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Nair AS, Woodford J, Loughland J, Andrew D, Piera K, Amante F, William T, Grigg MJ, McCarthy JS, Anstey NM, Boyle MJ, Barber BE. Osteoprotegerin (OPG) and its ligands RANKL and TRAIL in falciparum, vivax and knowlesi malaria: correlations with disease severity, and B cell production of OPG. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.07.22.24310838. [PMID: 39108527 PMCID: PMC11302609 DOI: 10.1101/2024.07.22.24310838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Osteoprotegerin (OPG) is a soluble decoy receptor for receptor activator of NF-ƙB ligand (RANKL) and TNF-related apoptosis-inducing ligand (TRAIL), and is increasingly recognised as a marker of poor prognosis in a number of diseases. Here we demonstrate that in Malaysian adults with falciparum and vivax malaria, OPG is increased, and its ligands TRAIL and RANKL decreased, in proportion to disease severity. In volunteers experimentally infected with P. falciparum and P. vivax, RANKL was suppressed, while TRAIL was unexpectedly increased, suggesting binding of OPG to RANKL prior to TRAIL. We also demonstrate that P. falciparum stimulates B cells to produce OPG in vitro, and that B cell OPG production is increased ex vivo in patients with falciparum, vivax and knowlesi malaria. Our findings provide further evidence of the importance of the OPG/RANKL/TRAIL pathway in pathogenesis of diseases involving systemic inflammation, and may have implications for adjunctive therapies. Further evaluation of the role of B cell production of OPG in host responses to malaria and other inflammatory diseases is warranted.
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Affiliation(s)
| | - John Woodford
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, Bethesda, United States
| | - Jessica Loughland
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
- Burnet Institute, Melbourne, Australia
| | - Dean Andrew
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Kim Piera
- Menzies School of Health Research, Darwin, Australia
| | - Fiona Amante
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | | | | | - James S McCarthy
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
- Peter Doherty Institute for Infection and Immunity, Melbourne, Australia
| | | | - Michelle J Boyle
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
- Burnet Institute, Melbourne, Australia
| | - Bridget E Barber
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
- Menzies School of Health Research, Darwin, Australia
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Nandal R, Kumar D, Aggarwal N, Kumar V, Narasimhan B, Marwaha RK, Sharma PC, Kumar S, Bansal N, Chopra H, Deep A. Recent advances, challenges and updates on the development of therapeutics for malaria. EXCLI JOURNAL 2024; 23:672-713. [PMID: 38887396 PMCID: PMC11180964 DOI: 10.17179/excli2023-6856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 04/03/2024] [Indexed: 06/20/2024]
Abstract
Malaria has developed as a serious worldwide health issue as a result of the introduction of resistant Plasmodium species strains. Because of the common chemo resistance to most of the existing drugs on the market, it poses a severe health problem and significant obstacles in drug research. Malaria treatment has evolved during the last two decades in response to Plasmodium falciparum drug sensitivity and a return of the disease in tropical areas. Plasmodium falciparum is now highly resistant to the majority of antimalarial drugs. The parasite resistance drew focus to developing novel antimalarials to combat parasite resistance. The requirement for many novel antimalarial drugs in the future year necessitates adopting various drug development methodologies. Different innovative strategies for discovering antimalarial drugs are now being examined here. This review is primarily concerned with the description of newly synthesized antimalarial compounds, i.e. Tafenoquine, Cipargamin, Ferroquine, Artefenomel, DSM265, MMV390048 designed to improve the activity of pure antimalarial enantiomers. In this review, we selected the representative malarial drugs in clinical trials, classified them with detailed targets according to their action, discussed the relationship within the human trials, and generated a summative discussion with prospective expectations.
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Affiliation(s)
- Rimmy Nandal
- Shri Baba MastNath Institute of Pharmaceutical Sciences and Research, Baba Mast Nath University, Asthal Bohar, Rohtak-124001, Haryana, India
| | - Davinder Kumar
- College of Pharmacy, PGIMS University of Health Sciences, Rohtak-124001, Haryana, India
| | - Navidha Aggarwal
- MM College of Pharmacy, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala 133207, India
| | - Virender Kumar
- College of Pharmacy, PGIMS University of Health Sciences, Rohtak-124001, Haryana, India
| | | | - Rakesh Kumar Marwaha
- Department of Pharmaceutical Sciences, Maharishi Dayanand University, Rohtak 124001 Haryana, India
| | - Prabodh Chander Sharma
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Delhi Pharmaceutical Sciences and Research University, New Delhi 110017, India
| | - Surender Kumar
- Department of Chemistry, Chaudhary Bansi Lal University, Bhiwani-127021, India
| | - Nitin Bansal
- Department of Pharmaceutical Sciences, Chaudhary Bansi Lal University, Bhiwani-127021, Haryana, India
| | - Hitesh Chopra
- Department of Biosciences, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai - 602105, Tamil Nadu, India
| | - Aakash Deep
- Department of Pharmaceutical Sciences, Chaudhary Bansi Lal University, Bhiwani-127021, Haryana, India
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van der Plas JL, Kuiper VP, Bagchus WM, Bödding M, Yalkinoglu Ö, Tappert A, Seitzinger A, Spangenberg T, Bezuidenhout D, Wilkins J, Oeuvray C, Dhingra SK, Thathy V, Fidock DA, Smidt LCA, Roozen GVT, Koopman JPR, Lamers OAC, Sijtsma J, van Schuijlenburg R, Wessels E, Meij P, Kamerling IMC, Roestenberg M, Khandelwal A. Causal chemoprophylactic activity of cabamiquine against Plasmodium falciparum in a controlled human malaria infection: a randomised, double-blind, placebo-controlled study in the Netherlands. THE LANCET. INFECTIOUS DISEASES 2023; 23:1164-1174. [PMID: 37414066 DOI: 10.1016/s1473-3099(23)00212-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 03/05/2023] [Accepted: 03/24/2023] [Indexed: 07/08/2023]
Abstract
BACKGROUND Cabamiquine is a novel antimalarial that inhibits Plasmodium falciparum translation elongation factor 2. We investigated the causal chemoprophylactic activity and dose-exposure-response relationship of single oral doses of cabamiquine following the direct venous inoculation (DVI) of P falciparum sporozoites in malaria-naive, healthy volunteers. METHODS This was a phase 1b, randomised, double-blind, placebo-controlled, adaptive, dose-finding, single-centre study performed in Leiden, Netherlands. Malaria-naive, healthy adults aged 18-45 years were divided into five cohorts and randomly assigned (3:1) to receive cabamiquine or placebo. Randomisation was done by an independent statistician using codes in a permuted block schedule with a block size of four. Participants, investigators, and study personnel were masked to treatment allocation. A single, oral dose regimen of cabamiquine (200, 100, 80, 60, or 30 mg) or matching placebo was administered either at 2 h (early liver-stage) or 96 h (late liver-stage) after DVI. The primary endpoints based on a per-protocol analysis set were the number of participants who developed parasitaemia within 28 days of DVI, time to parasitaemia, number of participants with documented parasite blood-stage growth, clinical symptoms of malaria, and exposure-efficacy modelling. The impact of cabamiquine on liver stages was evaluated indirectly by the appearance of parasitaemia in the blood. The Clopper-Pearson CI (nominal 95%) was used to express the protection rate. The secondary outcomes were safety and tolerability, assessed in those who had received DVI and were administered one dose of the study intervention. The trial was prospectively registered on ClinicalTrials.gov (NCT04250363). FINDINGS Between Feb 17, 2020 and April 29, 2021, 39 healthy participants were enrolled (early liver-stage: 30 mg [n=3], 60 mg [n=6], 80 mg [n=6], 100 mg [n=3], 200 mg [n=3], pooled placebo [n=6]; late liver-stage: 60 mg [n=3], 100 mg [n=3], 200 mg [n=3], pooled placebo [n=3]). A dose-dependent causal chemoprophylactic effect was observed, with four (67%) of six participants in the 60 mg, five (83%) of six participants in the 80 mg, and all three participants in the 100 and 200 mg cabamiquine dose groups protected from parasitaemia up to study day 28, whereas all participants in the pooled placebo and 30 mg cabamiquine dose group developed parasitaemia. A single, oral dose of 100 mg cabamiquine or higher provided 100% protection against parasitaemia when administered during early or late liver-stage malaria. The median time to parasitaemia in those with early liver-stage malaria was prolonged to 15, 22, and 24 days for the 30, 60, and 80 mg dose of cabamiquine, respectively, compared with 10 days for the pooled placebo. All participants with positive parasitaemia showed documented blood-stage parasite growth, apart from one participant in the pooled placebo group and one participant in the 30 mg cabamiquine group. Most participants did not exhibit any malaria symptoms in both the early and late liver-stage groups, and those reported were mild in severity. A positive dose-exposure-efficacy relationship was established across exposure metrics. The median maximum concentration time was 1-6 h, with a secondary peak observed between 6 h and 12 h in all cabamiquine dose groups (early liver-stage). All cabamiquine doses were safe and well tolerated. Overall, 26 (96%) of 27 participants in the early liver-stage group and ten (83·3%) of 12 participants in the late liver-stage group reported at least one treatment-emergent adverse event (TEAE) with cabamiquine or placebo. Most TEAEs were of mild severity, transient, and resolved without sequelae. The most frequently reported cabamiquine-related TEAE was headache. No dose-related trends were observed in the incidence, severity, or causality of TEAEs. INTERPRETATION The results from this study show that cabamiquine has a dose-dependent causal chemoprophylactic activity. Together with previously demonstrated activity against the blood stages combined with a half-life of more than 150 h, these results indicate that cabamiquine could be developed as a single-dose monthly regimen for malaria prevention. FUNDING The healthcare business of Merck KGaA, Darmstadt, Germany.
