What Is Lenbelintide (AZD6234)? The Amylin Peptide Now in Phase 3 — Alone and Added to Incretins

The amylin field has moved quickly from early experimental research into large late-stage clinical programmes.

One of the newest compounds to make that transition is:

lenbelintide, previously known as AZD6234.

Developed by AstraZeneca, lenbelintide is an investigational amylin-receptor peptide being studied for chronic weight management.

What makes it especially interesting is the way AstraZeneca is developing it.

Lenbelintide is now being studied:

• as a standalone amylin-based therapy
• in people with type 2 diabetes
• and as an add-on to existing incretin therapies

That last programme is particularly important because it directly tests one of the biggest emerging ideas in metabolic medicine:

Can amylin add further benefit after GLP-1 or other incretin therapy has already been established? (AstraZeneca Clinical Trials⁠)

What Is Lenbelintide?

Lenbelintide is the generic name now used for the compound previously known by the development code:

AZD6234

It is a peptide designed to act through the amylin receptor system.

Amylin is a naturally occurring pancreatic peptide released alongside insulin after meals.

Its biological effects include:

• increasing satiety
• reducing food intake
• promoting meal termination
• slowing gastric emptying
• influencing post-meal glucagon signalling

Modern amylin drugs attempt to reproduce these effects while remaining active long enough for practical once-weekly treatment.

Is Lenbelintide a GLP-1 Drug?

No.

This is one of the important differences.

Lenbelintide targets the amylin pathway, rather than being another standalone GLP-1 receptor agonist.

That puts it in the same broad research family as compounds such as:

• cagrilintide
• petrelintide
• ABBV-295

although each compound has its own pharmacology and clinical programme.

A 2026 review of emerging amylin drugs specifically included AZD6234 among the new long-acting amylin-based therapies being developed for obesity. (PubMed⁠)

Why Is Amylin Attractive as a Separate Pathway?

GLP-1 has already shown that appetite-regulating peptide biology can produce substantial changes in body weight.

But GLP-1 is not the only satiety signal.

Amylin contributes to meal regulation through partly different neural pathways.

That creates two possibilities:

amylin can potentially work independently

and

amylin can potentially complement incretin drugs.

Lenbelintide is now being developed to investigate both.

How Far Has Lenbelintide Progressed?

Quite far.

AstraZeneca’s July 2026 pipeline listed AZD6234 in Phase 2 for chronic weight management.

Since then, several Phase 3 SELENE trials have begun. (AstraZeneca⁠)

This rapid progression makes lenbelintide one of the more advanced emerging amylin programmes.

What Is SELENE 1?

SELENE 1 is a large Phase 3 study evaluating lenbelintide in adults with obesity or overweight and at least one weight-related condition who do not have type 2 diabetes.

AstraZeneca plans to enrol approximately:

2,500 participants.

Participants receive once-weekly subcutaneous lenbelintide or placebo.

The study is examining percentage change in body weight after extended treatment. (AstraZeneca Clinical Trials⁠)

The trial began in August 2026.

What Is SELENE 2?

SELENE 2 focuses on people who have:

• overweight or obesity
• and type 2 diabetes

The trial plans to enrol approximately:

1,500 participants.

It compares lenbelintide with placebo and evaluates body-weight change over 68 weeks, alongside safety and metabolic outcomes. (AstraZeneca Clinical Trials⁠)

This is important because weight-loss responses can differ considerably between populations with and without type 2 diabetes.

What Is SELENE 3?

SELENE 3 may be the most interesting study in the programme.

Instead of testing lenbelintide alone, researchers are adding it to existing incretin-based therapy.

Participants are already receiving an incretin treatment and then receive:

• lenbelintide
• or placebo

on top of that treatment.

Approximately 500 participants are planned. (AstraZeneca Clinical Trials⁠)

This directly tests the idea of amylin as an add-on pathway.

Why Is SELENE 3 So Important?

Because it asks a question with major implications for the future of metabolic treatment:

What happens when someone already receiving an incretin therapy adds amylin signalling?

This is conceptually similar to several other emerging programmes.

For example:

CagriSema

combines cagrilintide with semaglutide.

EloraTZP

combines eloralintide with tirzepatide.

Petrelintide + CT-388

combines amylin with GIP/GLP-1 activity.

Lenbelintide’s programme therefore contributes to a wider industry-wide effort to establish whether amylin becomes the natural partner to incretin therapy.

