Pentixafor
A gallium-68 peptide tracer that maps the CXCR4 receptor in myeloma, lymphoma and adrenal disease
Pentixafor is a small ring-shaped peptide that binds CXCR4, a receptor many blood cancers and some adrenal tumours carry in large numbers. Labelled with gallium-68, it lets a PET scan show where those cells are. It is not approved anywhere; a US phase 3 study in primary aldosteronism was cleared in 2026. It is used only in hospital research imaging, not something anyone can buy.
Used in human trials: 90-158 MBq (mean 134 MBq), Single injection, Intravenous (Study: biodistribution and dosimetry, 5 myeloma patients) 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?
A radioligand scan finds disease by tagging a molecule it carries. The patient receives a tiny amount of a molecule that binds one receptor, with a radioactive atom attached, and a positron emission tomography (PET) camera shows where it collects. The scan is only as good as its target. Pentixafor's target is CXCR4, a chemokine receptor that many cancers, especially blood cancers, carry in large numbers. A 2022 German series of 690 patients found the highest uptake in multiple myeloma, adrenal cortex tumours, mantle cell lymphoma and small cell lung cancer.
Pentixafor is a cyclic pentapeptide, five amino acids closed into a ring, with a DOTA chelator that holds gallium-68. It has a sister compound, pentixather, designed to carry therapeutic isotopes, so a positive pentixafor scan can point to patients who might receive CXCR4-directed radiation treatment. In five myeloma patients given 90 to 158 MBq, the effective dose was 2.3 mSv per 150 MBq, lower than for FDG or gallium-68 somatostatin tracers, with the bladder wall and spleen receiving the most.
It is investigational everywhere. FDA has not approved it, the European Medicines Agency's register holds no record, and the company developing it, Pentixapharm, describes it as a development candidate. In June 2026 FDA cleared the company's application to start PANDA, a US phase 3 study of about 325 adults in which it is used to tell one-sided from two-sided primary aldosteronism, and in July 2026 FDA gave that use Fast Track designation, which speeds contact with the agency but is not an approval. The tracer is made in hospital radiopharmacies for scans in studies and has no use outside them; there is nothing to buy.
Primary aldosteronism is where it may matter most. In this common cause of high blood pressure, one or both adrenal glands make too much aldosterone, and only a one-sided source can be cured by removing the gland. The standard way to tell them apart, adrenal vein sampling, is invasive and technically hard. In a Chinese study of 100 patients, a pentixafor uptake ratio between the two glands agreed with vein sampling in 90% of patients against 54% for CT, and in a prospective cohort of 197 patients, surgery guided by pentixafor gave outcomes similar to surgery guided by sampling. A 2026 meta-analysis was more cautious, putting agreement with sampling at 75% sensitivity and 81% specificity, and called it an adjunct for now.
In blood cancers the results are consistent. A meta-analysis of 11 myeloma studies found it positive in 86% of patients against 61% with FDG, and staging based on it predicted progression better than standard systems in one series. In marginal zone lymphoma it outperformed FDG and changed management in more than half of 41 patients, and a review of lymphoma studies found it most useful in the slow-growing types that FDG often misses. It has also been studied for finding the small pituitary tumours that secrete ACTH of Cushing disease, where it located 93% of tumours against 78% for MRI.
Its limits follow from the receptor. Normal organs such as the spleen and kidneys also take it up, and about a third of the scans in the large German series showed no clear uptake in disease sites. The evidence comes mostly from single centres in Germany, Austria and China, and none of it has yet passed a regulator's review.
Mechanism of Action
Pentixafor carries gallium-68 to the chemokine receptor CXCR4, so cells that carry it show on a PET scan.
CXCR4 binding
The cyclic pentapeptide binds human CXCR4, a receptor many blood cancers and adrenal tumours overexpress.
Positron imaging
The DOTA chelator holds gallium-68, whose positrons the PET scanner detects.
Distribution and clearance
Normal uptake in spleen and kidneys; the bladder wall receives the highest organ dose, showing urinary clearance (dosimetry study).
Published Research
The studies behind pentixafor, read from their PubMed abstracts. All used gallium-68 pentixafor in people; the fluorine-18 NOTA variant is a different molecule and is not included.
Biodistribution and dosimetry
Five myeloma patients received 90 to 158 MBq; the effective dose was 2.3 mSv per 150 MBq, and the bladder wall (12.2 mGy), spleen (8.1 mGy) and kidneys (5.3 mGy) received the highest organ doses.
690 patients with solid and blood cancers
Of 777 scans, 69% showed uptake in disease sites; uptake was highest in multiple myeloma, adrenocortical carcinoma, mantle cell lymphoma, adrenocortical adenoma and small cell lung cancer, and was not related to the specific activity given.
Subtyping primary aldosteronism against vein sampling
In 100 patients, a lateralisation index based on 10-minute uptake identified one-sided disease with an area under the curve of 0.90; at a cut-off of 1.65, specificity was 100% and sensitivity 77%, and agreement with vein sampling was 90% against 54% for CT.
