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Terman SW, Kirkpatrick L, Kerr WT, Akiyama LF, Baajour W, Atilgan D, Dorotan MKC, Choi HW, French JA. Challenges and directions in epilepsy diagnostics and therapeutics: Proceedings of the 17th Epilepsy Therapies and Diagnostics Development conference. Epilepsia 2024; 65:846-860. [PMID: 38135921 PMCID: PMC11018495 DOI: 10.1111/epi.17875] [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: 11/10/2023] [Revised: 12/19/2023] [Accepted: 12/20/2023] [Indexed: 12/24/2023]
Abstract
Substantial efforts are underway toward optimizing the diagnosis, monitoring, and treatment of seizures and epilepsy. We describe preclinical programs in place for screening investigational therapeutic candidates in animal models, with particular attention to identifying and eliminating drugs that might paradoxically aggravate seizure burden. After preclinical development, we discuss challenges and solutions in the design and regulatory logistics of clinical trial execution, and efforts to develop disease biomarkers and interventions that may be not only seizure-suppressing, but also disease-modifying. As disease-modifying treatments are designed, there is clear recognition that, although seizures represent one critical therapeutic target, targeting nonseizure outcomes like cognitive development or functional outcomes requires changes to traditional designs. This reflects our increasing understanding that epilepsy is a disease with profound impact on quality of life for the patient and caregivers due to both seizures themselves and other nonseizure factors. This review examines selected key challenges and future directions in epilepsy diagnostics and therapeutics, from drug discovery to translational application.
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Affiliation(s)
- Samuel W Terman
- University of Michigan Department of Neurology, Ann Arbor, MI 48109, USA
| | - Laura Kirkpatrick
- University of Pittsburgh Department of Neurology, Pittsburgh, PA 15213, USA
- University of Pittsburgh Department of Pediatrics, Pittsburgh, PA 15213, USA
| | - Wesley T Kerr
- University of Michigan Department of Neurology, Ann Arbor, MI 48109, USA
- University of Pittsburgh Department of Neurology, Pittsburgh, PA 15213, USA
- University of Pittsburgh Department of Biomedical Informatics, Pittsburgh, PA 15213, USA
| | - Lisa F Akiyama
- University of Washington Department of Neurology, Seattle, WA 98105, USA
| | - Wadih Baajour
- University of Texas Health Science Center at Houston, Department of Neurology, Houston, TX 77030, USA
| | - Deniz Atilgan
- University of Texas Health Science Center at Houston, Department of Neurology, Houston, TX 77030, USA
| | | | - Hyoung Won Choi
- Emory University Department of Pediatrics, Division of Neurology, Atlanta, GA 30322
| | - Jacqueline A French
- NYU Grossman School of Medicine and NYU Langone Health, New York, NY 10016, USA
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Bacq A, Depaulis A, Castagné V, Le Guern ME, Wirrell EC, Verleye M. An Update on Stiripentol Mechanisms of Action: A Narrative Review. Adv Ther 2024; 41:1351-1371. [PMID: 38443647 PMCID: PMC10960919 DOI: 10.1007/s12325-024-02813-0] [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: 01/09/2024] [Accepted: 02/02/2024] [Indexed: 03/07/2024]
Abstract
Stiripentol (Diacomit®) (STP) is an orally active antiseizure medication (ASM) indicated as adjunctive therapy, for the treatment of seizures associated with Dravet syndrome (DS), a severe form of childhood epilepsy, in conjunction with clobazam and, in some regions valproic acid. Since the discovery of STP, several mechanisms of action (MoA) have been described that may explain its specific effect on seizures associated with DS. STP is mainly considered as a potentiator of gamma-aminobutyric acid (GABA) neurotransmission: (i) via uptake blockade, (ii) inhibition of degradation, but also (iii) as a positive allosteric modulator of GABAA receptors, especially those containing α3 and δ subunits. Blockade of voltage-gated sodium and T-type calcium channels, which is classically associated with anticonvulsant and neuroprotective properties, has also been demonstrated for STP. Finally, several studies indicate that STP could regulate glucose energy metabolism and inhibit lactate dehydrogenase. STP is also an inhibitor of several cytochrome P450 enzymes involved in the metabolism of other ASMs, contributing to boost their anticonvulsant efficacy as add-on therapy. These different MoAs involved in treatment of DS and recent data suggest a potential for STP to treat other neurological or non-neurological diseases.