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Affiliation(s)
- Johan L van der Plas
- Centre for Human Drug Research, Leiden, Netherlands; Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Vincent P Kuiper
- Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Wilhelmina M Bagchus
- Merck Institute for Pharmacometrics, Merck Serono (an affiliate of Merck KGaA, Darmstadt, Germany), Lausanne, Switzerland
| | | | | | - Aliona Tappert
- The healthcare business of Merck KGaA, Darmstadt, Germany
| | | | - Thomas Spangenberg
- Global Health Institute of Merck, Ares Trading (a subsidiary of Merck KGaA, Darmstadt, Germany), Eysins, Switzerland
| | - Deon Bezuidenhout
- Merck (Pty) (an affiliate of Merck KGaA, Darmstadt, Germany), Modderfontein, South Africa
| | | | - Claude Oeuvray
- Global Health Institute of Merck, Ares Trading (a subsidiary of Merck KGaA, Darmstadt, Germany), Eysins, Switzerland
| | | | - Vandana Thathy
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - David A Fidock
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, USA; Center for Malaria Therapeutics and Antimicrobial Resistance, Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | | | - Geert V T Roozen
- Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Jan Pieter R Koopman
- Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Olivia A C Lamers
- Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Jeroen Sijtsma
- Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Roos van Schuijlenburg
- Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Els Wessels
- Department of Medical Microbiology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Pauline Meij
- Center for Cell and Gene Therapy, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Ingrid M C Kamerling
- Centre for Human Drug Research, Leiden, Netherlands; Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands
| | - Meta Roestenberg
- Department of Infectious Diseases and Parasitology, Leiden University Center for Infectious Diseases, Leiden University Medical Center, Leiden, Netherlands.
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Siqueira-Neto JL, Wicht KJ, Chibale K, Burrows JN, Fidock DA, Winzeler EA. Antimalarial drug discovery: progress and approaches. Nat Rev Drug Discov 2023; 22:807-826. [PMID: 37652975 PMCID: PMC10543600 DOI: 10.1038/s41573-023-00772-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2023] [Indexed: 09/02/2023]
Abstract
Recent antimalarial drug discovery has been a race to produce new medicines that overcome emerging drug resistance, whilst considering safety and improving dosing convenience. Discovery efforts have yielded a variety of new molecules, many with novel modes of action, and the most advanced are in late-stage clinical development. These discoveries have led to a deeper understanding of how antimalarial drugs act, the identification of a new generation of drug targets, and multiple structure-based chemistry initiatives. The limited pool of funding means it is vital to prioritize new drug candidates. They should exhibit high potency, a low propensity for resistance, a pharmacokinetic profile that favours infrequent dosing, low cost, preclinical results that demonstrate safety and tolerability in women and infants, and preferably the ability to block Plasmodium transmission to Anopheles mosquito vectors. In this Review, we describe the approaches that have been successful, progress in preclinical and clinical development, and existing challenges. We illustrate how antimalarial drug discovery can serve as a model for drug discovery in diseases of poverty.
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Affiliation(s)
| | - Kathryn J Wicht
- Holistic Drug Discovery and Development (H3D) Centre, University of Cape Town, Rondebosch, South Africa
- South African Medical Research Council Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch, South Africa
| | - Kelly Chibale
- Holistic Drug Discovery and Development (H3D) Centre, University of Cape Town, Rondebosch, South Africa
- South African Medical Research Council Drug Discovery and Development Research Unit, Department of Chemistry and Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch, South Africa
| | | | - David A Fidock
- Department of Microbiology and Immunology and Center for Malaria Therapeutics and Antimicrobial Resistance, Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
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Pontikos MA, Leija C, Zhao Z, Wang X, Kilgore J, Tornesi B, Adenmatten N, Phillips MA, Williams NS. Development of a biomarker to monitor target engagement after treatment with dihydroorotate dehydrogenase inhibitors. Biochem Pharmacol 2022; 204:115237. [PMID: 36055381 PMCID: PMC9547971 DOI: 10.1016/j.bcp.2022.115237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 11/22/2022]
Abstract
Dihydroorotate dehydrogenase (DHODH) catalyzes a key step in pyrimidine biosynthesis and has recently been validated as a therapeutic target for malaria through clinical studies on the triazolopyrimidine-based Plasmodium DHODH inhibitor DSM265. Selective toxicity towards Plasmodium species could be achieved because malaria parasites lack pyrimidine salvage pathways, and DSM265 selectively inhibits Plasmodium DHODH over the human enzyme. However, while DSM265 does not inhibit human DHODH, it inhibits DHODH from several preclinical species, including mice, suggesting that toxicity could result from on-target DHODH inhibition in those species. We describe here the use of dihydroorotate (DHO) as a biomarker of DHODH inhibition. Treatment of mammalian cells with DSM265 or the mammalian DHODH inhibitor teriflunomide led to increases in DHO where the extent of biomarker buildup correlated with both dose and inhibitor potency on DHODH. Treatment of mice with leflunomide (teriflunomide prodrug) caused a large dose-dependent buildup of DHO in blood (up to 16-fold) and urine (up to 5,400-fold) that was not observed for mice treated with DSM265. Unbound plasma teriflunomide levels reached 20-85-fold above the mouse DHODH IC50, while free DSM265 levels were only 1.6-4.2-fold above, barely achieving ∼ IC90 concentrations, suggesting that unbound DSM265 plasma levels are not sufficient to block the pathway in vivo. Thus, any toxicity associated with DSM265 treatment in mice is likely caused by off-target mechanisms. The identification of a robust biomarker for mammalian DHODH inhibition represents an important advance to generally monitor for on-target effects in preclinical and clinical applications of DHODH inhibitors used to treat human disease.
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Affiliation(s)
- Michael A Pontikos
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390-9135, United States
| | - Christopher Leija
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390-9135, United States
| | - Zhiyu Zhao
- Children's Medical Center Research Institute, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390, United States
| | - Xiaoyu Wang
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390-9135, United States
| | - Jessica Kilgore
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390-9135, United States
| | - Belen Tornesi
- Medicines for Malaria Venture, 1215 Geneva, Switzerland
| | | | - Margaret A Phillips
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390-9135, United States.
| | - Noelle S Williams
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390-9135, United States.
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Marquart L, Webb L, O'Rourke P, Gatton ML, Hsiang MS, Kalnoky M, Jang IK, Ntuku H, Mumbengegwi DR, Domingo GJ, McCarthy JS, Britton S. The in-vivo dynamics of Plasmodium falciparum HRP2: implications for the use of rapid diagnostic tests in malaria elimination. Malar J 2022; 21:233. [PMID: 35922803 PMCID: PMC9351188 DOI: 10.1186/s12936-022-04245-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 07/13/2022] [Indexed: 11/24/2022] Open
Abstract
Background Rapid diagnostic tests (RDTs) that rely on the detection of Plasmodium falciparum histidine-rich protein 2 (PfHRP2) have become key tools for diagnosing P. falciparum infection. The utility of RDTs can be limited by PfHRP2 persistence, however it can be a potential benefit in low transmission settings where detection of persistent PfHRP2 using newer ultra-sensitive PfHRP2 based RDTs can serve as a surveillance tool to identify recent exposure. Better understanding of the dynamics of PfHRP2 over the course of a malaria infection can inform optimal use of RDTs. Methods A previously published mathematical model was refined to mimic the production and decay of PfHRP2 during a malaria infection. Data from 15 individuals from volunteer infection studies were used to update the original model and estimate key model parameters. The refined model was applied to a cohort of patients from Namibia who received treatment for clinical malaria infection for whom longitudinal PfHRP2 concentrations were measured. Results The refinement of the PfHRP2 dynamic model indicated that in malaria naïve hosts, P. falciparum parasites of the 3D7 strain produce 33.6 × 10−15 g (95% CI 25.0–42.1 × 10−15 g) of PfHRP2 in vivo per parasite replication cycle, with an elimination half-life of 1.67 days (95% CI 1.11–3.40 days). The refined model included these updated parameters and incorporated individualized body fluid volume calculations, which improved predictive accuracy when compared to the original model. The performance of the model in predicting clearance of PfHRP2 post treatment in clinical samples from six adults with P. falciparum infection in Namibia improved when using a longer elimination half-life of 4.5 days, with 14% to 67% of observations for each individual within the predicted range. Conclusions The updated mathematical model can predict the growth and clearance of PfHRP2 during the production and decay of a mono-infection with P. falciparum, increasing the understanding of PfHRP2 antigen dynamics. This model can guide the optimal use of PfHRP2-based RDTs for reliable diagnosis of P. falciparum infection and re-infection in endemic settings, but also for malaria surveillance and elimination programmes in low transmission areas. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04245-z.
