EloraTZP is an investigational combination product that pairs tirzepatide — the active ingredient in Mounjaro — with a separate compound aimed at reducing gastrointestinal side effects. Developed by Elorac Pharma, it is currently in clinical trials and is not approved or available in the UK. Significant Phase 2 results are expected later in 2025, and this article will be updated when that data is published.
If you follow emerging weight-loss medicines, there is another name worth knowing: EloraTZP.
Eli Lilly revealed new information about the investigational treatment on 15 September 2026, ahead of the European Association for the Study of Diabetes (EASD) annual meeting later this month.
EloraTZP combines eloralintide, Lilly’s investigational selective amylin receptor agonist, with tirzepatide, the GIP and GLP-1 receptor agonist already used in Mounjaro.
And the first results have attracted attention.
In an early Phase 1 study, Lilly reported average weight loss of 17% after 16 weeks when eloralintide was added to tirzepatide, compared with 10% with tirzepatide alone, using the trial’s efficacy estimand.
Those are striking numbers for a relatively short study.
But they are also early-stage results, and much more important Phase 2 data is coming on 30 September 2026.
Here’s what we know so far — and what we don’t.
What Is EloraTZP?
EloraTZP is an investigational treatment being developed by Eli Lilly.
It combines two Lilly medicines currently at very different stages of development:
Tirzepatide is the active ingredient in Mounjaro. It activates the GIP and GLP-1 receptors and is already authorised in the UK for type 2 diabetes and weight management in appropriate patients.
Eloralintide, also known as LY3841136, is an investigational selective amylin receptor agonist being developed by Lilly for obesity and related conditions.
Eloralintide is not currently an approved weight-loss medicine.
By combining them, Lilly describes EloraTZP as an investigational triple-acting medicine, bringing together selective amylin receptor agonism with GIP and GLP-1 receptor agonism.
That makes EloraTZP different from simply giving a higher dose of Mounjaro.
It introduces another hormonal pathway into the treatment.
Why Add Eloralintide To Tirzepatide?
Amylin is a hormone normally released alongside insulin after eating and is involved in regulating satiety and food intake.
Eloralintide has been designed to selectively activate amylin receptors. Lilly says it has the potential to decrease calorie intake, likely through effects on satiety.
Tirzepatide, meanwhile, activates the GIP and GLP-1 receptors.
The scientific idea behind EloraTZP is therefore to combine amylin, GIP and GLP-1 receptor activity within one investigational treatment strategy.
It is part of a wider pharmaceutical effort to determine whether targeting additional metabolic pathways can produce further improvements in obesity treatment beyond today’s GLP-1-based medicines.
But whether that translates into substantially better long-term weight loss, tolerability or health outcomes still needs to be demonstrated in larger and longer clinical trials.
What Did The EloraTZP Phase 1 Trial Find?
The figure attracting attention from Lilly’s latest announcement is 17% average weight loss in 16 weeks.
According to Lilly, participants receiving eloralintide 3 mg added to tirzepatide 5 mg achieved average weight reduction of approximately 17% at 16 weeks, compared with approximately 10% among participants receiving tirzepatide 5 mg alone, under the efficacy estimand.
That is a substantial difference.
However, it needs some important context.
This was Phase 1 research.
Phase 1 studies are early clinical studies intended primarily to investigate areas such as safety, tolerability and how a treatment behaves in humans. They involve far fewer participants and much shorter follow-up than the large Phase 3 trials used to establish the benefits and risks of medicines intended for widespread clinical use.
Sixteen weeks is also a very short period compared with modern obesity trials that frequently follow participants for a year or longer.
So the result should be viewed as a promising early signal, not evidence that EloraTZP has already been established as more effective than Mounjaro.
Does 17% Weight Loss Mean EloraTZP Is Better Than Mounjaro?
No such conclusion can currently be made.
It is tempting to compare the 17% figure with results from Mounjaro, Wegovy or even investigational Retatrutide trials, but doing so directly would be misleading.
Different trials involve different:
- participant populations
- treatment durations
- doses
- study designs
- statistical methods
- discontinuation rules
The 17% EloraTZP result was reported after only 16 weeks in early Phase 1 research.
It therefore cannot simply be placed alongside weight-loss percentages from much larger Phase 3 trials lasting 72, 80 or more weeks and treated as a like-for-like comparison.
What the result does provide is enough of a signal to make the next stage of the programme particularly interesting.
What Happens On 30 September?
This is the date to watch.
Lilly says it will present Phase 2 EloraTZP results at EASD on 30 September 2026.
The Phase 2 study involves adults with overweight or obesity and type 2 diabetes.
That population matters when interpreting whatever results emerge.
The presentation should give us substantially more information about how the combination performs beyond the small early-stage study now attracting attention.
We will update this article when those results are released.
How Is EloraTZP Different From Eloralintide?
This distinction is going to become increasingly important as the names start appearing online.
Eloralintide is the investigational selective amylin receptor agonist itself.
EloraTZP refers to Lilly’s investigational approach combining eloralintide with tirzepatide.
They aren’t interchangeable names for the same treatment.
The Peptide Brief recently covered Eloralintide and why it is beginning to attract attention after the compound started appearing in weight-loss community discussions.