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Affiliation(s)
- Alexandre Bacq
- Biocodex Research and Development Center, Compiègne, France.
| | - Antoine Depaulis
- Univ. Grenoble Alpes, Inserm, U1216, Grenoble Institut Neurosciences, Grenoble, France
| | | | | | - Elaine C Wirrell
- Divisions of Child and Adolescent Neurology and Epilepsy, Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Marc Verleye
- Biocodex Research and Development Center, Compiègne, France
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MacLean A, Chappell AS, Kranzler J, Evrard A, Monchal H, Roucard C. BAER-101, a selective potentiator of α2- and α3-containing GABA A receptors, fully suppresses spontaneous cortical spike-wave discharges in Genetic Absence Epilepsy Rats from Strasbourg (GAERS). Drug Dev Res 2024; 85:e22160. [PMID: 38380694 DOI: 10.1002/ddr.22160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 01/29/2024] [Accepted: 01/31/2024] [Indexed: 02/22/2024]
Abstract
BAER-101 (formerly AZD7325) is a selective partial potentiator of α2/3-containing γ-amino-butyric acid A receptors (GABAARs) and produces minimal sedation and dizziness. Antiseizure effects in models of Dravet and Fragile X Syndromes have been published. BAER-101 has been administered to over 700 healthy human volunteers and patients where it was found to be safe and well tolerated. To test the extent of the antiseizure activity of BAER-1010, we tested BAER-101 in the Genetic Absence Epilepsy Rats from Strasbourg (GAERS) model, a widely used and translationally relevant model. GAERS rats with recording electrodes bilaterally located over the frontal and parietal cortices were used. Electroencepholographic (EEG) signals in freely moving awake rats were analyzed for spike-wave discharges (SWDs). BAER-101 was administered orally at doses of 0.3-100 mg/kg and diazepam was used as a positive control using a cross-over protocol with a wash-out period between treatments. The number of SWDs was dose-dependently reduced by BAER-101 with 0.3 mg/kg being the minimally effective dose (MED). The duration of and total time in SWDs were also reduced by BAER-101. Concentrations of drug in plasma achieved an MED of 10.1 nM, exceeding the Ki for α2 or α3, but 23 times lower than the Ki for α5-GABAARs. No adverse events were observed up to a dose 300× MED. The data support the possibility of antiseizure efficacy without the side effects associated with other GABAAR subtypes. This is the first report of an α2/3-selective GABA PAM suppressing seizures in the GAERS model. The data encourage proceeding to test BAER-101 in patients with epilepsy.
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Perucca E, White HS, Bialer M. New GABA-Targeting Therapies for the Treatment of Seizures and Epilepsy: II. Treatments in Clinical Development. CNS Drugs 2023; 37:781-795. [PMID: 37603261 PMCID: PMC10501930 DOI: 10.1007/s40263-023-01025-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/29/2023] [Indexed: 08/22/2023]
Abstract
The inhibitory neurotransmitter γ-aminobutyric acid (GABA) plays an important role in the modulation of neuronal excitability, and a disruption of GABAergic transmission contributes to the pathogenesis of some seizure disorders. Although many currently available antiseizure medications do act at least in part by potentiating GABAergic transmission, there is an opportunity for further research aimed at developing more innovative GABA-targeting therapies. The present article summarises available evidence on a number of such treatments in clinical development. These can be broadly divided into three groups. The first group consists of positive allosteric modulators of GABAA receptors and includes Staccato® alprazolam (an already marketed benzodiazepine being repurposed in epilepsy as a potential rescue inhalation treatment for prolonged and repetitive seizures), the α2/3/5 subtype-selective agents darigabat and ENX-101, and the orally active neurosteroids ETX155 and LPCN 2101. A second group comprises two drugs already marketed for non-neurological indications, which could be repurposed as treatments for seizure disorders. These include bumetanide, a diuretic agent that has undergone clinical trials in phenobarbital-resistant neonatal seizures and for which the rationale for further development in this indication is under debate, and ivermectin, an antiparasitic drug currently investigated in a randomised double-blind trial in focal epilepsy. The last group comprises a series of highly innovative therapies, namely GABAergic interneurons (NRTX-001) delivered via stereotactic cerebral implantation as a treatment for mesial temporal lobe epilepsy, an antisense oligonucleotide (STK-001) aimed at upregulating NaV1.1 currents and restoring the function of GABAergic interneurons, currently tested in a trial in patients with Dravet syndrome, and an adenoviral vector-based gene therapy (ETX-101) scheduled for investigation in Dravet syndrome. Another agent, a subcutaneously administered neuroactive peptide (NRP2945) that reportedly upregulates the expression of GABAA receptor α and β subunits is being investigated, with Lennox-Gastaut syndrome and other epilepsies as proposed indications. The diversity of the current pipeline underscores a strong interest in the GABA system as a target for new treatment development in epilepsy. To date, limited clinical data are available for these investigational treatments and further studies are required to assess their potential value in addressing unmet needs in epilepsy management.
