Tracers / [18F]FLT
[18F]FLT
Also written as 3'-deoxy-3'-[18F]fluorothymidine; [18F]FLT; [18F]Fluorothymidine; [F-18]FLT; [F-18]Fluorothymidine; F-18 FLT; FLT
- Radionuclide
- F-18 t½ 109.7 min
- Modality
- PET
- Production route
- Cyclotron liquid target
- Stage
- Clinical research
- Syntheses indexed
- 22
What it is
- Compound class
- Nucleoside analogue
- Target / mechanism
- Phosphorylation by thymidine kinase 1 (TK1) and intracellular trapping (thymidine salvage pathway); marker of cell proliferation PMID 9809561 / DOI 10.1038/3337; PMID 18523066 / DOI 10.2967/jnumed.107.046391
- Clinical application
- Proliferation imaging; treatment response PMID 38247994 / DOI 10.3390/hematolrep16010004
- Theranostic pair
- —
Regulatory status
- FDA
- No Drugs@FDA / openFDA drug registry — no approved application found; search: https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=BasicSearch.process&searchTerm=fluorothymidine
- EMA (centralised)
- —
- Other approvals
- —
- Brand names
- —
Clinical use
- Typical injected activity
- —
- Uptake time
- ~40-60 min post-injection (summed dynamic images) PMID 32047966 / DOI 10.1007/s00259-020-04704-2
Reported in the literature. Not a dosing recommendation.
Published syntheses
| Module | Cassette | Purification | Yield % | RCP % | Precursor / supplier | Source |
|---|---|---|---|---|---|---|
| TRACERlab FX N Pro GE HealthCare | fixed tubing | SPE | 16 ± 2% yes | >99% | 3-N-Boc-5′-O-dimethoxytrityl-3′-O-nosyl-thymidine (I) Toronto Research Chemicals | 36500417 2022 Molecules GE TRACERlab FX N Pro synthesis module — [18F]FLT was obtained in radiochemical yield of 16 ± 2% (decay-corrected) |
| In-house / custom built | custom manifold | SPE | 63±5% yes | >99% | 3-N-Boc-5′-O-dimethoxytrityl-3′-O-nosyl-thymidine (DMTr-Boc-nosyl precursor) ABX | 24365651 2014 J Nucl Med electrowetting on dielectric (EWOD) microfluidic radiosynthesizer, previously developed in our group — an overall decay-corrected radiochemical yield of 63±5% (n=5) |
| TRACERlab FX FN GE HealthCare | custom manifold | HPLC | 23% no | — | Boc-Boc-Nosyl FLT precursor Siemens Molecular Imaging and Biomarker Research | 21769163 2011 J Labelled Comp Radiopharm General Electric Medical Systems (GEMS) TracerLab FXFN automated synthesis modules — the yield of [18F]FLT using this method is 23% (non-decay corrected, n = 5) |
| TRACERlab FX FN GE HealthCare | custom manifold | HPLC | 4.2% no | — | 2,3′-anhydro-cyclic precursor ABX | 21769163 2011 J Labelled Comp Radiopharm the Tracerlab synthesis module was used in the original "out-of-the-box" configuration illustrated in Figure 3 — the yield of [18F]FLT using this method is 4.2% (non-decay corrected, n = 25) |
| — Bioscan | vendor cassette | SPE | 16-39% yes | >99% | 3-N-Boc-5'-O-dimethoxytrityl-3'-O-nosyl-thymidine ABX | 25531913 2015 Appl Radiat Isot Bioscan Coincidence GE FDG reaction module (Fairfield, CT) — we could obtain [18F]FLT in 16–39% decay-corrected radiochemical yield |
| TRACERlab FX FN GE HealthCare | — | HPLC | ≤8.1% yes | 90-99% | 2,3'-anhydro-5'-O-benzoyl-2'-deoxythymidine ABX | 25531913 2015 Appl Radiat Isot GE TRA-CERlab FXF-N reaction module (hereafter TRACERlab module) — led to decay-corrected radiochemical yields no greater than 8.1% |
| In-house / custom built in-house | custom manifold | — | 7% yes | 73 | FLT precursor (3-N-Boc-5′-O-dimethoxytrityl-3′-O-nosyl-thymidine) ABX | 23999726 2013 Molecules For automated radiosynthesis we used custom-made radiosynthesis robot controlled by LabView software. — The corresponding yields of FLT were only 7% and 5% |
| — | — | — | — | — | — | 29470664 2018 Anal Bioanal Chem |
| — | — | HPLC | — | — | — | 29520821 2018 J Labelled Comp Radiopharm |
