Eli Lilly’s Phase 3 ATTAIN trials show older adults treated with Foundayo (orforglipron) achieved up to 13% weight loss at 72 weeks, with a safety profile consistent across age groups. Results presented at ECO 2026 highlight the first oral GLP‑1 therapy’s potential to improve adherence in obesity management.
Written By: Nikita Jha, BPharm
Reviewed By: Pharmacally Editorial Team
Eli Lilly and Company presented new Phase 3 findings at the 2026 European Congress on Obesity (ECO) in Istanbul showing that adults aged 65 years and older treated with Foundayo (orforglipron) achieved clinically meaningful weight loss. Post‑hoc analyses from the ATTAIN‑1 (NCT05869903) and ATTAIN‑2 (NCT05872620) trials demonstrated statistically significant reductions in body weight at 72 weeks across all tested doses compared with placebo (p<0.001).
Efficacy Outcomes in ATTAIN Trials
In ATTAIN‑1, which enrolled adults with obesity or overweight without diabetes, participants ≥65 years achieved mean weight reductions of 7.9%, 11.3%, and 13.0% at the 5.5 mg, 9 mg, and 17.2 mg doses, respectively, versus 1.6% with placebo. Younger participants showed broadly comparable outcomes, underscoring consistency across age groups.
In ATTAIN‑2, which studied adults with obesity or overweight and type 2 diabetes, older participants achieved mean reductions of 7.5%, 8.3%, and 12.2% across escalating dose groups compared with 2.3% for placebo. Investigators reported that older adults without diabetes achieved up to 13% mean weight reduction at the highest dose, a magnitude considered clinically meaningful in obesity management.
Safety Profile in Older Adults
Gastrointestinal adverse events including nausea, diarrhea, constipation, and vomiting remained the most common side effects, consistent with the GLP‑1 drug class. Serious adverse events occurred more frequently among older participants than younger patients, though rates were generally similar between treatment and placebo groups. Lilly reported that the safety profile in older adults was broadly consistent with the overall trial populations, without new safety findings related to frailty or muscle loss emerging in the analysis.
Oral GLP‑1 Innovation
Foundayo is the first approved oral GLP‑1 receptor agonist that patients can take without food or water restrictions. Unlike injectable GLP‑1 therapies, the small‑molecule pill offers flexible daily dosing, which may improve adherence in older patients managing obesity and related comorbidities.
Rachel Batterham, senior vice president of medical innovation and external engagement at Lilly Cardiometabolic Health, said the results support the potential role of a flexible oral GLP‑1 therapy in older adults who may prefer pills over injectable medicines. External investigators at ECO also emphasized the importance of oral GLP‑1 options for older populations where adherence and tolerability remain critical.
Broader ATTAIN Program
The ATTAIN program continues to evaluate orforglipron across obesity‑related conditions including type 2 diabetes, obstructive sleep apnea, osteoarthritis knee pain, hypertension, peripheral artery disease, and stress urinary incontinence. Lilly is expected to pursue additional regulatory submissions and lifecycle expansion opportunities as the broader clinical program advances. Because the findings come from a post hoc subgroup analysis, the results should be considered exploratory and will require confirmation in prospective studies.
Reference
About the Writer
Nikita Jha, BPharm (LinkedIn) a pharmacy graduate specializing in medical writing, with a strong ability to interpret complex medical and regulatory information and translate it into clear, accurate, and evidence-based healthcare content. Known for her attention to detail and precision, she focuses on delivering high-quality scientific communication that supports drug safety and informed decision-making