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Dosimetry Based PRRT Versus Standard Dose PRRT With Lu-177-DOTATOC in NEN Patients

Dosimetry Based PRRT Versus Standard Dose PRRT With Lu-177-DOTATOC in NEN Patients- a Randomized Study; a Step Towards Tailored PRRT

Status
Recruiting
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04917484
Acronym
DOBATOC
Enrollment
100
Registered
2021-06-08
Start date
2020-02-01
Completion date
2026-12-31
Last updated
2024-12-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Neuroendocrine Neoplasm

Keywords

Peptide receptor radionuclide therapy, Dosimetry

Brief summary

In this study, we want to randomize patients with neuroendocrine neoplasms (NENs) who are eligible for peptide receptor radionuclide therapy (PRRT), to either standard PRRT consisting of 4 treatments with 7.4 GBq Lu-177-DOTATOC (standard arm) or 4 treatments with individualized doses of Lu-177-DOTATOC (dosimetry arm). In the dosimetry arm, the first dose depends on the patients' kidney function and thereafter the absorbed dose to the kidneys at the previous treatment. A max of 20GBq will be administered at the first treatment and 25GBq at treatment 2-4. We aim to reach an accumulated kidney dose of 24Gy. After the first treatment all patients will go through three SPECT/CT scans 24 hours, 4 days, and 7 days, after treatment to calculate absorbed kidney dose. The patients in the standard dose treatment arm will have one SPECT/CT scan after each of the last three treatments; all performed 24 hours after treatment, used to approximate the kidney dose assuming the clearance of the Lu-177 DOTATOC is the same after all treatments. The patients in the dosimetry based treatment arm will go through three SPECT/CT scans after all four treatments for dosimetry calculation. Bone marrow dosimetry is calculated after all treatments in the dosimetry based treatment arm and after the first treatment in the standard treatment arm. For bone marrow dosimetry, blood samples are drawn right before administration of Lu-177 DOTATOC (time 0) and 3 minutes, 45 minutes, 2 hours, 4 hours, 7-8 hours, 24 hours, 4 days, and 7 days after administration of Lu-177 DOTATOC. Standard blood samples are routinely drawn every 2nd week after every treatment in all included patients and analysed regarding liver, kidney and bone marrow function. Kidney clearance is evaluated with Tc-DTPA clearance at baseline. Blood and urinary samples will be collected at baseline and 3 months after the last treatment for kidney fibrosis analyses. At baseline, blood and urine samples are collected for a biobank. All included patients fill in validated quality of life questionaires at all treatments. To evaluate the effect of the treatment, all patients will be evaluated with standard CT scans prior to treatment and 3 and 9 months after the 4th treatment. Ga-68 DOTATOC PET will be performed at baseline and 6 and 12 months after the last treatment.

Interventions

DRUGLu-177-DOTA-Octreotide

Lu-177-DOTATOC in standard doses or individualized doses.

Sponsors

Tine Gregersen, MD
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

Randomized, non blinded

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* 1\. Male or female patients 18 years of age or more * 2\. NEN confirmed by histology * 3\. Clinical, PET/CT or CT proven progression despite standard treatment with somatostatin analogues, targeted therapy (Everolimus, sunitinib), chemotherapy (STZ/5-FU, temozolomide/capecitabine) OR intolerable side effects caused by these standard treatment OR unmanageable carcinoid symptoms * 4\. WHO/ ECOG Performance Status of 0-2 * 5\. Life expectancy more than 6 months * 6\. Uptake higher than liver in primary tumor or metastases on Ga-DOTATOC PET/CT (Krenning 3 or 4), if the scan is more than 3 months old at inclusion time, a new scan should be done. * 7\. Adequate organ function as defined by: * Adequate kidney function: Patient glomerular filtration rate \>30 ml/min measured by Tc-DTPA clearance * Adequate bone marrow function: * WBC ≥ 2.0 x 109/L * Platelets ≥ 100 x 109/L * Hb ≥ 6 mmol/l (≥9.67 g/dL) * 8\. Willingness and ability to comply with scheduled visits for SPECT/CT scans, treatment plans, laboratory tests and other study procedures. 9\. Written informed consent obtained prior to any screening procedures

Exclusion criteria

* 1\. Tumor amenable to surgery and/or radiofrequency ablation * 2\. Patients who are unable to stay isolated for 24 hours * 3\. Previous PRRT * 4\. Female patients who are pregnant or lactating. Women who are of childbearing potential (defined as all women physiologically capable of becoming pregnant) have to practice an effective method of contraception/birth control. Fertile female patients have to take a urinary pregnancy test, to ensure that they are not pregnant, before they can enter the study. After entering the study, they have to use effective contraception during the study period and 6 months after. Effective contraception methods include: * Use of oral, injected or implanted hormonal methods of contraception or * Placement of an intrauterine device (IUD) or intrauterine system (IUS) * Total abstinence or patient sterilization (male or female) * 5\. Male patients are not allowed to conceive pregnancy for 6 months after last treatment cycle * 6\. Known to be hypersensitive to any component of the Lu-177-DOTATOC * 7\. Patients with meningioma

Design outcomes

Primary

MeasureTime frameDescription
Progression free survival12 months after LPLVDefined as time from randomization to documented disease progression or death by any cause, evaluated by CT, RECIST 1.1.

Secondary

MeasureTime frameDescription
Tumor doseThrough out the study efter each patient has completed treatment, up to 48 weeksDifference in tumor dose between dosimetry based and standard PRRT treatment groups and between patients in the dosimetry based treatment group over time.

Other

MeasureTime frameDescription
Subjective side effectsAfter every treatment, up to 48 weeksEvaluated by use of dedicated questionaire with score from 0-3
Kidney toxicityAt baseline and after 3, 6 and 12 monthsMeasured by Tc-DTPA clearance
Bone marrow function, hemoglobinEvery second week in up to 64 weeksMeasured by hemoglobin in the two groups
Quality of life score 1After every treatment, up to 48 weeksEvaluated by questionnaire EORTC QLQ-30 filled out at every treatment
Quality of life score 2After every treatment, up to 48 weeksEvaluated by questionnaire QLQ-GI.NET21. filled out at every treatment
Overall survival3 years after LPLVRegistration of time for baseline to death
Bone marrow function, white blood cellsEvery second week in up to 64 weeksMeasured by white blood cells in the two groups
Bone marrow function, plateletsEvery second week in up to 64 weeksMeasured by platelets in the two groups

Countries

Denmark

Contacts

Primary ContactTine N Gregersen, MD, PhD
tigreg@rm.dk+4522334161

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026