Nuzefatide Pevedotin (BT5528)_Dosage, benefits & legal status
Also known as BT5528
A pancreatic cancer pivot with no published pancreatic response.
Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.
What is Nuzefatide Pevedotin (BT5528)?
Plain language first. The technical label stays, but it never stands alone.Overview
This is a cancer drug built on an unusual idea. Instead of attaching a chemotherapy payload to a large antibody that circulates for days, it attaches one to a tiny constrained peptide that finds its target, delivers the payload and clears within about an hour. The site already covers its near-twin, zelenectide pevedotin: same architecture, same linker, same payload, different targeting loop and a different cancer. The story worth knowing is what the company did in 2026. It cut back the bladder cancer twin and pushed this one into pancreatic cancer, a disease where its own earlier program treated eight patients and never published a single response. The pancreatic bet rests on biology and on data nobody outside has seen.
Nuzefatide pevedotin is a bicyclic peptide drug conjugate targeting EphA2, carrying monomethyl auristatin E through a cleavable valine-citrulline linker. The targeting element is an 18-residue peptide whose three cysteines are tris-thioether bonded to a central 1,3,5-triazinane scaffold, forming two constrained six-residue loops. Because the loops are closed through a chemical scaffold rather than disulfide bonds, they cannot be reduced open in circulation. The full named chain runs to 29 units because a beta-alanine followed by a ten-unit sarcosine spacer carries the linker and payload. Molecular weight is 4402.18 and the FDA substance registry classes the entity as a chemical rather than a protein. The design rationale is pharmacokinetic: roughly 40 times smaller than an antibody drug conjugate with one payload instead of about four, giving a conjugate half-life under an hour against days for antibody conjugates, with the aim of penetrating tumor tissue quickly and clearing before causing systemic damage.
What it's used for
Investigational only, in metastatic pancreatic ductal adenocarcinoma after prior treatment. It is given by vein in a trial and is not approved or sold anywhere.
How does Nuzefatide Pevedotin (BT5528) work?
What it does in the body, and where.Two things make this compound worth understanding: how a peptide is made rigid enough to work like an antibody, and why making it small changes the whole pharmacokinetic bargain.
- 01The loops are welded, not tiedAn 18-residue peptide carries three cysteines, and all three are thioether bonded to one central 1,3,5-triazinane scaffold. A three-armed chemical hub holding three points of one chain creates two closed loops of six residues each. Because those loops are closed through carbon-sulfur bonds to a scaffold rather than through disulfide bridges, nothing in the bloodstream can reduce them open. A short peptide that would normally flop into any shape becomes a rigid binding surface.
- 02The target is EphA2EphA2 is a receptor found at elevated levels on many solid tumors and at low levels on healthy adult tissue, the usual requirement for a delivery target. The targeting loop binds it, and the difference between this compound and its sibling is essentially that loop: zelenectide pevedotin binds nectin-4 instead. Same scaffold, same linker, same payload, different address.
- 03A long tail carries the warheadThe full named chain is 29 units rather than 18 because a beta-alanine followed by ten sarcosine units forms a spacer. That spacer carries the valine-citrulline linker with its p-aminobenzyl carbamate element and the monomethyl auristatin E payload, holding the cytotoxic cargo away from the binding face so it does not interfere with target recognition. The linker is cleaved by enzymes inside the tumor, releasing free payload there.
- 04Small and fast is the whole betThe conjugate is roughly 40 times smaller than an antibody drug conjugate and carries one payload rather than about four. Its measured half-life is well under an hour, against 3.4 to 12 days for antibody conjugates using the same payload. The intended consequence is that it diffuses into tumor tissue that an antibody struggles to penetrate, drops its payload and then leaves the circulation before doing systemic harm. Reported tumor to plasma payload ratios of 9.3 to 10.1 at 24 hours are the evidence offered for that. Whether the bargain pays off in pancreatic cancer is exactly what the current trial has not yet answered.
A schematic of the compound's mechanism, not a diagnostic image.
What else is it used for?
Each group carries its own evidence level.Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.