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Affiliation(s)
- Emilio Perucca
- Department of Medicine (Austin Health), Melbourne Brain Centre, The University of Melbourne, 245 Burgundy Street, Melbourne, VIC, 3084, Australia.
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia.
| | - H Steve White
- Department of Pharmacy, School of Pharmacy, University of Washington, Seattle, WA, USA
| | - Meir Bialer
- Faculty of Medicine, Institute of Drug Research, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem, Israel
- David R. Bloom Center for Pharmacy, The Hebrew University of Jerusalem, Jerusalem, Israel
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King H, Reiber M, Philippi V, Stirling H, Aulehner K, Bankstahl M, Bleich A, Buchecker V, Glasenapp A, Jirkof P, Miljanovic N, Schönhoff K, von Schumann L, Leenaars C, Potschka H. Anesthesia and analgesia for experimental craniotomy in mice and rats: a systematic scoping review comparing the years 2009 and 2019. Front Neurosci 2023; 17:1143109. [PMID: 37207181 PMCID: PMC10188949 DOI: 10.3389/fnins.2023.1143109] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/27/2023] [Indexed: 05/21/2023] Open
Abstract
Experimental craniotomies are a common surgical procedure in neuroscience. Because inadequate analgesia appears to be a problem in animal-based research, we conducted this review and collected information on management of craniotomy-associated pain in laboratory mice and rats. A comprehensive search and screening resulted in the identification of 2235 studies, published in 2009 and 2019, describing craniotomy in mice and/or rats. While key features were extracted from all studies, detailed information was extracted from a random subset of 100 studies/year. Reporting of perioperative analgesia increased from 2009 to 2019. However, the majority of studies from both years did not report pharmacologic pain management. Moreover, reporting of multimodal treatments remained at a low level, and monotherapeutic approaches were more common. Among drug groups, reporting of pre- and postoperative administration of non-steroidal anti-inflammatory drugs, opioids, and local anesthetics in 2019 exceeded that of 2009. In summary, these results suggest that inadequate analgesia and oligoanalgesia are persistent issues associated with experimental intracranial surgery. This underscores the need for intensified training of those working with laboratory rodents subjected to craniotomies. Systematic review registration https://osf.io/7d4qe.
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Affiliation(s)
- Hannah King
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Maria Reiber
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Vanessa Philippi
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Helen Stirling
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Katharina Aulehner
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Marion Bankstahl
- Hannover Medical School, Institute for Laboratory Animal Science, Hanover, Germany
| | - André Bleich
- Hannover Medical School, Institute for Laboratory Animal Science, Hanover, Germany
| | - Verena Buchecker
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Aylina Glasenapp
- Hannover Medical School, Institute for Laboratory Animal Science, Hanover, Germany
| | - Paulin Jirkof
- Office for Animal Welfare and 3Rs, University of Zurich, Zurich, Switzerland
| | - Nina Miljanovic
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Katharina Schönhoff
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Lara von Schumann
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Cathalijn Leenaars
- Hannover Medical School, Institute for Laboratory Animal Science, Hanover, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
- *Correspondence: Heidrun Potschka,
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Gurrell R, Iredale P, Evrard A, Duveau V, Ruggiero C, Roucard C. Pronounced antiseizure activity of the subtype-selective GABA A positive allosteric modulator darigabat in a mouse model of drug-resistant focal epilepsy. CNS Neurosci Ther 2022; 28:1875-1882. [PMID: 35965432 PMCID: PMC9532903 DOI: 10.1111/cns.13927] [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: 05/23/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 11/28/2022] Open
Abstract
Aim Darigabat is an α2/3/5 subunit‐selective positive allosteric modulator of GABAA receptors that has demonstrated broad‐spectrum activity in several preclinical models of epilepsy as well as in a clinical photoepilepsy trial. The objective here was to assess the acute antiseizure effect of darigabat in the mesial temporal lobe epilepsy (MTLE) mouse model of drug‐resistant focal seizures. Methods The MTLE model is generated by single unilateral intrahippocampal injection of low dose (1 nmole) kainic acid in adult mice, and subsequent epileptiform activity is recorded following implantation of a bipolar electrode under general anesthesia. After a period of epileptogenesis (~4 weeks), spontaneous and recurrent hippocampal paroxysmal discharges (HPD; focal seizures) are recorded using intracerebral electroencephalography. The number and cumulated duration of HPDs were recorded following administration of vehicle (PO), darigabat (0.3–10 mg kg−1, PO), and positive control diazepam (2 mg kg−1, IP). RESULTS Darigabat dose‐dependently reduced the expression of HPDs, demonstrating comparable efficacy profile to diazepam at doses of 3 and 10 mg kg−1. CONCLUSIONS Darigabat exhibited a robust efficacy profile in the MTLE model, a preclinical model of drug‐resistant focal epilepsy. A Phase II proof‐of‐concept placebo‐controlled, adjunctive‐therapy trial (NCT04244175) is ongoing to evaluate efficacy and safety of darigabat in patients with drug‐resistant focal seizures.
