AstraZeneca's Elecoglipron Shows 11.8% Weight Loss in Phase II Trials, Advancing to Phase III

Key Findings from the SOLSTICE Trial

The SOLSTICE study involved 406 adults with type 2 diabetes and focused on glycemic control as its primary endpoint .

• HbA1c reduction: After 26 weeks, the mean change in HbA1c, a key measure of blood sugar control, ranged from a reduction of 0.91% on the 5 mg dose to 1.88% on the 75 mg dose with a fast dose-escalation schedule . The placebo group saw a reduction of just 0.15% .
• Glycemic target achievement: Among those on the 75 mg dose, 90% achieved an HbA1c level below 7% by week 26 .
• Body weight loss in diabetes patients: While the primary focus was on blood sugar, the trial also demonstrated weight loss in participants with type 2 diabetes .

Safety and Tolerability

The safety profile of elecoglipron was described by the company as consistent with the established GLP-1 receptor agonist class, with no new safety signals identified . Common side effects for this drug class typically include gastrointestinal issues like nausea.

The Competitive Landscape: A Three-Way Race

AstraZeneca's results arrive as competition in the oral weight-loss market intensifies.

Eli Lilly's Foundayo (Orforglipron)

Lilly's Foundayo is already an FDA-approved oral small-molecule GLP-1 for chronic weight management, receiving its approval on April 1, 2026 . It is approved for use with a reduced-calorie diet and increased physical activity to reduce and maintain weight long-term in adults with obesity or overweight with at least one weight-related comorbidity .

While direct cross-trial comparisons are not possible, available data points allow for a general framing of its efficacy:

• In Phase III trials, the highest dose of Foundayo produced an average weight loss of approximately 12.4% over 72 weeks in one analysis .
• A separate STAT News report cited a figure of 11.2% weight loss in its 72-week Phase III study .

This longer-term data is roughly in the same range as elecoglipron's mid-stage 11.8% result at 36 weeks. The key caveat is that Foundayo has proven its efficacy over nearly double the time period in late-stage trials, while elecoglipron's path to an FDA application is just beginning .

Novo Nordisk's Amycretin

Novo Nordisk's next-generation candidate, amycretin, is a unimolecular GLP-1 and amylin receptor co-agonist now in Phase III trials . Phase II data in adults with type 2 diabetes showed the injectable formulation delivered up to 14.5% weight loss over 36 weeks, and the oral version produced up to 10.1% weight loss . The drug has demonstrated a dose-dependent response with no observed plateau . Amycretin's dual mechanism of action could provide an efficacy advantage, but it is further from market than Foundayo and in a similar development stage to elecoglipron.

The Crucial Disclaimer on Comparisons

It is critical to note that none of these oral agents have been tested head-to-head. Elecoglipron's data is from Phase IIb, Foundayo's from Phase III post-approval studies, and amycretin's from Phase II. Differences in trial design, patient demographics, background therapy, and follow-up duration make direct efficacy comparisons unreliable .

What's Next for Elecoglipron?

AstraZeneca has confirmed that elecoglipron is advancing into a comprehensive Phase III programme, which will provide the large-scale, long-term data needed for regulatory approval . The company views the drug as a key part of a differentiated weight management portfolio that includes potential combination therapies .