EloraTZP now adds another dimension to that story because Lilly is investigating whether the amylin mechanism can complement the established GIP/GLP-1 activity of tirzepatide.
Editor’s note: Replace the link above with the exact URL of our Eloralintide UK article before publishing.
Is EloraTZP The Same As Mounjaro?
No.
Mounjaro contains tirzepatide alone.
EloraTZP combines tirzepatide with eloralintide as part of an investigational clinical programme.
Mounjaro is an authorised medicine in the UK and can be prescribed to eligible patients.
EloraTZP remains experimental.
You can read our Mounjaro UK guide for more information about the treatment that is currently available through regulated UK healthcare providers.
What About Retatrutide?
EloraTZP also shouldn’t be confused with Retatrutide.
Although both involve three hormonal targets, they achieve that in different ways.
Retatrutide is a single investigational molecule designed to activate the GIP, GLP-1 and glucagon receptors.
EloraTZP combines the selective amylin receptor agonist eloralintide with tirzepatide’s GIP and GLP-1 receptor activity.
So the third pathway differs:
Retatrutide: GIP + GLP-1 + glucagon
EloraTZP: amylin + GIP + GLP-1
Both remain investigational.
Our Retatrutide UK guide tracks the development and UK status of Retatrutide separately.
Interestingly, Lilly’s EASD announcement also contains new Phase 3 Retatrutide data, so the company’s obesity pipeline is developing on several fronts simultaneously.
Is EloraTZP Available In The UK?
No.
EloraTZP is an investigational treatment being studied in clinical trials. It is not an approved UK weight-loss medicine and there is no commercially authorised EloraTZP product available from UK pharmacies.
The same distinction applies to eloralintide itself.
This is particularly important because individual research compounds sometimes begin appearing through unregulated online sellers long before the pharmaceutical treatment being studied has received regulatory approval.
Obtaining separately sourced products labelled “eloralintide” and “tirzepatide” would not be equivalent to participating in Lilly’s EloraTZP clinical programme.
The clinical trials use controlled pharmaceutical products, defined protocols and medical monitoring.
What Do We Still Not Know?
Quite a lot.
The Phase 1 result gives researchers an encouraging signal, but it does not answer many of the questions that matter if EloraTZP is eventually to become a widely used obesity treatment.
We still need substantially more evidence about:
- longer-term weight loss
- safety and tolerability
- treatment discontinuation
- gastrointestinal and other adverse effects
- metabolic outcomes
- how different doses perform
- whether benefits are maintained over longer periods
- how the combination compares with established treatments in appropriately designed trials
And ultimately, positive Phase 2 results would still not make EloraTZP an approved medicine.
Later-stage clinical development and regulatory review would be required before it could become a routine treatment.
Why EloraTZP Is Worth Watching
EloraTZP is interesting because it gives us another indication of where obesity medicine may be heading next.
The first generation of modern treatments demonstrated what targeting GLP-1 could achieve.
Tirzepatide added GIP receptor activity.
Retatrutide is investigating the addition of glucagon receptor agonism.
EloraTZP is exploring a different route by adding selective amylin receptor activity to tirzepatide.
The early 17% result makes that approach scientifically interesting.
It does not establish that EloraTZP is the next Mounjaro, that it will ultimately reach the market, or that it will outperform existing treatments.
The next meaningful evidence arrives very soon.
On 30 September, Lilly is due to present the Phase 2 results.
We’ll update this article when those data are available.
Frequently Asked Questions
What is EloraTZP?
EloraTZP is Eli Lilly’s investigational combination of eloralintide and tirzepatide. It combines selective amylin receptor agonism with the GIP and GLP-1 receptor activity of tirzepatide.
How much weight did people lose with EloraTZP?
Lilly reported that participants receiving eloralintide 3 mg added to tirzepatide 5 mg experienced approximately 17% average weight reduction after 16 weeks, compared with approximately 10% with tirzepatide 5 mg alone, using the efficacy estimand.
These are early Phase 1 results and should not be interpreted as establishing the long-term effectiveness of EloraTZP.
Is EloraTZP better than Mounjaro?
We don’t currently know.
The available EloraTZP result comes from early Phase 1 research and cannot be directly compared with the much larger and longer clinical-trial programme supporting Mounjaro.
Is EloraTZP available in the UK?
No. EloraTZP remains investigational and is not an authorised UK weight-loss treatment.
Is EloraTZP the same as Eloralintide?
No. Eloralintide is Lilly’s investigational selective amylin receptor agonist. EloraTZP combines eloralintide with tirzepatide.
When are the EloraTZP Phase 2 results coming?
Lilly says Phase 2 EloraTZP data will be presented at the European Association for the Study of Diabetes annual meeting on 30 September 2026.
Further Reading
For more background on the new amylin medicine at the centre of this combination, read our Eloralintide UK guide.
Our Mounjaro UK guide explains the tirzepatide treatment already authorised in Britain.
And our Retatrutide UK guide follows Lilly’s other major investigational obesity treatment.
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This article is for information purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any treatment. Information correct at time of publication. The Peptide Brief updates articles when guidance changes.
