Fluciclatide
An RGD peptide scan agent for new blood vessels in tumours and healing heart muscle
Fluciclatide is a small cyclic peptide carrying the arginine-glycine-aspartic acid (RGD) motif, the sequence that integrins on new blood vessels recognise. Labelled with fluorine-18, it shows where αvβ3 and αvβ5 integrins are on a PET scan. GE Healthcare developed it as AH111585; studies in cancer patients tested whether it could show early that an antiangiogenic drug was working, and cardiology groups used it to image repair after heart attack. It was never approved.
Used in human trials: Up to 370 MBq, Single injection per scan, Intravenous (Fluorine-18 fluciclatide PET, solid tumours (reproducibility study)) Details ↓
Recommended Dosing
Used in human trials
No manufacturer dose exists for this use: these are amounts given in published trials, not recommendations.
What is it?
Tumours need new blood vessels to grow, and the endothelial cells lining those vessels switch on integrins such as αvβ3 and αvβ5, adhesion receptors that bind the RGD motif in proteins like vitronectin and fibronectin. Several companies and academic groups built radiolabelled RGD peptides to image this process. Fluciclatide, first called AH111585, was GE Healthcare's fluorine-18 version: a cyclic RGD peptide joined to a polymer chain that carries the label.
The first human studies, in 2008, gave it to eight healthy volunteers and seven women with metastatic breast cancer. It caused no drug-related adverse events, left the blood quickly, was cleared partly through the kidneys and partly through the liver and gut, and gave an effective dose comparable to other fluorine-18 tracers. In the patients it showed all 18 tumours seen on CT, sometimes as a ring around a dead centre, the pattern expected where new vessels grow at the edge. Kinetic modelling studies then worked out how to separate true receptor binding from blood flow, and found that the late signal does not simply mirror perfusion.
Because antiangiogenic drugs often stop vessel growth before a tumour shrinks, fluciclatide was tested as an early readout. In mice, uptake fell within days of sunitinib or paclitaxel treatment, before tumour size changed. A multicentre study in 39 patients showed that uptake on two scans a few days apart, with no treatment between, agreed within about 18-20%, close to FDG. In 14 women with platinum-resistant ovarian cancer starting pazopanib and paclitaxel, higher uptake before treatment predicted longer progression-free survival, and kinetic measures fell after a week of pazopanib.
Outside cancer, Edinburgh cardiologists found that fluciclatide gathered at sites of recent heart attack but not at old scars or in healthy hearts, and that segments with more uptake were more likely to recover function. In the aorta, uptake tracked plaque burden and was higher after recent heart attack. A tissue study found specific binding in abdominal aortic aneurysm walls.
Most fluciclatide trials ended between 2011 and 2016 and several were withdrawn, and no phase 3 study is listed. It has no FDA or EMA approval. Like other fluorine-18 tracers it is made in a cyclotron facility and injected in a PET department; it has no use outside that setting. Other RGD tracers with their own entries are compared below.
Mechanism of Action
Fluciclatide is a scan agent. It shows where integrins are; it is given in microgram amounts and is not a treatment.
Angiogenesis signal
These integrins rise on growing vessels; uptake fell when antiangiogenic drugs cut vessel density in mice (2009 and 2011 studies).
Fluorine-18 PET
Late uptake reflects binding rather than blood flow, so scans are taken about an hour after injection (2014 study).
Tissue repair
Uptake at recent infarcts predicted which heart segments recovered (2017 study).
Published Research
These studies were read from their PubMed abstracts on October 29, 2026: nine in people, two in mice and one on human tissue. Three are titled for integrins or tracers in general and are carded because their abstracts name fluciclatide as the tracer used.
Healthy volunteers: safety and radiation dose
Eight healthy volunteers were scanned for up to 4 hours. There were no serious or drug-related adverse events. About 37% left through the urine; the liver, gut and kidneys took most of the early activity. The bladder wall, kidneys and heart wall received the highest doses, and the effective dose was 26 µGy per MBq.
Phase 1 in metastatic breast cancer
Seven women with 18 CT-detected tumours were scanned. The tracer was safe, stable in plasma and showed every tumour, as a bright spot or, in the liver, as a gap against bright normal tissue. Uptake was often at the rim of tumours, consistent with new vessels around a necrotic core.
How to measure binding in breast cancer
Repeated scans with arterial blood sampling in metastatic breast cancer fitted a two-tissue reversible model best. The k3/k4 ratio, a measure of specific binding, was much higher in lung and liver metastases than in healthy tissue, making it a better index than total distribution volume.
Binding versus blood flow
Patients with lung cancer or melanoma had both fluciclatide and oxygen-15 water PET. Early delivery of the tracer matched perfusion closely, but its retention at 60 minutes did not, supporting late imaging as a measure of binding rather than flow.
Melanoma and kidney tumours vs tissue staining
All 18 operable tumours took up the tracer; kidney cancers more than melanoma metastases, and chromophobe kidney cancers more than other types. Uptake rate correlated best with αvβ5 staining (r 0.83-0.91). It was well tolerated.
