The non-peptide oral GLP-1 drug orforglipron lowered blood sugar significantly more than oral semaglutide over one year, but caused more GI side effects and higher pulse rates.
-1.91% HbA1c reductionOrforglipron 36 mg lowered HbA1c nearly two full percentage points from baseline — significantly more than the -1.47% seen with the highest dose of oral semaglutide
What the researchers found
In a 52-week phase 3 trial of 1,698 adults with type 2 diabetes, oral orforglipron was not only non-inferior but statistically superior to oral semaglutide at lowering blood sugar. Orforglipron 36 mg reduced HbA1c by 1.91% from baseline vs. 1.47% for semaglutide 14 mg (treatment difference -0.44%, p<0.0001). Even the lower 12 mg orforglipron dose beat the higher semaglutide 14 mg dose (-0.24% difference, p=0.005).
However, orforglipron came with trade-offs: higher rates of gastrointestinal side effects (58-59% vs. 37-45%), more treatment discontinuations due to adverse events (9-10% vs. 4-5%), and a greater increase in pulse rate (3.7-4.7 bpm vs. 1.0-1.5 bpm).
Why it matters
Orforglipron is the first non-peptide oral GLP-1 receptor agonist — meaning it's a small molecule, not a peptide, and doesn't need the special absorption-enhancing formulation that oral semaglutide requires. Patients can take it without food or water restrictions. This head-to-head victory over oral semaglutide on blood sugar control positions orforglipron as a potentially transformative option, though the higher side effect burden will be a key factor in clinical adoption.
The numbers in context
n=1,698 · 52 weeks · HbA1c reduction: orforglipron 36mg -1.91% vs semaglutide 14mg -1.47% · Treatment difference -0.44% (p<0.0001) · GI events: 58-59% orforglipron vs 37-45% semaglutide · Discontinuation: 9-10% vs 4-5% · Pulse increase: 3.7-4.7 bpm vs 1.0-1.5 bpm
How the study worked
52-week, randomized, open-label, active-controlled phase 3 trial across 131 centers in Argentina, China, Japan, Mexico, and the USA. 1,698 adults with T2D on metformin (≥1500 mg/day), HbA1c 7.0-10.5%, BMI ≥25 were randomized 1:1:1:1 to orforglipron 12 mg, orforglipron 36 mg, semaglutide 7 mg, or semaglutide 14 mg. Primary endpoint was non-inferiority of HbA1c change at week 52 with a 0.3% margin.
Who was studied
1,698 adults with type 2 diabetes inadequately controlled on metformin, mean baseline HbA1c 8.3%, BMI ≥25, from 5 countries
What this study cannot tell us
Open-label design means participants and investigators knew which drug they were taking, which could introduce bias in reporting side effects. Funded by Eli Lilly (orforglipron's manufacturer). The study compared against currently available oral semaglutide doses — higher doses of oral semaglutide now in development were not included. Four deaths occurred across groups.
How to read the evidence
This is a high-quality phase 3 randomized controlled trial published in The Lancet with a large sample size (1,698 participants) across five countries. The main limitation is its open-label design, which could affect subjective outcome reporting, though the primary endpoint (HbA1c) is an objective lab measurement.
When this study was published
Published in 2026 with the most current data available, this is the definitive head-to-head comparison of orforglipron vs. oral semaglutide in the ACHIEVE program.
The bigger picture
The GLP-1 market is dominated by injectable drugs, and the race to create effective oral alternatives is one of the biggest stories in pharmaceutical development. Orforglipron's superiority over oral semaglutide on efficacy is a major milestone, but the higher side effect rate creates a nuanced picture. If Eli Lilly can manage the tolerability issues, orforglipron could reshape the oral GLP-1 landscape.
Questions still open
- Will orforglipron's greater blood sugar reduction translate to better long-term cardiovascular and kidney outcomes compared to oral semaglutide?
- Can dose optimization or slower titration reduce orforglipron's higher gastrointestinal side effect and discontinuation rates?
- How does orforglipron compare to injectable semaglutide (Ozempic/Wegovy) rather than just the oral formulation?
Common questions
How is orforglipron different from semaglutide?
Why did more people stop taking orforglipron if it worked better?
Read the original research
Efficacy and safety of once-daily oral orforglipron compared with oral semaglutide in adults with type 2 diabetes (ACHIEVE-3): a multinational, multicentre, non-inferiority, open-label, randomised, phase 3 trial.
Lancet (London, England)
Citation
Rosenstock, Julio; Yabe, Daisuke; Cox, David; Li, Jianghao; Denning, Max; Wu, Wen-Shuo; Liu, Rong; Zhao, Youna. (2026). Efficacy and safety of once-daily oral orforglipron compared with oral semaglutide in adults with type 2 diabetes (ACHIEVE-3): a multinational, multicentre, non-inferiority, open-label, randomised, phase 3 trial.. Lancet (London, England). https://doi.org/10.1016/S0140-6736(26)00202-3