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Affiliation(s)
- Louise Marquart
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia. .,University of Queensland, Brisbane, QLD, Australia.
| | - Lachlan Webb
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Peter O'Rourke
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | | | - Michelle S Hsiang
- Department of Pediatrics, University of Texas, Southwestern, Dallas, TX, USA.,Malaria Elimination Initiative, Institute for Global Health Services, University of California, San Francisco, CA, USA.,Department of Pediatrics, University of California, San Francisco, CA, USA
| | | | | | - Henry Ntuku
- Malaria Elimination Initiative, Institute for Global Health Services, University of California, San Francisco, CA, USA
| | | | | | - James S McCarthy
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,University of Queensland, Brisbane, QLD, Australia
| | - Sumudu Britton
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,University of Queensland, Brisbane, QLD, Australia
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7
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Komatsuya K, Sakura T, Shiomi K, Ōmura S, Hikosaka K, Nozaki T, Kita K, Inaoka DK. Siccanin Is a Dual-Target Inhibitor of Plasmodium falciparum Mitochondrial Complex II and Complex III. Pharmaceuticals (Basel) 2022; 15:ph15070903. [PMID: 35890202 PMCID: PMC9319939 DOI: 10.3390/ph15070903] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 02/05/2023] Open
Abstract
Plasmodium falciparum contains several mitochondrial electron transport chain (ETC) dehydrogenases shuttling electrons from the respective substrates to the ubiquinone pool, from which electrons are consecutively transferred to complex III, complex IV, and finally to the molecular oxygen. The antimalarial drug atovaquone inhibits complex III and validates this parasite’s ETC as an attractive target for chemotherapy. Among the ETC dehydrogenases from P. falciparum, dihydroorotate dehydrogenase, an essential enzyme used in de novo pyrimidine biosynthesis, and complex III are the two enzymes that have been characterized and validated as drug targets in the blood-stage parasite, while complex II has been shown to be essential for parasite survival in the mosquito stage; therefore, these enzymes and complex II are considered candidate drug targets for blocking parasite transmission. In this study, we identified siccanin as the first (to our knowledge) nanomolar inhibitor of the P. falciparum complex II. Moreover, we demonstrated that siccanin also inhibits complex III in the low-micromolar range. Siccanin did not inhibit the corresponding complexes from mammalian mitochondria even at high concentrations. Siccanin inhibited the growth of P. falciparum with IC50 of 8.4 μM. However, the growth inhibition of the P. falciparum blood stage did not correlate with ETC inhibition, as demonstrated by lack of resistance to siccanin in the yDHODH-3D7 (EC50 = 10.26 μM) and Dd2-ELQ300 strains (EC50 = 18.70 μM), suggesting a third mechanism of action that is unrelated to mitochondrial ETC inhibition. Hence, siccanin has at least a dual mechanism of action, being the first potent and selective inhibitor of P. falciparum complexes II and III over mammalian enzymes and so is a potential candidate for the development of a new class of antimalarial drugs.
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Affiliation(s)
- Keisuke Komatsuya
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; (K.K.); (T.N.)
- Laboratory of Biomembrane, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Takaya Sakura
- Department of Molecular Infection Dynamics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki 852-8523, Japan;
- School of Tropical Medicine and Global Health, Nagasaki University, Sakamoto, Nagasaki 852-8523, Japan
| | - Kazuro Shiomi
- Graduate School of Infection Control Sciences, Kitasato University, Tokyo 108-8641, Japan;
| | - Satoshi Ōmura
- Ōmura Satoshi Memorial Institute, Kitasato University, Minato-ku, Tokyo 108-8641, Japan;
| | - Kenji Hikosaka
- Department of Infection and Host Defense, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan;
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; (K.K.); (T.N.)
| | - Kiyoshi Kita
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; (K.K.); (T.N.)
- School of Tropical Medicine and Global Health, Nagasaki University, Sakamoto, Nagasaki 852-8523, Japan
- Department of Host-Defense Biochemistry, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki 852-8523, Japan
- Correspondence: (K.K.); (D.K.I.); Tel.: +81-95-819-7575 (K.K.); +81-95-819-7230 (D.K.I.)
| | - Daniel Ken Inaoka
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan; (K.K.); (T.N.)
- Department of Molecular Infection Dynamics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki 852-8523, Japan;
- School of Tropical Medicine and Global Health, Nagasaki University, Sakamoto, Nagasaki 852-8523, Japan
- Correspondence: (K.K.); (D.K.I.); Tel.: +81-95-819-7575 (K.K.); +81-95-819-7230 (D.K.I.)
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8
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Abstract
"The Primate Malarias" book has been a uniquely important resource for multiple generations of scientists, since its debut in 1971, and remains pertinent to the present day. Indeed, nonhuman primates (NHPs) have been instrumental for major breakthroughs in basic and pre-clinical research on malaria for over 50 years. Research involving NHPs have provided critical insights and data that have been essential for malaria research on many parasite species, drugs, vaccines, pathogenesis, and transmission, leading to improved clinical care and advancing research goals for malaria control, elimination, and eradication. Whilst most malaria scientists over the decades have been studying Plasmodium falciparum, with NHP infections, in clinical studies with humans, or using in vitro culture or rodent model systems, others have been dedicated to advancing research on Plasmodium vivax, as well as on phylogenetically related simian species, including Plasmodium cynomolgi, Plasmodium coatneyi, and Plasmodium knowlesi. In-depth study of these four phylogenetically related species over the years has spawned the design of NHP longitudinal infection strategies for gathering information about ongoing infections, which can be related to human infections. These Plasmodium-NHP infection model systems are reviewed here, with emphasis on modern systems biological approaches to studying longitudinal infections, pathogenesis, immunity, and vaccines. Recent discoveries capitalizing on NHP longitudinal infections include an advanced understanding of chronic infections, relapses, anaemia, and immune memory. With quickly emerging new technological advances, more in-depth research and mechanistic discoveries can be anticipated on these and additional critical topics, including hypnozoite biology, antigenic variation, gametocyte transmission, bone marrow dysfunction, and loss of uninfected RBCs. New strategies and insights published by the Malaria Host-Pathogen Interaction Center (MaHPIC) are recapped here along with a vision that stresses the importance of educating future experts well trained in utilizing NHP infection model systems for the pursuit of innovative, effective interventions against malaria.
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Affiliation(s)
- Mary R Galinski
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA.
- Emory Vaccine Center, Emory University, Atlanta, GA, USA.
- Emory National Primate Research Center (Yerkes National Primate Research Center), Emory University, Atlanta, GA, USA.
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9
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Barber BE, Fernandez M, Patel HB, Barcelo C, Woolley SD, Patel H, Llewellyn S, Abd-Rahman AN, Sharma S, Jain M, Ghoghari A, Di Resta I, Fuchs A, Deni I, Yeo T, Mok S, Fidock DA, Chalon S, Möhrle JJ, Parmar D, McCarthy JS, Kansagra K. Safety, pharmacokinetics, and antimalarial activity of the novel triaminopyrimidine ZY-19489: a first-in-human, randomised, placebo-controlled, double-blind, single ascending dose study, pilot food-effect study, and volunteer infection study. THE LANCET INFECTIOUS DISEASES 2022; 22:879-890. [DOI: 10.1016/s1473-3099(21)00679-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/30/2021] [Accepted: 10/13/2021] [Indexed: 01/04/2023]
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10
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Moehrle JJ. Development of New Strategies for Malaria Chemoprophylaxis: From Monoclonal Antibodies to Long-Acting Injectable Drugs. Trop Med Infect Dis 2022; 7:tropicalmed7040058. [PMID: 35448833 PMCID: PMC9024890 DOI: 10.3390/tropicalmed7040058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/18/2022] [Accepted: 03/22/2022] [Indexed: 02/04/2023] Open
Abstract
Drug discovery for malaria has traditionally focused on orally available drugs that kill the abundant, parasitic blood stage. Recently, there has also been an interest in injectable medicines, in the form of monoclonal antibodies (mAbs) with long-lasting plasma half-lives or long-lasting depot formulations of small molecules. These could act as prophylactic drugs, targeting the sporozoites and other earlier parasitic stages in the liver, when the parasites are less numerous, or as another intervention strategy targeting the formation of infectious gametocytes. Generally speaking, the development of mAbs is less risky (costly) than small-molecule drugs, and they have an excellent safety profile with few or no off-target effects. Therefore, populations who are the most vulnerable to malaria, i.e., pregnant women and young children would have access to such new treatments much faster than is presently the case for new antimalarials. An analysis of mAbs that were successfully developed for oncology illustrates some of the feasibility aspects, and their potential as affordable drugs in low- and middle-income countries.
