Investigational — not available anywhere
This compound is not approved for any use and is not currently sold by any vendor, including research-chemical and RUO (“research use only”) sellers. Everything on this page comes from the developer’s own registered trials or from published research; there is no legitimate product to buy under this name, and any listing claiming otherwise should be treated with suspicion. See the full Addiction & Mental Health Pipeline for other compounds at this same stage.
Brenipatide (LY3537031) is Eli Lilly’s investigational dual GIP/GLP-1 receptor agonist, the same receptor pairing as tirzepatide, but engineered for the brain rather than weight loss. It is a once-weekly injection now in phase 3 trials for alcohol use disorder and major depressive disorder. Phase 1 data presented in September 2026 showed no serious adverse events and gastrointestinal side effects matching placebo. It is not approved anywhere and not available outside enrolled clinical trials.
Research snapshot
| Peptide category | GIP/GLP-1 dual receptor agonist (incretin-class), positioned for CNS/psychiatric indications rather than metabolic ones |
| Primary research interest | Alcohol use disorder and major depressive disorder; secondary Phase 2 programs in opioid use disorder, tobacco use disorder, bipolar disorder, schizophrenia, asthma, IBS, COPD |
| Highest available evidence | Published Phase 1 safety/dose-finding data (conference-presented, not yet in a peer-reviewed paper as of this writing) |
| Human research available | Yes, limited — one completed Phase 1 multiple-ascending-dose study; Phase 3 trials enrolling/underway with no efficacy data published yet |
| Development status | Phase 3 (alcohol use disorder, depression); Phase 2 in several other indications |
| Regulatory status | Not approved anywhere; investigational only |
| Last reviewed | September 27, 2026 |
Technical identity
| Primary name | Brenipatide |
| Alternative names | LY3537031 (Lilly development code) |
| Peptide sequence | Not reliably established from public sources reviewed; Lilly has not published the sequence |
| Amino-acid length | Not reliably established from public sources reviewed |
| Molecular formula | Not reliably established from public sources reviewed |
| Molecular weight | Not reliably established from public sources reviewed |
| CAS Registry Number | Not reliably established |
| PubChem CID | Not reliably established |
| UNII | Not established |
| DrugBank ID | Not established |
| Chemical modifications | Described by Lilly as carrying amino-acid substitutions intended to resist the proteases that degrade GLP-1 analogs; specifics not published. Half-life 9.08-12.5 days (Phase 1 MAD study), roughly double tirzepatide’s ~5 days |
| Peptide class | Dual GIP/GLP-1 receptor agonist, same mechanism class as tirzepatide |
| Primary biological target | GIP and GLP-1 receptors, reported to be selective for reward and neuroinflammation-related circuitry rather than gut-driven satiety pathways |
| Developer or originator | Eli Lilly and Company |
| Development status | Phase 3. Note: this table is thinner than most because Lilly has not published a structure paper or registered the compound in PubChem/CAS/DrugBank as of this review |
What is brenipatide?
Brenipatide is an experimental drug from Eli Lilly, still years from any approval, built on the same GIP/GLP-1 dual-receptor mechanism as tirzepatide (Mounjaro/Zepbound). What makes it different is the target. Tirzepatide and its relatives were built to drive weight loss by acting on the gut and metabolism. Brenipatide was reportedly designed the opposite way: to act on reward and inflammation circuitry in the brain at doses far below what’s used for weight loss, while leaving the gut mostly alone.
That design choice shows up directly in the numbers. Where tirzepatide tops out around 15 mg weekly, brenipatide’s phase 1 program tested 0.3 to 4.5 mg weekly, a fraction of the dose. And where nausea and GI upset are the defining side effect of every marketed GLP-1 drug, brenipatide’s GI adverse event rate in its phase 1 trial matched placebo exactly, 25% in both arms.
Lilly presented this phase 1 data at Psych Congress 2026 in New Orleans in September 2026. The presentation covered a completed multiple-ascending-dose study (J2S-MC-GZMD, ClinicalTrials.gov NCT06606106): 212 participants, five weekly dose levels from 0.3 to 4.5 mg, three cohorts spanning BMI 22 to 45 including dedicated Japanese and Chinese cohorts.
