Amylin analogues for weight loss: clinical and patent trends

Blog

05 Dec 2025

In this article we discuss the ever-growing popularity of weight-loss drugs and the new candidates that are emerging as alternatives to the well-known GLP1-based drugs that currently dominate the market.

Background

As reported in our previous article (here), the popularity of GLP1 receptor agonists (‘GLP1-based drugs’) as weight loss drugs has surged in recent years. Names such as “Ozempic®”, “Wegovy®” and “Mounjaro®” have become widespread in both traditional and social media. Prescriptions of these drugs increased by 400% from 2021 to 2023 in the United States alone¹. GLP1-based drugs work by supressing appetite and enhancing satiety (i.e., a feeling of ‘fullness’), thereby reducing calorie intake and promoting weight loss.

Due to the popularity of these drugs, it is unsurprising that pharmaceutical companies are investing more into alternative weight loss drugs in an effort to secure a monopoly in this competitive market.

Amylin analogues

Amylin analogues have appeared at the forefront as a weight loss drug candidate. Amylin is a naturally occurring hormone which is co-secreted with insulin from the β-cells of the pancreas in response to increases in certain nutrients (glucose and fatty acids) following a meal. Amylin has been found to have similar roles to insulin. For example, it has been shown to increase glucose uptake from peripheral tissues, thereby reducing blood glucose levels, and to inhibit the release of glucagon, a hormone that promotes glucose secretion into the blood. For these reasons, an amylin analogue, pramlintide (marketed as Symlin®), is an approved therapy for type 2 diabetes.

Amylin has also been associated with weight loss. It has been shown to slow gastric emptying and amylin receptors have been found in the key appetite-regulating areas of the hypothalamus in the brain². This has led to the suggestion that amylin can function as a neuropeptide in a similar manner to GLP-1, which has been reinforced by studies showing that the administration of compounds that inhibit the function of amylin leads to an increase in food intake in rodents³. Additionally, patients taking pramlintide have been shown to experience weight loss⁴.

Amylin’s function as an appetite inhibitor is two-pronged:

Indirectly: it slows gastric emptying, which stimulates the vagus nerve, a key nerve that provides communication between the brain and the stomach, to signal that the stomach is full.
Directly: it binds directly to amylin receptors in the brain to promote satiation.

By way of comparison, GLP-1-based drugs act by mimicking the GLP-1 hormone that is secreted into the bloodstream from the lower gastrointestinal tract in response to greater nutrient availability following food consumption. One of the target sites of GLP-1, and thus GLP1 receptor agonists, is the brain, where it acts to suppress appetite and promote satiety (or a feeling of “fullness”).

Clinical indications

Whilst the GLP-1 based drugs have been considered a success in promoting weight loss, the therapies do cause gastrointestinal side effects, in particular nausea, diarrhoea and vomiting. Many users find these effects intolerable.

In recent months, data has been published showing the favourable effects of amylin analogues in clinical trials.

Eli Lilly has a published phase 1 data showing weight loss of around 11% over a 12-week period using their amylin analogue, eloralintide, alongside lifestyle interventions⁵. This is particularly impressive given that Wegovy® promotes an average weight loss of around 15% over two years⁶. The number of reported side effects associated with eloralintide was relatively low.

Novo Nordisk has also published phase 3 data showing an average weight loss of 11.8% using cagrilintide, a long-acting amylin analogue, alongside lifestyle interventions over a period of 68 weeks compared to 2.3% with placebo⁷. 31% of participants achieved ≥15% weight loss with the drug. Cagrilintide was also described to be well-tolerated.

As such, current data suggests that amylin analogues have the potential to drive weight loss without the same level of side effects as seen with GLP-1 receptor agonists.

Combinations of GLP-1 agonists with an amylin analogue have also shown impressive results. Novo Nordisk has published phase 3 data showing that a dual therapy comprising cagrilintide and semaglutide (the GLP-1 agonist in Wegovy®), coupled with lifestyle interventions, achieved an average of 13.7% weight loss in patients with type 2 diabetes, who are also overweight or obese, over a period of 68 weeks⁸.

In March 2025, Roche entered an exclusive collaboration and licensing agreement with Zealand Pharma to co-develop and co-commercialise Zealand Pharma’s amylin analogue, petrelintide, as a therapy for obesity in combination with Roche’s dual GLP-1/GIP receptor agonist, CT-388⁹.

