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Frontiers in Medicine 2022Osteosarcoma is a high-grade sarcoma characterized by osteoid formation, nearly universal expression of IGF1R and with a subset expressing HER-2. These qualities provide... (Review)
Review
Osteosarcoma is a high-grade sarcoma characterized by osteoid formation, nearly universal expression of IGF1R and with a subset expressing HER-2. These qualities provide opportunities for the use of the alpha particle-emitting isotopes to provide targeted radiation therapy alpha particles precisely to bone-forming tumors in addition to IFG1R or Her-2 expressing metastases. This review will detail experience using the alpha emitter radium-223 (Ra, tradename Xofigo), that targets bone formation, in osteosarcoma, specifically related to patient selection, use of gemcitabine for radio-sensitization, and using denosumab to increasing the osteoblastic phenotype of these cancers. A case of an inoperable left upper lobe vertebral-paraspinal-mediastinal osteoblastic lesion treated successfully with Ra combined with gemcitabine is described. Because not all areas of osteosarcoma lesions are osteoblastic, but nearly all osteosarcoma cells overexpress IGF1R, and some subsets expressing Her-2, the anti-IGF1R antibody FPI-1434 linked to actinium-225 (Ac) or the Her-2 antibody linked to thorium-227 (Th) may become other means to provide targeted alpha particle therapy against osteosarcoma (NCT03746431 and NCT04147819).
PubMed: 36457575
DOI: 10.3389/fmed.2022.1030094 -
International Journal of Molecular... Feb 2015This paper reviews some aspects and recent developments in the use of antibodies to target radionuclides for tumor imaging and therapy. While radiolabeled antibodies... (Review)
Review
This paper reviews some aspects and recent developments in the use of antibodies to target radionuclides for tumor imaging and therapy. While radiolabeled antibodies have been considered for many years in this context, only a few have reached the level of routine clinical use. However, alternative radionuclides, with more appropriate physical properties, such as lutetium-177 or copper-67, as well as alpha-emitting radionuclides, including astatine-211, bismuth-213, actinium-225, and others are currently reviving hopes in cancer treatments, both in hematological diseases and solid tumors. At the same time, PET imaging, with short-lived radionuclides, such as gallium-68, fluorine-18 or copper-64, or long half-life ones, particularly iodine-124 and zirconium-89 now offers new perspectives in immuno-specific phenotype tumor imaging. New antibody analogues and pretargeting strategies have also considerably improved the performances of tumor immunotargeting and completely renewed the interest in these approaches for imaging and therapy by providing theranostics, companion diagnostics and news tools to make personalized medicine a reality.
Topics: Antibodies, Monoclonal; Diagnostic Imaging; Humans; Neoplasms; Radioimmunotherapy; Radioisotopes; Radionuclide Imaging
PubMed: 25679452
DOI: 10.3390/ijms16023932 -
Science Translational Medicine Jul 2023T cells are the central drivers of many inflammatory diseases, but the repertoire of tissue-resident T cells at sites of pathology in human organs remains poorly...
T cells are the central drivers of many inflammatory diseases, but the repertoire of tissue-resident T cells at sites of pathology in human organs remains poorly understood. We examined the site-specificity of T cell receptor (TCR) repertoires across tissues (5 to 18 tissues per patient) in prospectively collected autopsies of patients with and without graft-versus-host disease (GVHD), a potentially lethal tissue-targeting complication of allogeneic hematopoietic cell transplantation, and in mouse models of GVHD. Anatomic similarity between tissues was a key determinant of TCR repertoire composition within patients, independent of disease or transplant status. The T cells recovered from peripheral blood and spleens in patients and mice captured a limited portion of the TCR repertoire detected in tissues. Whereas few T cell clones were shared across patients, motif-based clustering revealed shared repertoire signatures across patients in a tissue-specific fashion. T cells at disease sites had a tissue-resident phenotype and were of donor origin based on single-cell chimerism analysis. These data demonstrate the complex composition of T cell populations that persist in human tissues at the end stage of an inflammatory disorder after lymphocyte-directed therapy. These findings also underscore the importance of studying T cell in tissues rather than blood for tissue-based pathologies and suggest the tissue-specific nature of both the endogenous and posttransplant T cell landscape.