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Affiliation(s)
- Joerg J Moehrle
- Integrated Sciences, R&D, Medicines for Malaria Venture, Route de Pré Bois 20, CH-1215 Geneva 15, Switzerland
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11
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Usui M, Williamson KC. Stressed Out About Plasmodium falciparum Gametocytogenesis. Front Cell Infect Microbiol 2021; 11:790067. [PMID: 34926328 PMCID: PMC8674873 DOI: 10.3389/fcimb.2021.790067] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 11/08/2021] [Indexed: 11/21/2022] Open
Abstract
Blocking malaria transmission is critical to malaria control programs but remains a major challenge especially in endemic regions with high levels of asymptomatic infections. New strategies targeting the transmissible sexual stages of the parasite, called gametocytes, are needed. This review focuses on P. falciparum gametocytogenesis in vivo and in vitro. Highlighting advances made elucidating genes required for gametocyte production and identifying key questions that remain unanswered such as the factors and regulatory mechanisms that contribute to gametocyte induction, and the mechanism of sequestration. Tools available to begin to address these issues are also described to facilitate advances in our understanding of this important stage of the life cycle.
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Affiliation(s)
- Miho Usui
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Kim C Williamson
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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12
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Woolley SD, Marquart L, Woodford J, Chalon S, Moehrle JJ, McCarthy JS, Barber BE. Haematological response in experimental human Plasmodium falciparum and Plasmodium vivax malaria. Malar J 2021; 20:470. [PMID: 34930260 PMCID: PMC8685492 DOI: 10.1186/s12936-021-04003-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/01/2021] [Indexed: 11/25/2022] Open
Abstract
Background Malaria-associated anaemia, arising from symptomatic, asymptomatic and submicroscopic infections, is a significant cause of morbidity worldwide. Induced blood stage malaria volunteer infection studies (IBSM-VIS) provide a unique opportunity to evaluate the haematological response to early Plasmodium falciparum and Plasmodium vivax infection. Methods This study was an analysis of the haemoglobin, red cell counts, and parasitaemia data from 315 participants enrolled in IBSM-VIS between 2012 and 2019, including 269 participants inoculated with the 3D7 strain of P. falciparum (Pf3D7), 15 with an artemisinin-resistant P. falciparum strain (PfK13) and 46 with P. vivax. Factors associated with the fractional fall in haemoglobin (Hb-FF) were evaluated, and the malaria-attributable erythrocyte loss after accounting for phlebotomy-related losses was estimated. The relative contribution of parasitized erythrocytes to the malaria-attributable erythrocyte loss was also estimated. Results The median peak parasitaemia prior to treatment was 10,277 parasites/ml (IQR 3566–27,815), 71,427 parasites/ml [IQR 33,236–180,213], and 34,840 parasites/ml (IQR 13,302–77,064) in participants inoculated with Pf3D7, PfK13, and P. vivax, respectively. The median Hb-FF was 10.3% (IQR 7.8–13.3), 14.8% (IQR 11.8–15.9) and 11.7% (IQR 8.9–14.5) in those inoculated with Pf3D7, PfK13 and P. vivax, respectively, with the haemoglobin nadir occurring a median 12 (IQR 5–21), 15 (IQR 7–22), and 8 (IQR 7–15) days following inoculation. In participants inoculated with P. falciparum, recrudescence was associated with a greater Hb-FF, while in those with P. vivax, the Hb-FF was associated with a higher pre-treatment parasitaemia and later day of anti-malarial treatment. After accounting for phlebotomy-related blood losses, the estimated Hb-FF was 4.1% (IQR 3.1–5.3), 7.2% (IQR 5.8–7.8), and 4.9% (IQR 3.7–6.1) in participants inoculated with Pf3D7, PfK13, and P. vivax, respectively. Parasitized erythrocytes were estimated to account for 0.015% (IQR 0.006–0.06), 0.128% (IQR 0.068–0.616) and 0.022% (IQR 0.008–0.082) of the malaria-attributable erythrocyte loss in participants inoculated with Pf3D7, PfK13, and P. vivax, respectively. Conclusion Early experimental P. falciparum and P. vivax infection resulted in a small but significant fall in haemoglobin despite parasitaemia only just at the level of microscopic detection. Loss of parasitized erythrocytes accounted for < 0.2% of the total malaria-attributable haemoglobin loss. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-04003-7.
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13
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McCarthy JS, Yalkinoglu Ö, Odedra A, Webster R, Oeuvray C, Tappert A, Bezuidenhout D, Giddins MJ, Dhingra SK, Fidock DA, Marquart L, Webb L, Yin X, Khandelwal A, Bagchus WM. Safety, pharmacokinetics, and antimalarial activity of the novel plasmodium eukaryotic translation elongation factor 2 inhibitor M5717: a first-in-human, randomised, placebo-controlled, double-blind, single ascending dose study and volunteer infection study. THE LANCET. INFECTIOUS DISEASES 2021; 21:1713-1724. [PMID: 34715032 PMCID: PMC8612936 DOI: 10.1016/s1473-3099(21)00252-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 03/02/2021] [Accepted: 04/13/2021] [Indexed: 01/28/2023]
Abstract
BACKGROUND M5717 is the first plasmodium translation elongation factor 2 inhibitor to reach clinical development as an antimalarial. We aimed to characterise the safety, pharmacokinetics, and antimalarial activity of M5717 in healthy volunteers. METHODS This first-in-human study was a two-part, single-centre clinical trial done in Brisbane, QLD, Australia. Part one was a double-blind, randomised, placebo-controlled, single ascending dose study in which participants were enrolled into one of nine dose cohorts (50, 100, 200, 400, 600, 1000, 1250, 1800, or 2100 mg) and randomly assigned (3:1) to M5717 or placebo. A sentinel dosing strategy was used for each dose cohort whereby two participants (one assigned to M5717 and one assigned to placebo) were initially randomised and dosed. Randomisation schedules were generated electronically by independent, unblinded statisticians. Part two was an open-label, non-randomised volunteer infection study using the Plasmodium falciparum induced blood-stage malaria model in which participants were enrolled into three dose cohorts. Healthy men and women of non-childbearing potential aged 18-55 years were eligible for inclusion; individuals in the volunteer infection study were required to be malaria naive. Safety and tolerability (primary outcome of the single ascending dose study and secondary outcome of the volunteer infection study) were assessed by frequency and severity of adverse events. The pharmacokinetic profile of M5717 was also characterised (primary outcome of the volunteer infection study and secondary outcome of the single ascending dose study). Parasite clearance kinetics (primary outcome of the volunteer infection study) were assessed by the parasite reduction ratio and the corresponding parasite clearance half-life; the incidence of recrudescence up to day 28 was determined (secondary outcome of the volunteer infection study). Recrudescent parasites were tested for genetic mutations (exploratory outcome). The trial is registered with ClinicalTrials.gov (NCT03261401). FINDINGS Between Aug 28, 2017, and June 14, 2019, 221 individuals were assessed for eligibility, of whom 66 men were enrolled in the single ascending dose study (eight per cohort for 50-1800 mg cohorts, randomised three M5717 to one placebo, and two in the 2100 mg cohort, randomised one M5717 to one placebo) and 22 men were enrolled in the volunteer infection study (six in the 150 mg cohort and eight each in the 400 mg and 800 mg cohorts). No adverse event was serious; all M5717-related adverse events were mild or moderate in severity and transient, with increased frequency observed at doses above 1250 mg. In the single ascending dose study, treatment-related adverse events occurred in three of 17 individuals in the placebo group; no individual in the 50 mg, 100 mg, or 200 mg groups; one of six individuals in each of the 400 mg, 1000 mg, and 1250 mg groups; two of six individuals in the 600 mg group; and in all individuals in the 1800 mg and 2100 mg groups. In the volunteer infection study, M5717-related adverse events occurred in no participants in the 150 mg or 800 mg groups and in one of eight participants in the 400 mg group. Transient oral hypoesthesia (in three participants) and blurred vision (in four participants) were observed in the 1800 mg or 2100 mg groups and constituted an unknown risk; thus, further dosing was suspended after dosing of the two sentinel individuals in the 2100 mg cohort. Maximum blood concentrations occurred 1-7 h after dosing, and a long half-life was observed (146-193 h at doses ≥200 mg). Parasite clearance occurred in all participants and was biphasic, characterised by initial slow clearance lasting 35-55 h (half-life 231·1 h [95% CI 40·9 to not reached] for 150 mg, 60·4 h [38·6 to 138·6] for 400 mg, and 24·7 h [20·4 to 31·3] for 800 mg), followed by rapid clearance (half-life 3·5 h [3·1 to 4·0] for 150 mg, 3·9 h [3·3 to 4·8] for 400 mg, and 5·5 h [4·8 to 6·4] for 800 mg). Recrudescence occurred in three (50%) of six individuals dosed with 150 mg and two (25%) of eight individuals dosed with 400 mg. Genetic mutations associated with resistance were detected in four cases of parasite recrudescence (two individuals dosed with 150 mg and two dosed with 400 mg). INTERPRETATION The safety, pharmacokinetics, and antimalarial activity of M5717 support its development as a component of a single-dose antimalarial combination therapy or for malaria prophylaxis. FUNDING Wellcome Trust and the healthcare business of Merck KGaA, Darmstadt, Germany.
