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Tondo G, De Marchi F, Bonardi F, Menegon F, Verrini G, Aprile D, Anselmi M, Mazzini L, Comi C. Novel Therapeutic Strategies in Alzheimer's Disease: Pitfalls and Challenges of Anti-Amyloid Therapies and Beyond. J Clin Med 2024; 13:3098. [PMID: 38892809 PMCID: PMC11172489 DOI: 10.3390/jcm13113098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Revised: 05/21/2024] [Accepted: 05/23/2024] [Indexed: 06/21/2024] Open
Abstract
Alzheimer's disease (AD) causes a significant challenge to global healthcare systems, with limited effective treatments available. This review examines the landscape of novel therapeutic strategies for AD, focusing on the shortcomings of traditional therapies against amyloid-beta (Aβ) and exploring emerging alternatives. Despite decades of research emphasizing the role of Aβ accumulation in AD pathogenesis, clinical trials targeting Aβ have obtained disappointing results, highlighting the complexity of AD pathophysiology and the need for investigating other therapeutic approaches. In this manuscript, we first discuss the challenges associated with anti-Aβ therapies, including limited efficacy and potential adverse effects, underscoring the necessity of exploring alternative mechanisms and targets. Thereafter, we review promising non-Aβ-based strategies, such as tau-targeted therapies, neuroinflammation modulation, and gene and stem cell therapy. These approaches offer new avenues for AD treatment by addressing additional pathological hallmarks and downstream effects beyond Aβ deposition.
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Affiliation(s)
- Giacomo Tondo
- Neurology Unit, Department of Translational Medicine, Maggiore della Carità Hospital, University of Piemonte Orientale, 28100 Novara, Italy; (G.T.); (F.B.); (F.M.); (G.V.); (D.A.); (M.A.); (L.M.)
| | - Fabiola De Marchi
- Neurology Unit, Department of Translational Medicine, Maggiore della Carità Hospital, University of Piemonte Orientale, 28100 Novara, Italy; (G.T.); (F.B.); (F.M.); (G.V.); (D.A.); (M.A.); (L.M.)
| | - Francesca Bonardi
- Neurology Unit, Department of Translational Medicine, Maggiore della Carità Hospital, University of Piemonte Orientale, 28100 Novara, Italy; (G.T.); (F.B.); (F.M.); (G.V.); (D.A.); (M.A.); (L.M.)
| | - Federico Menegon
- Neurology Unit, Department of Translational Medicine, Maggiore della Carità Hospital, University of Piemonte Orientale, 28100 Novara, Italy; (G.T.); (F.B.); (F.M.); (G.V.); (D.A.); (M.A.); (L.M.)
| | - Gaia Verrini
- Neurology Unit, Department of Translational Medicine, Maggiore della Carità Hospital, University of Piemonte Orientale, 28100 Novara, Italy; (G.T.); (F.B.); (F.M.); (G.V.); (D.A.); (M.A.); (L.M.)
| | - Davide Aprile
- Neurology Unit, Department of Translational Medicine, Maggiore della Carità Hospital, University of Piemonte Orientale, 28100 Novara, Italy; (G.T.); (F.B.); (F.M.); (G.V.); (D.A.); (M.A.); (L.M.)
| | - Matteo Anselmi
- Neurology Unit, Department of Translational Medicine, Maggiore della Carità Hospital, University of Piemonte Orientale, 28100 Novara, Italy; (G.T.); (F.B.); (F.M.); (G.V.); (D.A.); (M.A.); (L.M.)
| | - Letizia Mazzini
- Neurology Unit, Department of Translational Medicine, Maggiore della Carità Hospital, University of Piemonte Orientale, 28100 Novara, Italy; (G.T.); (F.B.); (F.M.); (G.V.); (D.A.); (M.A.); (L.M.)
| | - Cristoforo Comi
- Neurology Unit, Department of Translational Medicine, Sant’Andrea Hospital, University of Piemonte Orientale, Corso Abbiate 21, 13100 Vercelli, Italy;
- Interdisciplinary Research Center of Autoimmune Diseases (IRCAD), University of Piemonte Orientale, 28100 Novara, Italy
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Penny LK, Lofthouse R, Arastoo M, Porter A, Palliyil S, Harrington CR, Wischik CM. Considerations for biomarker strategies in clinical trials investigating tau-targeting therapeutics for Alzheimer's disease. Transl Neurodegener 2024; 13:25. [PMID: 38773569 PMCID: PMC11107038 DOI: 10.1186/s40035-024-00417-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 04/24/2024] [Indexed: 05/24/2024] Open
Abstract
The use of biomarker-led clinical trial designs has been transformative for investigating amyloid-targeting therapies for Alzheimer's disease (AD). The designs have ensured the correct selection of patients on these trials, supported target engagement and have been used to support claims of disease modification and clinical efficacy. Ultimately, this has recently led to approval of disease-modifying, amyloid-targeting therapies for AD; something that should be noted for clinical trials investigating tau-targeting therapies for AD. There is a clear overlap of the purpose of biomarker use at each stage of clinical development between amyloid-targeting and tau-targeting clinical trials. However, there are differences within the potential context of use and interpretation for some biomarkers in particular measurements of amyloid and utility of soluble, phosphorylated tau biomarkers. Given the complexities of tau in health and disease, it is paramount that therapies target disease-relevant tau and, in parallel, appropriate assays of target engagement are developed. Tau positron emission tomography, fluid biomarkers reflecting tau pathology and downstream measures of neurodegeneration will be important both for participant recruitment and for monitoring disease-modification in tau-targeting clinical trials. Bespoke design of biomarker strategies and interpretations for different modalities and tau-based targets should also be considered.
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Affiliation(s)
- Lewis K Penny
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
- Scottish Biologics Facility, University of Aberdeen, Aberdeen, UK
- TauRx Therapeutics Ltd, Aberdeen, UK
| | - Richard Lofthouse
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
- Scottish Biologics Facility, University of Aberdeen, Aberdeen, UK
| | - Mohammad Arastoo
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
- Scottish Biologics Facility, University of Aberdeen, Aberdeen, UK
| | - Andy Porter
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
- Scottish Biologics Facility, University of Aberdeen, Aberdeen, UK
| | - Soumya Palliyil
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
- Scottish Biologics Facility, University of Aberdeen, Aberdeen, UK
| | - Charles R Harrington
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
- GT Diagnostics (UK) Ltd, Aberdeen, UK
- TauRx Therapeutics Ltd, Aberdeen, UK
| | - Claude M Wischik
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK.
- GT Diagnostics (UK) Ltd, Aberdeen, UK.
- TauRx Therapeutics Ltd, Aberdeen, UK.
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Gu X, Qi L, Qi Q, Zhou J, Chen S, Wang L. Monoclonal antibody therapy for Alzheimer's disease focusing on intracerebral targets. Biosci Trends 2024; 18:49-65. [PMID: 38382942 DOI: 10.5582/bst.2023.01288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. Due to the complexity of the disorder and the presence of the blood-brain barrier (BBB), its drug discovery and development are facing enormous challenges, especially after several failures of monoclonal antibody (mAb) trials. Nevertheless, the Food and Drug Administration's approval of the mAb aducanumab has ushered in a new day. As we better understand the disease's pathogenesis and identify novel intracerebral therapeutic targets, antibody-based therapies have advanced over the past few years. The mAb drugs targeting β-amyloid or hyperphosphorylated tau protein are the focus of the current research. Massive neuronal loss and glial cell-mediated inflammation are also the vital pathological hallmarks of AD, signaling a new direction for research on mAb drugs. We have elucidated the mechanisms by which AD-specific mAbs cross the BBB to bind to targets. In order to investigate therapeutic approaches to treat AD, this review focuses on the promising mAbs targeting intracerebral dysfunction and related strategies to cross the BBB.
