The Lancet article

Anti-obesity drugs: effective, but not affordable. This may soon change

Over one billion people worldwide live with obesity, with a particularly rapid increase in low- and middle-income countries

by Maria Rita Montebelli

26 March 2026

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5' min read

Translated by AI

Versione italiana

Key points

Expiring patents and biosimilars 'moment'
The WHO obesity guidelines
The charge of the oral anti-obesity
The fake phenomenon
The future and global answers[Insert key point]

5' min read

Translated by AI

Versione italiana

This week's Lancet cover story tackles the thorny topic of "how to make the treatment of obesity fairer", in a wide-ranging reflection on how the anti-obesity drug landscape is changing. Between semaglutide's patent expiry, the arrival of oral options and very low-cost biosimilars, 2026 will be a crucial year for the anti-obesity drug market and, consequently, for clinical practice. And amidst costs that are still prohibitive for many, limited production capacity by pharma companies and constraints in the supply chain (and cold storage for injectables), that billion obesity sufferers worldwide are watching this story unfold with great attention. Because the current challenge is no longer to prove that incretin-based drugs (GLP-1 receptor analogues such as semaglutide, dual agonists such as tirzepatide and future triple agonists such as retatrutide) work. But ensure that they actually reach everyone who needs them.

The year 2026 could go down in history as the watershed in the fight against obesity. After a decade of exponential growth, drugs based on GLP-1 receptor agonists are radically transforming clinical weight management, with the market set to be worth $150 billion by 2035. But of course, this story cannot only be read from the business angle. More than a billion people worldwide live with obesity, with a particularly rapid increase in low- and middle-income countries. But precisely where the need is greatest, access to treatment remains limited by high costs, insufficient manufacturing capacity and fragile supply chains. An imbalance that, according to experts, could, however, begin to diminish in the coming months.

Expiring patents and 'moment' biosimilars

Starting in April, the patents of semaglutide, the blockbuster drug (Ozempic®, Wegovy®) that inaugurated this innovative chapter in obesity therapy (before 'sema', liragluglutide, also from the Danish Novo Nordisk, had tried, but with modest results) will begin to expire in several large emerging markets - including Brazil, Canada, China, India and Turkey - which, taken together, account for around 40% of the world's population. And the effect could be disruptive.

A number of Chinese and Indian pharma companies are preparing to launch biosimilar versions of 'sema' on a large scale, triggering competition similar to that which affected anti-retroviral HIV drugs in the early 2000s. According to preliminary estimates (published as a pre-print in MedRxiv), an injectable biosimilar version could cost as little as $28 per person-year. And by the end of 2026, these therapies could be on the market in 160 countries, accounting for 84% of the anti-obesity drug market. A truly game-changing prospect, which for health systems and investors would represent a real revolution, although not without risk.

The WHO Obesity Guidelines

Responding to such a large number of people with obesity is not just a matter of lowering drug prices. The World Health Organisation has already placed GLP-1 agonists on the list of essential drugs and issued 'global' guidelines for their use. However, at the same time sending a very clear message: systemic tools are needed in the fight against obesity. Centralised purchasing, tiered pricing, voluntary licensing and local production will be crucial to prevent innovation from being confined to the richest markets. In the meantime, big pharmaceutical companies are trying to defend their market shares with strategies such as 'patent thickets', i.e. multiple patents targeting a single product, also linked to delivery devices, in addition to the active ingredient. A recent analysis (also published in the Lancet last February) of patents related to drug-device combinations containing GLP-1 receptor agonists found that 57% were patents on devices, without any reference to active ingredients, chemical structures or therapeutic class. This approach could slow down the development of biosimilars.

The charge of the oral anti-obesity

But there is another key front: that of anti-obesity drugs in oral formulation, i.e. pills. Current injectable drugs are also expensive because of the disposable 'pens', which can cost up to 68 times more than all other production costs put together. And they also require cold chains, which are difficult to guarantee in many countries.

That is why pill versions, stable at room temperature, promise to change the rules of the game: easier to produce, transport and store, and definitely cheaper. Two molecules are leading the race: oral semaglutide (Novo Nordsisk), already approved in the US for weight loss, and orforglipron (Lilly), expected by the end of the year. The latter, a non-peptide small molecule (thus a truly innovative drug), could be even cheaper to produce on a large scale. The phase 3 study ACHIEVE-3, published in the same issue of the Lancet, compared head-to-head the efficacy and safety of orforglipron and oral semaglutide in about 1700 subjects with diabetes not controlled by metformin alone, with respect to the endpoints glycated haemoglobin and weight loss (secondary endpoint). Orforglipron hit both targets better, producing a 2.2 percentage point reduction in glycated haemoglobin (compared to 1.4 per cent for sema) and 73.6 per cent greater weight loss than oral semaglutide at the highest dosages. In short, the efficacy of oral drugs is not in question and the point has been amply made. But here, too, the decisive factor will be price.

The fake phenomenon

There is, however, a fair amount of optimism for the future of the fight against obesity. But the Lancet columnists issue awarning, because unfortunately, and precisely in our latitudes, real risks are taking shape. In Europe and the United States, patents still remain in force and, with them, the high costs of these drugs. But this has already fuelled a parallel market (another publication in Lancet offers an extensive analysis). As of 2022, there has been a significant increase in counterfeit drugs in almost 60 countries. And the arrival of oral versions (which are easier to produce) could exacerbate the 'fake' phenomenon, which could also fuel the growing popularity of these drugs for purely cosmetic purposes (especially in spring, with the sad phenomenon of do-it-yourself and passing the word to get through the infamous 'swimming costume test'). The unsupervised and large-scale use of these drugs (which represents a real risk and would require stricter regulations), coupled with the scarcity of data on their long-term effects, does not make many experts sleep soundly.

The Future and Global Responses

This fact brings us to another knot, inherent in the very nature of obesity, a chronic, complex and above all relapsing disease. There are many studies that have shown this (in addition to the daily clinical experience of those who deal with this disease): stopping treatment almost invariably leads to a recovery of the weight lost within 18 months. And this means that long-term 'maintenance' strategies are still to be defined. In short, whichever way you look at it, the editorialists conclude, to think that GLP-1 analogues alone can solve the global obesity epidemic would be naive. Poverty, urbanisation and poor diet (including cheap junk food) remain determining factors.

Certainly, however, these drugs can be a key part of an integrated approach that integrates prevention, care and treatment. And this is the direction in which the WHO's global plan (WHO Acceleration Plan to Stop Obesity) is moving, which sets the goal of reducing the prevalence of obesity by 5%, by 2030, in 34 countries, with a target therefore of 1.3 billion people.

GLP-1 analogues have already transformed the debate (and clinical practice) on obesity and public health, catalysing scientific, political and financial attention. The year 2026 could mark the transition from niche innovation to a global solution, truly within everyone's reach. Especially for those who need it most.