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Cerne R, Lippa A, Poe MM, Smith JL, Jin X, Ping X, Golani LK, Cook JM, Witkin JM. GABAkines - Advances in the discovery, development, and commercialization of positive allosteric modulators of GABA A receptors. Pharmacol Ther 2022; 234:108035. [PMID: 34793859 PMCID: PMC9787737 DOI: 10.1016/j.pharmthera.2021.108035] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 11/08/2021] [Indexed: 12/25/2022]
Abstract
Positive allosteric modulators of γ-aminobutyric acid-A (GABAA) receptors or GABAkines have been widely used medicines for over 70 years for anxiety, epilepsy, sleep, and other disorders. Traditional GABAkines like diazepam have safety and tolerability concerns that include sedation, motor-impairment, respiratory depression, tolerance and dependence. Multiple GABAkines have entered clinical development but the issue of side-effects has not been fully solved. The compounds that are presently being developed and commercialized include several neuroactive steroids (an allopregnanolone formulation (brexanolone), an allopregnanolone prodrug (LYT-300), Sage-324, zuranolone, and ganaxolone), the α2/3-preferring GABAkine, KRM-II-81, and the α2/3/5-preferring GABAkine PF-06372865 (darigabat). The neuroactive steroids are in clinical development for post-partum depression, intractable epilepsy, tremor, status epilepticus, and genetic epilepsy disorders. Darigabat is in development for epilepsy and anxiety. The imidazodiazepine, KRM-II-81 is efficacious in animal models for the treatment of epilepsy and post-traumatic epilepsy, acute and chronic pain, as well as anxiety and depression. The efficacy of KRM-II-81 in models of pharmacoresistant epilepsy, preventing the development of seizure sensitization, and in brain tissue of intractable epileptic patients bodes well for improved therapeutics. Medicinal chemistry efforts are also ongoing to identify novel and improved GABAkines. The data document gaps in our understanding of the molecular pharmacology of GABAkines that drive differential pharmacological profiles, but emphasize advancements in the ability to successfully utilize GABAA receptor potentiation for therapeutic gain in neurology and psychiatry.
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Affiliation(s)
- Rok Cerne
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN USA,Faculty of Medicine, University of Ljubljana, Zaloška cesta 4, Ljubljana, Slovenia.,RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA,Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Arnold Lippa
- RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA
| | | | - Jodi L. Smith
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN USA
| | - Xiaoming Jin
- Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Xingjie Ping
- Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Lalit K. Golani
- Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - James M. Cook
- RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA,Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Jeffrey M. Witkin
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN USA,RespireRx Pharmaceuticals Inc, Glen Rock, NJ, USA,Department of Chemistry and Biochemistry, Milwaukee Institute of Drug Discovery, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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Pong AW, Ross J, Tyrlikova I, Giermek AJ, Kohli MP, Khan YA, Salgado RD, Klein P. Epilepsy: Expert opinion on emerging drugs in phase 2/3 clinical trials. Expert Opin Emerg Drugs 2022; 27:75-90. [PMID: 35341431 DOI: 10.1080/14728214.2022.2059464] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Despite the existence of over 30 anti-seizure medications (ASM), including 20 over the last 30 years, a third of patients with epilepsy remain refractory to treatment, with no disease-modifying or preventive therapies until very recently. The development of new ASMs with new mechanisms of action is therefore critical. Recent clinical trials of new treatments have shifted focus from the traditional common epilepsies to rare, genetic epilepsies with known mechanistic targets for treatment and disease-specific animal models. AREAS COVERED ASMs in phase 2a/b and 3 clinical trials target cholesterol, serotonin, sigma-1 receptors, potassium channels and metabotrobic glutamate receptors. Neuroinflammation, protein misfolding, abnormal thalamocortical firing, and molecular deficiencies are among the targeted pathways. Clinically, the current phase 2a/b-3 agents hold promise for variety of epilepsy conditions, from developmental epileptic encephalopathies (Dravet Syndrome, Lennox-Gastaut syndrome, CDKL5 and PCDH19, Rett's Syndrome), Infantile Spasms, Tuberous Sclerosis as well as focal and idiopathic generalized epilepsies and acute rescue therapy for cluster seizures. EXPERT OPINION New delivery mechanisms increase potency and site-specificity of existing drugs. Novel mechanisms of action involve cholesterol degradation, mitochondrial pathways, anti-inflammation and neuro-regeneration. Earlier identification of genetic conditions through genetic testing will allow for earlier use of disease specific and disease-modifying therapies.