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Affiliation(s)
- Xiaolei Gu
- College of Acupuncture and Orthopedics, Hubei University of Chinese Medicine, Wuhan, Hubei, China
| | - Long Qi
- New Drug Screening Center, Jiangsu Center for Pharmacodynamics Research and Evaluation, China Pharmaceutical University, Nanjing, China
| | - Qing Qi
- Laboratory for Reproductive Immunology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
- The Academy of Integrative Medicine of Fudan University, Shanghai, China
- Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases, Shanghai, China
| | - Jing Zhou
- Laboratory for Reproductive Immunology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
- The Academy of Integrative Medicine of Fudan University, Shanghai, China
- Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases, Shanghai, China
| | - Song Chen
- Postdoctoral Station of Xiamen University, Fujian, China
| | - Ling Wang
- Laboratory for Reproductive Immunology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China
- The Academy of Integrative Medicine of Fudan University, Shanghai, China
- Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases, Shanghai, China
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Guo X, Yan L, Zhang D, Zhao Y. Passive immunotherapy for Alzheimer's disease. Ageing Res Rev 2024; 94:102192. [PMID: 38219962 DOI: 10.1016/j.arr.2024.102192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/03/2023] [Accepted: 01/05/2024] [Indexed: 01/16/2024]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease characterized by cognitive impairment with few therapeutic options. Despite many failures in developing AD treatment during the past 20 years, significant advances have been achieved in passive immunotherapy of AD very recently. Here, we review characteristics, clinical trial data, and mechanisms of action for monoclonal antibodies (mAbs) targeting key players in AD pathogenesis, including amyloid-β (Aβ), tau and neuroinflammation modulators. We emphasized the efficacy of lecanemab and donanemab on cognition and amyloid clearance in AD patients in phase III clinical trials and discussed factors that may contribute to the efficacy and side effects of anti-Aβ mAbs. In addition, we provided important information on mAbs targeting tau or inflammatory regulators in clinical trials, and indicated that mAbs against the mid-region of tau or pathogenic tau have therapeutic potential for AD. In conclusion, passive immunotherapy targeting key players in AD pathogenesis offers a promising strategy for effective AD treatment.
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Affiliation(s)
- Xiaoyi Guo
- Center for Brain Sciences, the First Affiliated Hospital of Xiamen University, Institute of Neuroscience, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, School of Medicine, Xiamen University, Xiamen, Fujian 361005, China
| | - Li Yan
- School of Traditional Chinese Medicine, Jinan University, 601 Huangpu Avenue West, Guangzhou, Guangdong 510632, China
| | - Denghong Zhang
- Center for Brain Sciences, the First Affiliated Hospital of Xiamen University, Institute of Neuroscience, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, School of Medicine, Xiamen University, Xiamen, Fujian 361005, China
| | - Yingjun Zhao
- Center for Brain Sciences, the First Affiliated Hospital of Xiamen University, Institute of Neuroscience, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, School of Medicine, Xiamen University, Xiamen, Fujian 361005, China.
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5
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Aljassabi A, Zieneldien T, Kim J, Regmi D, Cao C. Alzheimer's Disease Immunotherapy: Current Strategies and Future Prospects. J Alzheimers Dis 2024; 98:755-772. [PMID: 38489183 DOI: 10.3233/jad-231163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2024]
Abstract
Alzheimer's disease (AD) is an extremely complex and heterogeneous pathology influenced by many factors contributing to its onset and progression, including aging, amyloid-beta (Aβ) plaques, tau fibril accumulation, inflammation, etc. Despite promising advances in drug development, there is no cure for AD. Although there have been substantial advancements in understanding the pathogenesis of AD, there have been over 200 unsuccessful clinical trials in the past decade. In recent years, immunotherapies have been at the forefront of these efforts. Immunotherapy alludes to the immunological field that strives to identify disease treatments via the enhancement, suppression, or induction of immune responses. Interestingly, immunotherapy in AD is a relatively new approach for non-infectious disease. At present, antibody therapy (passive immunotherapy) that targets anti-Aβ aimed to prevent the fibrillization of Aβ peptides and disrupt pre-existing fibrils is a predominant AD immunotherapy due to the continuous failure of active immunotherapy for AD. The most rational and safe strategies will be those targeting the toxic molecule without triggering an abnormal immune response, offering therapeutic advantages, thus making clinical trial design more efficient. This review offers a concise overview of immunotherapeutic strategies, including active and passive immunotherapy for AD. Our review encompasses approved methods and those presently under investigation in clinical trials, while elucidating the recent challenges, complications, successes, and potential treatments. Thus, immunotherapies targeting Aβ throughout the disease progression using a mutant oligomer-Aβ stimulated dendritic cell vaccine may offer a promising therapy in AD.
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Affiliation(s)
- Ali Aljassabi
- Department of Pharmaceutical Science, Taneja College of Pharmacy, University of South Florida, Tampa, FL, USA
| | - Tarek Zieneldien
- Department of Pharmaceutical Science, Taneja College of Pharmacy, University of South Florida, Tampa, FL, USA
| | - Janice Kim
- Department of Pharmaceutical Science, Taneja College of Pharmacy, University of South Florida, Tampa, FL, USA
| | - Deepika Regmi
- Department of Pharmaceutical Science, Taneja College of Pharmacy, University of South Florida, Tampa, FL, USA
| | - Chuanhai Cao
- Department of Pharmaceutical Science, Taneja College of Pharmacy, University of South Florida, Tampa, FL, USA
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Congdon EE, Ji C, Tetlow AM, Jiang Y, Sigurdsson EM. Tau-targeting therapies for Alzheimer disease: current status and future directions. Nat Rev Neurol 2023; 19:715-736. [PMID: 37875627 PMCID: PMC10965012 DOI: 10.1038/s41582-023-00883-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2023] [Indexed: 10/26/2023]
Abstract
Alzheimer disease (AD) is the most common cause of dementia in older individuals. AD is characterized pathologically by amyloid-β (Aβ) plaques and tau neurofibrillary tangles in the brain, with associated loss of synapses and neurons, which eventually results in dementia. Many of the early attempts to develop treatments for AD focused on Aβ, but a lack of efficacy of these treatments in terms of slowing disease progression led to a change of strategy towards targeting of tau pathology. Given that tau shows a stronger correlation with symptom severity than does Aβ, targeting of tau is more likely to be efficacious once cognitive decline begins. Anti-tau therapies initially focused on post-translational modifications, inhibition of tau aggregation and stabilization of microtubules. However, trials of many potential drugs were discontinued because of toxicity and/or lack of efficacy. Currently, the majority of tau-targeting agents in clinical trials are immunotherapies. In this Review, we provide an update on the results from the initial immunotherapy trials and an overview of new therapeutic candidates that are in clinical development, as well as considering future directions for tau-targeting therapies.
