that have undergone paediatric testing). A similar mechanism is available in countries such as the US, Japan and Australia, termed Patent Term Extensions (PTEs).
Novo Nordisk's core patents in China are due to expire in 2026. Thus, Chinese generics companies are likely gearing up to begin manufacture of generic versions of semaglutide. The secondary patents, e.g., in the US, are not set to expire until 2033, thus providing Novo Nordisk with prolonged market exclusivity and delaying the launch of generics in other territories.
This is a snapshot of how Novo Nordisk is using creative patent filing strategies and different aspects of the patenting systems in various jurisdictions to their benefit. The use of SPCs and PTEs means that the entry of generics into different territories will be unpredictable and staggered and thus potentially causing their competitors difficulty. Indeed, filing in territories such as the US means that protection of, e.g., methods of treatment, can be obtained, which are excluded from patentability in territories including Europe and Japan. Furthermore, Novo Nordisk will have strengthened their market position by patenting the same drug (semaglutide) for different uses, e.g., semaglutide for use in the treatment of diabetes and separately for use in the treatment of weight loss (termed 'second medical use' in Europe).
Novo Nordisk's filing strategy shows that patenting does not and should not stop after protection of the core concept; assessing the peripheral and/or incremental aspects relating to a drug can be key to retaining prolonged market exclusivity.
Can commercial success equate to inventive step at the EPO?
With the phenomenal and lucrative success of semaglutide and its far-reaching patent portfolio, it is to be expected that Novo Nordisk's patents will be vulnerable to attack by other 'Big Pharma' players in the weight loss drug arena who would like to 'clear the way' before the natural expiry of the patents.
A recent example relates to Novo Nordisk's European patent4 directed to the use of semaglutide in a specific dosage and formulation for treating obesity, which was opposed by Teva and Galenicum Health.5 The European Patent Office (EPO) revoked Novo Nordisk's patent on the ground that it lacked an inventive step.
Novo Nordisk appealed and were challenged with demonstrating why the choice of semaglutide, at the particular dose and pH specified in the claim would have not been obvious to the skilled person. The closest prior art taught that semaglutide was suitable for treating obesity and suggested a dosage range overlapping with the claimed range.
Novo Nordisk's defence relied on post-published evidence (i.e. evidence published after the priority date of the patent), including BBC reports in which experts described semaglutide as a "game a changer" in obesity treatment, and clinical trial data. Ultimately, the EPO's Board of Appeal (BoA) rejected this evidence as basis for establishing an unexpected technical effect of the claimed subject matter and emphasised that commercial success could not retroactively establish inventive step if the claimed features were already suggested by the prior art at the priority date. Thus, even if hailed a miracle drug, it does not necessarily mean that patent protection is guaranteed.
Footnotes
1. Weight loss outcomes with semaglutide based on diabetes severity using the individualized metabolic surgery score, Ghusn, Wissam et al., eClinicalMedicine, Volume 72, 102625
2. https://www.iqvia.com/locations/emea/blogs/2025/01/outlook-for-obesity-in-2025-more-than-a-transition-year
3. Weight loss outcomes with semaglutide based on diabetes severity using the individualized metabolic surgery score, Ghusn, Wissam et al., eClinicalMedicine, Volume 72, 102625
4. EP 2866825
5. T 1701/22
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