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Affiliation(s)
- James S McCarthy
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and the Royal Melbourne Hospital, Melbourne, VIC, Australia
| | | | - Anand Odedra
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; Liverpool School of Tropical Medicine, Liverpool, UK
| | - Rebecca Webster
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Claude Oeuvray
- The Global Health Institute of Merck (an affiliate of Merck KGaA), Eysin, Switzerland
| | - Aliona Tappert
- the healthcare business of Merck KGaA, Darmstadt, Germany
| | | | - Marla J Giddins
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - Satish K Dhingra
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA; Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - Louise Marquart
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Lachlan Webb
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Xiaoyan Yin
- Global Statistics for NDD, Immunology, Endocrinology, Fertility & Others, EMD Serono, Billerica, MA, USA
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14
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Antimalarial drug candidates in phase I and II drug development: a scoping review. Antimicrob Agents Chemother 2021; 66:e0165921. [PMID: 34843390 PMCID: PMC8846400 DOI: 10.1128/aac.01659-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The emergence and spread of parasite resistance to currently available antimalarials has highlighted the importance of developing novel antimalarials. This scoping review provides an overview of antimalarial drug candidates undergoing phase I and II studies between 1 January 2016 and 28 April 2021. PubMed, Web of Science, Embase, clinical trial registries, and reference lists were searched for relevant studies. Information regarding antimalarial compound details, clinical trial characteristics, study population, and drug pharmacokinetics and pharmacodynamics (PK-PD) were extracted. A total of 50 studies were included, of which 24 had published their results and 26 were unpublished. New antimalarial compounds were evaluated as monotherapy (28 studies, 14 drug candidates) and combination therapy (9 studies, 10 candidates). Fourteen active compounds were identified in the current antimalarial drug development pipeline together with 11 compounds that are inactive, 6 due to insufficient efficacy. PK-PD data were available from 24 studies published as open-access articles. Four unpublished studies have made their results publicly available on clinical trial registries. The terminal elimination half-life of new antimalarial compounds ranged from 14.7 to 483 h. The log10 parasite reduction ratio over 48 h and parasite clearance half-life for Plasmodium falciparum following a single-dose monotherapy were 1.55 to 4.1 and 3.4 to 9.4 h, respectively. The antimalarial drug development landscape has seen a number of novel compounds, with promising PK-PD properties, evaluated in phase I and II studies over the past 5 years. Timely public disclosure of PK-PD data is crucial for informative decision-making and drug development strategy.
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15
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Webster R, Sekuloski S, Odedra A, Woolley S, Jennings H, Amante F, Trenholme KR, Healer J, Cowman AF, Eriksson EM, Sathe P, Penington J, Blanch AJ, Dixon MWA, Tilley L, Duffy MF, Craig A, Storm J, Chan JA, Evans K, Papenfuss AT, Schofield L, Griffin P, Barber BE, Andrew D, Boyle MJ, de Labastida Rivera F, Engwerda C, McCarthy JS. Safety, infectivity and immunogenicity of a genetically attenuated blood-stage malaria vaccine. BMC Med 2021; 19:293. [PMID: 34802442 PMCID: PMC8606250 DOI: 10.1186/s12916-021-02150-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 09/30/2021] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND There is a clear need for novel approaches to malaria vaccine development. We aimed to develop a genetically attenuated blood-stage vaccine and test its safety, infectivity, and immunogenicity in healthy volunteers. Our approach was to target the gene encoding the knob-associated histidine-rich protein (KAHRP), which is responsible for the assembly of knob structures at the infected erythrocyte surface. Knobs are required for correct display of the polymorphic adhesion ligand P. falciparum erythrocyte membrane protein 1 (PfEMP1), a key virulence determinant encoded by a repertoire of var genes. METHODS The gene encoding KAHRP was deleted from P. falciparum 3D7 and a master cell bank was produced in accordance with Good Manufacturing Practice. Eight malaria naïve males were intravenously inoculated (day 0) with 1800 (2 subjects), 1.8 × 105 (2 subjects), or 3 × 106 viable parasites (4 subjects). Parasitemia was measured using qPCR; immunogenicity was determined using standard assays. Parasites were rescued into culture for in vitro analyses (genome sequencing, cytoadhesion assays, scanning electron microscopy, var gene expression). RESULTS None of the subjects who were administered with 1800 or 1.8 × 105 parasites developed parasitemia; 3/4 subjects administered 3× 106 parasites developed significant parasitemia, first detected on days 13, 18, and 22. One of these three subjects developed symptoms of malaria simultaneously with influenza B (day 17; 14,022 parasites/mL); one subject developed mild symptoms on day 28 (19,956 parasites/mL); and one subject remained asymptomatic up to day 35 (5046 parasites/mL). Parasitemia rapidly cleared with artemether/lumefantrine. Parasitemia induced a parasite-specific antibody and cell-mediated immune response. Parasites cultured ex vivo exhibited genotypic and phenotypic properties similar to inoculated parasites, although the var gene expression profile changed during growth in vivo. CONCLUSIONS This study represents the first clinical investigation of a genetically attenuated blood-stage human malaria vaccine. A P. falciparum 3D7 kahrp- strain was tested in vivo and found to be immunogenic but can lead to patent parasitemia at high doses. TRIAL REGISTRATION Australian New Zealand Clinical Trials Registry (number: ACTRN12617000824369 ; date: 06 June 2017).
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Affiliation(s)
- Rebecca Webster
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Silvana Sekuloski
- QIMR Berghofer Medical Research Institute, Brisbane, Australia.,Current address: PharmOut, 111 Eagle Street, Brisbane, Queensland, 4000, Australia
| | - Anand Odedra
- QIMR Berghofer Medical Research Institute, Brisbane, Australia.,Liverpool School of Tropical Medicine, Liverpool, UK
| | - Stephen Woolley
- QIMR Berghofer Medical Research Institute, Brisbane, Australia.,Liverpool School of Tropical Medicine, Liverpool, UK.,Centre of Defence Pathology, Royal Centre for Defence Medicine, Joint Hospital Group, Birmingham, UK
| | - Helen Jennings
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Fiona Amante
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Katharine R Trenholme
- QIMR Berghofer Medical Research Institute, Brisbane, Australia.,The University of Queensland, Brisbane, Australia
| | - Julie Healer
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Alan F Cowman
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Emily M Eriksson
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Priyanka Sathe
- Current address: Medicines Development for Global Health Limited, 18 Kavanagh Street, Southbank, Victoria, 3006, Australia
| | - Jocelyn Penington
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Adam J Blanch
- Bio21 Molecular Science and Biotechnology Institute, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Australia
| | - Matthew W A Dixon
- Bio21 Molecular Science and Biotechnology Institute, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Australia
| | - Leann Tilley
- Bio21 Molecular Science and Biotechnology Institute, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Australia
| | - Michael F Duffy
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia.,Bio21 Molecular Science and Biotechnology Institute, Melbourne, Australia.,The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia.,Department of Medicine, Royal Melbourne Hospital, Melbourne, Australia
| | - Alister Craig
- Liverpool School of Tropical Medicine, Liverpool, UK
| | - Janet Storm
- Liverpool School of Tropical Medicine, Liverpool, UK
| | | | - Krystal Evans
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Current address: GSK, 436 Johnston Street, Abbotsford, Victoria, 3067, Australia
| | - Anthony T Papenfuss
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Louis Schofield
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.,Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
| | - Paul Griffin
- QIMR Berghofer Medical Research Institute, Brisbane, Australia.,The University of Queensland, Brisbane, Australia.,Department of Medicine and Infectious Diseases, Mater Hospital and Mater Research, Brisbane, Australia
| | | | - Dean Andrew
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | | | | | | | - James S McCarthy
- QIMR Berghofer Medical Research Institute, Brisbane, Australia. .,The Peter Doherty Institute for Infection and Immunity, Melbourne, Australia.
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16
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Fernandes VDS, da Rosa R, Zimmermann LA, Rogério KR, Kümmerle AE, Bernardes LSC, Graebin CS. Antiprotozoal agents: How have they changed over a decade? Arch Pharm (Weinheim) 2021; 355:e2100338. [PMID: 34661935 DOI: 10.1002/ardp.202100338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 09/29/2021] [Accepted: 09/30/2021] [Indexed: 12/21/2022]
Abstract
Neglected tropical diseases are a diverse group of communicable diseases that are endemic in low- or low-to-middle-income countries located in tropical and subtropical zones. The number and availability of drugs for treating these diseases are low, the administration route is inconvenient in some cases, and most of them have safety, efficacy, or adverse/toxic reaction issues. The need for developing new drugs to deal with these issues is clear, but one of the most drastic consequences of this negligence is the lack of interest in the research and development of new therapeutic options among major pharmaceutical companies. Positive changes have been achieved over the last few years, although the overall situation remains alarming. After more than one decade since the original work reviewing antiprotozoal agents came to light, now it is time to question ourselves: How has the scenario for the treatment of protozoal diseases such as malaria, leishmaniasis, human African trypanosomiasis, and American trypanosomiasis changed? This review covers the last decade in terms of the drugs currently available for the treatment of these diseases as well as the clinical candidates being currently investigated.
