This is a first of many phase 1 study of Ultratrace Iobenguane I-131 (Ultratrace 131I-MIBG; Molecular Insight Pharmaceuticals, Inc., Cambridge, MA). High-specific-activity Ultratrace 131I-MIBG may provide improved efficacy and tolerability over carrier-added 131I-MIBG. We investigated the pharmacokinetics (PK), radiation dosimetry, and clinical safety in 11 patients with confirmed pheochromocytoma/paraganglioma (Pheo) or carcinoid tumors. A single 5.0-mCi (185 MBq) injection of Ultratrace 131I-MIBG, supplemented with 185 microg of unlabeled MIBG to simulate the amount of MIBG anticipated in a therapeutic dose, was administered. Over 120 hours postdose, blood and urine were collected for PK, and sequential whole-body planar imaging was performed. Patients were followed for adverse events for 2 weeks. Ultratrace 131I-MIBG is rapidly cleared from the blood and excreted in urine (80.3% +/- 2.8% of dose at 120 hours). For a therapeutic administration of 500 mCi (18.5 GBq), our estimate of the projected dose is 1.4 Gy for marrow and 10.4 Gy for kidneys. Safety results showed 12 mild adverse events, all considered unrelated to study drug, in 8 of 11 patients. These findings support the further development of Ultratrace 131I-MIBG for the treatment of neuroendocrine tumors, such as metastatic Pheo and carcinoid.

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The aim of this study is to assess the radiation absorbed dose of 18F-Fluoro-L-DOPA derived from the Positron Emission Tomography (PET) images of infants age ranging from 2 weeks– 32 weeks and a median age of 4.84 weeks (Mean 10.0 ± 10.3 weeks) with congenital hyperinsulinism.MethodsAfter injecting 25.6 ± 8.8 MBq (0.7 ± 0.2 mCi) of 18F-Fluoro-L-DOPA intravenously, three static PET scans were acquired at 20, 30, and 40 min post injection in 3-D mode on 10 patients (6 male, 4 female) with congenital hyperinsulinism. Regions of interest (ROIs) were drawn over several organs visible in the reconstructed PET/CT images and time activity curves (TACs) were generated. Residence times were calculated using the TAC data. The radiation absorbed dose for the whole body was calculated by entering the residence times in the OLINDA/EXM 1.0 software.ResultsThe mean residence times for the 18F-Fluoro-L-DOPA in the liver, lungs, kidneys, muscles, and pancreas were 11.54 ± 2.84, 1.25 ± 0.38, 4.65 ± 0.97, 17.13 ± 2.62, and 0.89 ± 0.34 min, respectively. The mean effective dose equivalent for 18F-Fluoro-L-DOPA was 0.40 ± 0.04 mSv/MBq. The CT scan used for attenuation correction delivered an additional radiation dose of 5.7 mSv. The organs receiving the highest radiation absorbed dose from 18F-Fluoro-L-DOPA were the urinary bladder wall (2.76 ± 0.95 mGy/MBq), pancreas (0.87 ± 0.30 mGy/MBq), liver (0.34 ± 0.07 mGy/MBq), and kidneys (0.61 ± 0.11 mGy/MBq). The renal system was the primary route for the radioactivity clearance and excretion.ConclusionsThe estimated radiation dose burden from 18F-Fluoro-L-DOPA is relatively modest to newborns.

Syringe pumps are commonly used to administer therapeutic 131 I-metaiodobenzylguanidine. Here we describe our recent experience with a peristaltic infusion pump system in a pediatric setting. This method can easily accommodate infusions from several vials simultaneously and is adaptable to various types of peristaltic pump. Methods: Simple off-the-shelf components are used to vent the vial: a charcoal filter, a 0.22-μm syringe filter, and a 2.54-cm (1-in) needle. The vial is connected to the primary infusion set using a male/male extension line and a 19-gauge · 8.89-cm (3.5-in) aspirating needle. With aseptic technique, the extension line is attached to the Y connector closest to the primary intravenous line leading from the saline reservoir to the infusion pump. An A-clamp is attached to the primary intravenous line, immediately before the entrance to the pump. Gravity is allowed to clear the air from the extension set and the aspirating needle. After all the air has been purged, the aspirating needle is inserted into the therapy vial using aseptic technique. The pump is programmed with the desired infusion rate and volume to be infused. Results: Twenty-one consecutive infusions have been performed to date using this method. Most of the infusions involved the use of 1 vial. On 7 occasions, 2 or 3 vials connected in series were used to successfully administer the therapy. Overestimation of the volume in the vials or of the total infusion time required can cause air to be pulled into the lines. To prevent this, the volume in the vials is equalized to 30 mL, facilitating calculation of the infusion time. If the infusion is observed over the last 2 or 3 mL and the pump stops when the air-fluid mark is about halfway up the extension set, air will be kept out of the primary infusion set. Conclusion: This method for infusing one or more vials of therapeutic radiopharmaceuticals is robust and easy to use. During infusion, the radiopharmaceutical remains in a shielded vial. Multiple vials can be connected in series to infuse the entire dose simultaneously. We describe here a method for the administration of 131 I-MIBG with a standard peristaltic infusion pump. Although there are other methods that depend on a syringe pump to infuse therapeutic radiopharmaceuticals, the peristaltic infusion pump is versatile, making it easy to perform infusions from several vials simultaneously while the radioisotope remains in its original shielding. This system is also adaptable to different types of peristaltic pumps and infusion sets.131 I-MIBG is an effective therapeutic agent commonly used in treating neuroendocrine malignancies such as neuroblastoma in a dosage range of 222 MBq/kg (6 mCi/kg) to as much as 666 MBq/kg (18 mCi/kg) (1,2). At these ranges, the total infused activity may range from 3.7 GBq (100 mCi) in children to over 44.4 GBq (1,200 mCi) in adults. But handling a high activity of 131 I-labeled products poses radiation exposure risks that need to be minimized among team members. In our facility, we use a multidisciplin...

As a medical center without a pre-existing radiopharmaceutical therapy program, it was a daunting endeavor to implement a 131I metaiodobenzylguanidine (mIBG) high-dose treatment regimen. It took several years of planning with hospital administration, vendors, and Texas Department of Health Radiological Control regulators to establish a viable program. Effective communication between physicians, nursing, nuclear medicine, environmental services, maintenance, and other support staff is essential and paramount for the successful execution and continued sustainability of the mIBG therapy program. Besides providing an effective treatment for patients, an additional goal for the program is to keep radiation exposure As Low As Reasonably Achievable (ALARA) for staff and patient caregivers. As such, start-up presented many training, logistical, and radiation safety challenges. The location of the isolation room and shielding specifications were designed to keep radiation exposure to public access areas to less than 2 microsieverts per hour. Before the first patient was treated the policies and procedures for training, radiation safety, product quality control, and infusion process needed to be developed, tested, and approved by various committees. Furthermore, a similar process was required for developing room set-up, post therapy cleanup, and waste storage procedures. Throughout the maturation process of the program, the departments involved have found that our safety culture has continually improved by the re-enforcement of knowledge and lessons learned, as both the ancillary and treatment staff grew more confident in each other’s ability during more patient treatments are performed. This article describes the process and lessons learned during the time leading up to the startup and early years of the mIBG therapy program.