Multicentre test-retest reproducibility
Thirty-nine patients with solid tumours had two scans 2-9 days apart (up to 370 MBq each) with no treatment between. Lesion uptake correlated at r 0.92-0.94, with 95% limits of repeatability of 35-39%, about 18-20% variability, similar to well-run multicentre FDG studies.
Ovarian cancer on pazopanib and paclitaxel
In a phase 1b study of 14 women with platinum-resistant ovarian cancer, 54% responded to the drug combination. Higher baseline fluciclatide uptake predicted longer progression-free survival, and tracer delivery and retention fell after one week of pazopanib, consistent with an antiangiogenic effect.
Repair after myocardial infarction
Twenty-one patients scanned two weeks after a heart attack showed uptake at the infarct (ratio 1.34 against 0.85 in remote muscle), but none at old infarcts or in healthy volunteers. Segments with more uptake were more likely to regain function at nine months; uptake did not track infarct size or CRP.
Aortic atherosclerosis
Forty-six people received a median 229 MBq. Uptake in the aortic wall matched integrin, inflammation and vessel-growth staining in surgical samples, correlated with wall thickness and plaque volume, and was higher after recent heart attack than in stable disease (1.29 vs 1.21).
Mice: reading antiangiogenic effects
The tracer cleared quickly from blood and normal organs and reached about 1.5-2.2% of the dose per gram in lung tumours. Paclitaxel lowered vessel density and tracer uptake, and the VEGF-receptor drug ZD4190 cut uptake by 31.8% while untreated tumours rose 26.9%.
Mice: sunitinib response in glioblastoma
In U87 glioblastoma xenografts, two weeks of sunitinib reduced tumour fluciclatide uptake against untreated controls while muscle uptake was unchanged, and vessel density fell. Tumour volume did not change, so the scan showed an effect before size did.
Human aneurysm tissue
Of eight PET tracers tested by autoradiography on abdominal aortic aneurysm walls removed at surgery, only fluciclatide bound specifically, suggesting αvβ3 integrin in aneurysms could be imaged.
Dosing Data
Fluciclatide has no approved label. It is dosed by radioactivity for a single scan; rows are from the carded human studies.
Educational information, not medical advice. Each dose above is tagged with its source: an approved label, a published human study, animal data, or amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.
What a Buyer Needs to Know
What is sold, how it is mixed, stored and taken, and what is known about its safety, quality and legal status. Each part names its source. Where we have none, it says unknown.
What is sold
Unknown: we hold no regulator's label that says in what form Fluciclatide is supplied. It is a radioactive drug: the next part says where it is prepared and given.
Mixing a vial: a worked example
Nothing to mix at home, and no syringe units to work out: Fluciclatide is a radioactive drug, prepared and given in nuclear-medicine departments, and its dose is an amount of radioactivity (MBq or GBq), not a weight.
This page's dosing note: “Investigational radioactive imaging agent, prepared and given only in nuclear-medicine departments within studies; these are study activities, not recommendations.”
Source: this page's own note in Dosing Data below; the amount of each dose row in Dosing Data below.
Storage before and after mixing
Unknown: no label on file says how Fluciclatide is stored. It is a radioactive drug held by the nuclear-medicine department that prepares and gives it (see the part above); the home rules for a mixed vial in the mixing guide do not apply to it.
How it is taken
As it was given in human studies: Intravenous (Single injection per scan; Fluorine-18 fluciclatide PET, solid tumours (reproducibility study)).
Source: Used in human trials: the route and frequency of each row in Dosing Data below.
What to expect, and when
How long it stays in the body: not established by a measurement cited on this entry.
How long the doses were given: Fluorine-18 fluciclatide PET, solid tumours (reproducibility study): Scans at 40, 65 and 90 minutes; Fluorine-18 fluciclatide PET, aortic atherosclerosis: One scan.
When effects appear: unknown; no source on this page gives a time to effect for Fluciclatide. Results reported in the studies are under Published Research.
Source: Used in human trials, the duration of each row in Dosing Data below.
Side effects, and when to stop or get help
From the Side Effects section: No serious or drug-related adverse events in healthy volunteers; well tolerated in cancer patients; Radiation: 26 µGy per MBq effective dose, highest to bladder wall, kidneys and heart wall. Full list and cautions ↓
When to stop or get help: unknown; no label or trial on file sets rules for stopping Fluciclatide. Treat a severe or unexpected reaction as a reason to stop and see a doctor.
Source: the Side Effects section below (“From the human studies above”).
Interactions
Unknown: a PubMed search for human interaction studies of Fluciclatide (reviewed 2026-10-28) found none. Unknown is not the same as safe to combine.
Every peptide's record, with its source: the interaction matrix.
Checking what you bought
Unknown: no published independent test of Fluciclatide products is in our lab-results database yet, so how products sold under this name measure up is not known.
To read a certificate of analysis, paste it into the COA decoder; it checks the measured mass against Fluciclatide's expected mass, 1,816.0 Da, from this entry's molecular data. Trust & Verification explains what independent testing can and cannot show.