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Affiliation(s)
- Vitória de Souza Fernandes
- Department of Pharmaceutical Sciences, Pharmaceutical and Medicinal Chemistry Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Rafael da Rosa
- Department of Organic Chemistry, Medicinal Chemistry and Molecular Diversity Laboratory, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Lara A Zimmermann
- Department of Organic Chemistry, Medicinal Chemistry and Molecular Diversity Laboratory, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Kamilla R Rogério
- Department of Pharmaceutical Sciences, Pharmaceutical and Medicinal Chemistry Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Arthur E Kümmerle
- Department of Pharmaceutical Sciences, Pharmaceutical and Medicinal Chemistry Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Lilian S C Bernardes
- Department of Organic Chemistry, Medicinal Chemistry and Molecular Diversity Laboratory, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Cedric S Graebin
- Department of Pharmaceutical Sciences, Pharmaceutical and Medicinal Chemistry Laboratory, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil
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17
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Dini S, Zaloumis SG, Price DJ, Gobeau N, Kümmel A, Cherkaoui M, Moehrle JJ, McCarthy JS, Simpson JA. Seeking an optimal dosing regimen for OZ439/DSM265 combination therapy for treating uncomplicated falciparum malaria. J Antimicrob Chemother 2021; 76:2325-2334. [PMID: 34179977 DOI: 10.1093/jac/dkab181] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 05/02/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The efficacy of artemisinin-based combination therapies (ACTs), the first-line treatments for uncomplicated falciparum malaria, has been declining in malaria-endemic countries due to the emergence of malaria parasites resistant to these compounds. Novel alternative therapies are needed urgently to prevent the likely surge in morbidity and mortality due to failing ACTs. OBJECTIVES This study investigates the efficacy of the combination of two novel drugs, OZ439 and DSM265, using a biologically informed within-host mathematical model. METHODS A within-host model was developed, which accounts for the differential killing of these compounds against different stages of the parasite's life cycle and accommodates the pharmacodynamic interaction between the drugs. Data of healthy volunteers infected with falciparum malaria collected from four trials (three that administered OZ439 and DSM265 alone, and the fourth a combination of OZ439 and DSM265) were analysed. Model parameters were estimated in a hierarchical Bayesian framework. RESULTS The posterior predictive simulations of our model predicted that 800 mg of OZ439 combined with 450 mg of DSM265, which are within the safe and tolerable dose range, can provide above 90% cure rates 42 days after drug administration. CONCLUSIONS Our results show that the combination of OZ439 and DSM265 can be a promising alternative to replace ACTs. Our model can be used to inform future Phase 2 and 3 clinical trials of OZ439/DSM265, fast-tracking the deployment of this combination therapy in the regions where ACTs are failing. The dosing regimens that are shown to be efficacious and within safe and tolerable limits are suggested for future investigations.
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Affiliation(s)
- Saber Dini
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
| | - Sophie G Zaloumis
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
| | - David J Price
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia.,Doherty Institute for Infection and Immunity, University of Melbourne and Royal Melbourne Hospital, Melbourne, Australia
| | | | | | | | | | - James S McCarthy
- Doherty Institute for Infection and Immunity, University of Melbourne and Royal Melbourne Hospital, Melbourne, Australia.,QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
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18
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Sharma N, Kashif M, Singh V, Fontinha D, Mukherjee B, Kumar D, Singh S, Prudencio M, Singh AP, Rathi B. Novel Antiplasmodial Compounds Leveraged with Multistage Potency against the Parasite Plasmodium falciparum: In Vitro and In Vivo Evaluations and Pharmacokinetic Studies. J Med Chem 2021; 64:8666-8683. [PMID: 34124905 DOI: 10.1021/acs.jmedchem.1c00659] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydroxyethylamine (HEA)-based novel compounds were synthesized and their activity against Plasmodium falciparum 3D7 was assessed, identifying a few hits without any apparent toxicity. Hits 5c and 5d also exhibited activity against resistant field strains, PfRKL-9 and PfC580Y. A single dose, 50 mg/Kg, of hits administered to the rodent parasite Plasmodium berghei ANKA exhibited up to 70% reduction in the parasite load. Compound 5d tested in combination with artesunate produced an additional antiparasitic effect with a prolonged survival period. Additionally, compound 5d showed 50% inhibition against hepatic P. berghei infection at 1.56 ± 0.56 μM concentration. This compound also considerably delayed the progression of transmission stages, ookinete and oocyst. Furthermore, the toxicity of 5d assessed in mice supported the normal liver and kidney functions. Altogether, HEA analogues (5a-m), particularly 5d, are nontoxic multistage antiplasmodial agents with therapeutic and transmission-blocking efficacy, along with favorable preliminary pharmacokinetic properties.
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Affiliation(s)
- Neha Sharma
- Laboratory for Translational Chemistry and Drug Discovery, Department of Chemistry, Hansraj College University Enclave, University of Delhi, Delhi 110007, India
| | - Mohammad Kashif
- Infectious Diseases Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Vigyasa Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | - Diana Fontinha
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, Lisboa 1649-028, Portugal
| | - Budhaditya Mukherjee
- School of Medical Science and Technology, IIT Kharagpur, Kharagpur 721302, India
| | - Dhruv Kumar
- Amity Institute of Molecular Medicine & Stem Cell Research, Amity University, Noida 201301, Uttar Pradesh, India
| | - Shailja Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | - Miguel Prudencio
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, Lisboa 1649-028, Portugal
| | - Agam P Singh
- Infectious Diseases Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Brijesh Rathi
- Laboratory for Translational Chemistry and Drug Discovery, Department of Chemistry, Hansraj College University Enclave, University of Delhi, Delhi 110007, India
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19
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Abstract
Plasmodium vivax bench research greatly lags behind Plasmodium falciparum because of an inability to culture in vitro. A century ago, intentionally inducing a malaria infection was a strategy commonly used to cure late-stage syphilis. These controlled human malaria infections were used with expertise and persisted to the end of World War II. While controlled malaria liver-stage infection has been achieved for both P. vivax and P. falciparum, controlled human transmission to mosquitoes falls short for both species. In this issue of the JCI, Collins et al. present groundbreaking work that establishes a system to transmit P. vivax gametocytes from humans to mosquitoes. The authors injected a unique human isolate of P. vivax that reached high gametocyte density within weeks. This study provides a technical advance that will facilitate the study and eradication of the human parasite P. vivax.
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20
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Defining the Antimalarial Activity of Cipargamin in Healthy Volunteers Experimentally Infected with Blood-Stage Plasmodium falciparum. Antimicrob Agents Chemother 2021; 65:AAC.01423-20. [PMID: 33199389 PMCID: PMC7849011 DOI: 10.1128/aac.01423-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 11/08/2020] [Indexed: 12/11/2022] Open
Abstract
The spiroindolone cipargamin, a new antimalarial compound that inhibits Plasmodium ATP4, is currently in clinical development. This study aimed to characterize the antimalarial activity of cipargamin in healthy volunteers experimentally infected with blood-stage Plasmodium falciparum. The spiroindolone cipargamin, a new antimalarial compound that inhibits Plasmodium ATP4, is currently in clinical development. This study aimed to characterize the antimalarial activity of cipargamin in healthy volunteers experimentally infected with blood-stage Plasmodium falciparum. Eight subjects were intravenously inoculated with parasite-infected erythrocytes and received a single oral dose of 10 mg cipargamin 7 days later. Blood samples were collected to monitor the development and clearance of parasitemia and plasma cipargamin concentrations. Parasite regrowth was treated with piperaquine monotherapy to clear asexual parasites, while allowing gametocyte transmissibility to mosquitoes to be investigated. An initial rapid decrease in parasitemia occurred in all participants following cipargamin dosing, with a parasite clearance half-life of 3.99 h. As anticipated from the dose selected, parasite regrowth occurred in all 8 subjects 3 to 8 days after dosing and allowed the pharmacokinetic/pharmacodynamic relationship to be determined. Based on the limited data from the single subtherapeutic dose cohort, a MIC of 11.6 ng/ml and minimum parasiticidal concentration that achieves 90% of maximum effect of 23.5 ng/ml were estimated, and a single 95-mg dose (95% confidence interval [CI], 50 to 270) was predicted to clear 109 parasites/ml. Low gametocyte densities were detected in all subjects following piperaquine treatment, which did not transmit to mosquitoes. Serious adverse liver function changes were observed in three subjects, which led to premature study termination. The antimalarial activity characterized in this study supports the further clinical development of cipargamin as a new treatment for P. falciparum malaria, although the hepatic safety profile of the compound warrants further evaluation. (This study has been registered at ClinicalTrials.gov under identifier NCT02543086.)