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Affiliation(s)
- Erin E Congdon
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Changyi Ji
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Amber M Tetlow
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Yixiang Jiang
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY, USA.
- Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA.
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY, USA.
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Shulman M, Kong J, O'Gorman J, Ratti E, Rajagovindan R, Viollet L, Huang E, Sharma S, Racine AM, Czerkowicz J, Graham D, Li Y, Hering H, Haeberlein SB. TANGO: a placebo-controlled randomized phase 2 study of efficacy and safety of the anti-tau monoclonal antibody gosuranemab in early Alzheimer's disease. NATURE AGING 2023; 3:1591-1601. [PMID: 38012285 PMCID: PMC10724064 DOI: 10.1038/s43587-023-00523-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 10/10/2023] [Indexed: 11/29/2023]
Abstract
In Alzheimer's disease, the spread of aberrantly phosphorylated tau is an important criterion in the Braak staging of disease severity and correlates with disease symptomatology. Here, we report the results of TANGO ( NCT03352557 ), a randomized, double-blind, placebo-controlled, parallel-group and multiple-dose long-term trial of gosuranemab-a monoclonal antibody to N-terminal tau-in patients with early Alzheimer's disease. The primary objective was to assess the safety and tolerability of gosuranemab compared to placebo. The secondary objectives were to assess the efficacy of multiple doses of gosuranemab in slowing cognitive and functional impairment (using the Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) scores at week 78) and evaluate the immunogenicity of gosuranemab (using the incidence of anti-gosuranemab antibody responses). Participants were randomized (n = 654); received (n = 650) low-dose (125 mg once every 4 weeks (q4w), n = 58; 375 mg q12w, n = 58), intermediate-dose (600 mg q4w, n = 106) or high-dose (2,000 mg q4w, n = 214) gosuranemab or placebo (q4w, n = 214) intravenously for 78 weeks; and assigned to cerebrospinal fluid (n = 327) and/or tau positron emission tomography (n = 357) biomarker substudies. Gosuranemab had an acceptable safety profile and was generally well tolerated (incidence of serious adverse events: placebo, 12.1%; low dose, 10.3%; intermediate dose, 12.3%; high dose, 11.7%). The incidence of treatment-emergent gosuranemab antibody responses was low at all time points. No significant effects were identified in cognitive and functional tests as no dose resulted in a favorable change from the baseline CDR-SB score at week 78 compared to placebo control (adjusted mean change: placebo, 1.85; low dose, 2.20; intermediate dose, 2.24; high dose, 1.85). At week 76, all doses caused significant (P < 0.0001) reductions in the cerebrospinal fluid levels of unbound N-terminal tau compared to placebo.
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Affiliation(s)
| | | | | | - Elena Ratti
- Biogen, Cambridge, MA, USA
- Takeda Pharmaceuticals, Cambridge, MA, USA
| | | | - Louis Viollet
- Biogen, Cambridge, MA, USA
- Moderna, Cambridge, MA, USA
| | | | | | - Annie M Racine
- Biogen, Cambridge, MA, USA
- Alexion, AstraZeneca Rare Disease, Boston, MA, USA
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Chen Y, Yu Y. Tau and neuroinflammation in Alzheimer's disease: interplay mechanisms and clinical translation. J Neuroinflammation 2023; 20:165. [PMID: 37452321 PMCID: PMC10349496 DOI: 10.1186/s12974-023-02853-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 07/12/2023] [Indexed: 07/18/2023] Open
Abstract
Alzheimer's Disease (AD) contributes to most cases of dementia. Its prominent neuropathological features are the extracellular neuritic plaques and intercellular neurofibrillary tangles composed of aggregated β-amyloid (Aβ) and hyperphosphorylated tau protein, respectively. In the past few decades, disease-modifying therapy targeting Aβ has been the focus of AD drug development. Even though it is encouraging that two of these drugs have recently received accelerated US Food and Drug Administration approval for AD treatment, their efficacy or long-term safety is controversial. Tau has received increasing attention as a potential therapeutic target, since evidence indicates that tau pathology is more associated with cognitive dysfunction. Moreover, inflammation, especially neuroinflammation, accompanies AD pathological processes and is also linked to cognitive deficits. Accumulating evidence indicates that inflammation has a complex and tight interplay with tau pathology. Here, we review recent evidence on the interaction between tau pathology, focusing on tau post-translational modification and dissemination, and neuroinflammatory responses, including glial cell activation and inflammatory signaling pathways. Then, we summarize the latest clinical trials targeting tau and neuroinflammation. Sustained and increased inflammatory responses in glial cells and neurons are pivotal cellular drivers and regulators of the exacerbation of tau pathology, which further contributes to its worsening by aggravating inflammatory responses. Unraveling the precise mechanisms underlying the relationship between tau pathology and neuroinflammation will provide new insights into the discovery and clinical translation of therapeutic targets for AD and other tau-related diseases (tauopathies). Targeting multiple pathologies and precision therapy strategies will be the crucial direction for developing drugs for AD and other tauopathies.
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Affiliation(s)
- Yijun Chen
- Shanghai Frontiers Science Center of Drug Target Identification and Delivery, Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yang Yu
- Shanghai Frontiers Science Center of Drug Target Identification and Delivery, Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
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Pardridge WM. Receptor-mediated drug delivery of bispecific therapeutic antibodies through the blood-brain barrier. FRONTIERS IN DRUG DELIVERY 2023; 3:1227816. [PMID: 37583474 PMCID: PMC10426772 DOI: 10.3389/fddev.2023.1227816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
Therapeutic antibody drug development is a rapidly growing sector of the pharmaceutical industry. However, antibody drug development for the brain is a technical challenge, and therapeutic antibodies for the central nervous system account for ~3% of all such agents. The principal obstacle to antibody drug development for brain or spinal cord is the lack of transport of large molecule biologics across the blood-brain barrier (BBB). Therapeutic antibodies can be made transportable through the blood-brain barrier by the re-engineering of the therapeutic antibody as a BBB-penetrating bispecific antibody (BSA). One arm of the BSA is the therapeutic antibody and the other arm of the BSA is a transporting antibody. The transporting antibody targets an exofacial epitope on a BBB receptor, and this enables receptor-mediated transcytosis (RMT) of the BSA across the BBB. Following BBB transport, the therapeutic antibody then engages the target receptor in brain. RMT systems at the BBB that are potential conduits to the brain include the insulin receptor (IR), the transferrin receptor (TfR), the insulin-like growth factor receptor (IGFR) and the leptin receptor. Therapeutic antibodies have been re-engineered as BSAs that target the insulin receptor, TfR, or IGFR RMT systems at the BBB for the treatment of Alzheimer's disease and Parkinson's disease.
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Pinzi L, Bisi N, Sorbi C, Franchini S, Tonali N, Rastelli G. Insights into the Structural Conformations of the Tau Protein in Different Aggregation Status. Molecules 2023; 28:molecules28114544. [PMID: 37299020 DOI: 10.3390/molecules28114544] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/23/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
Tau is a protein characterized by large structural portions displaying extended conformational changes. Unfortunately, the accumulation of this protein into toxic aggregates in neuronal cells leads to a number of severe pathologies, collectively named tauopathies. In the last decade, significant research advancements were achieved, including a better understanding of Tau structures and their implication in different tauopathies. Interestingly, Tau is characterized by a high structural variability depending on the type of disease, the crystallization conditions, and the formation of pathologic aggregates obtained from in vitro versus ex vivo samples. In this review, we reported an up-to-date and comprehensive overview of Tau structures reported in the Protein Data Bank, with a special focus on discussing the connections between structural features, different tauopathies, different crystallization conditions, and the use of in vitro or ex vivo samples. The information reported in this article highlights very interesting links between all these aspects, which we believe may be of particular relevance for a more informed structure-based design of compounds able to modulate Tau aggregation.