Brenipatide skipped a weight-loss indication entirely and went straight into phase 3 for two brain-related conditions: alcohol use disorder and major depressive disorder. Behind those sit a wide net of phase 2 programs (opioid use disorder, tobacco use disorder, bipolar disorder, schizophrenia) plus separate immunology programs (asthma, irritable bowel syndrome, COPD), 13 phase 2/3 studies total as of this review. This is a large, deliberate bet by Lilly that incretin receptors do something meaningful in the brain beyond appetite, an idea that had mostly been community discussion and secondary findings from GLP-1 weight-loss trials until this program moved it into a purpose-built pharma pipeline. Lilly’s broader incretin pipeline also includes retatrutide, a triple GIP/GLP-1/glucagon receptor agonist developed for weight loss, one more sign of how central this receptor family has become across the company’s drug development beyond diabetes and obesity alone.
How does it work?
Plain-English explanation
Brenipatide activates the same two hormone receptors as tirzepatide, GIP and GLP-1, but Lilly says it was engineered to concentrate that activity in brain circuits tied to craving, mood, and inflammation rather than the gut. That is the proposed reason it can work at much lower doses without the nausea that comes with gut-targeted incretin drugs, and the proposed reason it might help with drinking behavior or depression rather than, or in addition to, weight.
Technical explanation
Brenipatide is a dual GIP/GLP-1 receptor agonist reported to carry amino-acid substitutions that resist the proteases that normally degrade native GLP-1 and GLP-1 analogs, extending its half-life to roughly 9 to 12.5 days versus tirzepatide’s approximately 5 days, according to Lilly’s phase 1 presentation. The specific mechanism connecting incretin receptor activation to reward-circuit and neuroinflammatory effects has not been published in detail as of this review; Lilly’s public materials describe intent, a molecule “designed for the brain,” more than a validated mechanistic pathway.
Potential benefits and research applications
Alcohol use disorder
Brenipatide is being investigated for reducing harmful drinking patterns in two phase 3 trials, RENEW-ALC-1 and RENEW-ALC-2 (ClinicalTrials.gov NCT07219966 and NCT07219953), roughly 2,200 participants combined across eight countries, one trial in moderate-to-severe alcohol use disorder and the other in alcohol use disorder with hazardous drinking. The primary endpoint is change in drinking pattern measured by the Timeline Followback method, a reduction-in-harm framing rather than an abstinence-only endpoint. No efficacy results exist yet; topline data is expected around 2028.
Evidence: is being investigated for (registered human trial, efficacy results not yet published). Separately, and this is context rather than evidence for brenipatide itself: a 2025 randomized, placebo-controlled human trial published in JAMA Psychiatry (Hendershot et al., PMID 39937469) found that low-dose weekly semaglutide reduced alcohol craving, drinking quantity, and heavy-drinking days over 9 weeks in adults with alcohol use disorder. A 2026 Lancet trial in alcohol use disorder with comorbid obesity reported a similar direction of effect. That is published human clinical evidence for semaglutide, a different molecule in the same broad receptor family, not for brenipatide, which has no published efficacy data of its own yet.
Major depressive disorder
Brenipatide is being investigated in a phase 3 trial, RENEW-MDD-1 (ClinicalTrials.gov NCT07412756), roughly 1,000 participants across 14 countries, testing brenipatide plus standard of care against placebo plus standard of care on time to symptom relapse. No efficacy results exist yet.
Evidence: is being investigated for (registered human trial, efficacy results not yet published).
Other indications in earlier-phase development
Lilly has phase 2 programs registered for brenipatide in opioid use disorder, tobacco use disorder, bipolar disorder, and schizophrenia, plus immunology-focused programs in asthma, irritable bowel syndrome, and COPD. These are earlier stage than the alcohol and depression programs and were not the subject of the September 2026 data release.
What dosage information circulates?
