1
|
Bell TM, Facemire P, Bearss JJ, Raymond JL, Chapman J, Zeng X, Shamblin JD, Williams JA, Grosenbach DW, Hruby DE, Damon IK, Goff AJ, Mucker EM. Smallpox lesion characterization in placebo-treated and tecovirimat-treated macaques using traditional and novel methods. PLoS Pathog 2024; 20:e1012007. [PMID: 38386661 PMCID: PMC10883539 DOI: 10.1371/journal.ppat.1012007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 01/26/2024] [Indexed: 02/24/2024] Open
Abstract
Smallpox was the most rampant infectious disease killer of the 20th century, yet much remains unknown about the pathogenesis of the variola virus. Using archived tissue from a study conducted at the Centers for Disease Control and Prevention we characterized pathology in 18 cynomolgus macaques intravenously infected with the Harper strain of variola virus. Six macaques were placebo-treated controls, six were tecovirimat-treated beginning at 2 days post-infection, and six were tecovirimat-treated beginning at 4 days post-infection. All macaques were treated daily until day 17. Archived tissues were interrogated using immunohistochemistry, in situ hybridization, immunofluorescence, and electron microscopy. Gross lesions in three placebo-treated animals that succumbed to infection primarily consisted of cutaneous vesicles, pustules, or crusts with lymphadenopathy. The only gross lesions noted at the conclusion of the study in the three surviving placebo-treated and the Day 4 treated animals consisted of resolving cutaneous pox lesions. No gross lesions attributable to poxviral infection were present in the Day 2 treated macaques. Histologic lesions in three placebo-treated macaques that succumbed to infection consisted of proliferative and necrotizing dermatitis with intracytoplasmic inclusion bodies and lymphoid depletion. The only notable histologic lesion in the Day 4 treated macaques was resolving dermatitis; no notable lesions were seen in the Day 2 treated macaques. Variola virus was detected in all three placebo-treated animals that succumbed to infection prior to the study's conclusion by all utilized methods (IHC, ISH, IFA, EM). None of the three placebo-treated animals that survived to the end of the study nor the animals in the two tecovirimat treatment groups showed evidence of variola virus by these methods. Our findings further characterize variola lesions in the macaque model and describe new molecular methods for variola detection.
Collapse
Affiliation(s)
- Todd M. Bell
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | - Paul Facemire
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | - Jeremy J. Bearss
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | - Jo Lynne Raymond
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | - Jennifer Chapman
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | - Xiankun Zeng
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | - Joshua D. Shamblin
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | - Janice A. Williams
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | | | - Dennis E. Hruby
- SIGA Technologies, Inc., Corvallis, Oregon, United States of America
| | - Inger K. Damon
- Poxvirus and Rabies Branch, Centers for Disease Control and Prevention (CDC) Atlanta, Georgia, United States of America
| | - Arthur J. Goff
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| | - Eric M. Mucker
- U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, Maryland, United States of America
| |
Collapse
|
2
|
Abstract
Human monkeypox is a viral zoonosis endemic to West and Central Africa that has recently generated increased interest and concern on a global scale as an emerging infectious disease threat in the midst of the slowly relenting COVID-2019 disease pandemic. The hallmark of infection is the development of a flu-like prodrome followed by the appearance of a smallpox-like exanthem. Precipitous person-to-person transmission of the virus among residents of 100 countries where it is nonendemic has motivated the immediate and widespread implementation of public health countermeasures. In this review, we discuss the origins and virology of monkeypox virus, its link with smallpox eradication, its record of causing outbreaks of human disease in regions where it is endemic in wildlife, its association with outbreaks in areas where it is nonendemic, the clinical manifestations of disease, laboratory diagnostic methods, case management, public health interventions, and future directions.
Collapse
Affiliation(s)
- Sameer Elsayed
- Department of Medicine, Western University, London, Ontario, Canada
- Department of Pathology & Laboratory Medicine, Western University, London, Ontario, Canada
- Department of Epidemiology & Biostatistics, Western University, London, Ontario, Canada
| | - Lise Bondy
- Department of Medicine, Western University, London, Ontario, Canada
| | - William P. Hanage
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| |
Collapse
|
3
|
Therapeutic strategies for human poxvirus infections: Monkeypox (mpox), smallpox, molluscipox, and orf. Travel Med Infect Dis 2022; 52:102528. [PMID: 36539022 PMCID: PMC9758798 DOI: 10.1016/j.tmaid.2022.102528] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 12/01/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022]
Abstract
Therapeutic and vaccine development for human poxvirus infections (e.g., monkeypox (mpox) virus, variola virus, molluscum contagiosum virus, orf virus) has been largely deserted, especially after the eradication of smallpox by 1980. Human mpox is a self-limited disease confined to Central and West Africa for decades. However, since April 2022, mpox has quickly emerged as a multi-country outbreak, urgently calling for effective antiviral agents and vaccines to control mpox. Here, this review highlights possible therapeutic options (e.g., tecovirimat, brincidofovir, cidofovir) and other strategies (e.g., vaccines, intravenous vaccinia immune globulin) for the management of human poxvirus infections worldwide.