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Affiliation(s)
- Amanda W Pong
- Comprehensive Neurology Clinics of Bethesda, Mid-Atlantic Epilepsy and Sleep Center,Bethesda, MD, USA
| | - Jonathan Ross
- Comprehensive Neurology Clinics of Bethesda, Mid-Atlantic Epilepsy and Sleep Center,Bethesda, MD, USA
| | - Ivana Tyrlikova
- Comprehensive Neurology Clinics of Bethesda, Mid-Atlantic Epilepsy and Sleep Center,Bethesda, MD, USA
| | - Alexander J Giermek
- Comprehensive Neurology Clinics of Bethesda, Mid-Atlantic Epilepsy and Sleep Center,Bethesda, MD, USA
| | - Maya P Kohli
- Comprehensive Neurology Clinics of Bethesda, Mid-Atlantic Epilepsy and Sleep Center,Bethesda, MD, USA
| | - Yousef A Khan
- Comprehensive Neurology Clinics of Bethesda, Mid-Atlantic Epilepsy and Sleep Center,Bethesda, MD, USA
| | - Roger D Salgado
- Comprehensive Neurology Clinics of Bethesda, Mid-Atlantic Epilepsy and Sleep Center,Bethesda, MD, USA
| | - Pavel Klein
- Comprehensive Neurology Clinics of Bethesda, Mid-Atlantic Epilepsy and Sleep Center,Bethesda, MD, USA
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Riban V, Heulard I, Reversat L, Si Hocine H, Verleye M. Stiripentol inhibits spike‐and‐waves discharges in animal models of absence seizures, a new mechanism of action involving T‐type calcium channels? Epilepsia 2022; 63:1200-1210. [PMID: 35184274 PMCID: PMC9314114 DOI: 10.1111/epi.17201] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 02/13/2022] [Accepted: 02/15/2022] [Indexed: 11/29/2022]
Abstract
Objective Stiripentol (STP; Diacomit®) is an antiepileptic drug indicated for Dravet syndrome that has been identified as a γ‐aminobutyric acid (GABAergic) positive allosteric modulator. Dravet syndrome is characterized by multiple seizure types: generalized tonic–clonic, focal, myoclonic, and absence seizures. In addition to its antiepileptic effects on tonic–clonic seizures, STP has also been reported to reduce the frequency of atypical absence seizures in patients. Our study focused on STP potential effects on absence seizures, to better characterize its full spectrum of mechanisms of action. Methods STP effects on absence seizures were quantified by electroencephalographic recording in two animal models: rats treated with a low dose of pentylenetetrazol (20 mg/kg ip) and rats from the WAG/Rij strain. In addition, we characterized STP effects on T‐type calcium channel activity. Peak currents were recorded with manual patch clamp on cells transfected with cDNA encoding for the human isoform for Cav3.1, Cav3.2, and Cav3.3. Results STP administered before pentylenetetrazol almost completely abolished the generation of spike‐and‐wave discharges (SWDs) at the dose of 300 mg/kg. At this dose, STP also statistically significantly decreased SWD cumulated duration and number in WAG/Rij rats. Its antiepileptic effect was maintained in WAG/Rij rats, whose seizures were aggravated by the GABA agonist THIP (gaboxadol hydrochloride). Furthermore, electrophysiological recordings showed that STP inhibits T‐type calcium channel peak activity, with a higher specificity for the Cav3.3 subtype. Significance In addition to its previously characterized anticonvulsive properties, these data highlight a new mechanism of action of STP on abnormal thalamocortical activity. This strong antiabsence effect on seizures is correlated with an inhibition of T‐type calcium channels. This new mechanism of action could be implicated in the specificity of STP therapeutic effects in Dravet syndrome.