Figures in this section summarize amounts and schedules reported in published research or circulating online. Their inclusion documents what is reported and does not establish that a regimen is verified, safe, effective, or appropriate.
| Reported use or research objective | Route reported | Amount reported | Frequency reported | Reported duration | Evidence or source category |
|---|---|---|---|---|---|
| Phase 1 safety/dose-finding (healthy participants with overweight or obesity) | Subcutaneous | 0.3, 0.75, 1.5, 3, and 4.5 mg (ascending dose cohorts) | Once weekly | Multiple-ascending-dose study; duration not specified in sources reviewed | Registered human clinical trial (unpublished full results as of this review; NCT06606106) |
| Alcohol use disorder, Phase 3 (RENEW-ALC-1/2) | Subcutaneous (once weekly, consistent with Phase 1) | Specific Phase 3 dose(s) not identified in sources reviewed | Once weekly (inferred, not independently confirmed) | 56 weeks | Registered but unpublished human trial |
| Major depressive disorder, Phase 3 (RENEW-MDD-1) | Subcutaneous (once weekly, consistent with Phase 1) | Specific Phase 3 dose(s) not identified in sources reviewed | Once weekly (inferred, not independently confirmed) | Duration not specified in sources reviewed | Registered but unpublished human trial |
| Community, forum, or vendor protocol | Not applicable | Not applicable | Not applicable | Not applicable | No established or reliably sourced dosing information was identified — brenipatide is not sold anywhere; no gray-market version has been documented |
Amounts studied in human research
Phase 1 safety and dose-finding trial (J2S-MC-GZMD, NCT06606106): weekly subcutaneous doses of 0.3, 0.75, 1.5, 3, and 4.5 mg, ascending-dose cohorts, 212 participants with overweight or obesity. This is the only dosing that has been publicly reported; the specific per-arm doses used in the phase 3 alcohol use disorder and depression trials have not been independently confirmed as of this review and should be pulled directly from each trial’s ClinicalTrials.gov record before being treated as settled.
Amounts studied in animal research
Not identified in the sources reviewed for this page. Lilly’s public September 2026 presentation focused on the phase 1 human data; no animal dosing figures were located.
Practitioner and community-reported protocols
None exist. Brenipatide has never been sold or distributed outside Lilly’s clinical trial program, legitimately or gray-market. Any product marketed under the name “brenipatide” or “LY3537031” outside a Lilly-run clinical trial should be treated as counterfeit, since no legitimate or gray-market supply chain exists. This is one of the few entries on this site where the “what circulates online” question has a genuinely empty answer rather than a murky one.
What circulates E5
| Reported use | Route | Amount reported | Frequency | Reported length |
|---|---|---|---|---|
| Phase 1 safety and dose-finding (overweight/obesity, healthy participants) | Subcutaneous | 0.3, 0.75, 1.5, 3, or 4.5 mg (ascending dose cohorts) | Once weekly | Multiple-ascending-dose study |
| Alcohol use disorder, phase 3 (RENEW-ALC-1/2) | Subcutaneous (once weekly, consistent with phase 1) | Specific phase 3 dose(s) not independently confirmed | Once weekly (inferred) | 56 weeks |
| Major depressive disorder, phase 3 (RENEW-MDD-1) | Subcutaneous (once weekly, consistent with phase 1) | Specific phase 3 dose(s) not independently confirmed | Once weekly (inferred) | Not specified in sources reviewed |
| Community, forum, or vendor protocol | Not applicable | Not applicable, brenipatide has never been sold in any form | Not applicable | Not applicable |
No established or reliably sourced consumer dosing information was identified. Brenipatide has never been sold, legitimately or gray-market, and no forum or vendor protocol exists for it as of this review. Every dosage figure documented on this page comes from Eli Lilly's own registered phase 1 clinical trial.
Any product marketed under the name "brenipatide" or "LY3537031" outside a Lilly-run clinical trial should be treated as counterfeit, since no legitimate or gray-market supply chain exists.
Recorded as an observation about what is published elsewhere. No figure here is a dose, a protocol, or a recommendation, and nothing in this section is evidence that any amount is safe or effective.