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Affiliation(s)
- Luca Pinzi
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Giuseppe Campi 103, 41125 Modena, Italy
| | - Nicolò Bisi
- Centre National de la Recherche Scientifique (CNRS), Université de Paris-Saclay, BioCIS, Bat. Henri Moissan, 17 Av. des Sciences, 91400 Orsay, France
| | - Claudia Sorbi
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Giuseppe Campi 103, 41125 Modena, Italy
| | - Silvia Franchini
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Giuseppe Campi 103, 41125 Modena, Italy
| | - Nicolò Tonali
- Centre National de la Recherche Scientifique (CNRS), Université de Paris-Saclay, BioCIS, Bat. Henri Moissan, 17 Av. des Sciences, 91400 Orsay, France
| | - Giulio Rastelli
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Giuseppe Campi 103, 41125 Modena, Italy
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Karimi N, Bayram Çatak F, Arslan E, Saghazadeh A, Rezaei N. Tau immunotherapy in Alzheimer’s disease and progressive supranuclear palsy. Int Immunopharmacol 2022; 113:109445. [DOI: 10.1016/j.intimp.2022.109445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 11/06/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022]
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Bespalov A, Courade JP, Khiroug L, Terstappen GC, Wang Y. A call for better understanding of target engagement in Tau antibody development. Drug Discov Today 2022; 27:103338. [PMID: 35973661 DOI: 10.1016/j.drudis.2022.103338] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 07/08/2022] [Accepted: 08/11/2022] [Indexed: 11/21/2022]
Abstract
Significant efforts have been channeled into developing antibodies for the treatment of CNS indications. Disappointment with the first generation of clinical Tau antibodies in Alzheimer's disease has highlighted the challenges in understanding whether an antibody can reach or affect the target in the compartment where it is involved in pathological processes. Here, we highlight different aspects essential for improving translatability of Tau-based immunotherapy.
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Affiliation(s)
| | | | | | | | - Yipeng Wang
- Shanghai Qiangrui Biotech, Shanghai, PR China
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Morató X, Pytel V, Jofresa S, Ruiz A, Boada M. Symptomatic and Disease-Modifying Therapy Pipeline for Alzheimer’s Disease: Towards a Personalized Polypharmacology Patient-Centered Approach. Int J Mol Sci 2022; 23:ijms23169305. [PMID: 36012569 PMCID: PMC9409252 DOI: 10.3390/ijms23169305] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 02/07/2023] Open
Abstract
Since 1906, when Dr. Alois Alzheimer first described in a patient “a peculiar severe disease process of the cerebral cortex”, people suffering from this pathology have been waiting for a breakthrough therapy. Alzheimer’s disease (AD) is an irreversible, progressive neurodegenerative brain disorder and the most common form of dementia in the elderly with a long presymptomatic phase. Worldwide, approximately 50 million people are living with dementia, with AD comprising 60–70% of cases. Pathologically, AD is characterized by the deposition of amyloid β-peptide (Aβ) in the neuropil (neuritic plaques) and blood vessels (amyloid angiopathy), and by the accumulation of hyperphosphorylated tau in neurons (neurofibrillary tangles) in the brain, with associated loss of synapses and neurons, together with glial activation, and neuroinflammation, resulting in cognitive deficits and eventually dementia. The current competitive landscape in AD consists of symptomatic treatments, of which there are currently six approved medications: three AChEIs (donepezil, rivastigmine, and galantamine), one NMDA-R antagonist (memantine), one combination therapy (memantine/donepezil), and GV-971 (sodium oligomannate, a mixture of oligosaccharides derived from algae) only approved in China. Improvements to the approved therapies, such as easier routes of administration and reduced dosing frequencies, along with the developments of new strategies and combined treatments are expected to occur within the next decade and will positively impact the way the disease is managed. Recently, Aducanumab, the first disease-modifying therapy (DMT) has been approved for AD, and several DMTs are in advanced stages of clinical development or regulatory review. Small molecules, mAbs, or multimodal strategies showing promise in animal studies have not confirmed that promise in the clinic (where small to moderate changes in clinical efficacy have been observed), and therefore, there is a significant unmet need for a better understanding of the AD pathogenesis and the exploration of alternative etiologies and therapeutic effective disease-modifying therapies strategies for AD. Therefore, a critical review of the disease-modifying therapy pipeline for Alzheimer’s disease is needed.
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Affiliation(s)
- Xavier Morató
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
- Correspondence:
| | - Vanesa Pytel
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
| | - Sara Jofresa
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
| | - Agustín Ruiz
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Mercè Boada
- Research Center and Memory Clinic, Fundació ACE, Institut Català de Neurociències Aplicades, Universitat Internacional de Catalunya, 08017 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, 28029 Madrid, Spain
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14
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La Barbera L, Mauri E, D’Amelio M, Gori M. Functionalization strategies of polymeric nanoparticles for drug delivery in Alzheimer’s disease: Current trends and future perspectives. Front Neurosci 2022; 16:939855. [PMID: 35992936 PMCID: PMC9387393 DOI: 10.3389/fnins.2022.939855] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/11/2022] [Indexed: 12/12/2022] Open
Abstract
Alzheimer’s disease (AD), the most common form of dementia, is a progressive and multifactorial neurodegenerative disorder whose primary causes are mostly unknown. Due to the increase in life expectancy of world population, including developing countries, AD, whose incidence rises dramatically with age, is at the forefront among neurodegenerative diseases. Moreover, a definitive cure is not yet within reach, imposing substantial medical and public health burdens at every latitude. Therefore, the effort to devise novel and effective therapeutic strategies is still of paramount importance. Genetic, functional, structural and biochemical studies all indicate that new and efficacious drug delivery strategies interfere at different levels with various cellular and molecular targets. Over the last few decades, therapeutic development of nanomedicine at preclinical stage has shown to progress at a fast pace, thus paving the way for its potential impact on human health in improving prevention, diagnosis, and treatment of age-related neurodegenerative disorders, including AD. Clinical translation of nano-based therapeutics, despite current limitations, may present important advantages and innovation to be exploited in the neuroscience field as well. In this state-of-the-art review article, we present the most promising applications of polymeric nanoparticle-mediated drug delivery for bypassing the blood-brain barrier of AD preclinical models and boost pharmacological safety and efficacy. In particular, novel strategic chemical functionalization of polymeric nanocarriers that could be successfully employed for treating AD are thoroughly described. Emphasis is also placed on nanotheranostics as both potential therapeutic and diagnostic tool for targeted treatments. Our review highlights the emerging role of nanomedicine in the management of AD, providing the readers with an overview of the nanostrategies currently available to develop future therapeutic applications against this chronic neurodegenerative disease.
