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Use of bone-seeking radiopharmaceuticals is an established modality in the palliative care of pain due to skeletal metastases. 177 Lu-DOTMP is a promising radiopharmaceutical for this application owing to the ideally suited decay properties of 177 Lu and excellent thermodynamic stability and kinetic rigidity of the macrocyclic complex. The aim of the present study is to develop a robust and easily adaptable protocol for formulation of clinical doses of 177 Lu-DOTMP at hospital radiopharmacy. After extensive radiochemical studies, an optimized strategy for formulation of clinical doses of 177 Lu-DOTMP was developed, which involves simple mixing of approximately 3.7 GBq of 177 Lu activity as 177 LuCl 3 solution to an aqueous solution containing 5 mg of DOTMP and 8 mg of NaHCO 3 . The proposed protocol yielded 177 Lu-DOTMP with >98% radiochemical purity, and the resultant formulation showed excellent in vitro stability and desired pharmacokinetic properties in animal model. Preliminary clinical investigations in 5 patients showed specific skeletal accumulation with preferential localization in the osteoblastic lesion sites and almost no uptake in soft tissue or any other major nontarget organ. The developed "mix-and-use" strategy would be useful for large number of nuclear medicine centers having access to 177 Lu activity and would thereby accelerate the clinical translation of 177 Lu-DOTMP., (Copyright © 2017 John Wiley & Sons, Ltd.)

Objective: The objective of the present work was to develop a freeze-dried ethylenediaminetetramethylene phosphonic acid (EDTMP) kit, suitable for the convenient and single-step preparation of (177)Lu-EDTMP, which is currently being evaluated as a promising radiopharmaceutical for providing palliative care to patients suffering from skeletal metastases and to assess the potential of the agent in human patients., Experimental: Lyophilized EDTMP kits having identical composition with Quadramet(®) were prepared using EDTMP, NaOH, and anhydrous CaCO3. The (177)Lu-EDTMP patient dose was prepared by incubating the kit materials dissolved in 1 mL of water for injection and (177)LuCl3, produced in-house, at room temperature for 15 minutes. Pharmacokinetic behavior of the agent was studied by carrying out biodistribution and scintigraphic imaging studies in normal Wistar rats. Clinical studies were performed by administering the preparation in patients suffering from disseminated skeletal metastases., Results: Five batches of freeze-dried EDTMP kits with 50 kit vials in each batch were prepared. Each kit vial comprised a lyophilized mixture of 35 mg EDTMP, 14.1 mg NaOH, and 5.8 mg of CaCO3. The (177)Lu-EDTMP complex was prepared with excellent radiochemical purity (>99%) and high stability (>98% until 9 days postpreparation) using these kits. Radiochemical studies showed that this kit could be used within a pH range of 6-9 and with (177)Lu having specific activity as low as 925 GBq · g(-1) (25 Ci · g(-1)) for the preparation of up to 3.7 GBq (100 mCi) of (177)Lu-EDTMP. Biodistribution studies in animals revealed selective accumulation of the agent in skeleton (∼ 60% of the injected activity) with major renal clearance. Preliminary clinical studies in 10 patients exhibited selective accumulation of the radiotracer in skeletal lesions and provided significant pain relief thereby improving the quality of life of the patients., Conclusion: Freeze-dried EDTMP kits, suitable for the preparation of patient doses of (177)Lu-EDTMP, have been developed and used in preliminary studies for treating the cancer patients with disseminated skeletal metastases. The kit may also find use for the preparation of other potential bone pain palliation agents, such as (153)Sm-EDTMP.

