Gallium Ga-68 Dotatate

A positron-emitting somatostatin analog in which the octapeptide DOTA-Tyr3-octreotate carries gallium-68 to somatostatin receptor-positive cells, FDA approved since 2016 as the PET imaging agent NETSPOT for localizing neuroendocrine tumors.

Also referenced as: NETSPOT, 68Ga-DOTATATE, Ga-68 DOTATATE, 68Ga-DOTA-TATE, 68Ga-oxodotreotide, Gallium oxodotreotide

Also appears in: Hormone

COA Public product evidence No certificate records are bound to a tracked Gallium Ga-68 Dotatate product page A record counts here only when a vendor publishes a certificate against one of its own tracked Gallium Ga-68 Dotatate product pages. Other certificates naming this compound may still exist — search the wider certificate database. →

---

What is Gallium Ga-68 Dotatate?

Gallium Ga-68 dotatate is a radiolabeled somatostatin analog: the cyclic octapeptide octreotate (octreotide with a C-terminal threonine in place of threoninol and a tyrosine at position 3) linked through the chelator DOTA to the short-lived positron emitter gallium-68. The peptide portion is the same vector used in lutetium Lu-177 dotatate, which makes the two drugs a theranostic pair: the gallium version shows where somatostatin receptor-positive tissue is, and the lutetium version treats it. Marketed as NETSPOT by Advanced Accelerator Applications, a Novartis company, it was approved by the FDA on June 1, 2016 for use with positron emission tomography (PET) to localize somatostatin receptor-positive neuroendocrine tumors (NETs) in adults and children. The international nonproprietary name for the peptide-chelator conjugate is oxodotreotide.

It is a diagnostic, not a treatment, and it is supplied as a cold kit that a nuclear pharmacy or hospital radiopharmacy labels with gallium-68 shortly before use. It is not a research-market product; it exists as a finished drug for only about an hour after preparation, and the unlabeled DOTA-octreotate precursor is a specialty radiochemistry reagent.

How it works

The molecule has the same two-part design as its therapeutic partner. The peptide is the address label; the radionuclide is the signal.

• Receptor binding. Well-differentiated neuroendocrine tumors overexpress somatostatin receptors, especially subtype 2 (SSTR2). DOTA-Tyr3-octreotate binds SSTR2 with low-nanomolar affinity, higher than the corresponding DOTA-octreotide conjugate in side-by-side receptor assays, and the gallium-chelated form binds at least as tightly (Reubi et al., European Journal of Nuclear Medicine, 2000, 27(3):273-282). After binding, the receptor-ligand complex is internalized, so the tracer accumulates in cells expressing the receptor, and the intensity of uptake reflects receptor density rather than tumor size or activity (FDA label, Clinical Pharmacology section).
• Positron emission. Gallium-68 decays with a half-life of 68 minutes, emitting a positron in about 89% of decays, and decays to stable zinc-68. Each positron annihilates with an electron to produce a pair of 511 keV photons traveling in opposite directions, which is what a PET scanner detects. The short half-life means the radiation dose is delivered quickly and the agent is gone from the body within hours (FDA label, Description section).
• Shared vector for patient selection. Because gallium Ga-68 dotatate and lutetium Lu-177 dotatate share the octreotate peptide, uptake on the diagnostic scan predicts whether a tumor can take up the therapeutic analog. In the Vanderbilt comparison study, 68Ga-DOTATATE PET/CT correctly identified three patients as candidates for peptide receptor radionuclide therapy whom 111In-pentetreotide imaging had misclassified (Deppen et al., Journal of Nuclear Medicine, 2016, 57(5):708-714).
• Receptor competition. Octreotide and lanreotide, given unlabeled, occupy the same receptors and can reduce tracer uptake, and repeated high doses of glucocorticoids can downregulate SSTR2 enough to cause false-negative scans (FDA label, Drug Interactions and Warnings sections). The converse also holds: any tissue with somatostatin receptors, including spleen, pituitary, adrenal glands, the uncinate process of the pancreas and inflammatory or other tumor types, can light up without being a neuroendocrine tumor.