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21
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Safety and feasibility of apheresis to harvest and concentrate parasites from subjects with induced blood stage Plasmodium vivax infection. Malar J 2021; 20:43. [PMID: 33446191 PMCID: PMC7807416 DOI: 10.1186/s12936-021-03581-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 01/04/2021] [Indexed: 11/27/2022] Open
Abstract
Background In the absence of a method to culture Plasmodium vivax, the only way to source parasites is ex vivo. This hampers many aspects of P. vivax research. This study aimed to assess the safety of apheresis, a method for selective removal of specific components of blood as a means of extracting and concentrating P. vivax parasites. Methods An iterative approach was employed across four non-immune healthy human subjects in single subject cohorts. All four subjects were inoculated with ~ 564 blood stage P. vivax (HMP013-Pv) and subjected to apheresis 10 to 11 days later. Blood samples collected during apheresis (haematocrit layers 0.5% to 11%) were tested for the presence and concentration of P. vivax by microscopy, flow cytometry, 18S rDNA qPCR for total parasites, and pvs25 qRT-PCR for female gametocyte transcripts. Safety was determined by monitoring adverse events. Malaria transmission to mosquitoes was assessed by membrane feeding assays. Results There were no serious adverse events and no significant safety concerns. Apheresis concentrated asexual parasites by up to 4.9-fold (range: 0.9–4.9-fold) and gametocytes by up to 1.45-fold (range: 0.38–1.45-fold) compared to pre-apheresis densities. No single haematocrit layer contained > 40% of all the recovered P. vivax asexual parasites. Ex vivo concentration of parasites by Percoll gradient centrifugation of whole blood achieved greater concentration of gametocytes than apheresis. Mosquito transmission was enhanced by up to fivefold in a single apheresis sample compared to pre-apheresis. Conclusion The modest level of parasite concentration suggests that the use of apheresis may not be an ideal method for harvesting P. vivax. Trial Registration Australia New Zealand Clinical Trials Registry (ANZCTR) Trial ID: ACTRN12617001502325 registered on 19th October 2017. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373812.
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22
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Sato D, Hartuti ED, Inaoka DK, Sakura T, Amalia E, Nagahama M, Yoshioka Y, Tsuji N, Nozaki T, Kita K, Harada S, Matsubayashi M, Shiba T. Structural and Biochemical Features of Eimeria tenella Dihydroorotate Dehydrogenase, a Potential Drug Target. Genes (Basel) 2020; 11:genes11121468. [PMID: 33297567 PMCID: PMC7762340 DOI: 10.3390/genes11121468] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/03/2020] [Accepted: 12/04/2020] [Indexed: 12/23/2022] Open
Abstract
Dihydroorotate dehydrogenase (DHODH) is a mitochondrial monotopic membrane protein that plays an essential role in the pyrimidine de novo biosynthesis and electron transport chain pathways. In Eimeria tenella, an intracellular apicomplexan parasite that causes the most severe form of chicken coccidiosis, the activity of pyrimidine salvage pathway at the intracellular stage is negligible and it relies on the pyrimidine de novo biosynthesis pathway. Therefore, the enzymes of the de novo pathway are considered potential drug target candidates for the design of compounds with activity against this parasite. Although, DHODHs from E. tenella (EtDHODH), Plasmodium falciparum (PfDHODH), and human (HsDHODH) show distinct sensitivities to classical DHODH inhibitors, in this paper, we identify ferulenol as a potent inhibitor of both EtDHODH and HsDHODH. Additionally, we report the crystal structures of EtDHODH and HsDHODH in the absence and presence of ferulenol. Comparison of these enzymes showed that despite similar overall structures, the EtDHODH has a long insertion in the N-terminal helix region that assumes a disordered configuration. In addition, the crystal structures revealed that the ferulenol binding pocket of EtDHODH is larger than that of HsDHODH. These differences can be explored to accelerate structure-based design of inhibitors specifically targeting EtDHODH.
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Affiliation(s)
- Dan Sato
- Department of Applied Biology, Graduate School of Science Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (D.S.); (M.N.); (Y.Y.); (S.H.)
| | - Endah Dwi Hartuti
- Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan;
| | - Daniel Ken Inaoka
- Department of Molecular Infection Dynamics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan;
- School of Tropical Medicine and Global Health, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan;
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; (E.A.); (T.N.)
- Correspondence: (D.K.I.); (T.S.); Tel.: +81-95-819-7230 (D.K.I.); Tel./Fax: +81-75-724-7541 (T.S.)
| | - Takaya Sakura
- Department of Molecular Infection Dynamics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan;
- School of Tropical Medicine and Global Health, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan;
| | - Eri Amalia
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; (E.A.); (T.N.)
| | - Madoka Nagahama
- Department of Applied Biology, Graduate School of Science Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (D.S.); (M.N.); (Y.Y.); (S.H.)
| | - Yukina Yoshioka
- Department of Applied Biology, Graduate School of Science Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (D.S.); (M.N.); (Y.Y.); (S.H.)
| | - Naotoshi Tsuji
- Department of Parasitology, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa 252-0374, Japan;
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; (E.A.); (T.N.)
| | - Kiyoshi Kita
- School of Tropical Medicine and Global Health, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan;
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; (E.A.); (T.N.)
- Department of Host-Defense Biochemistry, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Shigeharu Harada
- Department of Applied Biology, Graduate School of Science Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (D.S.); (M.N.); (Y.Y.); (S.H.)
| | - Makoto Matsubayashi
- Division of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku Orai Kita, Izumisano, Osaka 598-8531, Japan;
| | - Tomoo Shiba
- Department of Applied Biology, Graduate School of Science Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan; (D.S.); (M.N.); (Y.Y.); (S.H.)
- Correspondence: (D.K.I.); (T.S.); Tel.: +81-95-819-7230 (D.K.I.); Tel./Fax: +81-75-724-7541 (T.S.)
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23
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Odedra A, Webb L, Marquart L, Britton LJ, Chalon S, Moehrle JJ, Anstey NM, William T, Grigg MJ, Lalloo DG, Barber BE, McCarthy JS. Liver Function Test Abnormalities in Experimental and Clinical Plasmodium vivax Infection. Am J Trop Med Hyg 2020; 103:1910-1917. [PMID: 32815508 PMCID: PMC7646782 DOI: 10.4269/ajtmh.20-0491] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Liver transaminase elevations after treatment in malaria volunteer infection studies (VISs) have raised safety concerns. We investigated transaminase elevations from two human Plasmodium vivax VISs where subjects were treated with chloroquine (n = 24) or artefenomel (n = 8) and compared them with studies in Thailand (n = 41) and Malaysia (n = 76). In the VISs, alanine transaminase (ALT) increased to ≥ 2.5 × upper limit of normal (ULN) in 11/32 (34%) volunteers, peaking 5–8 days post-treatment. Transaminase elevations were asymptomatic, were not associated with elevated bilirubin, and resolved by day 42. The risk of an ALT ≥ 2.5 × ULN increased more than 4-fold (odds ratio [OR] 4.28; 95% CI: 1.26–14.59; P = 0.02) for every log10 increase in the parasite clearance burden (PCB), defined as the log-fold reduction in parasitemia 24 hours post-treatment. Although an elevated ALT ≥ 2.5 × ULN was more common after artefenomel than after chloroquine (5/8 [63%] versus 6/24 [25%]; OR 5.0; 95% CI: 0.91–27.47; P = 0.06), this risk disappeared when corrected for PCB. Peak ALT also correlated with peak C-reactive protein (R = 0.44; P = 0.012). Elevations in ALT (≥ 2.5 × ULN) were less common in malaria-endemic settings, occurring in 1/41 (2.5%) Thai patients treated with artefenomel, and in none of 76 Malaysians treated with chloroquine or artemisinin combination therapy. Post-treatment transaminase elevations are common in experimental P. vivax infection but do not appear to impact on participant safety. Although the mechanism of these changes remains uncertain, host inflammatory response to parasite clearance may be contributory.