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Affiliation(s)
- Livia La Barbera
- Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Rome, Italy
- Santa Lucia Foundation, IRCSS, Rome, Italy
| | - Emanuele Mauri
- Department of Engineering, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Marcello D’Amelio
- Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Rome, Italy
- Santa Lucia Foundation, IRCSS, Rome, Italy
| | - Manuele Gori
- Department of Medicine and Surgery, Università Campus Bio-Medico di Roma, Rome, Italy
- Institute of Biochemistry and Cell Biology (IBBC) - National Research Council (CNR), Rome, Italy
- *Correspondence: Manuele Gori,
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15
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Yokoyama M, Kobayashi H, Tatsumi L, Tomita T. Mouse Models of Alzheimer’s Disease. Front Mol Neurosci 2022; 15:912995. [PMID: 35799899 PMCID: PMC9254908 DOI: 10.3389/fnmol.2022.912995] [Citation(s) in RCA: 66] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 05/23/2022] [Indexed: 11/25/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by memory loss and personality changes, eventually leading to dementia. The pathological hallmarks of AD are senile plaques and neurofibrillary tangles, which comprise abnormally aggregated β-amyloid peptide (Aβ) and hyperphosphorylated tau protein. To develop preventive, diagnostic, and therapeutic strategies for AD, it is essential to establish animal models that recapitulate the pathophysiological process of AD. In this review, we will summarize the advantages and limitations of various mouse models of AD, including transgenic, knock-in, and injection models based on Aβ and tau. We will also discuss other mouse models based on neuroinflammation because recent genetic studies have suggested that microglia are crucial in the pathogenesis of AD. Although each mouse model has its advantages and disadvantages, further research on AD pathobiology will lead to the establishment of more accurate mouse models, and accelerate the development of innovative therapeutics.
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Affiliation(s)
| | | | | | - Taisuke Tomita
- *Correspondence: Taisuke Tomita orcid.org/0000-0002-0075-5943
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16
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Targeted protein degraders march towards the clinic for neurodegenerative diseases. Ageing Res Rev 2022; 78:101616. [PMID: 35378298 DOI: 10.1016/j.arr.2022.101616] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 02/26/2022] [Accepted: 03/30/2022] [Indexed: 12/28/2022]
Abstract
Protein degraders are emerging as potent therapeutic tools to address neurological disorders and many complex diseases. It offered several key advantages, including the doses, drug resistance, and side effects over traditional occupancy-based inhibitors. Translation of chemical degraders into a clinical therapy for neurodegenerative disorders has a well-documented knowledge and resource gap. Researchers strive to develop clinical candidates employing chemical degraders' technologies, including hydrophobic tagging, molecular glues, proteolysis targeting chimeras (PROTACs), specific and nongenetic Inhibitor of Apoptosis Protein (IAP)-dependent protein erasers (SNIPERs), autophagy targeted chimeras, and autophagosome-tethered compounds for targeted degradation of pathological markers in neurodegenerative disease. Herein, we examined the present state of chemical-mediated targeted protein degradation in the quest for medications to treat neurodegenerative diseases. We further identified targeted degraders under clinical development for neurodegenerative diseases summarizing pertinent discoveries guiding the future of degradation therapeutics. We also addressed the necessary pharmacological interventions needed to achieve unprecedented therapeutic efficacy and its associated challenges.
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17
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Lopez-Cuina M, Meissner WG. Targeting alpha-synuclein or tau for treating neurodegenerative movement disorders. Rev Neurol (Paris) 2022; 178:460-471. [PMID: 35562199 DOI: 10.1016/j.neurol.2022.03.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/18/2022] [Accepted: 03/23/2022] [Indexed: 12/31/2022]
Abstract
The two commonest groups of neurodegenerative disorders causing movement disorders are synucleinopathies and tauopathies. These disorders are characterised by the accumulation of abnormally misfolded forms of α-synuclein and tau proteins. Our current understanding of their pathogenesis suggests that extracellular forms of these proteins are of major relevance to the mechanism of pathology propagation throughout the brain and disease progression. The most novel approaches to find disease-modifying therapies aim to reduce or block these forms of tau and α-synuclein. This article reviews therapeutic strategies targeting α-synuclein and tau protein which have entered clinical development.
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Affiliation(s)
- M Lopez-Cuina
- Department of Neurology, Hospital Universitario Reina Sofía, 14004 Cordoba, Spain; University Bordeaux, CNRS, IMN, UMR 5293, 33000 Bordeaux, France
| | - W G Meissner
- University Bordeaux, CNRS, IMN, UMR 5293, 33000 Bordeaux, France; CHU Bordeaux, Service de Neurologie des Maladies Neurodégénératives, IMNc, 33000 Bordeaux, France; Department of Medicine, University of Otago, Christchurch, and New Zealand Brain Research Institute, Christchurch, New Zealand.
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18
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Han ZZ, Kang SG, Arce L, Westaway D. Prion-like strain effects in tauopathies. Cell Tissue Res 2022; 392:179-199. [PMID: 35460367 PMCID: PMC9034081 DOI: 10.1007/s00441-022-03620-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 03/25/2022] [Indexed: 12/30/2022]
Abstract
Tau is a microtubule-associated protein that plays crucial roles in physiology and pathophysiology. In the realm of dementia, tau protein misfolding is associated with a wide spectrum of clinicopathologically diverse neurodegenerative diseases, collectively known as tauopathies. As proposed by the tau strain hypothesis, the intrinsic heterogeneity of tauopathies may be explained by the existence of structurally distinct tau conformers, “strains”. Tau strains can differ in their associated clinical features, neuropathological profiles, and biochemical signatures. Although prior research into infectious prion proteins offers valuable lessons for studying how a protein-only pathogen can encompass strain diversity, the underlying mechanism by which tau subtypes are generated remains poorly understood. Here we summarize recent advances in understanding different tau conformers through in vivo and in vitro experimental paradigms, and the implications of heterogeneity of pathological tau species for drug development.
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Affiliation(s)
- Zhuang Zhuang Han
- Centre for Prions and Protein Folding Diseases, University of Alberta, 204 Brain and Aging Research Building, Edmonton, AB, T6G 2M8, Canada.,Department of Medicine, University of Alberta, Edmonton, AB, Canada.,Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - Sang-Gyun Kang
- Centre for Prions and Protein Folding Diseases, University of Alberta, 204 Brain and Aging Research Building, Edmonton, AB, T6G 2M8, Canada.,Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Luis Arce
- Centre for Prions and Protein Folding Diseases, University of Alberta, 204 Brain and Aging Research Building, Edmonton, AB, T6G 2M8, Canada.,Department of Medicine, University of Alberta, Edmonton, AB, Canada.,Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - David Westaway
- Centre for Prions and Protein Folding Diseases, University of Alberta, 204 Brain and Aging Research Building, Edmonton, AB, T6G 2M8, Canada. .,Department of Medicine, University of Alberta, Edmonton, AB, Canada. .,Department of Biochemistry, University of Alberta, Edmonton, AB, Canada.