Research status

Gallium Ga-68 dotatate has an unusual evidence base for an approved drug: much of it was generated by academic centers in Europe and Australia before any company sought approval, and the US application rested on one new prospective study plus two published ones.

Studies in the US label. Study A enrolled 97 adults with known or suspected NETs at a single center, with CT and/or MRI as the reference standard and 111In-pentetreotide imaging from within three years as the comparator; two independent readers blinded to clinical information interpreted the PET scans. Among 78 patients with both CT/MRI and 111In-pentetreotide images, PET agreed with CT/MRI in 74 (95%). Of 50 patients with NETs on CT/MRI, PET was positive in 48, including 13 whose 111In-pentetreotide scans were negative; of 28 patients with negative CT/MRI, PET was negative in 26. Study B was a published series of 104 adults with suspected NETs referenced against histopathology or clinical follow-up, read by two unblinded on-site readers, in which PET was positive in 29 of 36 patients with NETs and negative in 61 of 68 without. Study C was a published series of 63 patients evaluated for recurrence with two blinded central readers, who correctly identified 23 and 22 of 29 patients with recurrence and 29 and 32 of 34 without. None of the three studies included pediatric patients; the pediatric indication rests on extrapolation from adults, receptor-binding data and a published pediatric study (FDA label, Clinical Studies and Use in Specific Populations sections).

The Vanderbilt comparison. Deppen et al. (Journal of Nuclear Medicine, 2016, 57(5):708-714) reported the prospective study behind Study A. 68Ga-DOTATATE PET/CT and 111In-pentetreotide scans were obtained in 78 of 97 consecutively enrolled patients with pulmonary or gastroenteropancreatic NETs. The two methods differed significantly in their impact on treatment (p < 0.001); PET/CT combined with CT or liver MRI changed care in 28 of 78 patients (36%). Interobserver agreement between blinded and nonblinded readers was high, and the only events recorded were mild (tachycardia in one patient, a transaminase rise in one and hyperglycemia in two). The authors concluded that 68Ga-DOTATATE PET/CT was equivalent or superior to 111In-pentetreotide in every patient and should replace it where available.

The NIH cohort. Sadowski et al. (Journal of Clinical Oncology, 2016, 34(6):588-596) prospectively imaged 131 patients with 68Ga-DOTATATE PET/CT, 111In-pentetreotide SPECT/CT and anatomic imaging. PET/CT detected 95.1% of lesions (95% confidence interval 92.4% to 96.8%) versus 30.9% for 111In-pentetreotide SPECT/CT and 45.3% for anatomic imaging, and its findings changed the management recommendation in 43 of 131 patients (32.8%). In patients with carcinoid symptoms but negative biochemical testing, PET/CT found lesions in 65.2%. The National Cancer Institute’s registered Phase 2 study of the agent (NCT01967537), run at the NIH Clinical Center by the same group, enrolled 341 participants between October 18, 2013 and March 12, 2018 and is listed as completed.

Meta-analyses. Pooled accuracy estimates have been stable across a decade of reviews. Treglia et al. (Endocrine, 2012, 42(1):80-87) pooled 16 studies and 567 patients of gallium-68 somatostatin receptor PET in thoracic and gastroenteropancreatic NETs and found per-patient sensitivity of 93% (95% CI 91% to 95%) and specificity of 91% (95% CI 82% to 97%). Geijer and Breimer (European Journal of Nuclear Medicine and Molecular Imaging, 2013, 40(11):1770-1780) updated that analysis to 22 studies and 2,105 patients: sensitivity 93% (95% CI 91% to 94%), specificity 96% (95% CI 95% to 98%), area under the summary ROC curve 0.98. Yang et al. (Acta Radiologica, 2014, 55(4):389-398) separated the tracers across 10 studies and 416 patients and found per-patient sensitivity of 96% for 68Ga-DOTATATE versus 93% for 68Ga-DOTATOC, with the DOTATATE specificity estimate of 100% resting on a wide interval (82% to 100%) and few studies. The review most directly tied to the US approval, Deppen et al. (Journal of Nuclear Medicine, 2016, 57(6):872-878), screened 2,479 articles, found 42 eligible and estimated sensitivity of 90.9% (95% CI 81.4% to 96.4%) and specificity of 90.6% (95% CI 77.8% to 96.1%) against conventional imaging; harm possibly related to the tracer was rare (6 of 974 patients) and no study reported major toxicity. The same review noted that no direct comparison with octreotide scintigraphy in an unbiased population had been published, a gap the Vanderbilt and NIH studies were designed to address.