Surgery guided by PET or by vein sampling
In a prospective cohort of 197 patients followed for a median of 27 months, complete biochemical success was 82.1% when surgery followed pentixafor PET and 75.4% when it followed vein sampling, a difference that was not significant.
A retrospective surgical comparison
Of 89 patients who had one adrenal gland removed, complete biochemical success was 91.3% when the decision rested on pentixafor PET and 80.3% when it rested on vein sampling, not a significant difference; PET was most definitive for nodules of 1 cm or more.
Meta-analysis against vein sampling
Pooling 11 studies, sensitivity and specificity for one-sided aldosterone-producing disease, with vein sampling as reference, were 75% and 81%; the authors suggest it as an adjunct where sampling is unavailable or fails.
Meta-analysis in multiple myeloma
Across 11 head-to-head studies and 347 patients, pentixafor PET was positive in 86.3% against 60.9% for FDG PET, with generally higher lesion uptake.
Newly diagnosed myeloma against FDG
In 30 patients scanned with both within a week, pentixafor was positive in 93.3% against 53.3% for FDG, and its bone marrow uptake tracked disease stage and tumour-burden markers.
Myeloma staging and prognosis
In 55 newly diagnosed patients, staging with pentixafor PET/CT separated progression-free survival between all three stages and predicted two-year progression better than FDG staging or the R-ISS (AUC 0.923).
Marginal zone lymphoma against FDG
In 41 untreated patients, pentixafor found more gastric (72% against 40%) and nodal (97.4% against 39.7%) disease than FDG, upstaged 26.8% and led to changed management in 56.1%.
Systematic review in lymphoma
Across 14 studies, lymphomas were pentixafor-avid, including types that FDG often misses; uptake was highest in mantle cell and marginal zone lymphoma, and it looked useful for staging and response.
MALT lymphoma on PET/MRI
In a prospective study of 36 untreated patients, every current lymphoma site showed increased uptake (mean SUVmax 8.6), across orbit, stomach, lung and other sites.
Finding the tumour in Cushing disease
In 43 patients scheduled for pituitary surgery, pentixafor PET/MRI found 92.7% of tumours that secrete ACTH against 78.0% for contrast MRI, and combining both reached 100%; uptake tracked CXCR4 staining and ACTH levels.
Dosing Data
Pentixafor has no approved label. This is the activity given in a published human study, a single injection before PET.
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 Pentixafor 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: Pentixafor 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: “Pentixafor is dosed by radioactivity and prepared in a hospital radiopharmacy shortly before the scan; no reconstitution maths applies.”
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 Pentixafor 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; Study: biodistribution and dosimetry, 5 myeloma patients).
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: Study: biodistribution and dosimetry, 5 myeloma patients: Scans up to 4 hours after injection.
When effects appear: unknown; no source on this page gives a time to effect for Pentixafor. 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: Radiation exposure: an effective dose of 2.3 mSv per 150 MBq, with the bladder wall, spleen and kidneys receiving the most. Full list and cautions ↓
When to stop or get help: unknown; no label or trial on file sets rules for stopping Pentixafor. Treat a severe or unexpected reaction as a reason to stop and see a doctor.
Source: the Side Effects section below (“From the studies above”).
Interactions
Unknown: a PubMed search for human interaction studies of Pentixafor (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 Pentixafor 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 Pentixafor's expected mass, 1,221.4 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 29, 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 studies above. None of the abstracts read reported adverse reactions to the tracer.
Contraindications & Cautions
No approved label exists, so there are no official contraindications. Points from the studies above:
Legal Status
Pentixafor is investigational in every jurisdiction checked.
Frequently Asked Questions
?What is a CXCR4 PET scan?
A scan after an injection of pentixafor carrying radioactive gallium-68. It binds the CXCR4 receptor, which many blood cancers and some adrenal tumours carry, and the PET scanner shows where it has collected.
?Is pentixafor approved?
No. It is investigational everywhere. In 2026 FDA cleared a US phase 3 study in primary aldosteronism and gave that use Fast Track designation, which is not an approval.
?Can I buy it?
No. It is a radioactive tracer made in hospital radiopharmacies for scans within studies, and it has no use outside imaging.
?Could it replace adrenal vein sampling?
Possibly, in some patients. Single-centre studies found high agreement and similar surgical results, but a 2026 meta-analysis found moderate accuracy and called it an adjunct until larger trials report.
?How does it relate to pentixather?
They are sister molecules aimed at the same receptor. Pentixafor carries an imaging isotope; pentixather is built to carry treatment isotopes such as lutetium-177 or yttrium-90.
References
- [other] PubChem CID 54575322 (synonyms Pentixafor, CPCR4-2, boclatixafortide): formula C60H80N14O14, molecular weight 1221.4; its IUPAC name describes a cyclic pentapeptide ring joined to a DOTA chelator. Read October 28, 2026. https://pubchem.ncbi.nlm.nih.gov/compound/54575322
- [registry] ClinicalTrials.gov API v2, read October 28, 2026: NCT04859959 (phase 2/3, gallium-68 pentixafor PET/CT in adrenal masses) and NCT05188872 (gallium-68 pentixafor PET/CT in primary aldosteronism, recruiting).