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19
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Langer A, Lüdecke A, Bartoschik T, Cehlar O, Duhr S, Baaske P, Streicher W. A New Spectral Shift-Based Method to Characterize Molecular Interactions. Assay Drug Dev Technol 2022; 20:83-94. [PMID: 35171002 PMCID: PMC8968852 DOI: 10.1089/adt.2021.133] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
There are many fluorescence-based applications that can be used to characterize molecular interactions. However, available methods often depend on site-specific labeling techniques or binding-induced changes in conformation or size of the probed target molecule. To overcome these limitations, we applied a ratiometric dual-emission approach that quantifies ligand-induced spectral shifts with sub-nanometer sensitivity. The use of environment-sensitive near-infrared dyes with the method we describe enables affinity measurements and thermodynamic characterization without the explicit need for site-specific labeling or ligand-induced conformational changes. We demonstrate that in-solution spectral shift measurements enable precise characterization of molecular interactions for a variety of biomolecules, including proteins, antibodies, and nucleic acids. Thereby, the described method is not limited to a subset of molecules since even the most challenging samples of research and drug discovery projects like membrane proteins and intrinsically disordered proteins can be analyzed.
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Affiliation(s)
| | | | | | - Ondrej Cehlar
- Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Stefan Duhr
- NanoTemper Technologies GmbH, Munich, Germany
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20
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Non-invasive imaging of tau-targeted probe uptake by whole brain multi-spectral optoacoustic tomography. Eur J Nucl Med Mol Imaging 2022; 49:2137-2152. [PMID: 35128565 PMCID: PMC9165274 DOI: 10.1007/s00259-022-05708-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 01/25/2022] [Indexed: 02/06/2023]
Abstract
Purpose Abnormal tau accumulation within the brain plays an important role in tauopathies such as Alzheimer’s disease and frontotemporal dementia. High-resolution imaging of tau deposits at the whole-brain scale in animal disease models is highly desired. Methods We approached this challenge by non-invasively imaging the brains of P301L mice of 4-repeat tau with concurrent volumetric multi-spectral optoacoustic tomography (vMSOT) at ~ 115 μm spatial resolution using the tau-targeted pyridinyl-butadienyl-benzothiazole derivative PBB5 (i.v.). In vitro probe characterization, concurrent vMSOT and epi-fluorescence imaging of in vivo PBB5 targeting (i.v.) was performed in P301L and wild-type mice, followed by ex vivo validation using AT-8 antibody for phosphorylated tau. Results PBB5 showed specific binding to recombinant K18 tau fibrils by fluorescence assay, to post-mortem Alzheimer’s disease brain tissue homogenate by competitive binding against [11C]PBB3 and to tau deposits (AT-8 positive) in post-mortem corticobasal degeneration and progressive supranuclear palsy brains. Dose-dependent optoacoustic and fluorescence signal intensities were observed in the mouse brains following i.v. administration of different concentrations of PBB5. In vivo vMSOT brain imaging of P301L mice showed higher retention of PBB5 in the tau-laden cortex and hippocampus compared to wild-type mice, as confirmed by ex vivo vMSOT, epi-fluorescence, multiphoton microscopy, and immunofluorescence staining. Conclusions We demonstrated non-invasive whole-brain imaging of tau in P301L mice with vMSOT system using PBB5 at a previously unachieved ~ 115 μm spatial resolution. This platform provides a new tool to study tau spreading and clearance in a tauopathy mouse model, foreseeable in monitoring tau targeting putative therapeutics. Supplementary Information The online version contains supplementary material available at 10.1007/s00259-022-05708-w.
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21
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Golde TE. Disease-Modifying Therapies for Alzheimer's Disease: More Questions than Answers. Neurotherapeutics 2022; 19:209-227. [PMID: 35229269 PMCID: PMC8885119 DOI: 10.1007/s13311-022-01201-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/09/2022] [Indexed: 12/17/2022] Open
Abstract
Scientific advances over the last four decades have steadily infused the Alzheimer's disease (AD) field with great optimism that therapies targeting Aβ, amyloid, tau, and innate immune activation states in the brain would provide disease modification. Unfortunately, this optimistic scenario has not yet played out. Though a recent approval of the anti-Aβ aggregate binding antibody, Aduhelm (aducanumab), as a "disease-modifying therapy for AD" is viewed by some as a breakthrough, many remain unconvinced by the data underlying this approval. Collectively, we have not succeeded in changing AD from a largely untreatable, inevitable, and incurable disease to a treatable, preventable, and curable one. Here, I will review the major foci of the AD "disease-modifying" therapeutic pipeline and some of the "open questions" that remain in terms of these therapeutic approaches. I will conclude the review by discussing how we, as a field, might adjust our approach, learning from our past failures to ensure future success.
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Affiliation(s)
- Todd E Golde
- Departments of Neuroscience and Neurology, Center for Translational Research in Neurodegenerative Disease, Evelyn F. and William L. McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, USA.
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22
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Giovannini J, Smeralda W, Jouanne M, Sopkova-de Oliveira Santos J, Catto M, Sophie Voisin-Chiret A. Tau protein aggregation: key features to improve drug discovery screening. Drug Discov Today 2022; 27:1284-1297. [DOI: 10.1016/j.drudis.2022.01.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/29/2021] [Accepted: 01/20/2022] [Indexed: 12/17/2022]
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23
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Congdon EE, Jiang Y, Sigurdsson EM. Targeting tau only extracellularly is likely to be less efficacious than targeting it both intra- and extracellularly. Semin Cell Dev Biol 2021; 126:125-137. [PMID: 34896021 DOI: 10.1016/j.semcdb.2021.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 12/11/2022]
Abstract
Aggregation of the tau protein is thought to be responsible for the neurodegeneration and subsequent functional impairments in diseases that are collectively named tauopathies. Alzheimer's disease is the most common tauopathy, but the group consists of over 20 different diseases, many of which have tau pathology as their primary feature. The development of tau therapies has mainly focused on preventing the formation of and/or clearing these aggregates. Of these, immunotherapies that aim to either elicit endogenous tau antibodies or deliver exogenous ones are the most common approach in clinical trials. While their mechanism of action can involve several pathways, both extra- and intracellular, pharmaceutical companies have primarily focused on antibody-mediated clearance of extracellular tau. As we have pointed out over the years, this is rather surprising because it is well known that most of pathological tau protein is found intracellularly. It has been repeatedly shown by several groups over the past decades that antibodies can enter neurons and that their cellular uptake can be enhanced by various means, particularly by altering their charge. Here, we will briefly describe the potential extra- and intracellular mechanisms involved in antibody-mediated clearance of tau pathology, discuss these in the context of recent failures of some of the tau antibody trials, and finally provide a brief overview of how the intracellular efficacy of tau antibodies can potentially be further improved by certain modifications that aim to enhance tau clearance via specific intracellular degradation pathways.
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Affiliation(s)
- Erin E Congdon
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States.
| | - Yixiang Jiang
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States; Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, United States.
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24
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Imbimbo BP, Ippati S, Watling M, Balducci C. A critical appraisal of tau-targeting therapies for primary and secondary tauopathies. Alzheimers Dement 2021; 18:1008-1037. [PMID: 34533272 DOI: 10.1002/alz.12453] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/20/2021] [Accepted: 07/26/2021] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Primary tauopathies are neurological disorders in which tau protein deposition is the predominant pathological feature. Alzheimer's disease is a secondary tauopathy with tau forming hyperphosphorylated insoluble aggregates. Tau pathology can propagate from region to region in the brain, while alterations in tau processing may impair tau physiological functions. METHODS We reviewed literature on tau biology and anti-tau drugs using PubMed, meeting abstracts, and ClnicalTrials.gov. RESULTS The past 15 years have seen >30 drugs interfering with tau aggregation, processing, and accumulation reaching the clinic. Initial results with tau aggregation inhibitors and anti-tau monoclonal antibodies have not shown clinical efficacy. DISCUSSION The reasons for these clinical failures are unclear but could be linked to the clearing of physiological forms of tau by non-specific drugs. Research is now concentrating efforts on developing reliable translational animal models and selective compounds targeting specific tau epitopes, neurotoxic tau aggregates, and post-translational tau modifications.
