Britons paying privately for obesity drugs are increasingly choosing Eli Lilly’s Mounjaro over Novo Nordisk’s Wegovy, online pharmacies say, in a sign the U.S. drugmaker is gaining ground on its European rival.
Mounjaro is appealing to people because of its greater efficacy, six online pharmacies and two patients told Reuters, showing Novo’s first-mover advantage is being challenged in the UK even though some pharmacies sell starter doses for the weekly injection for up to 40% more than Wegovy.
“Mounjaro is now vastly outstripping Wegovy,” said Chemist4U CEO James O’Loan, who said for the past three to four months, Mounjaro has won about 70% of its sales.
Chemist4U and another online seller, Simple Online Pharmacy, estimate that as many as 500,000 people in the UK currently take either Mounjaro or Wegovy via prescriptions from private online pharmacies
Mounjaro, unlike Wegovy, is not available through the state-run National Health Service (NHS) though it likely will be next year. Wegovy is only available through the NHS at specialist obesity clinics and in limited circumstances.
There is no public data on prescription numbers but the government said last year it had capacity to treat about 35,000 patients.
Lilly’s Mounjaro launched in the UK in February, among the first markets outside the U.S. for the drugmaker and one of only a handful of countries where it competes directly with its rival from Novo.
Wegovy has been available since September 2023 in the UK, where about two-thirds of adults are overweight or obese, according to government statistics.
Analysts estimate the obesity drug market could be worth as much as $150 billion globally per year in the next decade. The UK is one of the more populous European markets where both Wegovy and Mounjaro have launched.
O’Loan said his pharmacy is selling about 40,000 pens of Mounjaro and Wegovy combined each month, each pen roughly a month’s supply. All of the pharmacies interviewed said both medicines have been readily available since the summer, after a period of shortages ended.
One-month starter doses of Wegovy sold online cost from 109 pounds ($138.8) and 115 pounds for Mounjaro, websites showed.
Novo’s leading position in the market and ferocious demand helped make it Europe’s biggest company by market capitalisation last year. It is now worth $496 billion, but has lost about 16% of its value since peaking in June as competition with Lilly increases.
Lilly is also gaining ground on Novo in the U.S. market, according to weekly prescription data from research firm IQVIA. In the week ending Nov. 29, Novo sold nearly 200,000 prescriptions while Lilly sold more than 176,000 prescriptions.
Its fast pace of growth has boosted Lilly’s shares this year by around 37%, outperforming Novo’s which are up 12%.
Underpinning the growth in the UK, according to pharmacies and patients, is clinical trial data from before the drugs were respectively approved that showed Wegovy helped people lose on average 15% of their body weight, compared with the nearly 23% achieved by Mounjaro when combined with a healthy diet and exercise.
Data published last week from a more recent study that compared the two drugs directly showed for the first time that when trial parameters are the same, Lilly’s drug is more effective for weight loss than Wegovy.
Novo declined to comment on UK sales and said prescribing decisions should be based on what is most appropriate for individual needs. Eli Lilly declined to comment.
DRUG SWITCHING
Alan, a 54-year-old who works in financial services and agreed to be quoted by his first name, made the switch to Mounjaro in March having taken Wegovy since October 2023.
The Londoner was worried his weight loss might plateau, because he would need to start on the lowest dose strength and build up to stronger doses, a similar procedure to Wegovy.
But he lost a kilo (2.2 pounds) in his first month, more than the amount he had shed on the highest dose of Wegovy before changing.
“Efficacy drove my switch,” he told Reuters. “It was a no-brainer, it seemed the obvious thing to try.”
Juniper pharmacy’s clinical director Matt Vickers said between 70% and 80% of its new customers are starting out on Mounjaro.
UK pharmacy chain Superdrug said it filled three times as many prescriptions for Mounjaro as for Wegovy in October while online pharmacy MedExpress said they are seeing more new customers opting for Mounjaro than Wegovy.
John, who asked to be identified by his middle name, told Reuters in November last year he had shed 18 kg using Novo’s diabetes drug Ozempic, which contains the same active ingredient as Wegovy.
He went on to beat his target to lose another 20 kg but still plans to switch to Mounjaro in January, he said.