CBL-514 is an injectable drug candidate from Taiwan's Caliway Biopharmaceuticals that reduces fat in the area where it is injected by killing fat cells rather than shrinking them. Three published Phase 2 trials and a pivotal Phase 3 program make it, by trial stage among the registry entries and published candidates cited below, the most clinically advanced injectable fat-reduction candidate aimed at large body areas. None of that makes it a peptide, a weight-loss drug, or something available to buy — and the search results that surround it get all three of those wrong.
The factual core is narrow enough to state plainly. CBL-514 is a small molecule, not a peptide. Its chemical structure has never been publicly released. It is not approved anywhere in the world, for anything. Its Phase 3 lead trial, SUPREME-01, dosed its first participant in September 2026 and enrolls people with a BMI under 30 — which rules out obesity as the indication. And Caliway is developing it alongside incretin drugs, not against them.
Research-context information only. CBL-514 is an investigational drug not approved by the FDA. Protocols, doses, and reactions reported below come from published clinical trials and self-reported community sources. This article reports what has been documented, not what should be done. Possession or use of investigational drugs outside an authorized clinical trial may be illegal in your jurisdiction. Consult a licensed physician for personal medical decisions.
What CBL-514 Actually Is
Every peer-reviewed publication on the compound describes it the same way. The 2026 Phase 2b paper in Aesthetic Surgery Journal opens by calling CBL-514 "a small-molecule injectable lipolysis agent that induces adipocyte apoptosis." The 2025 Phase 2 paper calls it "a small-molecule injectable drug." Caliway's own corporate releases describe it as a "first-in-class small-molecule 505(b)(1) injection" — 505(b)(1) being the full New Drug Application pathway used for new molecular entities.
That matters for one practical reason: CBL-514's chemical structure has not been publicly disclosed. Drug-pipeline databases note the absence, and no structure appears in any of the three published trial papers. A compound with no published structure cannot be independently identified by a third-party analytical laboratory, which has a direct consequence addressed further down this page.
The second thing worth stating clearly is the delivery model. CBL-514 is not a self-administered weekly injection. Published trial protocols describe a clinician-administered in-office procedure: the Phase IIa trial used up to four treatments, each comprising 60 separate injections into the abdominal adipose layer, at a unit dose of 2.0 mg/cm² up to 300 mg per treatment. Later clinic-administered trial protocols used 2 mg/cm² with a ceiling of 600 mg per treatment, repeated every three to four weeks. This is the same clinical category as the submental deoxycholic-acid injections performed in dermatology offices, not the same category as a vial in a home refrigerator.
The Mechanism, and How Strong the Evidence for It Is
The published mechanism claim is specific. The 2022 Phase IIa paper states that CBL-514 "inhibits the cell survival kinase DYRK1b" and "upregulates the apoptosis mediators caspase 3 and Bax/Bcl-2," and reports that in mature 3T3-L1 adipocytes, CBL-514 produced significantly higher caspase-3 activation and Bax/Bcl-2 ratios than control cells or cells treated with deoxycholic acid.
Two caveats sit in that same paper, and both are load-bearing for anyone trying to judge the compound.
The nonclinical mechanism data are unpublished. The authors attribute the DYRK1b and apoptosis-mediator findings to "Caliway Biopharmaceuticals, unpublished confidential reports," and the discussion section refers to "our unpublished, internal, nonclinical studies with these biomarkers." The mechanism is the company's account of its own proprietary data, not an independently replicated finding.
Apoptosis has never been confirmed in a human participant. The Phase IIa authors state that "no biopsies were conducted in this study." Human apoptosis is inferred from imaging-measured fat loss, and the paper's own wording is appropriately hedged — the authors say the reduction "we believe occurs through adipocyte apoptosis and lipolysis."
Selectivity — why injected adipocytes die and the nerves, vessels and skin around them do not — is asserted rather than explained. The supporting evidence offered is animal histology: repeat-dose toxicology studies in canines and rodents found no CBL-514-related microscopic findings or necrosis in tissues around the injection site. The paper contrasts this with deoxycholic acid, which it describes as "relatively nonselective." Across the human trials, the 2026 Phase 2b report states that no necrosis or nerve injury was observed.