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Affiliation(s)
- Bruno P Imbimbo
- Department of Research & Development, Chiesi Farmaceutici, Parma, Italy
| | - Stefania Ippati
- San Raffaele Scientific Institute, San Raffaele Hospital, Milan, Italy
| | - Mark Watling
- CNS & Pain Department, TranScrip Ltd, Reading, UK
| | - Claudia Balducci
- Department of Neuroscience, Istituto di Ricerche Farmacologiche "Mario Negri" IRCCS, Milan, Italy
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25
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Fields E, Vaughan E, Tripu D, Lim I, Shrout K, Conway J, Salib N, Lee Y, Dhamsania A, Jacobsen M, Woo A, Xue H, Cao K. Gene targeting techniques for Huntington's disease. Ageing Res Rev 2021; 70:101385. [PMID: 34098113 PMCID: PMC8373677 DOI: 10.1016/j.arr.2021.101385] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 05/24/2021] [Accepted: 06/03/2021] [Indexed: 02/08/2023]
Abstract
Huntington's disease (HD) is an autosomal neurodegenerative disorder caused by extended trinucleotide CAG repetition in the HTT gene. Wild-type huntingtin protein (HTT) is essential, involved in a variety of crucial cellular functions such as vesicle transportation, cell division, transcription regulation, autophagy, and tissue maintenance. The mutant HTT (mHTT) proteins in the body interfere with HTT's normal cellular functions and cause additional detrimental effects. In this review, we discuss multiple approaches targeting DNA and RNA to reduce mHTT expression. These approaches are categorized into non-allele-specific silencing and allele-specific-silencing using Single Nucleotide Polymorphisms (SNPs) and haplogroup analysis. Additionally, this review discusses a potential application of recent CRISPR prime editing technology in targeting HD.
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Affiliation(s)
- Eric Fields
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Erik Vaughan
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Deepika Tripu
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Isabelle Lim
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Katherine Shrout
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Jessica Conway
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Nicole Salib
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Yubin Lee
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Akash Dhamsania
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Michael Jacobsen
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Ashley Woo
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States
| | - Huijing Xue
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, United States
| | - Kan Cao
- Gemstone Honors Program, University of Maryland, College Park, MD 20742, United States; Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, United States.
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26
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Jabbari E, Duff KE. Tau-targeting antibody therapies: too late, wrong epitope or wrong target? Nat Med 2021; 27:1341-1342. [PMID: 34385709 DOI: 10.1038/s41591-021-01465-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Edwin Jabbari
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK. .,Movement Disorders Centre, UCL Queen Square Institute of Neurology, London, UK.
| | - Karen E Duff
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA. .,UK Dementia Research Institute, University College London, London, UK.
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27
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Safety and efficacy of anti-tau monoclonal antibody gosuranemab in progressive supranuclear palsy: a phase 2, randomized, placebo-controlled trial. Nat Med 2021; 27:1451-1457. [PMID: 34385707 DOI: 10.1038/s41591-021-01455-x] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 06/28/2021] [Indexed: 02/07/2023]
Abstract
A randomized, double-blind, placebo-controlled, 52-week study (no. NCT03068468) evaluated gosuranemab, an anti-tau monoclonal antibody, in the treatment of progressive supranuclear palsy (PSP). In total, 486 participants dosed were assigned to either gosuranemab (n = 321) or placebo (n = 165). Efficacy was not demonstrated on adjusted mean change of PSP Rating Scale score at week 52 between gosuranemab and placebo (10.4 versus 10.6, P = 0.85, primary endpoint), or at secondary endpoints, resulting in discontinuation of the open-label, long-term extension. Unbound N-terminal tau in cerebrospinal fluid decreased by 98% with gosuranemab and increased by 11% with placebo (P < 0.0001). Incidences of adverse events and deaths were similar between groups. This well-powered study suggests that N-terminal tau neutralization does not translate into clinical efficacy.
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Kim B, Mikytuck B, Suh E, Gibbons GS, Van Deerlin VM, Vaishnavi SN, Spindler MA, Massimo L, Grossman M, Trojanowski JQ, Irwin DJ, Lee EB. Tau immunotherapy is associated with glial responses in FTLD-tau. Acta Neuropathol 2021; 142:243-257. [PMID: 33950293 PMCID: PMC8270872 DOI: 10.1007/s00401-021-02318-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 12/22/2022]
Abstract
Progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are neuropathologic subtypes of frontotemporal lobar degeneration with tau inclusions (FTLD-tau), primary tauopathies in which intracellular tau aggregation contributes to neurodegeneration. Gosuranemab (BIIB092) is a humanized monoclonal antibody that binds to N-terminal tau. While Gosuranemab passive immunotherapy trials for PSP failed to demonstrate clinical benefit, Gosuranemab reduced N-terminal tau in the cerebrospinal fluid of transgenic mouse models and PSP patients. However, the neuropathologic sequelae of Gosuranemab have not been described. In this present study, we examined the brain tissue of three individuals who received Gosuranemab. Post-mortem human brain tissues were studied using immunohistochemistry to identify astrocytic and microglial differences between immunized cases and a cohort of unimmunized PSP, CBD and aging controls. Gosuranemab immunotherapy was not associated with clearance of neuropathologic FTLD-tau inclusions. However, treatment-associated changes were observed including the presence of perivascular vesicular astrocytes (PVA) with tau accumulation within lysosomes. PVAs were morphologically and immunophenotypically distinct from the tufted astrocytes seen in PSP, granular fuzzy astrocytes (GFA) seen in aging, and astrocytic plaques seen in CBD. Additional glial responses included increased reactive gliosis consisting of bushy astrocytosis and accumulation of rod microglia. Together, these neuropathologic findings suggest that Gosuranemab may be associated with a glial response including accumulation of tau within astrocytic lysosomes.
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Affiliation(s)
- Boram Kim
- Translational Neuropathology Research Laboratory, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, 613A Stellar Chance Laboratories, 422 Curie Blvd, Philadelphia, PA, 19104, USA
| | - Bailey Mikytuck
- Translational Neuropathology Research Laboratory, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, 613A Stellar Chance Laboratories, 422 Curie Blvd, Philadelphia, PA, 19104, USA
| | - Eunran Suh
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Garrett S Gibbons
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Vivianna M Van Deerlin
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Sanjeev N Vaishnavi
- Penn Memory Center, Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Meredith A Spindler
- Parkinson's Disease and Movement Disorders Center, Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Lauren Massimo
- Penn Frontotemporal Degeneration Center, Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Murray Grossman
- Penn Frontotemporal Degeneration Center, Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - John Q Trojanowski
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - David J Irwin
- Penn Frontotemporal Degeneration Center, Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Edward B Lee
- Translational Neuropathology Research Laboratory, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, 613A Stellar Chance Laboratories, 422 Curie Blvd, Philadelphia, PA, 19104, USA.