- [other] Pentixapharm Holding AG, ad hoc announcement (EQS), July 9, 2026: FDA Fast Track designation for [68Ga]Ga-PentixaFor for diagnostic subtyping of adults with confirmed primary aldosteronism; IND for the phase 3 PANDA study cleared (announced June 9, 2026). Read October 29, 2026.
- [other] Pentixapharm Holding AG, second quarter and first half 2026 results (EQS), August 6, 2026: PANDA, a registrational US phase 3 study of about 325 adults, first patient expected in the second half of 2026. Read October 29, 2026.
- [other] European Medicines Agency, medicines list (downloaded October 3, 2026; searched October 29, 2026): no record for pentixafor. No Drugs@FDA record (openFDA, searched October 29, 2026).
- [pubmed] Herrmann K, et al. "Biodistribution and radiation dosimetry for the chemokine receptor CXCR4-targeting probe 68Ga-pentixafor." J Nucl Med, 2015;56(3):410-6. PMID: 25698782.
- [pubmed] Buck AK, et al. "Imaging of C-X-C Motif Chemokine Receptor 4 Expression in 690 Patients with Solid or Hematologic Neoplasms Using (68)Ga-Pentixafor PET." J Nucl Med, 2022;63(11):1687-1692. PMID: 35241482.
- [pubmed] Hu J, et al. "Accuracy of Gallium-68 Pentixafor Positron Emission Tomography-Computed Tomography for Subtyping Diagnosis of Primary Aldosteronism." JAMA Netw Open, 2023;6(2):e2255609. PMID: 36795418.
- [pubmed] Zheng G, et al. "68 Ga-pentixafor PET/CT versus adrenal venous sampling in guiding surgical management for primary aldosteronism: a prospective cohort study on postoperative outcomes." Int J Surg, 2026;112(1):844-853. PMID: 40932337.
- [pubmed] Tan L, et al. "CXCR4-directed PET with (68)Ga-pentixafor versus adrenal vein sampling for the diagnosis of unilateral primary aldosteronism." Endocrine, 2025;89(2):603-613. PMID: 40388084.
- [review] Su J, et al. "AVS-referenced diagnostic performance of (68)Ga-Pentixafor PET/CT for detecting unilateral disease in primary aldosteronism: a systematic review and meta-analysis." Front Endocrinol (Lausanne), 2026;17:1777128. PMID: 42687933.
- [review] Albano D, et al. "Head-to-Head Comparison Between [(18)F]FDG and [(68)Ga]Ga-Pentixafor PET/CT in Multiple Myeloma: A Systematic Review and Meta-Analysis." Cancers (Basel), 2026;18(20). PMID: 42938841.
- [clinical-trial] Pan Q, et al. "Chemokine receptor-4 targeted PET/CT with (68)Ga-Pentixafor in assessment of newly diagnosed multiple myeloma: comparison to (18)F-FDG PET/CT." Eur J Nucl Med Mol Imaging, 2020;47(3):537-546. PMID: 31776631.
- [pubmed] Chen Z, et al. "[(68)Ga]Pentixafor PET/CT for staging and prognostic assessment of newly diagnosed multiple myeloma: comparison to [(18)F]FDG PET/CT." Eur J Nucl Med Mol Imaging, 2024;51(7):1926-1936. PMID: 38286937.
- [clinical-trial] Zhang Z, et al. "CXCR4-targeted [(68)Ga]Ga-PentixaFor PET/CT improves staging and alters management in marginal zone lymphoma: a prospectively recruited head-to-head study with [(18)F]FDG." Eur J Nucl Med Mol Imaging, 2026;53(11):6375-6385. PMID: 42234002.
- [review] Albano D, et al. "The Role of [(68)Ga]Ga-Pentixafor PET/CT or PET/MRI in Lymphoma: A Systematic Review." Cancers (Basel), 2022;14(15). PMID: 35954476.
- [pubmed] Haug AR, et al. "Prospective non-invasive evaluation of CXCR4 expression for the diagnosis of MALT lymphoma using [(68)Ga]Ga-Pentixafor-PET/MRI." Theranostics, 2019;9(12):3653-3658. PMID: 31281504.
- [pubmed] Wu Y, et al. "Diagnostic Accuracy and Value of CXCR4-targeted PET/MRI Using (68)Ga-Pentixafor for Tumor Localization in Cushing Disease." Radiology, 2024;313(3):e233469. PMID: 39688484.
Sources & Citations
Studies were read from their PubMed abstracts; regulatory status from Drugs@FDA, the EMA medicines list and Pentixapharm's July 9 and August 6, 2026 announcements, read October 29, 2026. The stub's searches (October 28, 2026) found 369 PubMed records and 33 ClinicalTrials.gov studies for pentixafor, and no Drugs@FDA or EMA record.
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.