A class of drugs first developed for diabetes that have become blockbuster weight-loss treatments. They suppress appetite by slowing digestion. The two dominant products are Wegovy, made by Novo Nordisk, which mimics the GLP-1 hormone, and Zepbound, made by Eli Lilly, which targets both GLP-1 and an additional hormone called GIP, thought to enhance weight loss.
Many insurers, including Medicare, America's public-health scheme for the old, do not cover obesity drugs unless tied to another condition. IQVIA, a health-data firm, says that more than half of obesity prescriptions in America are paid for out of pocket. Medicare, which covers 66m Americans, dropped a plan to reimburse obesity drugs.
The market is currently a duopoly between Novo Nordisk and Eli Lilly, though more than 100 companies are developing weight-loss drugs. Analysts expect the market to exceed $90bn by 2030, with Lilly holding 47% and Novo 40%. Both firms are also developing oral pills as successors to their injectable treatments.
On September 22nd 2025 Pfizer said it would pay $7.3bn for Metsera, a recently listed biotech firm working on next-generation weight-loss treatments. The same day Roche, a Swiss drugmaker, said it would begin late-stage trials of its own candidate the following year; earlier in 2025 it struck a $5.3bn deal with Zealand to co-develop and sell the smaller Danish firm's promising medicine. In June 2025 Innovent, a Chinese company, won approval from China's drug regulator for a novel GLP-1 injection to treat obesity; it said its anti-diabetes formulation had likewise been approved in September. These rival offerings look unlikely to clear all clinical and regulatory hurdles before 2028 at best, implying the bulk of the market remains with the two incumbents until then.
About one in eight American adults has taken a GLP-1 drug for weight loss, according to Gallup. KAM, a research firm, estimates that between 4% and 7% of British adults are users—a similar proportion to the number of vegetarians (5%) or those with food allergies (6%). In Britain 58% obtain the medication privately, 32% through the National Health Service and 10% in other ways. Global spending on GLP-1 drugs reached roughly $54bn in 2024. Most users come from middle- or high-income households.
Their rising adoption is one factor suppressing demand for packaged food. The restaurant industry is also adapting: KAM finds that 57% of GLP-1 users plan to visit restaurants for special occasions only, prompting high-end and casual eateries alike to offer smaller, premium-priced portions.
Mounjaro (Eli Lilly) became legally available in India in March 2025; Wegovy (Novo Nordisk) followed in June. Consumption of Mounjaro tripled from March to April. Between 2021 and 2024 Indian sales of weight-loss drugs grew five-fold to $72m. Jefferies, an investment bank, predicts India's market could grow to $1bn. Global annual sales of weight-loss drugs stand at $24bn and are set to rocket to $150bn in the next decade.
Starting at around $200 a month, Eli Lilly and Novo Nordisk's Indian offering costs as little as a fifth of American prices, but a year's supply can still be roughly equivalent to India's GDP per person. When the semaglutide patent expires in India in 2026, generics giants such as Cipla and Lupin will sprint to produce knock-offs; some analysts predict a 95% nosedive in price. Dr Reddy's plans to launch a generic version of Wegovy in 87 countries.
South Asians are unusually genetically predisposed to fatty-liver disease; Novo Nordisk's clinical trials suggest semaglutide might reduce it by 37%. Tirzepatide and semaglutide are injectables requiring cold storage—a tough ask in a hot country with patchy logistics chains. India's Mankind Pharma is expecting trial results by the end of 2025 for what would become India's first oral weight-loss drug that could rival injectables.
The latest forecasts in the Lancet project that more than half of adults and one in three children and adolescents will be obese or overweight by 2050. The annual global cost of obesity alone is forecast to reach $4.3trn by 2035. The economic burden of linked conditions—diabetes, cardiovascular disease and others—will add trillions more. Novo Nordisk is running a Childhood Obesity Prevention Initiative, a controlled study across six cities in Brazil, Canada, France, Japan, South Africa and Spain, evaluating dietary and physical-activity interventions among 6,000 children from disadvantaged communities.
Citeline, a research firm, reckons global sales of GLP-1s will exceed $26bn in 2025—double the figure in 2024. America accounts for four-fifths of sales. Two-thirds of the world's 1bn obese adults live in poorer countries.
In early 2026 patents on semaglutide—the active ingredient in Wegovy—will expire in several emerging markets, including Brazil, China, India and Turkey. At least a quarter of the world's obese people live in countries where semaglutide will lose protection. At least ten Indian versions of semaglutide are in late-stage trials; analysts expect generics to sell initially at about a third of the original price, with further decreases as competition intensifies. JPMorgan Chase expects India's GLP-1 market to grow from $179m in 2025 to $1.5bn by 2030. The Indian government is subsidising local manufacturers of GLP-1 drugs.
In China, home to more obese adults than anywhere else, the state-backed insurance scheme excludes weight-loss treatments, making price decisive. Around 20 semaglutide-based drugs are racing for approval. Unlike Indian firms, Chinese companies are also innovating: in June 2025 regulators approved mazdutide, developed by Innovent in partnership with Eli Lilly, which proved about as effective as Lilly's own version in trials. Novo Nordisk earmarked $2bn in March 2025 to license a promising experimental weight-loss drug developed in China; in June Regeneron, an American biotech firm, struck a $2bn licensing deal with Hansoh Pharmaceuticals, another Chinese company.
Both Eli Lilly and Novo Nordisk have developed pill-based alternatives to the injectable drugs. Although analysts reckon the pills, once approved, will be priced similarly to the injections, they will be especially useful in poorer countries, where the cold supply chains required for injections are often unreliable.
GLP-1s may also treat sleep apnoea, kidney disease and Alzheimer's disease. Semaglutide's anti-inflammatory and metabolic benefits have led to its being tested as a treatment for mild cognitive impairment. There is also hope that GLP-1 agonists might help prevent certain forms of cancer.
GLP-1 RAs are being investigated for Parkinson's disease, heart failure, drug and alcohol addiction and arthritis (because weight loss reduces joint strain). A pair of recent studies showed no positive effect for Alzheimer's disease.
Healthy people are increasingly seeking out GLP-1 RAs in the hope that they will preserve health for longer and even extend life. Preliminary work, mostly on animals and cell cultures but also including studies of people taking the drugs on prescription, suggests GLP-1 RAs ameliorate several "hallmarks" of ageing—distinct, interlinked harmful phenomena that affect a wide range of tissues and worsen over time.
Chief among these is "inflammaging", the chronic rise in low-level inflammation that accompanies ageing. GLP-1 RAs appear to inhibit this in several ways, including stopping the formation of protein complexes that trigger inflammatory responses. The drugs also promote the recycling of failing cellular machinery—worn-out mitochondria and misfolded proteins—keeping cells ticking over for longer. They help modulate biochemical pathways that sense nutrients and orchestrate appropriate responses, the breakdown of which is another hallmark of ageing. And they promote proliferation of stem cells that repopulate tissues with new, functional cells.
An experiment on mice suggests GLP-1 RAs may extend "healthspan"—the fraction of life during which an animal remains in good health—but did not demonstrate any extension of lifespan. In the absence of organised clinical trials, many people are taking the drugs "off-label" for longevity. Some have banded together in internet forums to monitor one another and share tips, part of a wider trend of mutual support at the fringes of pharmacology, with similar groups forming around off-label use of other peptide drugs, in effect running informal, uncontrolled trials.
You are confused; but this is your normal state.