Why CBL-514 Is Not Comparable to an Incretin Drug
This is where most coverage goes wrong, and Caliway's own disclosures are the cleanest correction available.
A December 2025 company release laid out the contrast in its own words. It describes current GLP-1 receptor agonist therapies as achieving weight loss "through appetite suppression," adding that "they mainly shrink adipocyte size and do not reduce adipocyte number." CBL-514 is then positioned as "distinct from GLP-1RA therapies that primarily regulate appetite and energy intake," working instead through "selective induction of adipocyte apoptosis."
Three structural differences follow from that, and they are not matters of degree:
- Systemic versus local. Caliway's own account describes incretin therapies as acting on appetite and energy intake, with fat loss following systemically and its distribution determined by physiology. CBL-514's documented effect, in every published trial, is confined to the subcutaneous layer the needle enters. A trial endpoint measured in millilitres of abdominal fat volume is not the same kind of measurement as a percentage of total body weight.
- Fat-cell number versus fat-cell size. The mechanisms act on different variables. Nothing in the published CBL-514 literature addresses appetite, energy intake, gastric emptying, or glycaemic control.
- Indication and eligibility. SUPREME-01, the pivotal Phase 3 trial, enrols adults with a BMI greater than 18.5 and less than 30 kg/m² and a body weight of at least 50 kg. Its co-primary endpoint is the proportion of participants achieving at least a two-grade improvement on both a clinician-reported and a patient-reported five-point abdominal fat rating scale. That is an aesthetic-medicine registration trial, not an obesity trial.
Caliway is also testing the two approaches together. In August 2026 the FDA cleared an Investigational New Drug application for CBL-0201WR, a randomized placebo-controlled Phase 2 trial of roughly 120 US participants with obesity, or overweight with comorbidities, in which CBL-514 is added after eight weeks of tirzepatide monotherapy across six combination administrations. The stated rationale is that appetite returns after incretin therapy stops and that shrunken adipocytes may re-accumulate energy. MRI-measured abdominal subcutaneous fat volume and body weight are the efficacy endpoints, with DEXA body composition — body-fat percentage, visceral fat and muscle mass — read blinded by a third-party contract research organisation. Framing CBL-514 as a rival to the incretins describes a competition its own developer is not running.
What the Published Trials Reported
Three Phase 2 publications carry the efficacy record, and the quality of the evidence rises across them.
Phase IIa (2022, NCT04698642, 43 participants). Open-label, random allocation, three dose levels, no control group. At the 2.0 mg/cm² unit dose the paper reports a 24.96% abdominal fat-volume reduction in the per-protocol population at first follow-up, corresponding to -119.82 mL. The intention-to-treat figures were lower — 23.13% and 21.85% at the two follow-up visits. The authors attribute part of the per-protocol advantage to visit compliance, and note that COVID-19 interrupted recruitment and follow-up. Every participant reported at least one treatment-emergent adverse event; injection-site pruritus occurred in 95.3% of them. Seven withdrew for treatment-related adverse events, mostly injection-site pain, though the paper's withdrawal section reports eight — an internal inconsistency readers should know about. No serious adverse events occurred.
Phase 2 (2025, 76 participants). Single-blind, randomized 2:1, placebo-controlled, up to four treatments every four weeks, ultrasound-measured. The primary endpoint was the proportion of participants losing at least 150 mL of subcutaneous fat volume from baseline. At eight weeks after the final treatment, 69.6% of CBL-514-treated participants met that threshold versus none on placebo (P < .001), and 60.9% of the CBL-514 group also crossed a 200 mL threshold. Of the 28 participants in the CBL-514 arm who lost at least 150 mL, 42.9% reached it after a single treatment. The most common adverse events were injection-site reactions of mild-to-moderate severity.
Phase 2b (2026, NCT05736107). Single-blind, placebo-controlled, 108 adults with Grade 3 to Grade 4 abdominal subcutaneous fat randomized 1:1, up to four treatments at three-week intervals, and the first trial in the programme to use MRI. In the published full analysis set, 76.7% (23 of 30) of CBL-514 participants achieved at least a one-grade improvement on the clinician-reported scale at 12 weeks versus 18.9% (7 of 37) on placebo (P < 0.0001), with near-identical patient-reported figures. MRI showed a least-squares mean abdominal fat-volume reduction of 152.9 mL ± 17.75 from baseline, a least-squares mean change of -20.3%, both significantly greater than placebo. Most responders improved after one to two treatments. The reported analysis denominators (30 and 37) are considerably smaller than the 108 randomized, which is worth noting when reading the response rates. Tolerability was described as mainly mild, transient injection-site reactions, with no clinically meaningful short-term change in systemic lipid profiles.