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Affiliation(s)
- Veronique Riban
- Pharmacology department Biocodex Chemin d’Armancourt 60200 Compiegne France
| | - Isabelle Heulard
- Pharmacology department Biocodex Chemin d’Armancourt 60200 Compiegne France
| | - Lucie Reversat
- Pharmacology department Biocodex Chemin d’Armancourt 60200 Compiegne France
| | | | - Marc Verleye
- Pharmacology department Biocodex Chemin d’Armancourt 60200 Compiegne France
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The imidazodiazepine, KRM-II-81: An example of a newly emerging generation of GABAkines for neurological and psychiatric disorders. Pharmacol Biochem Behav 2022; 213:173321. [PMID: 35041859 DOI: 10.1016/j.pbb.2021.173321] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/21/2021] [Accepted: 12/30/2021] [Indexed: 02/07/2023]
Abstract
GABAkines, or positive allosteric modulators of γ-aminobutyric acid-A (GABAA) receptors, are used for the treatment of anxiety, epilepsy, sleep, and other disorders. The search for improved GABAkines, with reduced safety liabilities (e.g., dependence) or side-effect profiles (e.g., sedation) constituted multiple discovery and development campaigns that involved a multitude of strategies over the past century. Due to the general lack of success in the development of new GABAkines, there had been a decades-long draught in bringing new GABAkines to market. Recently, however, there has been a resurgence of efforts to bring GABAkines to patients, the FDA approval of the neuroactive steroid brexanolone for post-partum depression in 2019 being the first. Other neuroactive steroids are in various stages of clinical development (ganaxolone, zuranolone, LYT-300, Sage-324, PRAX 114, and ETX-155). These GABAkines and non-steroid compounds (GRX-917, a TSPO binding site ligand), darigabat (CVL-865), an α2/3/5-preferring GABAkine, SAN711, an α3-preferring GABAkine, and the α2/3-preferring GABAkine, KRM-II-81, bring new therapeutic promise to this highly utilized medicinal target in neurology and psychiatry. Herein, we also discuss possible conditions that have enabled the transition to a new age of GABAkines. We highlight the pharmacology of KRM-II-81 that has the most preclinical data reported. KRM-II-81 is the lead compound in a new series of orally bioavailable imidazodiazepines entering IND-enabling safety studies. KRM-II-81 has a preclinical profile predicting efficacy against pharmacoresistant epilepsies, traumatic brain injury, and neuropathic pain. KRM-II-81 also produces anxiolytic- and antidepressant-like effects in rodent models. Other key features of the pharmacology of this compound are its low sedation rate, lack of tolerance development, and the ability to prevent the development of seizure sensitization.
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Roebuck AJ, Greba Q, Smolyakova AM, Alaverdashvili M, Marks WN, Garai S, Baglot SL, Petrie G, Cain SM, Snutch TP, Thakur GA, Hill MN, Howland JG, Laprairie RB. Positive allosteric modulation of type 1 cannabinoid receptors reduces spike-and-wave discharges in Genetic Absence Epilepsy Rats from Strasbourg. Neuropharmacology 2021; 190:108553. [PMID: 33845076 DOI: 10.1016/j.neuropharm.2021.108553] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/25/2021] [Accepted: 03/30/2021] [Indexed: 01/30/2023]
Abstract
Childhood Absence Epilepsy (CAE) accounts for approximately 10% of all pediatric epilepsies. Current treatments for CAE are ineffective in approximately 1/3 of patients and can be associated with severe side effects such as hepatotoxicity. Certain cannabinoids, such as cannabidiol (CBD), have shown promise in the treatment of pediatric epilepsies. However, CBD remains limited or prohibited in many jurisdictions, and has not been shown to have efficacy in CAE. Modulation of the type 1 cannabinoid receptor (CB1R) may provide more desirable pharmacological treatments. Genetic Absence Epilepsy Rats from Strasbourg (GAERS) model many aspects of CAE, including cortical spike and wave discharges (SWDs). We have recently demonstrated that Δ9-tetrahydrocannabinol (THC) increases SWDs in GAERS whereas CBD decreases these events. Here, we characterized aspects of the endocannabinoid system in brain areas relevant to seizures in GAERS and tested whether positive allosteric modulators (PAMs) of CB1R reduced SWDs. Both female and male GAERS had reduced (>50%) expression of CB1R and elevated levels of the endocannabinoid 2-AG in cortex compared to non-epileptic controls (NEC). We then administered the CB1R PAMs GAT211 and GAT229 to GAERS implanted with cortical electrodes. Systemic administration of GAT211 to male GAERS reduced SWDs by 40%. Systemic GAT229 administration reduced SWDs in female and male GAERS. Intracerebral infusion of GAT229 into the cortex of male GAERS reduced SWDs by >60% in a CB1R-dependent manner that was blocked by SR141716A. Together, these experiments identify altered endocannabinoid tone in GAERS and suggest that CB1R PAMs should be explored for treatment of absence seizures.