Topics: Humans; Mice; Animals; T-Lymphocytes; Hematopoietic Stem Cell Transplantation; Graft vs Host Disease; Receptors, Antigen, T-Cell
PubMed: 37494469
DOI: 10.1126/scitranslmed.abq0476 -
American Journal of Hematology Aug 2023Intensive chemotherapy with cytarabine and anthracycline (7&3) remains the standard therapy for patients medically fit for induction, but the assessment of fitness...
Intensive chemotherapy with cytarabine and anthracycline (7&3) remains the standard therapy for patients medically fit for induction, but the assessment of fitness remains controversial. Venetoclax and hypomethylating agent (ven/HMA) combination therapy has improved outcomes in unfit patients but no prospective study has assessed ven/HMA versus 7&3 as initial therapy in older, fit patients. Given no studies and expectation of ven/HMA use in patients outside of trial criteria, we evaluated retrospective outcomes among newly diagnosed patients. A nationwide electronic health record (EHR)-derived database and the University of Pennsylvania EHR identified 312 patients receiving 7&3 and 488 receiving ven/HMA who were 60-75 years old without history of organ failure. Ven/HMA patients were older and more likely to have secondary AML, adverse cytogenetics, and adverse mutations. Median overall survival (OS) for patients receiving intensive chemotherapy was 22 versus 10 months for ven/HMA (HR 0.53, 95% CI 0.40-0.60). Controlling for measured baseline characteristic imbalances reduced survival advantage by half (HR 0.71, 95% CI 0.53-0.94). A sub-group of patients with equipoise, likelihood at least 30%-70% of receiving either treatment, had similar OS outcomes (HR 1.10, 95% CI 0.75-1.6). Regarding safety outcomes, 60-day mortality was higher for ven/HMA (15% vs. 6% at 60 days) despite higher documented infections and febrile neutropenia for 7&3. In this multicenter real-word dataset, patients selected for intensive chemotherapy had superior OS but a large group had similar outcomes with ven/HMA. Prospective randomized studies, controlling for both measured and unmeasured confounders, must confirm this outcome.
Topics: Humans; Aged; Middle Aged; Retrospective Studies; Cytarabine; Bridged Bicyclo Compounds, Heterocyclic; Leukemia, Myeloid, Acute; Antineoplastic Combined Chemotherapy Protocols
PubMed: 37334852
DOI: 10.1002/ajh.26991 -
Clinical Lymphoma, Myeloma & Leukemia Oct 2023Secondary antibody deficiency (SAD) is a subtype of secondary immunodeficiency characterized by low serum antibody concentrations (hypogammaglobulinemia) or poor... (Review)
Review
Secondary antibody deficiency (SAD) is a subtype of secondary immunodeficiency characterized by low serum antibody concentrations (hypogammaglobulinemia) or poor antibody function. SAD is common in patients with multiple myeloma (MM) due to underlying disease pathophysiology and treatment-related immune system effects. Patients with SAD are more susceptible to infections and infection-related morbidity and mortality. With therapeutic advancements improving MM disease control and survival, it is increasingly important to recognize and treat the often-overlooked concurrent immunodeficiency present in patients with MM. The aims of this review are to define SAD and its consequences in MM, increase SAD awareness, and provide recommendations for SAD management. Based on expert panel discussions at a standalone meeting and supportive literature, several recommendations were made. Firstly, all patients with MM should be suspected to have SAD regardless of serum antibody concentrations. Patients should be evaluated for immunodeficiency at MM diagnosis and stratified into management categories based on their individualized risk of SAD and infection. Infection-prevention strategy education, early infection reporting, and anti-infective prophylaxis are key. We recommend prophylactic antibiotics or immunoglobulin replacement therapy (IgRT) should be considered in patients with severe hypogammaglobulinemia associated with a recurrent or persistent infection. To ensure an individualized and efficient treatment approach is utilized, patient's immunoglobin G concentration and infection burden should be closely monitored throughout treatment. Patient choice regarding route and IgRT treatment is also key in reducing treatment burden. Together, these recommendations and proposed management algorithms can be used to aid physician decision-making to improve patient outcomes.
