Shares of Eli Lilly and Company (NYSE: LLY) moved higher after the pharmaceutical company reported strong Phase 2b trial results for its experimental obesity and type 2 diabetes treatment.
Eli Lilly stock rose as much as 2.6% before trimming gains to around 0.5%. Meanwhile, shares of rival Novo Nordisk slipped about 0.3% following the announcement.
EloraTZP Delivers 23.3% Average Weight Loss
The experimental therapy, known as EloraTZP, combines eloralintide with tirzepatide.
In a 48-week study involving 367 participants, the combination produced average weight loss of up to 54.1 pounds, or 23.3%.
That result was significantly higher than the 34.4-pound, or 14.8%, reduction achieved with a 15 mg dose of tirzepatide alone.
The combination also delivered stronger blood sugar control.
Participants receiving EloraTZP recorded average A1C reductions of up to 2.9%. By comparison, tirzepatide alone lowered A1C by around 2.4%.
How Eli Lilly’s Drug Combination Works
EloraTZP is designed to target three hormone pathways linked to appetite, metabolism, and blood sugar control.
The treatment combines eloralintide, a selective amylin receptor agonist, with tirzepatide.
Tirzepatide works as a dual GIP and GLP-1 receptor agonist.
Together, the drugs are designed to activate GIP, GLP-1, and amylin pathways at the same time.
This multi-hormone approach could potentially improve both weight reduction and glucose control compared with existing treatments.
Highest Dose Produced the Strongest Results
The Phase 2b study met all of its primary and secondary endpoints across the tested dose combinations.
The strongest results came from the highest dose tested.
Participants receiving 9 mg of eloralintide combined with 15 mg of tirzepatide experienced the largest reductions in both body weight and A1C.
At the beginning of the study, participants had an average body weight of 232.4 pounds and an average A1C level of 8.1%.
EloraTZP Outperformed Each Drug on Its Own
The trial also provided a comparison between the combination and its individual components.
Eloralintide alone reduced body weight by up to 28.6 pounds, or 12.3%.
It also lowered A1C by around 1.4%.
Tirzepatide alone produced average weight loss of 34.4 pounds, or 14.8%, while reducing A1C by approximately 2.4%.
The EloraTZP combination exceeded both of those results.
Side Effects Remain an Important Factor
The most common adverse events reported during the trial were gastrointestinal.
Most were described as mild to moderate and occurred mainly during the dose-escalation period.
However, treatment discontinuation rates were higher among patients receiving the combination therapy.
Discontinuation rates for EloraTZP ranged from 10.8% to 27.0%.
That compares with 2.9% for tirzepatide alone and 16.7% for the placebo group.
These figures suggest that tolerability could remain an important issue as the treatment moves into larger trials.
Eli Lilly Plans Phase 3 Trials in Late 2026
The results were presented at the 62nd Annual Meeting of the European Association for the Study of Diabetes in Milan, Italy.
Following the positive Phase 2b data, Eli Lilly plans to begin Phase 3 trials of EloraTZP in the fourth quarter of 2026.
Those studies will provide a broader test of the treatment’s effectiveness, safety, and tolerability.
Weight-Loss Drug Competition Continues to Intensify
The strong EloraTZP data adds another potential treatment to Eli Lilly’s growing obesity and diabetes pipeline.
Competition in the weight-loss drug market remains intense, particularly between Eli Lilly and Novo Nordisk.
If future trials confirm the Phase 2b results, EloraTZP could strengthen Lilly’s position in the rapidly expanding obesity-treatment market.
For investors, the next major milestone will be the start of Phase 3 testing and whether the combination can maintain its strong weight-loss results in a larger patient population.