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Affiliation(s)
- Andrew J Roebuck
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada; School of Liberal Arts, Yukon University, Whitehorse, YT, Y1A 5K4, Canada
| | - Quentin Greba
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada
| | - Anna-Maria Smolyakova
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK, S7N 2Z4, Canada
| | - Mariam Alaverdashvili
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK, S7N 2Z4, Canada
| | - Wendie N Marks
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada
| | - Sumanta Garai
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, United States
| | - Samantha L Baglot
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Gavin Petrie
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Stuart M Cain
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Terrance P Snutch
- Michael Smith Laboratories and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Ganesh A Thakur
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, 02115, United States
| | - Matthew N Hill
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - John G Howland
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada.
| | - Robert B Laprairie
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK, S7N 2Z4, Canada; Department of Pharmacology, College of Medicine, Dalhousie University, Halifax, NS, Canada, B3H 4R2.
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12
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Janković SM, Dješević M, Janković SV. Experimental GABA A Receptor Agonists and Allosteric Modulators for the Treatment of Focal Epilepsy. J Exp Pharmacol 2021; 13:235-244. [PMID: 33727865 PMCID: PMC7954424 DOI: 10.2147/jep.s242964] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/23/2021] [Indexed: 12/16/2022] Open
Abstract
GABA A receptors are ubiquitous in the central nervous system and there is a huge diversity of receptor subtypes in almost all regions of the brain. However, the expression of GABA A receptor subtypes is altered in both the gray and white matter of patients with focal epilepsy. Although there is a number of anticonvulsants with marketing authorization for the treatment of focal epilepsy which act through GABA A receptors, potentiating the inhibitory effects of GABA, it is necessary to develop more potent and more specific GABAergic anticonvulsants that are effective in drug-resistant patients with focal epilepsy. There are three orthosteric and at least seven allosteric agonist binding sites at the GABA A receptor. In experimental and clinical studies, full agonists of GABA A receptors showed a tendency to cause desensitization of the receptors, tolerance, and physical dependence; therefore, partial orthosteric agonists and positive allosteric modulators of GABA A receptors were further developed. Preclinical studies demonstrated the anticonvulsant efficacy of positive allosteric modulators with selective action on GABA A receptors with α2/α3 subunits, but only a handful of them were further tested in clinical trials. The best results were obtained for clobazam (already marketed), ganaxolone (in phase III trials), CVL-865 (in phase II trials), and padsevonil (in phase III trials). Several compounds with more selective action on GABA A receptors, perhaps only in certain brain regions, have the potential to become effective drugs against specific subtypes of focal-onset epilepsy. However, their development needs time, and in the near future we can expect only one or two new GABA A agonists to obtain marketing authorization for focal epilepsy, an advance that would be of use for just a fraction of patients with drug-resistant epilepsy.
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Affiliation(s)
| | - Miralem Dješević
- Cardiology Department, Private Policlinic Center Eurofarm, Sarajevo, Bosnia and Hercegovina
| | - Snežana V Janković
- Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia
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Gurrell R, Whitlock M, Wei H, Shen Z, Ogden A. Safety, Tolerability, and Pharmacokinetics of Multiple Repeated Oral Doses of the α2/3/5-Subtype Selective GABA A -Positive Allosteric Modulator PF-06372865 in Healthy Volunteers. Clin Pharmacol Drug Dev 2021; 10:756-764. [PMID: 33465277 PMCID: PMC8359322 DOI: 10.1002/cpdd.912] [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: 09/02/2020] [Accepted: 12/21/2020] [Indexed: 01/26/2023]
Abstract
Multiple‐dose pharmacokinetics (PK) and safety were investigated in this phase 1 study of PF‐06372865, a positive allosteric modulator of α2/3/5 subunit‐containing γ‐aminobutyric acid A receptors (NCT03351751). In 2 cohorts (7‐8 PF‐06372865 and 2 placebo in each cohort), healthy adult subjects received twice‐daily oral doses of PF‐06372865 for 21 days, which included titration in the first 7 days, followed by a maintenance dose of 25 mg twice daily (Cohort 1) and 42.5 mg twice daily (Cohort 2) for 14 days. Serial PK samples were collected on days 1 and 21. Nineteen subjects were assigned to study treatments; 18 completed the study. Approximate dose‐proportional increases in maximum plasma concentratin and area under the plasma concentration–time curve over the dosing interval were observed. PF‐06372865 was rapidly absorbed with a median time to maximum concentration of 1 to 2 hours following both single‐ and multiple‐dose administration. Mean terminal elimination half‐life on day 21 was approximately 11 hours in both cohorts. All adverse events were mild; the most frequently reported was dizziness. After titration, there were no reports of somnolence. There were no clinically significant safety findings, including a lack of withdrawal symptoms on discontinuation of treatment. These results demonstrate that PF‐06372865 is safe and well tolerated at doses estimated to achieve high receptor occupancy (>80%), a profile differentiated from nonselective benzodiazepines.