Collapse
|
4
|
Singh S, Kumar R, Singh SK. All That We Need to Know About the Current and Past Outbreaks of Monkeypox: A Narrative Review. Cureus 2022; 14:e31109. [DOI: 10.7759/cureus.31109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2022] [Indexed: 11/07/2022] Open
|
5
|
Abstract
Severe illness caused by coronavirus disease 2019 (COVID-19) is characterized by an overexuberant inflammatory response resulting in acute respiratory distress syndrome (ARDS) and progressive respiratory failure (A. Gupta, M. V. Madhavan, K. Sehgal, N. Nair, et al., Nat Med 26:1017–1032, 2020, https://doi.org/10.1038/s41591-020-0968-3). Rhesus theta (θ) defensin-1 (RTD-1) is a macrocyclic host defense peptide exhibiting antimicrobial and immunomodulatory activities. RTD-1 treatment significantly improved survival in murine models of a severe acute respiratory syndrome (SARS-CoV-1) and endotoxin-induced acute lung injury (ALI) (C. L. Wohlford-Lenane, D. K. Meyerholz, S. Perlman, H. Zhou, et al., J Virol 83:11385–11390, 2009, https://doi.org/10.1128/JVI.01363-09; J. G. Jayne, T. J. Bensman, J. B. Schaal, A. Y. J. Park, et al., Am J Respir Cell Mol Biol 58:310–319, 2018, https://doi.org/10.1165/rcmb.2016-0428OC). This investigation aimed to characterize the preclinical pharmacokinetics (PK) and safety of intravenous (i.v.) RTD-1. Based on the lack of adverse findings, the no observed adverse effect level (NOAEL) was established at 10 mg/kg/day in rats and 15 mg/kg/day in monkeys. Analysis of single ascending dose studies in both species revealed greater-than-dose-proportional increases in the area under the curve extrapolated to infinity (AUC0-∞) (e.g., 8-fold increase from 5 mg/kg to 20 mg/kg in rats) suggestive of nonlinear PK. The volume of distribution at steady state (Vss) ranged between 550 and 1,461 mL/kg, indicating extensive tissue distribution, which was validated in a biodistribution study of [14C]RTD-1 in rats. Based on interspecies allometric scaling, the predicted human clearance and Vss are 6.48 L/h and 28.0 L, respectively, for an adult (70 kg). To achieve plasma exposures associated with therapeutic efficacy established in a murine model of ALI, the estimated human equivalent dose (HED) is between 0.36 and 0.83 mg/kg/day. The excellent safety profile demonstrated in these studies and the efficacy observed in the murine models support the clinical investigation of RTD-1 for treatment of COVID-19 or other pulmonary inflammatory diseases.
Collapse
|
6
|
Hanafin PO, Jermain B, Hickey AJ, Kabanov AV, Kashuba ADM, Sheahan TP, Rao GG. A mechanism-based pharmacokinetic model of remdesivir leveraging interspecies scaling to simulate COVID-19 treatment in humans. CPT Pharmacometrics Syst Pharmacol 2021; 10:89-99. [PMID: 33296558 PMCID: PMC7894405 DOI: 10.1002/psp4.12584] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/18/2020] [Accepted: 11/18/2020] [Indexed: 12/17/2022] Open
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak initiated the global coronavirus disease 2019 (COVID-19) pandemic resulting in 42.9 million confirmed infections and > 1.1 million deaths worldwide as of October 26, 2020. Remdesivir is a broad-spectrum nucleotide prodrug shown to be effective against enzootic coronaviruses. The pharmacokinetics (PKs) of remdesivir in plasma have recently been described. However, the distribution of its active metabolite nucleoside triphosphate (NTP) to the site of pulmonary infection is unknown in humans. Our objective was to use existing in vivo mouse PK data for remdesivir and its metabolites to develop a mechanism-based model to allometrically scale and simulate the human PK of remdesivir in plasma and NTP in lung homogenate. Remdesivir and GS-441524 concentrations in plasma and total phosphorylated nucleoside concentrations in lung homogenate from Ces1c-/- mice administered 25 or 50 mg/kg of remdesivir subcutaneously were simultaneously fit to estimate PK parameters. The mouse PK model was allometrically scaled to predict human PK parameters to simulate the clinically recommended 200 mg loading dose followed by 100 mg daily maintenance doses administered as 30-minute intravenous infusions. Simulations of unbound remdesivir concentrations in human plasma were below 2.48 μM, the 90% maximal inhibitory concentration for SARS-CoV-2 inhibition in vitro. Simulations of NTP in the lungs were below high efficacy in vitro thresholds. We have identified a need for alternative dosing strategies to achieve more efficacious concentrations of NTP in human lungs, perhaps by reformulating remdesivir for direct pulmonary delivery.