Topics: Humans; Multiple Myeloma; Agammaglobulinemia; Immunologic Deficiency Syndromes; Immunization, Passive; Antibodies
PubMed: 37353432
DOI: 10.1016/j.clml.2023.05.008 -
EJNMMI Research Oct 2022PSMA-TO-1 ("Tumor-Optimized-1") is a novel PSMA ligand with longer circulation time than PSMA-617. We compared the biodistribution in subcutaneous tumor-bearing mice of...
BACKGROUND
PSMA-TO-1 ("Tumor-Optimized-1") is a novel PSMA ligand with longer circulation time than PSMA-617. We compared the biodistribution in subcutaneous tumor-bearing mice of PSMA-TO-1, PSMA-617 and PSMA-11 when labeled with Ga and Lu, and the survival after treatment with Ac-PSMA-TO-1/-617 in a murine model of disseminated prostate cancer. We also report dosimetry data of Lu-PSMA-TO1/-617 in prostate cancer patients.
METHODS
First, PET images of Ga-PSMA-TO-1/-617/-11 were acquired on consecutive days in three mice bearing subcutaneous C4-2 xenografts. Second, 50 subcutaneous tumor-bearing mice received either 30 MBq of Lu-PSMA-617 or Lu-PSMA-TO-1 and were sacrificed at 1, 4, 24, 48 and 168 h for ex vivo gamma counting and biodistribution. Third, mice bearing disseminated lesions via intracardiac inoculation were treated with either 40 kBq of Ac-PSMA-617, Ac-PSMA-TO-1, or remained untreated and followed for survival. Additionally, 3 metastatic castration-resistant prostate cancer patients received 500 MBq of Lu-PSMA-TO-1 under compassionate use for dosimetry purposes. Planar images with an additional SPECT/CT acquisition were acquired for dosimetry calculations.
RESULTS
Tumor uptake measured by PET imaging of Ga-labeled agents in mice was highest using PSMA-617, followed by PSMA-TO-1 and PSMA-11. Lu-PSMA tumor uptake measured by ex vivo gamma counting at subsequent time points tended to be greater for PSMA-TO-1 up to 1 week following treatment (p > 0.13 at all time points). This was, however, accompanied by increased kidney uptake and a 26-fold higher kidney dose of PSMA-TO-1 compared with PSMA-617 in mice. Mice treated with a single-cycle Ac-PSMA-TO-1 survived longer than those treated with Ac-PSMA-617 and untreated mice, respectively (17.8, 14.5 and 7.7 weeks, respectively; p < 0.0001). Kidney, salivary gland, bone marrow and mean ± SD tumor dose coefficients (Gy/GBq) for Lu-PSMA-TO-1 in patients #01/#02/#03 were 2.5/2.4/3.0, 1.0/2.5/2.3, 0.14/0.11/0.10 and 0.42 ± 0.03/4.45 ± 0.07/1.8 ± 0.57, respectively.
CONCLUSIONS
PSMA-TO-1 tumor uptake tended to be greater than that of PSMA-617 in both preclinical and clinical settings. Mice treated with Ac-PSMA-TO-1 conferred a significant survival benefit compared to Ac-PSMA-617 despite the accompanying increased kidney uptake. In humans, PSMA-TO-1 dosimetry estimates suggest increased tumor absorbed doses; however, the kidneys, salivary glands and bone marrow are also exposed to higher radiation doses. Thus, additional preclinical studies are needed before further clinical use.