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Affiliation(s)
- Anand Odedra
- QIMR Berghofer Medical Research Institute, Brisbane, Australia.,Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Lachlan Webb
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Louise Marquart
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Laurence J Britton
- School of Medicine, The University of Queensland, Brisbane, Australia.,Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, Brisbane, Australia
| | | | | | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Australia
| | - Timothy William
- Gleneagles Hospital, Kota Kinabalu, Malaysia.,Clinical Research Centre, Queen Elizabeth Hospital, Kota Kinabalu, Malaysia
| | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Australia
| | - David G Lalloo
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Australia.,QIMR Berghofer Medical Research Institute, Brisbane, Australia
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24
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Fisher N, Meunier B, Biagini GA. The cytochrome bc 1 complex as an antipathogenic target. FEBS Lett 2020; 594:2935-2952. [PMID: 32573760 DOI: 10.1002/1873-3468.13868] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 05/31/2020] [Accepted: 06/10/2020] [Indexed: 12/15/2022]
Abstract
The cytochrome bc1 complex is a key component of the mitochondrial respiratory chains of many eukaryotic microorganisms that are pathogenic for plants or humans, such as fungi responsible for crop diseases and Plasmodium falciparum, which causes human malaria. Cytochrome bc1 is an enzyme that contains two (ubi)quinone/quinol-binding sites, which can be exploited for the development of fungicidal and chemotherapeutic agents. Here, we review recent progress in determination of the structure and mechanism of action of cytochrome bc1 , and the associated development of antimicrobial agents (and associated resistance mechanisms) targeting its activity.
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Affiliation(s)
- Nicholas Fisher
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
| | - Brigitte Meunier
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Giancarlo A Biagini
- Parasitology Department, Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, UK
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25
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Early Endothelial Activation Precedes Glycocalyx Degradation and Microvascular Dysfunction in Experimentally Induced Plasmodium falciparum and Plasmodium vivax Infection. Infect Immun 2020; 88:IAI.00895-19. [PMID: 32122938 DOI: 10.1128/iai.00895-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 02/25/2020] [Indexed: 12/13/2022] Open
Abstract
Endothelial activation and microvascular dysfunction are key pathogenic processes in severe malaria. We evaluated the early role of these processes in experimentally induced Plasmodium falciparum and P. vivax infection. Participants were enrolled in induced blood-stage malaria clinical trials. Plasma osteoprotegerin, angiopoietin-2, and von Willebrand Factor (vWF) levels were measured as biomarkers of endothelial activation. Microvascular function was assessed using peripheral arterial tonometry and near-infrared spectroscopy, and the endothelial glycocalyx was assessed by sublingual videomicroscopy and measurement of biomarkers of degradation. Forty-five healthy, malaria-naive participants were recruited from 5 studies. Osteoprotegerin and vWF levels increased in participants following inoculation with P. vivax (n = 16) or P. falciparum (n = 15), with the angiopoietin-2 level also increasing in participants following inoculation with P. falciparum For both species, the most pronounced increase was seen in osteoprotegerin. This was particularly marked in participants inoculated with P. vivax, where the osteoprotegerin level correlated with the levels of parasitemia and the malaria clinical score. There were no changes in measures of endothelial glycocalyx or microvascular function. Plasma biomarkers of endothelial activation increased in early P. falciparum and P. vivax infection and preceded changes in the endothelial glycocalyx or microvascular function. The more pronounced increase in osteoprotegerin suggests that this biomarker may play a role in disease pathogenesis.
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26
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Kokkonda S, Deng X, White KL, El Mazouni F, White J, Shackleford DM, Katneni K, Chiu FCK, Barker H, McLaren J, Crighton E, Chen G, Angulo-Barturen I, Jimenez-Diaz MB, Ferrer S, Huertas-Valentin L, Martinez-Martinez MS, Lafuente-Monasterio MJ, Chittimalla R, Shahi SP, Wittlin S, Waterson D, Burrows JN, Matthews D, Tomchick D, Rathod PK, Palmer MJ, Charman SA, Phillips MA. Lead Optimization of a Pyrrole-Based Dihydroorotate Dehydrogenase Inhibitor Series for the Treatment of Malaria. J Med Chem 2020; 63:4929-4956. [PMID: 32248693 DOI: 10.1021/acs.jmedchem.0c00311] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Malaria puts at risk nearly half the world's population and causes high mortality in sub-Saharan Africa, while drug resistance threatens current therapies. The pyrimidine biosynthetic enzyme dihydroorotate dehydrogenase (DHODH) is a validated target for malaria treatment based on our finding that triazolopyrimidine DSM265 (1) showed efficacy in clinical studies. Herein, we describe optimization of a pyrrole-based series identified using a target-based DHODH screen. Compounds with nanomolar potency versus Plasmodium DHODH and Plasmodium parasites were identified with good pharmacological properties. X-ray studies showed that the pyrroles bind an alternative enzyme conformation from 1 leading to improved species selectivity versus mammalian enzymes and equivalent activity on Plasmodium falciparum and Plasmodium vivax DHODH. The best lead DSM502 (37) showed in vivo efficacy at similar levels of blood exposure to 1, although metabolic stability was reduced. Overall, the pyrrole-based DHODH inhibitors provide an attractive alternative scaffold for the development of new antimalarial compounds.
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Affiliation(s)
- Sreekanth Kokkonda
- Departments of Chemistry and Global Health, University of Washington, Seattle, Washington 98195, United States
| | - Xiaoyi Deng
- Departments of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, Texas 75390-9135, United States
| | - Karen L White
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Farah El Mazouni
- Departments of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, Texas 75390-9135, United States
| | - John White
- Departments of Chemistry and Global Health, University of Washington, Seattle, Washington 98195, United States
| | - David M Shackleford
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Kasiram Katneni
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Francis C K Chiu
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Helena Barker
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Jenna McLaren
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Elly Crighton
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Gong Chen
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | | | | | - Santiago Ferrer
- GSK, Tres Cantos Medicines Development Campus, Severo Ochoa, Madrid 28760, Spain
| | | | | | | | | | | | - Sergio Wittlin
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland.,University of Basel, 4002 Basel, Switzerland
| | | | | | - Dave Matthews
- Medicines for Malaria Venture, 1215 Geneva, Switzerland
| | - Diana Tomchick
- Department of Biophysics, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, Texas 75390-9135, United States
| | - Pradipsinh K Rathod
- Departments of Chemistry and Global Health, University of Washington, Seattle, Washington 98195, United States
| | | | - Susan A Charman
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Margaret A Phillips
- Departments of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, Texas 75390-9135, United States
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27
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A Single-Dose Combination Study with the Experimental Antimalarials Artefenomel and DSM265 To Determine Safety and Antimalarial Activity against Blood-Stage Plasmodium falciparum in Healthy Volunteers. Antimicrob Agents Chemother 2019; 64:AAC.01371-19. [PMID: 31685476 PMCID: PMC7187626 DOI: 10.1128/aac.01371-19] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 11/01/2019] [Indexed: 12/12/2022] Open
Abstract
Artefenomel and DSM265 are two new compounds that have been shown to be well tolerated and effective when administered as monotherapy malaria treatment. This study aimed to determine the safety, pharmacokinetics, and pharmacodynamics of artefenomel and DSM265 administered in combination to healthy subjects in a volunteer infection study using the Plasmodium falciparum-induced blood-stage malaria model. Thirteen subjects were inoculated with parasite-infected erythrocytes on day 0 and received a single oral dose of artefenomel and DSM265 on day 7. Cohort 1 (n = 8) received 200 mg artefenomel plus 100 mg DSM265, and cohort 2 (n = 5) received 200 mg artefenomel plus 50 mg DSM265. Blood samples were collected to measure parasitemia, gametocytemia, and artefenomel-DSM265 plasma concentrations. There were no treatment-related adverse events. The pharmacokinetic profiles of artefenomel and DSM265 were similar to those of the compounds when administered as monotherapy, suggesting no pharmacokinetic interactions. A reduction in parasitemia occurred in all subjects following treatment (log10 parasite reduction ratios over 48 h [PRR48] of 2.80 for cohort 1 and 2.71 for cohort 2; parasite clearance half-lives of 5.17 h for cohort 1 and 5.33 h for cohort 2). Recrudescence occurred in 5/8 subjects in cohort 1 between days 19 and 28 and in 5/5 subjects in cohort 2 between days 15 and 22. Low-level gametocytemia (1 to 330 female gametocytes/ml) was detected in all subjects from day 14. The results of this single-dosing combination study support the further clinical development of the use of artefenomel and DSM265 in combination as a treatment for falciparum malaria. (This study has been registered at ClinicalTrials.gov under identifier NCT02389348.).
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28
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Same same, but different: Uncovering unique features of the mitochondrial respiratory chain of apicomplexans. Mol Biochem Parasitol 2019; 232:111204. [DOI: 10.1016/j.molbiopara.2019.111204] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 07/19/2019] [Accepted: 08/01/2019] [Indexed: 01/08/2023]
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29
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Ashton TD, Devine SM, Möhrle JJ, Laleu B, Burrows JN, Charman SA, Creek DJ, Sleebs BE. The Development Process for Discovery and Clinical Advancement of Modern Antimalarials. J Med Chem 2019; 62:10526-10562. [DOI: 10.1021/acs.jmedchem.9b00761] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Trent D. Ashton
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Shane M. Devine
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Jörg J. Möhrle
- Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, 1215 Geneva, Switzerland
| | - Benoît Laleu
- Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, 1215 Geneva, Switzerland
| | - Jeremy N. Burrows
- Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, 1215 Geneva, Switzerland
| | - Susan A. Charman
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Darren J. Creek
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Brad E. Sleebs
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria 3052, Australia
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