The pancreatic pivot has no published pancreatic response
peer-reviewed-human- No dataAcross 128 monotherapy phase I and II patients, eight had pancreatic cancer. No pancreatic response appears in either the journal report or the conference poster.
- Human trialThe current phase 2 trial enrolls 39 patients, single-arm and open-label, with objective response rate as its primary outcome.
- No dataThe phase 2 dose of 8 mg/m2 is above the 6.5 mg/m2 recommended from phase I, and that figure comes from a company release rather than the registry.
What was actually shown in phase I
peer-reviewed-human- Human trialUrothelial cancer objective response rate 34%, 10 of 29 patients.
- Human trialThe program's only complete response was in ovarian cancer and lasted beyond 16 months.
- No dataAn unresolved bleeding discrepancy: 5 of 45 patients, 11.1%, with one grade 3 gastric hemorrhage in the journal report, against no hemorrhage at any grade across 128 patients on the poster.
The architecture is the interesting part
peer-reviewed-human- lab-analysisAn 18-residue peptide with three cysteines tris-thioether bonded to a central 1,3,5-triazinane scaffold, forming two six-residue loops that cannot be reduced open.
- lab-analysisThe full named chain is 29 units because a beta-alanine plus ten-sarcosine spacer carries the valine-citrulline linker and the payload. Molecular weight 4402.18.
- Human trialRoughly 40 times smaller than an antibody drug conjugate with one payload instead of about four, conjugate half-life 0.38 to 0.71 hours against 3.4 to 12 days, tumor to plasma payload ratio 9.3 to 10.1 at 24 hours.
The company switched horses in 2026
none- RegulatoryOn April 30, 2026 the company disclosed deprioritization of zelenectide pevedotin, a workforce cut of roughly 30%, runway into 2030, and two trials of that program put forward for discontinuation.
- RegulatoryFive months earlier and later respectively, this compound entered a pancreatic phase 2 and received orphan drug designation in September 2026, stated in an SEC-filed release of October 29, 2026.
- No dataNothing is offered for sale under this name or its code anywhere in the channels checked.
The first error is implying a pancreatic track record. Eight pancreatic patients were treated across a 128-patient program and no pancreatic response has ever been published, so the new trial is a bet on EphA2 biology and on unpublished 2026 data rather than a follow-up to a signal. The second is the bleeding question: a conference poster covering 128 patients reports no hemorrhage at any grade, while the journal report describes bleeding in 5 of 45 patients including one grade 3 gastric hemorrhage, so no claim that bleeding did not occur should rest on the poster alone. The third is the dose. The 8 mg/m2 every two weeks now being given is above the 6.5 mg/m2 recommended from phase I, and it appears in a company quarterly release rather than the trial registry. The fourth is confusing it with zelenectide pevedotin: identical scaffold, linker and payload, different targeting loop, different target and different cancer, and the company deprioritized that one in the same year it promoted this one. Last, the orphan drug designation rests on the sponsor's own filed statement, since FDA's orphan drug database could not be used to confirm it.
The published record
Papers and trials about Nuzefatide Pevedotin (BT5528)
Searched: nuzefatide, nuzefatide pevedotin, BT5528.
Left out: pevedotin (the shared INN stem for the linker and payload. It matches zelenectide pevedotin, which has its own slug on this site, so the stem itself is the contamination vector and must never be used alone); BT8009 (the sibling compound, same scaffold, same linker, same MMAE payload, different targeting loop, targeting nectin-4 in bladder cancer. It has its own slug); zelenectide pevedotin (the sibling by name, for the same reason); bicyclic peptide (the platform term covering the whole portfolio including BT7480 and others, plus an unrelated chemistry literature on constrained peptides); MMAE (monomethyl auristatin E, the payload shared with a long list of antibody drug conjugates); monomethyl auristatin E (the same payload spelled out); EphA2 (the target, with a substantial cancer biology literature that is almost entirely not about this conjugate); Duravelo (the trial program name belonging to the sibling compound); BicycleTx (a company name spanning the portfolio).
8 papers tagged human · 4 not reviews or lab · 1 clinical trial publications
2 registered trials · none with posted results
Furthest stage reached: Phase 2, under way
Counted from Europe PMC indexing, not read by a person; a human tag can land on reviews, commentary or lab papers; clinical trial publications is the narrower count.