Side effects, risks, and limitations
In the phase 1 study, treatment-emergent adverse events occurred in 57.6% of brenipatide recipients versus 42.9% on placebo. Gastrointestinal adverse events were equal between groups at 25%, notably different from marketed GLP-1 drugs where GI side effects are dose-limiting and clearly elevated over placebo. The adverse event that was clearly elevated over placebo was dysesthesia, abnormal or altered skin sensation, in 15.2% of brenipatide recipients versus 0% on placebo. No serious adverse events or deaths occurred in either arm, and discontinuation for adverse events was low, about 2% (4 participants).
This is a single completed phase 1 study in participants with overweight or obesity, not the alcohol use disorder or depression populations the drug is now being tested in. It does not establish long-term safety, safety in psychiatric populations who may be on other medications, or efficacy for any indication. Because brenipatide has never been available for purchase, the purity, mislabeling, and contamination concerns that apply to other entries on this site do not apply here; the only real risk is counterfeit material sold under its name.
Regulatory and developmental status
Brenipatide is not approved anywhere for any indication. It is an investigational compound available only to enrolled participants in Lilly-sponsored clinical trials. It is currently in phase 3 for alcohol use disorder (two trials) and major depressive disorder (one trial), with phase 2 programs registered in opioid use disorder, tobacco use disorder, bipolar disorder, schizophrenia, asthma, irritable bowel syndrome, and COPD, 13 phase 2/3 studies total as of this review. Topline data for the alcohol use disorder program is expected around 2028; the depression trial runs on a comparable timeline. Approval for any indication, if it happens, is realistically 2029 or later. Date verified: 2026-09-25.
Two other investigational-pipeline compounds profiled on this site sit at a similar pre-approval stage: Amycretin, Novo Nordisk’s dual GLP-1/amylin agonist for obesity, and Klotho, an investigational longevity-related protein. Neither is approved or sold anywhere either.
Frequently asked questions
What is brenipatide (LY3537031)?
An investigational dual GIP/GLP-1 receptor agonist from Eli Lilly, the same receptor pairing as tirzepatide, but designed for brain-related targets rather than weight loss. It is not approved anywhere.
How does brenipatide work?
It activates GIP and GLP-1 receptors, reportedly concentrated on reward and neuroinflammation circuitry in the brain rather than gut-driven satiety pathways, at doses far lower than weight-loss GLP-1 drugs use.
What dosage has been studied?
Weekly subcutaneous doses of 0.3 to 4.5 mg in a completed phase 1 trial with 212 participants. Phase 3 dosing has not been independently confirmed as of this review.
What dosage commonly circulates online?
None. Brenipatide has never been sold, legitimately or otherwise, so there is no online-circulating dose to report.
Has brenipatide been studied in humans?
Yes, in one completed phase 1 safety and dose-finding trial. It is now in phase 3 trials for alcohol use disorder and depression, but no efficacy results have been published yet.
Is brenipatide approved?
No, and it is not close. Even on an aggressive timeline, approval for any indication would land no earlier than 2029.
What remains unknown?
Whether brenipatide actually reduces drinking or depressive symptoms in its phase 3 trials, which read out around 2028, what dose those trials are using, its long-term safety profile, and whether the dysesthesia signal seen in phase 1 persists or worsens with longer exposure.
Bottom line
Brenipatide is Eli Lilly’s attempt to build a GLP-1-class drug specifically for the brain rather than the gut, aimed at alcohol use disorder and depression instead of weight loss. The strongest evidence right now is a single, well-designed phase 1 safety study: low, well-tolerated doses, GI side effects no worse than placebo, and a new side effect, dysesthesia, worth watching. No dosage information circulates online because brenipatide has never been sold in any form, and any product using this name outside a Lilly trial should be treated as counterfeit. Efficacy for its target indications is unproven and won’t have a real readout until around 2028. The genuine human evidence that GLP-1 receptor activity affects drinking behavior comes from published trials of semaglutide, a related but different compound, not from brenipatide itself.