Does “Incretin-Based Therapy” Mean Only Semaglutide?

No.

The Phase 3 programme is described broadly as adding lenbelintide to stable incretin-based medications. (AstraZeneca Clinical Trials⁠)

The trial therefore addresses the general concept of adding amylin to established incretin treatment rather than being presented simply as a fixed lenbelintide-semiglutide product.

This makes the programme scientifically different from CagriSema.

Could This Tell Us Something About Reta+?

Potentially.

Retatrutide itself provides:

• GLP-1
• GIP
• glucagon

Recent preclinical research suggests that adding an amylin analogue such as cagrilintide can further change metabolic effects.

Lenbelintide is not cagrilintide, and there is no basis for assuming the compounds behave identically.

But SELENE 3 addresses an important part of the same larger question:

Can adding amylin meaningfully extend the effect of an already-active incretin therapy?

That makes its results highly relevant to the broader “Reta+” research concept.

What Did Earlier Lenbelintide Studies Look Like?

Before Phase 3, AZD6234 underwent Phase 1 and Phase 2 development.

A completed Phase 1 repeat-dose trial enrolled 104 participants with overweight or obesity and examined:

• safety
• tolerability
• pharmacokinetics
• pharmacodynamic effects

The study began in November 2023 and was completed in March 2026. (AstraZeneca Clinical Trials⁠)

What About Phase 2?

A Phase 2b study investigated once-weekly AZD6234 in adults with obesity or overweight and weight-related conditions.

The study used body-weight change as a key outcome.

A separate Phase 2 programme also investigated AZD6234 alongside another AstraZeneca metabolic compound, AZD9550. (AstraZeneca Clinical Trials⁠)

Public numerical results from those completed Phase 2 trials remain limited compared with the detailed datasets available for compounds such as petrelintide or cagrilintide.

That is important to state clearly.

If Phase 2 Results Aren’t Fully Public, Why Has It Reached Phase 3?

Drug developers can make progression decisions using their complete internal clinical datasets before every numerical result appears in peer-reviewed publications or trial registries.

AstraZeneca has evidently seen enough information to move lenbelintide into several large Phase 3 programmes.

But from an independent research perspective, the absence of detailed public Phase 2 numbers means caution is still necessary when comparing its effectiveness with other amylin drugs.

Is That a Limitation?

Yes.

For compounds such as petrelintide, there are now peer-reviewed percentage weight-loss results.

For lenbelintide, the strongest publicly verifiable information currently concerns:

• trial design
• phase of development
• participant numbers
• combination strategy

rather than a complete published efficacy dataset.

That makes statements such as “lenbelintide is better than cagrilintide” or “better than petrelintide” premature.

How Is Lenbelintide Different From Petrelintide?

Both target amylin biology.

Petrelintide has published Phase 2 efficacy data and has progressed into Phase 3.

Lenbelintide has also entered Phase 3, but its programme places particularly strong emphasis on add-on treatment to incretins.

This makes lenbelintide especially interesting as a combination platform.

How Is Lenbelintide Different From Cagrilintide?

Cagrilintide’s most prominent clinical programme combines it directly with semaglutide as:

CagriSema.

Lenbelintide’s Phase 3 strategy is broader.

AstraZeneca is testing it:

• alone
• in people with diabetes
• and added to established incretin treatment.

This may ultimately provide useful information about whether amylin therapy can be layered onto different metabolic treatments rather than being tied to one fixed combination.

How Is Lenbelintide Different From Eloralintide?

Eloralintide is designed as a selective AMY1 receptor agonist.

Lenbelintide is generally described as an amylin-receptor peptide.

That represents another example of competing philosophies within amylin research:

broader amylin agonism

versus

selective receptor targeting.

Human clinical outcomes will ultimately determine whether either approach offers meaningful advantages.

What About ABBV-295?

ABBV-295 is another newer amylin analogue.

Its early programme has attracted attention partly because of its very long duration and the possibility of less-frequent administration.

Lenbelintide’s standout feature is different.

It is already being tested in very large Phase 3 studies and specifically as an adjunct to incretin therapy.

Is Lenbelintide Being Studied With Other AstraZeneca Drugs?

Yes.

AstraZeneca’s pipeline also lists:

AZD9550 + AZD6234

for obesity research. (AstraZeneca⁠)

A completed Phase 2 ASCEND study investigated AZD6234 alone and in combination with AZD9550.

