Novo Nordisk says real-world analysis finds Ozempic 2 mg matches Mounjaro on glucose control and may drive more weight loss

Novo Nordisk (NVO) on Monday pointed to new real-world evidence suggesting that people with type 2 diabetes who escalate from Ozempic 1 mg to Ozempic 2 mg reach glucose control rates similar to patients who switch to Lilly’s Mounjaro (tirzepatide). Novo Nordisk also said the semaglutide dose escalation group was more likely to achieve meaningful weight loss, using an observational, retrospective claims-analysis design.

The company’s analysis, part of what Novo Nordisk calls the COMPETE SWITCH retrospective cohort study, compared adults treated with once-weekly semaglutide at 1 mg who later received semaglutide 2 mg, against adults who switched to tirzepatide after receiving semaglutide 1 mg. Novo Nordisk said the dataset included linked laboratory results within a large US claims database covering January 2018 through September 2025, and involved more than 64,000 adults for the HbA1c outcome analysis.

In the HbA1c cohort, Novo Nordisk reported that by one year, 74.7% of adults who were escalated to semaglutide 2 mg achieved HbA1c below 7%, compared with 75.1% of adults who switched to tirzepatide starting at 2.5 mg or 5 mg (with allowed titration). Novo Nordisk said the results showed comparable achievement across both groups over follow-up, with its report also noting overall statistical comparison details.

For weight outcomes, Novo Nordisk said the study found a higher likelihood of reaching weight loss of at least 5% with semaglutide 2 mg versus switching to tirzepatide. In the weight-loss cohort, Novo Nordisk reported that by one year, 60.5% of adults escalated to semaglutide 2 mg achieved at least 5% weight loss, versus 55.3% of those who switched to tirzepatide, with a P-value less than 0.001.

Novo Nordisk framed the weight result as supportive of treatment intensification within the same drug class for certain patients. The company said the tirzepatide arm included dosing flexibility, where titration could move beyond the starting doses, with about 24% of the HbA1c cohort and about 40% of the weight-loss cohort reaching tirzepatide doses higher than 5 mg, and approximately 3% to 5% reaching the 15 mg dose. Novo Nordisk also reported a hazard ratio of 1.19 for achieving at least 5% weight loss over time in favor of semaglutide dose escalation.

The announcement comes as competition between semaglutide-based therapies and tirzepatide-based therapies continues to intensify in both diabetes and weight management. Ozempic is Novo Nordisk’s once-weekly GLP-1 receptor agonist indicated for type 2 diabetes, while Mounjaro is Lilly’s once-weekly dual GIP and GLP-1 receptor agonist for improving glycemic control in adults with type 2 diabetes, with both drug classes widely viewed as central to the modern obesity and metabolic drug market.

Novo Nordisk emphasized limitations typical of retrospective claims analyses. It said results may reflect residual, unmeasured confounding, and that associations cannot be treated as definitive proof of cause and effect. The company also said retrospective claims can exclude patients with intermittent coverage or underserved populations, which may limit generalizability. Novo Nordisk further noted that while HbA1c and weight data existed for many patients, not all patients may have complete records, and it could not fully characterize factors that can affect adherence or switching decisions.

Looking ahead, Novo Nordisk said the findings will be presented at the American Diabetes Association’s 2026 Scientific Sessions on June 7 in New Orleans. For Eli Lilly and clinicians, the key question will be how payers and physicians interpret this specific dosing-and-switching comparison when weighing drug selection, titration strategy, and expected glucose and weight outcomes at the patient level.