Legal status
US: In Clinical Trials (Not approved: Drugs@FDA and the EMA medicines list hold no record (searched October 28, 2026)). Sport: Prohibited (S0 catch-all).
Country by country ↓ · Regulatory tracker
Source: this entry's approval status and the WADA Prohibited List, as in Legal Status below.
Side Effects & Contraindications
Reported Side Effects
From the human studies above.
Contraindications & Cautions
No approved label exists, so there are no official contraindications. Points from the studies:
Legal Status
Fluciclatide was never approved anywhere checked.
Frequently Asked Questions
?What is fluciclatide?
A fluorine-18 labelled cyclic RGD peptide used in PET research to image αvβ3 and αvβ5 integrins, markers of new blood vessels.
?What was it for?
Mainly to see whether antiangiogenic cancer drugs were working before tumours shrank, and in cardiology to image repair after heart attack.
?Is it a treatment?
No. It is a trace-dose imaging agent.
?Is it approved?
No, and no trial is currently recruiting on ClinicalTrials.gov.
References
- [other] PubChem CID 59707743 (synonyms fluciclatide, AH-111585): formula C75H115FN18O27S3, molecular weight 1816.0. Read October 28, 2026. https://pubchem.ncbi.nlm.nih.gov/compound/59707743
- [registry] ClinicalTrials.gov API v2, read October 28, 2026: NCT00918281 (phase 2, reproducibility in solid tumours, completed); NCT00565721 (phase 2, proof of concept, completed); NCT01608009 (phase 1, ovarian cancer, completed).
- [clinical-trial] McParland BJ, et al. "The biodistribution and radiation dosimetry of the Arg-Gly-Asp peptide 18F-AH111585 in healthy volunteers." J Nucl Med, 2008;49(10):1664-7. PMID: 18794263.
- [clinical-trial] Kenny LM, et al. "Phase I trial of the positron-emitting Arg-Gly-Asp (RGD) peptide radioligand 18F-AH111585 in breast cancer patients." J Nucl Med, 2008;49(6):879-86. PMID: 18483090.
- [pubmed] Tomasi G, et al. "Quantification of receptor-ligand binding with [¹⁸F]fluciclatide in metastatic breast cancer patients." Eur J Nucl Med Mol Imaging, 2011;38(12):2186-97. PMID: 21892622.
- [pubmed] Kenny LM, et al. "Preliminary clinical assessment of the relationship between tumor alphavbeta3 integrin and perfusion in patients studied with [(18)F]fluciclatide kinetics and [ (15)O]H 2O PET." EJNMMI Res, 2014;4(1):30. PMID: 26055935.
- [clinical-trial] Mena E, et al. "[¹⁸F]fluciclatide in the in vivo evaluation of human melanoma and renal tumors expressing αvβ 3 and α vβ 5 integrins." Eur J Nucl Med Mol Imaging, 2014;41(10):1879-88. PMID: 24973039.
- [clinical-trial] Sharma R, et al. "Multicenter Reproducibility of 18F-Fluciclatide PET Imaging in Subjects with Solid Tumors." J Nucl Med, 2015;56(12):1855-61. PMID: 26383153.
- [clinical-trial] Sharma R, et al. "[(18)F]Fluciclatide PET as a biomarker of response to combination therapy of pazopanib and paclitaxel in platinum-resistant/refractory ovarian cancer." Eur J Nucl Med Mol Imaging, 2020;47(5):1239-1251. PMID: 31754793.
- [pubmed] Jenkins WS, et al. "Cardiac α(V)β(3) integrin expression following acute myocardial infarction in humans." Heart, 2017;103(8):607-615. PMID: 27927700.
- [pubmed] Jenkins WS, et al. "In vivo alpha-V beta-3 integrin expression in human aortic atherosclerosis." Heart, 2019;105(24):1868-1875. PMID: 31422361.
- [pubmed] Morrison MS, et al. "Use of a novel Arg-Gly-Asp radioligand, 18F-AH111585, to determine changes in tumor vascularity after antitumor therapy." J Nucl Med, 2009;50(1):116-22. PMID: 19091899.
- [pubmed] Battle MR, et al. "Monitoring tumor response to antiangiogenic sunitinib therapy with 18F-fluciclatide, an 18F-labeled αVbeta3-integrin and αV beta5-integrin imaging agent." J Nucl Med, 2011;52(3):424-30. PMID: 21321268.
- [pubmed] Tegler G, et al. "Autoradiography screening of potential positron emission tomography tracers for asymptomatic abdominal aortic aneurysms." Ups J Med Sci, 2014;119(3):229-35. PMID: 24555564.
Sources & Citations
Studies were read from their PubMed records on October 29, 2026. Regulatory status comes from Drugs@FDA and the EMA medicines list (searched October 28, 2026) and trial listings from ClinicalTrials.gov (October 29, 2026). Grey Peptides sells nothing and links to no vendor.
Medical Disclaimer: This content is for educational and informational purposes only. It is not medical advice, and nothing here is an instruction to obtain or use any compound. Talk to a licensed clinician about your own situation.