Novo Nordisk's Wegovy has effectively ceded its lead in Korea's obesity drug market to Eli Lilly's Mounjaro. With the tide of the glucagon-like peptide (GLP)-1 obesity drug market having shifted decisively toward Mounjaro, and with the launch of the first domestically developed drug expected within the year, attention is focused on whether the cornered Wegovy will cut its prices further.
According to Drug Utilization Review (DUR) data obtained from the Health Insurance Review and Assessment Service by Rep. Nam In-soon of the Democratic Party, a member of the National Assembly's Health and Welfare Committee, on the 29th, Mounjaro's lowest dose (2.5mg) was prescribed 142,434 times last month alone, about 19.6 times more than Wegovy's lowest dose (0.25mg). These figures represent cases in which clinics and hospitals completed prescription reviews through DUR to prevent duplicate prescriptions. Because the exact prescription volume cannot be tallied given the nature of non-reimbursed drugs, prescription trends and market changes for each product can be examined through DUR review records. Both products are self-injected once weekly, starting at the lowest dose and gradually increasing based on the patient's treatment response and tolerability. Lowest-dose prescription volume is the most direct indicator of the flow of new patients.
The gap in total prescription volume across all doses is also widening. Mounjaro prescriptions rose about 18-fold, from 18,579 in August last year, its first month on the market, to 335,306 in June this year. With demand surging immediately after launch, Mounjaro surpassed Wegovy's total prescription count within four months. As of June, Mounjaro's total prescriptions stood at 5.1 times Wegovy's (65,410).
As of June, the lowest dose accounted for 42.5% of Mounjaro's total prescriptions. Prescriptions in the increase and maintenance stages are also steadily rising, with 134,900 for 5mg, 30,850 for 7.5mg, and 26,805 for 10mg, while additional supply of high-dose products (12.5mg and 15mg) began last month. Observers in the market say that with new patient inflows and dose increases for existing patients proceeding simultaneously, Mounjaro's strong growth is likely to continue for the time being.
By contrast, Wegovy, launched in October 2024, effectively monopolized the domestic market and peaked at 88,895 prescriptions in May last year, but appears to have completely surrendered its lead this year. Novo Nordisk went all out to defend its market share ahead of the competitor's launch. Departing from its strategy of supplying all Wegovy doses at a uniform price in the 370,000 won range for a four-week supply, the company readjusted prices by dose, dropping the lowest-dose supply price by 42% to the 200,000 won range. From October last year, it began co-marketing with Chong Kun Dang, which has experience selling obesity treatments and a nationwide clinic-level sales network. Still, it failed to reverse the market's shift toward the competing drug.
The industry views this as a reflection of demand from consumers who want powerful weight-loss effects even at a higher cost. According to the results of a Phase 3b clinical trial that directly compared the two drugs, the group receiving the maximum tolerated dose of Mounjaro lost an average of 20.2% of their body weight over 72 weeks, while the weight-loss rate for the group receiving the maximum dose of Wegovy was only 13.7%. Although the study did not compare each dose individually, the medical community commonly assesses that the difference in weight-loss effects perceived by consumers is having a significant impact on product choice.
The market is watching whether Novo Nordisk will implement further price cuts. Mounjaro becomes more of a cost burden than Wegovy as the dose increases. The view is that Wegovy could defend its market by lowering supply prices in the increase and maintenance stages, which patients use over long periods. The imminent commercialization of 'Efe', a GLP-1 obesity drug developed by Hanmi Pharmaceutical (128940), is cited as another variable that will pressure Wegovy's price. Hanmi Pharmaceutical applied for domestic product approval of Efe in December last year, and having been designated for the Ministry of Food and Drug Safety's fast-track review for global innovative products, it is expected to be approved as early as October. In a Phase 3 clinical trial involving 448 obese Korean adults, Efe showed an average weight-loss rate of 9.75% at 40 weeks, far ahead of the placebo group (0.95%). The industry believes that Efe, which has its own production base and domestic sales network, is highly likely to be launched at a price similar to or slightly lower than Wegovy.
However, Novo Nordisk said, "We are making multifaceted efforts to improve access for patients who cannot receive the drug due to morbid obesity or financial issues, but nothing has been decided regarding pricing policy."