For independent context: a 2026 systematic review in Plastic and Reconstructive Surgery covering 25 studies and 3,178 patients treated with injectable lipolytic agents for non-submental fat found significant reductions in localized adiposity reported in 93.75% of studies but statistical significance in only 37.5%, and classed CBL-514 among the "emerging formulations" rather than the established ones. The same review states that deoxycholic acid remains the only FDA-approved injectable lipolytic agent, and only for submental fat.
Beyond the cosmetic indication, a randomized Phase 2a study of CBL-514 for Dercum disease lipomas — a rare painful-fat-tissue condition — was published in JAAD International in 2026, and Caliway is developing a separate designation, CBL-514D, for that disease.
Where the Programme Stands Right Now
As of November 2026 the registry picture is as follows.
| Trial | Phase | Status | Planned enrolment |
|---|---|---|---|
| SUPREME-01 (NCT07140939) | 3 | Recruiting, first dose Sept 2026 | ~320, 13 sites in US + Canada |
| SUPREME-02 (NCT07526974) | 3 | Not yet recruiting | ~320 |
| Long-term follow-up (NCT07733947) | 3 | Not yet recruiting | ~300 |
| CBL-0201WR with tirzepatide | 2 | IND cleared Aug 2026 | ~120 |
| Abdominal fat (NCT07608770) | 2 | Recruiting | ~250 |
SUPREME-01 is randomized, double-blinded and placebo-controlled, with up to four abdominal treatments every four weeks against saline placebo, a primary completion estimate of July 2027, and sites across eleven US states plus British Columbia and Ontario. The long-term trial, CBL-0303, is designed to follow participants who complete SUPREME-01 or SUPREME-02 for up to twelve months after treatment stops, with a double-blind durability stage and an open-label extension; Caliway states it is intended to support future New Drug Application submissions. Caliway reports ten completed trials with finalized statistical reports and more than 544 participants across the programme to date.
Those are company figures for the completed-trial count, and the efficacy and safety record outside the three published papers rests on company disclosures that have not been peer-reviewed. The published record is what the Phase 2 papers contain; everything beyond it is a press release until SUPREME-01 reads out.
Can CBL-514 Be Obtained Today?
No, and the reason is sharper than the usual "it is still in trials."
A registered SUPREME-01 or SUPREME-02 site is the only documented route of access, and SUPREME-01's eligibility window — BMI above 18.5 and below 30 — excludes much of the audience searching for the compound. There is no expanded-access or named-patient pathway in any Caliway disclosure, and no 503A or 503B compounding route exists for an unapproved new molecular entity with an undisclosed structure.
That last point is the one that deserves emphasis. Because CBL-514's chemical structure has never been published, no third-party laboratory can verify that a vial labelled "CBL-514" contains it. Certificates of analysis work by comparing a sample against a known reference standard. With no public structure there is no reference standard, so a COA cannot confirm identity — only that something of a given purity is present. Listings advertising "CBL-514 peptide" compound the problem by misdescribing the compound class: the published literature is unanimous that it is a small molecule. Anything sold under that label is unverifiable by construction, independent of how carefully the seller tests.
Research-chemical vendors do list other investigational and research-labeled compounds that surface in the same searches, and they are separate categories with their own published literature and their own regulatory status. Retatrutide, cagrilintide and AOD-9604 are investigational compounds not approved by the FDA. Tirzepatide, semaglutide and tesamorelin are active ingredients in FDA-approved finished products, and research-chemical and compounded forms of them are not approved either. None of these is a substitute for CBL-514, and none shares its mechanism: the incretin and amylin-pathway compounds act systemically on appetite and energy intake, while tesamorelin and AOD-9604 act through growth-hormone and lipolytic pathways rather than through adipocyte apoptosis.
Vendor listings for those other research compounds are linked below as a market reference. They are separate compounds with their own regulatory status, they are sold as research chemicals, and they are not approved for human use.