| — | — | — | 70-90% | — | — | 21989864 2012 Nuklearmedizin |
| — | — | SPE | 23.2+/-2.6% yes | >97% | 3-N-t-butoxycarbonyl-1-[5'-O-(4,4'-dimethoxy triphenylmethyl)-2'-deoxy-3'-O-(4-nitrobenzenesulfonyl)-beta-d-threopentofuranosyl]thymine | 20451400 2010 Appl Radiat Isot using PET-MF-2V-IT-I synthesis module — corrected radiochemical yield of 23.2+/-2.6% (n=6, uncorrected yield: 16-22%) |
| — | — | — | 37.9% | — | 3-N-t-butoxycarbonyl-[5'-O-(4,4'-dimethoxytrityl)-2'-deoxy-3'-O-(4-nitrobenzenesulfonyl)-beta-D-threopentofuranosyl]thymine (thymidine derivative II) | 16129604 2006 Appl Radiat Isot we modified 2-vessel [18F]FDG synthesis module (manufactured by CTI) to produce [18F]FLT — gave the best radiochemical yield (37.9%) when the reaction was carried out at 140 degrees C for 5 min |
| — | — | — | — | — | — | 16203269 2005 Bull Cancer |
| — | — | HPLC | 50.5 +/- 5.2% yes | — | — | 15246372 2004 Nucl Med Biol by modifying a commercial FDG synthesizer and its disposable fluid pathway — [18F]FLT was obtained with a yield of 50.5 +/- 5.2% (n = 28, decay corrected) |
| — | — | SPE | 9.95 ± 0.24% yes | >99% | 3-N-Boc-5'-O-dimethoxytrityl-3'-O-nosyl-thymidine (BOC-Nosyl) | 35466460 2022 J Labelled Comp Radiopharm in the general purpose TRACERlab FX modules — the decay corrected radiochemical yield (RCY) was 9.95 ± 0.24% |
| — | — | HPLC | 24±5% yes | over 99% | 3-N-Boc-5'-O-dimethoxytrityl-3'-O-nosyl-thymidine (Boc-FLT) | 28612546 2017 Sichuan Da Xue Xue Bao Yi Xue Ban CFN-MPS-200 automatic synthesis module — resulted in a radio chemical yield of (24±5)% (after attenuation correction, n =20) |
| — | — | — | 54% yes | — | — | 27314451 2016 Nucl Med Biol |
| — | — | — | — | — | — | 24692121 2014 J Labelled Comp Radiopharm |
| — | — | HPLC | 60 | 99 | — | 22172393 2012 Nucl Med Biol automated them on an Explora General Nucleophilic double-synthesis module — radiochemical yields of up to 60% within 70±10 min |
| — | — | HPLC | 60.2±5.2% | — | (5'-O-DMTr-2'-deoxy-3'-O-nosyl-beta-D-threo-pentofuranosyl)-3-N-BOC-thymine | 17384949 2007 Eur J Nucl Med Mol Imaging commercially available radiochemistry modules (TracerLab MX, GE Healthcare) — Automated synthesis with TBAHCO3 and 20 mg of precursor at 120 degrees C for 10 min of [18F]fluorination led to radiochemical yields of 60.2+/-5.2% after HPLC purification with an MX module (n=10) |
| — | — | HPLC | 19.8% | — | 3-N-Boc-1-[5-O-(4,4'-dimethoxytrityl)-3-O-nosyl-2-deoxy-beta-D-lyxofuranosyl]thymine | 11823132 2002 Nucl Med Biol |
| — | — | — | 13% | — | — | 10773543 2000 Nucl Med Biol |
Precursor
- Common precursor
- 3-N-Boc-5'-O-dimethoxytrityl-3'-O-nosyl-thymidine (BOC-Nosyl) PMID 35466460 / DOI 10.1002/jlcr.3974
- Suppliers seen in the literature
- —
- Cited suppliers in indexed syntheses
- ABX, Siemens Molecular Imaging and Biomarker Research, Toronto Research Chemicals
- Typical final purification
- HPLC
Need this precursor?We can point you to suppliers for [18F]FLT, or handle the enquiry for you.
Get in touchQuality control Pharmacopoeial monograph
- Ph. Eur. monograph
- 2460
- USP monograph
- not verified — the USP-NF monograph index is subscription-only and no public confirmation was found
How this set was arrived at. Cross-checked against Ph. Eur. general monograph 0125 (base set), EANM validation guideline (PMC7016057) and cGRPP guidance (PMC7881071). Draft X-marks consistent with the base set; tracer-specific analytical tests follow the specific monograph where one exists.
Tests listed by reference only. Monograph texts are copyrighted and are not reproduced here. How these are derived
Setting up quality control?We can help you scope the equipment needed to release [18F]FLT.
Get in touch