PubMed: 36182983
DOI: 10.1186/s13550-022-00935-6 -
Pharmaceutics Mar 2023The widespread use of peptide receptor radionuclide therapy (PRRT) represents a major therapeutic breakthrough in nuclear medicine, particularly since the introduction... (Review)
Review
The widespread use of peptide receptor radionuclide therapy (PRRT) represents a major therapeutic breakthrough in nuclear medicine, particularly since the introduction of Lu-radiolabeled somatostatin analogs. These radiopharmaceuticals have especially improved progression-free survival and quality of life in patients with inoperable metastatic gastroenteropancreatic neuroendocrine tumors expressing somatostatin receptors. In the case of aggressive or resistant disease, the use of somatostatin derivatives radiolabeled with an alpha-emitter could provide a promising alternative. Among the currently available alpha-emitting radioelements, actinium-225 has emerged as the most suitable candidate, especially regarding its physical and radiochemical properties. Nevertheless, preclinical and clinical studies on these radiopharmaceuticals are still few and heterogeneous, despite the growing momentum for their future use on a larger scale. In this context, this report provides a comprehensive and extensive overview of the development of Ac-labeled somatostatin analogs; particular emphasis is placed on the challenges associated with the production of Ac, its physical and radiochemical properties, as well as the place of Ac-DOTATOC and Ac-DOTATATE in the management of patients with advanced metastatic neuroendocrine tumors.
PubMed: 37111537
DOI: 10.3390/pharmaceutics15041051 -
Theranostics 2020This is the initial report of an α-based pre-targeted radioimmunotherapy (PRIT) using Ac and its theranostic pair, In. We call our novel tumor-targeting DOTA-hapten...
This is the initial report of an α-based pre-targeted radioimmunotherapy (PRIT) using Ac and its theranostic pair, In. We call our novel tumor-targeting DOTA-hapten PRIT system "proteus-DOTA" or "Pr." Herein we report the first results of radiochemistry development, radiopharmacology, and stoichiometry of tumor antigen binding, including the role of specific activity, anti-tumor efficacy, and normal tissue toxicity with the Pr-PRIT approach (as α-DOTA-PRIT). A series of α-DOTA-PRIT therapy studies were performed in three solid human cancer xenograft models of colorectal cancer (GPA33), breast cancer (HER2), and neuroblastoma (GD2), including evaluation of chronic toxicity at ~20 weeks of select survivors. Preliminary biodistribution experiments in SW1222 tumor-bearing mice revealed that Ac could not be efficiently pretargeted with current DOTA-Bn hapten utilized for Lu or Y, leading to poor tumor uptake . Therefore, we synthesized Pr consisting of an empty DOTA-chelate for Ac, tethered via a short polyethylene glycol linker to a lutetium-complexed DOTA for picomolar anti-DOTA chelate single-chain variable fragment (scFv) binding. Pr was radiolabeled with Ac and its imaging surrogate, In. studies verified anti-DOTA scFv recognition of [Ac]Pr, and biodistribution and clearance studies were performed to evaluate hapten suitability and targeting efficiency. Intravenously (i.v.) administered Ac- or In-radiolabeled Pr in mice showed rapid renal clearance and minimal normal tissue retention. pretargeting studies show high tumor accumulation of Pr (16.71 ± 5.11 %IA/g or 13.19 ± 3.88 %IA/g at 24 h p.i. for [Ac]Pr and [In]Pr, respectively) and relatively low uptake in normal tissues (all average ≤ 1.4 %IA/g at 24 h p.i.). Maximum tolerated dose (MTD) was not reached for either [Ac]Pr alone or pretargeted [Ac]Pr at administered activities up to 296 kBq/mouse. Single-cycle treatment consisting of α-DOTA-PRIT with either huA33-C825 bispecific anti-tumor/anti-DOTA-hapten antibody (BsAb), anti-HER2-C825 BsAb, or hu3F8-C825 BsAb for targeting GPA33, HER2, or GD2, respectively, was highly effective. In the GPA33 model, no complete responses (CRs) were observed but prolonged overall survival of treated animals was 42 d for α-DOTA-PRIT vs. 25 d for [Ac]Pr only ( < 0.0001); for GD2, CRs (7/7, 100%) and histologic cures (4/7, 57%); and for HER2, CRs (7/19, 37%) and histologic cures (10/19, 56%) with no acute or chronic toxicity. [Ac]Pr and its imaging biomarker [In]Pr demonstrate optimal radiopharmacologic behavior for theranostic applications of α-DOTA-PRIT. For this initial evaluation of efficacy and toxicity, single-cycle treatment regimens were performed in all three systems. Histologic toxicity was not observed, so MTD was not observed. Prolonged overall survival, CRs, and histologic cures were observed in treated animals. In comparison to RIT with anti-tumor IgG antibodies, [Ac]Pr has a much improved safety profile. Ultimately, these data will be used to guide clinical development of toxicity and efficacy studies of [Ac]Pr, with the goal of delivering massive lethal doses of radiation to achieve a high probability of cure without toxicity.