Clinical trials are also ongoing looking into the combination of Eli Lilly’s eloratintide with tirzepatide (a dual GIP/GLP1 receptor agonist sold as Mounjaro®).

Patent data and research

Perhaps unsurprisingly, the trend in patent filings to both GLP1 and amylin-based therapies appears to match the market.

Since 2003, patent filings directed towards amylin-based therapies to promote weight loss/ as obesity treatments have fluctuated a little but have generally been relatively stable. In contrast, patent filings for GLP1-based therapies are much higher and have fluctuated dramatically over a 20-year period, with a stark increase seen in 2023. This increase likely reflects the recent surge in interest in the weight-loss drug market following the success of therapies such as Wegovy®, for example, which entered the commercial market for weight management in June 2021. This also appears to have prompted competition amongst pharmaceutical companies to find improved GLP1-based therapies, including combination therapies. Indeed, a notable increase in priority filings for a combination of GLP-1 and amylin was observed in 2023. This is perhaps not unexpected given the GLP-1/amylin combination therapies that are currently being investigated by Eli Lilly and Novo Nordisk.

When looking at the highest filing applicants over the same 20-year period, again, the patent data is largely consistent with the big players in the market. Top filers include Amylin Pharmaceuticals, AstraZeneca (AZ), Novo Nordisk, Zealand Pharma, and Pfizer.

Amylin Pharmaceuticals were the initial big filers, with the greatest number of patent families, i.e., patent applications relating to the same/similar inventions and linked by priority claims. The number of patent families peaked in 2012 before falling rapidly. In 2012, BMS acquired Amylin Pharmaceuticals and, as part of the acquisition, AZ made a billion dollar cash payment to make Amylin Pharmaceuticals a wholly owned subsidiary within an existing BMS/AZ collaboration for the research, development, and commercialization of diabetes drugs. AZ fully acquired BMS’s stake in the partnership in 2013, taking full ownership of the diabetes assets and operations. AZ did show a peak in filings between 2013 and 2014 following the acquisition, however, the number of filings appears to have dropped off since then. The reduction in filings to amylin-based therapies may reflect the fact that AZ’s lead in their weight loss program is currently AZD5004, a GLP-1 receptor blocker licensed from Eccogene¹¹ in November 2023. However, amylin-based therapies are clearly still of interest because AZ has recently presented early data for its long-acting amylin receptor agonist, for AZD6234. It will thus be interesting to see if there are further applications to amylin-based drugs in the pipeline.

Novo Nordisk’s presence as one of the top filers is unsurprising given its dominating role in the weight-loss drug market due to the proprietary status of Wegovy® and Ozempic®. The number of filings directed towards amylin-based therapies filed by Novo has declined in recent years. However, this may change as Novo looks to expand its portfolio of weight loss drugs. Indeed, following the revocation of a third patent in their GLP1-based family in May this year, it seems that Novo may need to seek alternatives to maintain its monopoly in this field.

Pfizer has shown a low but steady rate of filings between 2005 to 2015, although this has since dropped off. Pfizer has not been a major player in the weight loss drug market to date; however, they appear to be preparing to enter the market. Although their proposed GLP1-based pill had to be scrapped earlier this year following evidence of liver toxicity in a Phase III trial¹², Pfizer has recently acquired Metasera, a biopharmaceutical company specialising in obesity therapeutics. Amongst the pipeline of Metasera’s drugs is an amylin analogue, which is currently being evaluated as a monotherapy and a combination therapy with a GLP1 agonist¹⁰.

It is clear that there is a race amongst the pharmaceutical companies to have the next blockbuster weight-loss drug. Amylin appears to be a clear contender based upon the recent surge in patent filings and the publication of favourable clinical trial data.

Regardless, the increase in investment and development of new therapies shows that weight-loss drugs are here to stay. It will be interesting to see how the market continues to develop.

Methodology

The patent filings/families are based on data from PatBase, a patent data and analytics platform, The search criteria were developed using combinations of keywords and classifications. This data emphasises trends and specific points of interest; it is not intended to achieve exhaustive filing statistics for subject areas or assignees. Due to an 18-month delay from filing to publication of a patent application, a full dataset for 2024 or 2025 was not available.

References:

By Emma Lyons, Trainee Patent Attorney and Sarah Gibbs, Partner, Appleyard Lees