Objective: Patient dose of (177)Lu-DOTA-TATE, used for providing radiotherapeutic treatment to the patients suffering from cancers of neuroendocrine origin, could be prepared at the hospital radiopharmacy either 'in-situ' or by using freezedried kits. The objective of the present work is to formulate and evaluate a single vial freeze-dried DOTA-TATE kit, which is capable of producing up to 7.4 GBq (200 mCi) dose of (177)Lu-DOTA-TATE and to compare the two methodologies presently used for the preparation of the agent., Experimental: Freeze-dried DOTA-TATE kits, comprising a lyophilized mixture of DOTA-TATE, gentisic acid and ammonium acetate, were prepared and used for the formulation of patient doses of (177)Lu-DOTA-TATE. The kits were subjected to detailed radiochemical evaluation and the shelf-life of the kits was determined. The pharmacokinetic behavior of the agent was studied in normal Wistar rats. These kits were utilized for treating the patients suffering from various types of neuroendocrine cancers., Results: The freeze-dried kits were used for the preparation of up to 7.4 GBq (200 mCi) therapeutic doses of (177)Lu- DOTA-TATE with a radiochemical purity of >99% and were found to have sufficiently long shelf-life. Biological studies carried out in normal Wistar rats exhibited no significant accumulation of activity in any of the vital organs/tissue except in kidneys and non-accumulated activity showed major renal clearance. Clinical studies carried out in cancer patients exhibited accumulation of activity in the cancerous lesions and metastatic sites., Conclusion: The kit was useful for the convenient preparation of therapeutic dose of (177)Lu-DOTA-TATE, suitable for human administration. The use of kit is expected to reduce the batch failure and radiation exposure to the working personnel.

Purpose: Somatostatin receptor positron emission tomography/X-ray computed tomography (SSTR-PET/CT) is a well-established technique for staging and detection of neuroendocrine tumors (NETs). Ga-68-labeled DOTA-conjugated octreotide analogs are the privileged radiotracers for diagnosis and therapeutic monitoring of NETs. Hence, we were interested in assessing the influence of promising, newer variant DOTAGA on the hydrophilicity, pharmacokinetics, and lesion pick-up of somatostatin analogs. Herein, the potential of ([68Ga]DOTAGA, Tyr3, Thr8) octreotide ([68Ga]DOTAGA-TATE) and ([68Ga]DOTAGA, Tyr3) octreotide ([68Ga]DOTAGA-TOC) as NET imaging agents has been investigated.Procedures: Amenability of [68Ga]DOTAGA-(TATE/TOC) to kit-type formulation has been demonstrated. Biodistribution studies were carried out in normal rats at 1 h post-injection (p.i.). [68Ga]DOTAGA-(TATE/TOC) PET/CT scans were carried out in patients (70-170 MBq, 1 h p.i.) with histologically confirmed well-differentiated NETs.Results: [68Ga]DOTAGA-TATE exhibited hydrophilicity similar to [68Ga]DOTA-TATE (log P = -3.51 vs -3.69) whereas [68Ga]DOTAGA-TOC was more hydrophilic than [68Ga]DOTA-TOC (log P = -3.27 vs -2.93). [68Ga]DOTAGA-TATE and [68Ga]DOTA-TATE showed almost identical blood and kidney uptake in normal rats whereas significantly fast clearance (p < 0.05) of [68Ga]DOTAGA-TATE was observed from other non-specific organs (liver, lungs, spleen, intestine). [68Ga]DOTAGA-TOC also demonstrated rapid clearance from blood and kidneys (p < 0.05) in comparison to [68Ga]DOTA-TOC. The metastatic lesions in NET patients were well identified by [68Ga]DOTAGA-TATE and [68Ga]DOTAGA-TOC.Conclusion: The phenomenal analogy was observed between [68Ga]DOTAGA-TATE and [68Ga]DOTA-TATE as well as between [68Ga]DOTAGA-TOC and [68Ga]DOTA-TOC in biodistribution studies in rats. The good lesion detection ability of the two radiotracers indicates their potential as NET imaging radiotracers. [ABSTRACT FROM AUTHOR]

Purpose: [(68)Ga]DKFZ-PSMA-11 has proved to be an important diagnostic radiotracer for targeting prostate-specific membrane antigen (PSMA) overexpression in both recurrent prostate cancer (PC) and relevant metastatic sites. However, the widespread, routine clinical use of such a potential radiopharmaceutical demands availability of a ready-to-use kit formulation to enable convenient radiopharmaceutical preparation. Herein, we report the development of a freeze-dried kit vial for the formulation of [(68)Ga]DKFZ-PSMA-11 and its clinical use in patients using a "shake-bake-inject" methodology.Procedures: The freeze-dried kit vial was developed after optimization of ligand content (PSMA-11) and pH conditions. The kit was formulated using (68)Ga from two different commercially available generators. Positron emission tomography/X-ray computed tomography (PET/CT) images of PC patients were obtained using the kit-formulated radiotracer.Results: [(68)Ga]DKFZ-PSMA-11 was prepared in >98 % radiochemical yield and purity using the freeze-dried kit vials. Kits were optimized for the preparation of four patient doses. The clinical utility was evaluated in patients with histologically confirmed prostate cancer, and the images were of good quality as well as conforming to tumor marker and clinical expectations.Conclusion: The development of a simple and ready-to-use freeze-dried DKFZ-PSMA-11 kit for the preparation of Ga-68-based radiotracers constitutes a major step towards the expedition of the widespread and economical screening of PC patients. [ABSTRACT FROM AUTHOR]