Topics: Actinium; Alpha Particles; Animals; Cell Line, Tumor; Dose-Response Relationship, Radiation; Female; Half-Life; Heterocyclic Compounds, 1-Ring; Humans; Indium Radioisotopes; Mice; Nanoparticles; Neoplasms; Radioimmunotherapy; Radiopharmaceuticals; Radiotherapy Dosage; Theranostic Nanomedicine; Tissue Distribution; Toxicity Tests, Chronic; Xenograft Model Antitumor Assays
PubMed: 33052220
DOI: 10.7150/thno.48810 -
Clinical Cancer Research : An Official... May 2022The anti-CD33 antibody lintuzumab has modest activity against acute myeloid leukemia (AML). To increase its potency, lintuzumab was conjugated to actinium-225 (225Ac), a...
PURPOSE
The anti-CD33 antibody lintuzumab has modest activity against acute myeloid leukemia (AML). To increase its potency, lintuzumab was conjugated to actinium-225 (225Ac), a radionuclide yielding 4 α-particles. This first-in-human, phase I trial was conducted to determine the safety, pharmacology, and biological activity of 225Ac-lintuzumab.
PATIENTS AND METHODS
Eighteen patients (median age, 64 years; range, 45-80) with relapsed or refractory AML received a single infusion of 225Ac-lintuzumab at activities of 18.5 to 148 kBq/kg.
RESULTS
The maximum tolerated dose was 111 kBq/kg. Dose-limiting toxicities included myelosuppression lasting > 35 days in one patient receiving 148 kBq/kg and death from sepsis in two patients treated with 111 and 148 kBq/kg. Myelosuppression was the most common toxicity. Significant extramedullary toxicities were limited to transient grade 3 liver function abnormalities. Pharmacokinetics were determined by gamma counting serial whole blood, plasma, and urine samples at energy windows for the 225Ac daughters, francium-221 and bismuth-213. Two-phase elimination kinetics were seen with mean plasma t1/2 - α and t1/2 - β of 1.9 and 38 hours, respectively. Peripheral blood blasts were eliminated in 10 of 16 evaluable patients (63%) but only at doses of ≥ 37 kBq/kg. Bone marrow blasts were reduced in 10 of 15 evaluable patients (67%), including 3 patients with marrow blasts ≤ 5% and one patient with a morphologic leukemia-free state.
CONCLUSIONS
Therapy for AML with the targeted α-particle generator 225Ac-lintuzumab was feasible with an acceptable safety profile. Elimination of circulating blasts or reductions in marrow blasts were observed across all dose levels.
Topics: Actinium; Alpha Particles; Antibodies, Monoclonal, Humanized; Humans; Immunoconjugates; Leukemia, Myeloid, Acute; Middle Aged
PubMed: 35247915
DOI: 10.1158/1078-0432.CCR-21-3712 -
The Lancet. Oncology Mar 2023As the immuno-oncology field continues the rapid growth witnessed over the past decade, optimising patient outcomes requires an evolution in the current... (Review)
Review
As the immuno-oncology field continues the rapid growth witnessed over the past decade, optimising patient outcomes requires an evolution in the current response-assessment guidelines for phase 2 and 3 immunotherapy clinical trials and clinical care. Additionally, investigational tools-including image analysis of standard-of-care scans (such as CT, magnetic resonance, and PET) with analytics, such as radiomics, functional magnetic resonance agents, and novel molecular-imaging PET agents-offer promising advancements for assessment of immunotherapy. To document current challenges and opportunities and identify next steps in immunotherapy diagnostic imaging, the National Cancer Institute Clinical Imaging Steering Committee convened a meeting with diverse representation among imaging experts and oncologists to generate a comprehensive review of the state of the field.
Topics: United States; Humans; National Cancer Institute (U.S.); Neoplasms; Immunotherapy; Image Processing, Computer-Assisted; Medical Oncology
PubMed: 36858729
DOI: 10.1016/S1470-2045(22)00742-2