At a glance
Four things to know about Nuzefatide Pevedotin (BT5528)
Evidence
Investigational
Category
Longevity and energy
Common vial
Varies
Half-life
Under an hour for the conjugate
How much, and do you cycle it?
The range, and whether you take breaks.8 mg/m2 every 2 weeks in the phase 2 trial, every 2 weeks. Every 2 weeks, continuously while the disease responds Trial dose
Oncology dosing continues on a fixed schedule until progression or unacceptable toxicity rather than in cycles on and off. The trial measures response over roughly three years.
How long does it stay in the body?
The half-life, and where the figure comes from.Under an hour for the conjugateHuman study
The intact conjugate clears in well under an hour, against 3.4 to 12 days for antibody drug conjugates carrying the same payload. That contrast is the point of the platform rather than a drawback: the molecule is intended to reach tumor tissue quickly and leave the circulation before causing systemic damage, with reported tumor to plasma payload ratios of 9.3 to 10.1 at 24 hours offered as evidence that the payload stays where it was delivered.
Source: First-in-human phase I dose escalation, Journal of Clinical Oncology 2024, volume 42, pages 3443 to 3452, DOI 10.1200/JCO.23.01107
You can compare this against the whole library to see where it sits.
How is it given?
Dosing context and source notes.Dosed by body surface area and given by intravenous infusion, so no vial draw can be shown and the calculator does not apply. The 8 mg/m2 figure comes from a company quarterly release rather than the trial registry, and it sits above the 6.5 mg/m2 recommended phase 2 dose from the earlier study.
How do you store it?
Before mixing, and after.Given in a hospital or trial clinic, so the pharmacy stores it.
Nuzefatide Pevedotin (BT5528) goes into a vein and is prepared by hospital, clinic or trial pharmacy staff, following the product label or the trial protocol. Some products like this are ready-made solutions and others are powders mixed just before use, often with hours rather than weeks of shelf life once prepared. It is not a medicine people store at home.
What are the side effects and cautions?
Known cautions and warnings for this compound.Who should avoid it
- Any expectation of pancreatic benefit from published data: eight pancreatic patients were treated across the 128-patient program and no response in that group has been reported
- Reading the conference poster as evidence that bleeding does not occur, given the journal report of 5 bleeding events in 45 patients
- Treating it as interchangeable with zelenectide pevedotin, a conjugate aimed at a different protein in a different cancer
Stop and get help
- New numbness, tingling or weakness in the hands or feet, a possible sign of payload-related nerve damage
- Any bleeding, black stools or vomiting blood, given the unresolved bleeding signal
- Fever or signs of infection while blood counts may be low
Common effects
- Nothing established for this compound specifically beyond the effects expected from its cytotoxic payload.
Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.
Is Nuzefatide Pevedotin (BT5528) approved?
And where the numbers on this page come from.No. Nuzefatide Pevedotin (BT5528) is not approved anywhere and is currently in company-run clinical trials. There is no legal route to obtain it outside a trial.
- Approval statusInvestigational
- RouteInto a vein (intravenous infusion)
- Checked1 November 2026
- DoseFrom published clinical trials. Not approved by a regulator for this dose.
- Vial sizeFrom what vendors typically list; not a recommendation.
- Sources
What has happened recently
The compound holds FDA orphan drug designation granted in September 2026. That designation is stated in a company release filed with the Securities and Exchange Commission on October 29, 2026; FDA's own orphan drug database could not be used to confirm it independently, so it rests on the sponsor's filed statement. The current trial is NCT07450859, a phase 2 study of BT5528 in metastatic pancreatic ductal adenocarcinoma, sponsored by BicycleTx Limited, recruiting, 39 participants estimated, single-arm and open-label, enrolling after one prior line of therapy or after a second-line KRAS inhibitor, dosed intravenously every two weeks, with objective response rate by RECIST assessed by the investigator as the primary outcome over roughly three years. Both the start date and the first posting are March 5, 2026. The registry does not state a dose level; the 8 mg/m2 figure comes from a company quarterly release. The context for this trial is the sibling compound. On April 30, 2026, in a quarterly release filed as an SEC exhibit, the company disclosed that it was deprioritizing zelenectide pevedotin, cutting roughly 30% of its workforce, extending runway into 2030 and seeking to discontinue two of that program's trials. Nothing is on sale: searches of the usual channels return nothing at all offered under this name or its code.