Extra-adrenal retroperitoneal paragangliomas (PGLs) are rare tumors causing considerable difficulty in both, diagnosis and treatment. They can be unicentric or multicentric, tend to be locally invasive and therefore have a high incidence of local recurrence. PGLs shows somatostatin receptor positivity, which can be imaged with technetium-99m (Tc-99m)-hydrazinonicotinyl-Tyr3-octreotide (HYNIC-TOC) and can be treated with lutetium-177 (Lu-177) DOTATATE. We present a case of recurrent unresectable retroperitoneal PGL with nodal and bone metastases in a 27-year-old male, 6 months postsurgery detected with Tc-99m-HYNIC-TOC and was administered with peptide receptor radionuclide therapy using Lu-177 DOTATATE. [ABSTRACT FROM AUTHOR]

While radiation synovectomy (RSV) constitutes a successful paradigm for the treatment of arthritis, a major cornerstone of its success resides in the selection of appropriate radiolabeled agent. Among the radionuclide used for RSV, the scope of using 177Lu [ T1/2 = 6.65 d, E β(max) = 497 keV, Eγ = 113 KeV (6.4%), 208 KeV (11%)] seemed to be attractive owing to its suitable decay characteristics, easy availability, and cost-effective production route. The present article describes a formulation of 177Lu-labeled hydroxyapatite (HA) using ready-to-use kits of HA particles of 1-10 µm size range. The developed kits enable convenient one-step preparation of 177Lu-HA (400 ± 30 MBq doses) in high radiochemical purity (>99%) and stability at hospital radiopharmacy. The preparation showed promising results in pre-clinical studies carried out in Wistar rats bearing arthritis in knee joints. In preliminary clinical investigation, significant improvement in the disease conditions was reported in 10 patients with rheumatoid arthritis of knee joints treated with 333 ± 46 MBq doses of 177Lu-HA. The studies reveal that while 177Lu labeled HA particles holds considerable promise as a cost-effective agent for RSV, the adopted strategy of using HA kits could be a potential step toward wider clinical utilization of radiolanthanide-labeled HA particles. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Rhenium-188(188Re)-lipiodol is a clinically effective, economically viable radiopharmaceutical for Selective Internal Radiation Therapy of liver cancer. Present study evaluates the performance of three freeze-dried kits with respect to the radiochemistry, quality control, and overall "ease of preparation" aspects in a hospital radiopharmacy. Materials and Methods: Freeze-dried kits of acetylated 4-hexadecyl-4,7-diaza-1,10-decanedithiol (AHDD), super six sulfur (SSS), and diethyl dithiocarbamate (DEDC), obtained commercially or received as gift, were used for the preparation of 188Re-lipiodol using freshly eluted 188Re-sodium perrhenate from commercial Tungsten-188/188Re generator following recommended procedures. Results: The overall yield of 188Re-lipiodol prepared using AHDD Kit, SSS Kit, and DEDC Kit was 74.82% ± 3.3%, 87.55% ± 4.8%, and 76.38% ± 4.6%, respectively. Observed radiochemical purity (RCP) of 188Re-lipiodol prepared using these kits was 88.65% ± 2.8%, 92.92% ± 3.0%, and 91.38% ± 3.0%, respectively. Using a modified version of the DEDC Kits, overall yield of 87.17% ± 2.7% and RCP of 95.43% ± 2.3% could be achieved. Conclusions: While all three freeze-dried kits can be used for the preparation of 188Re-lipiodol in >70% overall yield, the modified version of DEDC Kits has some advantages in terms of preparation time and volume of Rhenium-188 activity that can be added to the kit vial. The latter feature of the DEDC Kit is particularly useful for patient dose preparation with 188Re activity of low radioactive concentration. [ABSTRACT FROM AUTHOR]