Collapse
Affiliation(s)
- Patrick O. Hanafin
- Division of Pharmacotherapy and Experimental TherapeuticsEshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - Brian Jermain
- Division of Pharmacotherapy and Experimental TherapeuticsEshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - Anthony J. Hickey
- Division of Pharmacoengineering and Molecular PharmaceuticsEshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNCUSA
- RTI InternationalResearch Triangle ParkNCUSA
| | - Alexander V. Kabanov
- Division of Pharmacoengineering and Molecular PharmaceuticsEshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - Angela DM. Kashuba
- Division of Pharmacotherapy and Experimental TherapeuticsEshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - Timothy P. Sheahan
- Department of EpidemiologyGillings School of Global Public HealthUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - Gauri G. Rao
- Division of Pharmacotherapy and Experimental TherapeuticsEshelman School of PharmacyUniversity of North Carolina at Chapel HillChapel HillNCUSA
| |
Collapse
|
7
|
Zou H, Banerjee P, Leung SSY, Yan X. Application of Pharmacokinetic-Pharmacodynamic Modeling in Drug Delivery: Development and Challenges. Front Pharmacol 2020; 11:997. [PMID: 32719604 PMCID: PMC7348046 DOI: 10.3389/fphar.2020.00997] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 06/19/2020] [Indexed: 12/19/2022] Open
Abstract
With the advancement of technology, drug delivery systems and molecules with more complex architecture are developed. As a result, the drug absorption and disposition processes after administration of these drug delivery systems and engineered molecules become exceedingly complex. As the pharmacokinetic and pharmacodynamic (PK-PD) modeling allows for the separation of the drug-, carrier- and pharmacological system-specific parameters, it has been widely used to improve understanding of the in vivo behavior of these complex delivery systems and help their development. In this review, we summarized the basic PK-PD modeling theory in drug delivery and demonstrated how it had been applied to help the development of new delivery systems and modified large molecules. The linkage between PK and PD was highlighted. In particular, we exemplified the application of PK-PD modeling in the development of extended-release formulations, liposomal drugs, modified proteins, and antibody-drug conjugates. Furthermore, the model-based simulation using primary PD models for direct and indirect PD responses was conducted to explain the assertion of hypothetical minimal effective concentration or threshold in the exposure-response relationship of many drugs and its misconception. The limitations and challenges of the mechanism-based PK-PD model were also discussed.
Collapse
Affiliation(s)
- Huixi Zou
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| | - Parikshit Banerjee
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| | - Sharon Shui Yee Leung
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| | - Xiaoyu Yan
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| |
Collapse
|
8
|
Merchlinsky M, Albright A, Olson V, Schiltz H, Merkeley T, Hughes C, Petersen B, Challberg M. The development and approval of tecoviromat (TPOXX ®), the first antiviral against smallpox. Antiviral Res 2019; 168:168-174. [PMID: 31181284 DOI: 10.1016/j.antiviral.2019.06.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 06/06/2019] [Indexed: 11/16/2022]
Abstract
The classification of smallpox by the U.S. Centers for Disease Control and Prevention (CDC) as a Category A Bioterrorism threat agent has resulted in the U.S. Government investing significant funds to develop and stockpile a suite of medical countermeasures to ameliorate the consequences of a smallpox epidemic. This stockpile includes both vaccines for prophylaxis and antivirals to treat symptomatic patients. In this manuscript, we describe the path to approval for the first therapeutic against smallpox, identified during its development as ST-246, now known as tecovirimat and TPOXX®, a small-molecule antiviral compound sponsored by SIGA Technologies to treat symptomatic smallpox. Because the disease is no longer endemic, the development and approval of TPOXX® was only possible under the U.S. Food and Drug and Administration Animal Rule (FDA 2002). In this article, we describe the combination of animal model studies and clinical trials that were used to satisfy the FDA requirements for the approval of TPOXX ® under the Animal Rule.
Collapse
Affiliation(s)
- Michael Merchlinsky
- Biomedical Advanced Research and Development Authority, 300 C Street SW, Washington DC, 20201, USA.
| | - Andrew Albright
- Biomedical Advanced Research and Development Authority, 300 C Street SW, Washington DC, 20201, USA
| | - Victoria Olson
- National Center for Emerging and Zoonotic Infectious Disease, Centers for Disease Control and Prevention, Mail Stop G-06, 1600 Clifton Road, NE, Atlanta, 30333, Georgia
| | - Helen Schiltz
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, MSC 9825, 5601 Fishers Lane, Rockville, MD, 20851, USA
| | - Tyler Merkeley
- Biomedical Advanced Research and Development Authority, 300 C Street SW, Washington DC, 20201, USA
| | - Claiborne Hughes
- Biomedical Advanced Research and Development Authority, 300 C Street SW, Washington DC, 20201, USA
| | - Brett Petersen
- National Center for Emerging and Zoonotic Infectious Disease, Centers for Disease Control and Prevention, Mail Stop G-06, 1600 Clifton Road, NE, Atlanta, 30333, Georgia
| | - Mark Challberg
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, MSC 9825, 5601 Fishers Lane, Rockville, MD, 20851, USA
| |
Collapse
|
9
|
Current concepts in the management of biologic and chemical warfare causalities. J Trauma Acute Care Surg 2013; 75:582-9. [PMID: 24064869 DOI: 10.1097/ta.0b013e3182a11175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|