You can compare this against the whole library, or read how to check a seller.
What else is like Nuzefatide Pevedotin (BT5528)?
Others in Longevity and energy, side by side.If you're weighing Nuzefatide Pevedotin (BT5528), it's worth reading MOTS-c, Epitalon, and NAD+ in the same class.
A pancreatic cancer pivot with no published pancreatic response.
- Dose
- 8 mg/m2 every 2 weeks in the phase 2 trial
- How often
- Every 2 weeks
A shot people use for energy, metabolism, and healthy aging.
- Dose
- 1 up to 5 mg per day (start low, increase slowly)
- How often
- Daily
A longevity peptide taken in short courses for sleep and anti-aging.
- Dose
- 5 up to 10 mg per day (start low, increase slowly)
- How often
- 10-20 day courses
A cellular fuel taken for energy, focus, and anti-aging.
- Dose
- 50 up to 100 mg per dose (start low, increase slowly)
- How often
- 2-3x/week
Guides for this compound
- How to Reconstitute a Peptide
Mix peptide powder with bacteriostatic water, step by step.
- How to Read an Insulin Syringe
Read the units, convert to millilitres, and draw the exact dose.
- mcg vs mg: The Peptide Dosing Mistake to Avoid
Your vial says mg and your protocol says mcg. Here is the conversion and how to check it.
- How to Read a Peptide COA
What the purity number does and does not tell you, and how to spot an edited report.
- How to Vet a Peptide Vendor
Independent COAs, HPLC purity, and the red flags that mean walk away.
Sources
- ClinicalTrials.gov record NCT07450859(2026)A phase 2 study of BT5528 in patients with metastatic pancreatic ductal adenocarcinoma, sponsor BicycleTx Limited, recruiting, 39 participants estimated, single-arm and open-label. Eligibility is after one prior line of therapy or after a second-line KRAS inhibitor. Dosing is intravenous every two weeks and the registry states no dose level. Primary outcome is objective response rate by RECIST, investigator assessed, over about three years. Start date and first posted date are both March 5, 2026.
- Journal of Clinical Oncology, first-in-human phase I dose escalation of a bicyclic peptide conjugate(2024)Volume 42, pages 3443 to 3452. The main published clinical report. Responses were seen in urothelial cancer, with an objective response rate of 34%, 10 of 29, and the program's only complete response was in ovarian cancer and lasted beyond 16 months. The paper describes the pharmacokinetic contrast with antibody drug conjugates: roughly 40 times smaller, one payload against about four, conjugate half-life 0.38 to 0.71 hours against 3.4 to 12 days, and tumor to plasma payload ratios of 9.3 to 10.1 at 24 hours. It reports bleeding events in 5 of 45 patients, 11.1%, including one grade 3 gastric hemorrhage, a figure a later conference poster covering 128 patients does not reflect.
- FDA substance registration record for nuzefatide pevedotin(2026)UNII CIT3DOS0DW, molecular weight 4402.18. The record describes an 18-residue peptide with three cysteines tris-thioether bonded to a central 1,3,5-triazinane scaffold forming two six-residue loops, with the full named chain running to 29 units because of a beta-alanine plus ten-sarcosine spacer carrying the valine-citrulline linker and payload. The registry classes the entity as a chemical rather than a protein.
- BicycleTx quarterly release disclosing the sibling program change(2026)The April 30, 2026 quarterly release, filed as an SEC exhibit, disclosed deprioritization of zelenectide pevedotin alongside a workforce reduction of roughly 30%, runway extended into 2030, and two trials of that program put forward for discontinuation. A later release filed October 29, 2026 states the orphan drug designation for this compound, granted in September 2026. These filings are the source for the strategic context and for the designation, since FDA's own orphan drug database could not be used to confirm the latter.
Beyond these, 8 records are indexed. Browse the records