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Ji C, Sigurdsson EM. Current Status of Clinical Trials on Tau Immunotherapies. Drugs 2021; 81:1135-1152. [PMID: 34101156 DOI: 10.1007/s40265-021-01546-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/22/2021] [Indexed: 12/12/2022]
Abstract
Tau immunotherapies have advanced from proof-of-concept studies to over a dozen clinical trials for Alzheimer's disease (AD) and other tauopathies. Mechanistic studies in animal and culture models have provided valuable insight into how these therapies may work but multiple pathways are likely involved. Different groups have emphasized the importance of intracellular vs extracellular antibody-mediated clearance of the tau protein and there is no consensus on which pool of tau should ideally be targeted. Likewise, various normal and disease-selective epitopes are being targeted, and the antibody isotypes either favor phagocytosis of the tau-antibody complex or are neutral in that aspect. Most of the clinical trials are in early stages, thus their efficacy is not yet known, but all have been without any major adverse effects and some have reported target engagement. A few have been discontinued. One in phase I, presumably because of a poor pharmacokinetic profile, and three in phase II for a lack of efficacy although this trial stage is not well powered for efficacy measures. In these phase II studies, trials with two antibodies in patients with progressive supranuclear palsy or other primary tauopathies were halted but are continuing in patients with AD, and one antibody trial was stopped in early-stage AD but is continuing in moderate AD. These three antibodies have been reported to only work extracellularly and tau is not increased in the cerebrospinal fluid of primary tauopathies, which may explain the failures of two of them. In the discontinued AD trial, there are some concerns about how much of extracellular tau contains the N-terminal epitope that is being targeted. In addition, extracellular tau is only a small part of total tau, compared to intracellular tau. Targeting only the former may not be sufficient for functional benefits. Given these outcomes, decision makers within the pharmaceutical companies who green light these trials should attempt to target tau not only extracellularly but also intracellularly to increase their chances of success. Hopefully, some of the ongoing trials will provide some functional benefits to the large number of patients with tauopathies.
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Affiliation(s)
- Changyi Ji
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, Science Building, 11th floor, 435 East 30th Street, New York, NY, 10016, USA
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, Science Building, 11th floor, 435 East 30th Street, New York, NY, 10016, USA. .,Department of Psychiatry, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY, USA.
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Feasibility of short imaging protocols for [ 18F]PI-2620 tau-PET in progressive supranuclear palsy. Eur J Nucl Med Mol Imaging 2021; 48:3872-3885. [PMID: 34021393 PMCID: PMC8484138 DOI: 10.1007/s00259-021-05391-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 04/26/2021] [Indexed: 11/08/2022]
Abstract
Purpose Dynamic 60-min positron emission tomography (PET) imaging with the novel tau radiotracer [18F]PI-2620 facilitated accurate discrimination between patients with progressive supranuclear palsy (PSP) and healthy controls (HCs). This study investigated if truncated acquisition and static time windows can be used for [18F]PI-2620 tau-PET imaging of PSP. Methods Thirty-seven patients with PSP Richardson syndrome (PSP-RS) were evaluated together with ten HCs. [18F]PI-2620 PET was performed by a dynamic 60-min scan. Distribution volume ratios (DVRs) were calculated using full and truncated scan durations (0–60, 0–50, 0–40, 0–30, and 0–20 min p.i.). Standardized uptake value ratios (SUVrs) were obtained 20–40, 30–50, and 40–60 min p.i.. All DVR and SUVr data were compared with regard to their potential to discriminate patients with PSP-RS from HCs in predefined subcortical and cortical target regions (effect size, area under the curve (AUC), multi-region classifier). Results 0–50 and 0–40 DVR showed equivalent effect sizes as 0–60 DVR (averaged Cohen’s d: 1.22 and 1.16 vs. 1.26), whereas the performance dropped for 0–30 or 0–20 DVR. The 20–40 SUVr indicated the best performance of all static acquisition windows (averaged Cohen’s d: 0.99). The globus pallidus internus discriminated patients with PSP-RS and HCs at a similarly high level for 0–60 DVR (AUC: 0.96), 0–40 DVR (AUC: 0.96), and 20–40 SUVr (AUC: 0.94). The multi-region classifier sensitivity of these time windows was consistently 86%. Conclusion Truncated and static imaging windows can be used for [18F]PI-2620 PET imaging of PSP. 0–40 min dynamic scanning offers the best balance between accuracy and economic scanning. Supplementary Information The online version contains supplementary material available at 10.1007/s00259-021-05391-3.
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Silva MC, Haggarty SJ. Tauopathies: Deciphering Disease Mechanisms to Develop Effective Therapies. Int J Mol Sci 2020; 21:ijms21238948. [PMID: 33255694 PMCID: PMC7728099 DOI: 10.3390/ijms21238948] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/20/2020] [Accepted: 11/22/2020] [Indexed: 12/13/2022] Open
Abstract
Tauopathies are neurodegenerative diseases characterized by the pathological accumulation of microtubule-associated protein tau (MAPT) in the form of neurofibrillary tangles and paired helical filaments in neurons and glia, leading to brain cell death. These diseases include frontotemporal dementia (FTD) and Alzheimer's disease (AD) and can be sporadic or inherited when caused by mutations in the MAPT gene. Despite an incredibly high socio-economic burden worldwide, there are still no effective disease-modifying therapies, and few tau-focused experimental drugs have reached clinical trials. One major hindrance for therapeutic development is the knowledge gap in molecular mechanisms of tau-mediated neuronal toxicity and death. For the promise of precision medicine for brain disorders to be fulfilled, it is necessary to integrate known genetic causes of disease, i.e., MAPT mutations, with an understanding of the dysregulated molecular pathways that constitute potential therapeutic targets. Here, the growing understanding of known and proposed mechanisms of disease etiology will be reviewed, together with promising experimental tau-directed therapeutics, such as recently developed tau degraders. Current challenges faced by the fields of tau research and drug discovery will also be addressed.
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Pardridge WM. Treatment of Alzheimer's Disease and Blood-Brain Barrier Drug Delivery. Pharmaceuticals (Basel) 2020; 13:E394. [PMID: 33207605 PMCID: PMC7697739 DOI: 10.3390/ph13110394] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 12/12/2022] Open
Abstract
Despite the enormity of the societal and health burdens caused by Alzheimer's disease (AD), there have been no FDA approvals for new therapeutics for AD since 2003. This profound lack of progress in treatment of AD is due to dual problems, both related to the blood-brain barrier (BBB). First, 98% of small molecule drugs do not cross the BBB, and ~100% of biologic drugs do not cross the BBB, so BBB drug delivery technology is needed in AD drug development. Second, the pharmaceutical industry has not developed BBB drug delivery technology, which would enable industry to invent new therapeutics for AD that actually penetrate into brain parenchyma from blood. In 2020, less than 1% of all AD drug development projects use a BBB drug delivery technology. The pathogenesis of AD involves chronic neuro-inflammation, the progressive deposition of insoluble amyloid-beta or tau aggregates, and neural degeneration. New drugs that both attack these multiple sites in AD, and that have been coupled with BBB drug delivery technology, can lead to new and effective treatments of this serious disorder.
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Affiliation(s)
- William M Pardridge
- Department of Medicine, University of California, Los Angeles, CA 90024, USA
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