Later agents using the same target. 68Ga-DOTATOC (edotreotide), which differs from dotatate by one amino acid at the C-terminus, was approved by the FDA on August 21, 2019 under an application from the University of Iowa Health Care PET Imaging Center (NDA 210828). Copper Cu-64 dotatate (Detectnet) was approved on September 3, 2020 for adults, on the strength of a reader-masked trial in 42 NET patients and 21 healthy volunteers that reported 90.9% sensitivity and 96.6% specificity (Delpassand et al., Journal of Nuclear Medicine, 2020, 61(6):890-896); its 12.7-hour half-life allows central manufacture and shipping, which gallium-68’s 68 minutes do not.

Regulatory record. The FDA approved NETSPOT (NDA 208547) on June 1, 2016 as a new molecular entity with priority review and orphan drug designation. The label has been revised through labeling supplements, most recently approved October 26, 2023, and the current prescribing information carries an October 2023 revision date. No new indication, new sponsor or follow-on gallium Ga 68 dotatate product had been approved in the United States as of November 2026. Supply depends on gallium-68 eluted from the two germanium-68/gallium-68 generators named in the label (Eckert & Ziegler GalliaPharm and IRE ELiT Galli Eo), and generator availability constrained access in the years after approval.

Active work. ClinicalTrials.gov lists more than 60 recruiting or active studies involving 68Ga-DOTATATE as of November 2026. Few of these test the diagnostic itself; most use it as the patient-selection or response-assessment tool inside trials of radioligand therapy, including the NETTER-3 study (NCT06784752) of lutetium Lu-177 dotatate, actinium-225 somatostatin analogs and combinations, or evaluate it in tumors outside the label such as meningioma, pheochromocytoma and paraganglioma, medullary thyroid cancer and neuroblastoma.

Common dosage forms

• NETSPOT. A two-vial kit for the preparation of gallium Ga 68 dotatate injection, consisting of a reaction vial of 40 mcg dotatate and a buffer vial, labeled with gallium-68 on site.
• No other presentation. No ready-to-use gallium Ga-68 dotatate injection is marketed; the finished product exists only after on-site labeling.

Key considerations

• Regulatory status. The FDA Approved status reflects the June 1, 2016 approval of NETSPOT (NDA 208547) for PET localization of somatostatin receptor-positive neuroendocrine tumors in adult and pediatric patients. It is prepared and administered only in licensed nuclear medicine facilities and has no role outside imaging.
• A localization tool, not a diagnosis. Uptake reflects somatostatin receptor density, so positive findings may need histopathological confirmation, and receptor expression in other tumor types, splenosis, inflammatory tissue and normal structures can mimic a NET. A negative scan does not exclude a NET, and poorly differentiated neuroendocrine carcinomas often lose SSTR2 and can escape detection.
• Evidence shape. Sensitivity and specificity cluster around 90% to 96% across four meta-analyses, but the underlying studies are heterogeneous single-center series with varying reference standards, and the pivotal studies compared against CT/MRI or clinical follow-up rather than universal pathology. Pediatric efficacy is extrapolated from adults.
• Safety signals. No serious adverse reactions were identified in the clinical studies; postmarketing reports include nausea, vomiting, injection-site pain and hypersensitivity reactions up to anaphylaxis, and the agent adds to cumulative radiation exposure. Long-acting somatostatin analogs and repeated high-dose glucocorticoids can distort results through receptor competition or downregulation.
• Naming. NETSPOT, 68Ga-DOTATATE, Ga-68 DOTATATE, gallium Ga 68 dotatate and gallium-68 oxodotreotide all describe the same drug, while 68Ga-DOTATOC (edotreotide) and 64Cu-DOTATATE (Detectnet) are different approved products that share the target. Lutetium Lu-177 dotatate is the therapeutic partner, not an imaging agent, and results reported for one tracer do not transfer to another without a head-to-head study.