That suggests AstraZeneca is exploring lenbelintide not simply as a standalone product but as part of a broader metabolic combination strategy. (AssetMemo⁠)

What Is AZD9550?

AZD9550 is another experimental metabolic compound from AstraZeneca.

Its combination with lenbelintide reinforces a growing trend:

pharmaceutical companies increasingly appear to view amylin as a foundation or partner mechanism rather than a single isolated treatment.

As with other experimental combinations, conclusions should wait for full clinical results.

Why Are So Many Companies Adding Amylin to Incretins?

Because incretin therapies can already produce strong effects.

The next challenge is not necessarily replacing them.

It may be finding another pathway that adds something meaningful without simply increasing GLP-1 exposure.

Amylin is particularly attractive because it contributes independently to:

• fullness
• meal termination
• food intake
• gastric signalling

This gives it a strong biological rationale as a complementary pathway.

Could Add-On Amylin Help When Weight Loss Plateaus?

This is a very interesting research question, but it is not yet established.

In real-world treatment, body weight often eventually reaches a plateau.

One potential future strategy could be:

maintain the existing incretin

and

add another complementary pathway.

SELENE 3 may provide valuable information about whether that approach actually produces additional weight reduction.

Could It Allow Lower Incretin Doses?

Potentially.

Combination therapy does not necessarily have to mean maximum doses of every drug.

One possible future strategy could involve combining lower doses of different pathways to achieve a useful effect with better tolerability.

This principle is well established in many other areas of pharmacology.

But lenbelintide trials will need to determine whether it applies to amylin/incretin therapy.

What About Gastrointestinal Side Effects?

Amylin and incretin therapies can both affect:

• appetite
• gastric emptying
• gastrointestinal function

So combination treatment could potentially increase gastrointestinal adverse effects.

Large Phase 3 trials are essential because they can establish whether additional efficacy is accompanied by acceptable tolerability.

This balance may ultimately be just as important as absolute weight reduction.

Is Lenbelintide Approved?

No.

Lenbelintide remains investigational.

It is currently being studied in Phase 3 trials and has not yet been established as an approved routine treatment.

SELENE 1 and SELENE 2 have estimated primary completion dates in 2028, meaning important definitive data are still ahead. (AstraZeneca Clinical Trials⁠)

Why Is Lenbelintide Worth Watching?

Because it represents several major trends in one programme:

amylin as a standalone metabolic pathway

amylin combined with incretin therapy

and

large Phase 3 testing of the add-on strategy.

Rather than asking only whether amylin works, AstraZeneca is effectively asking:

Where does amylin fit within an increasingly complex treatment ecosystem?

The Bigger Picture

The amylin field now includes several different strategies:

Cagrilintide
→ amylin analogue + semaglutide.

Petrelintide
→ amylin monotherapy + future combination strategies.

Eloralintide
→ selective AMY1 agonism + tirzepatide.

ABBV-295
→ long-duration amylin monotherapy.

Lenbelintide
→ amylin monotherapy + add-on incretin therapy.

This competition is useful because it should reveal whether amylin is best used:

• alone
• in fixed combinations
• sequentially
• or added after another therapy has already been established.

The Bottom Line

Lenbelintide, formerly known as AZD6234, is an investigational amylin-receptor peptide being developed by AstraZeneca for chronic weight management.

It has now moved into a substantial Phase 3 SELENE programme.

SELENE 1 plans to study approximately 2,500 people without type 2 diabetes, while SELENE 2 plans around 1,500 participants with type 2 diabetes. (AstraZeneca Clinical Trials⁠)

Most interestingly, SELENE 3 is testing lenbelintide as an add-on to existing incretin-based treatment in around 500 participants. (AstraZeneca Clinical Trials⁠)

That makes lenbelintide particularly relevant to one of the biggest emerging questions in peptide research:

Does amylin become the next pathway added on top of GLP-1, GIP/GLP-1 and eventually other multi-receptor therapies?

The full efficacy picture is not yet public, and comparisons with cagrilintide, petrelintide or eloralintide would therefore be premature.

But its rapid move into Phase 3 — especially the dedicated incretin add-on trial — makes lenbelintide one of the amylin programmes worth watching most closely.

This article is for research and educational purposes only. Lenbelintide remains investigational and has not been established as an approved treatment.