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Affiliation(s)
| | | | - Hua Wei
- Pfizer Inc., Shanghai, China
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14
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Bialer M, Johannessen SI, Koepp MJ, Levy RH, Perucca E, Perucca P, Tomson T, White HS. Progress report on new antiepileptic drugs: A summary of the Fifteenth Eilat Conference on New Antiepileptic Drugs and Devices (EILAT XV). II. Drugs in more advanced clinical development. Epilepsia 2020; 61:2365-2385. [PMID: 33165915 DOI: 10.1111/epi.16726] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 12/16/2022]
Abstract
The Fifteenth Eilat Conference on New Antiepileptic Drugs and Devices (EILAT XV) was held as a fully virtual conference from July 27 to July 30, 2020 for the sessions on drugs, and on August 3, 2020 for the sessions on devices. A total of 534 delegates from 63 countries attended lectures and interactive discussions, representing a broad range of disciplines from basic science, clinical research, and clinical care. This progress report provides summaries of recent findings on investigational compounds for which preclinical data as well as data from patient studies were presented. The report includes the following five compounds: anakinra, cenobamate, CVL-865, fenfluramine, and ganaxolone, all with novel modes of action compared to more established antiepileptic drugs. Some of these compounds demonstrated promising results in placebo-controlled phase 3 trials, and two have recently received approval from the US Food and Drug Administration (FDA). These include cenobamate, which was approved by the FDA on November 21, 2019 for the treatment of partial onset (focal) seizures in adults, and fenfluramine oral solution, which was approved by the FDA on June 25, 2020 for the treatment of seizures associated with Dravet syndrome in patients 2 years and older.
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Affiliation(s)
- Meir Bialer
- Faculty of Medicine, School of Pharmacy and David R. Bloom Center for Pharmacy, Institute for Drug Research, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Svein I Johannessen
- National Center for Epilepsy, Sandvika, Norway.,Department of Pharmacology, Oslo University Hospital, Oslo, Norway
| | - Matthias J Koepp
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - René H Levy
- Department of Pharmaceutics and Neurological Surgery, University of Washington, Seattle, WA, USA
| | - Emilio Perucca
- Department of Internal Medicine and Therapeutics, University of Pavia, Pavia, Italy.,IRCCS Mondino Foundation, Pavia, Italy
| | - Piero Perucca
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia.,Department of Medicine and Neurology, Royal Melbourne Hospital, University of Melbourne, Melbourne, Victoria, Australia.,Department of Neurology, Alfred Health, Melbourne, Victoria, Australia
| | - Torbjörn Tomson
- Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden
| | - H Steve White
- Department of Pharmacy, School of Pharmacy, University of Washington, Seattle, WA, USA
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15
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Zhu L, Chen L, Xu P, Lu D, Dai S, Zhong L, Han Y, Zhang M, Xiao B, Chang L, Wu Q. Genetic and molecular basis of epilepsy-related cognitive dysfunction. Epilepsy Behav 2020; 104:106848. [PMID: 32028124 DOI: 10.1016/j.yebeh.2019.106848] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 12/06/2019] [Accepted: 12/06/2019] [Indexed: 02/02/2023]
Abstract
Epilepsy is a common neurological disease characterized by recurrent seizures. About 70 million people were affected by epilepsy or epileptic seizures. Epilepsy is a complicated complex or symptomatic syndromes induced by structural, functional, and genetic causes. Meanwhile, several comorbidities are accompanied by epileptic seizures. Cognitive dysfunction is a long-standing complication associated with epileptic seizures, which severely impairs quality of life. Although the definitive pathogenic mechanisms underlying epilepsy-related cognitive dysfunction remain unclear, accumulating evidence indicates that multiple risk factors are probably involved in the development and progression of cognitive dysfunction in patients with epilepsy. These factors include the underlying etiology, recurrent seizures or status epilepticus, structural damage that induced secondary epilepsy, genetic variants, and molecular alterations. In this review, we summarize several theories that may explain the genetic and molecular basis of epilepsy-related cognitive dysfunction.
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Affiliation(s)
- Lin Zhu
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Lu Chen
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Puying Xu
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Di Lu
- Biomedicine Engineering Research Center, Kunming Medical University, 1168 Chun Rong West Road, Kunming, Yunnan 650500, PR China
| | - Shujuan Dai
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Lianmei Zhong
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Yanbing Han
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China
| | - Mengqi Zhang
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiang Ya Road, Changsha, Hunan 410008, PR China
| | - Bo Xiao
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiang Ya Road, Changsha, Hunan 410008, PR China
| | - Lvhua Chang
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China.
| | - Qian Wu
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, 295 Xi Chang Road, Kunming, Yunnan 650032, PR China.
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Amrutkar DV, Dyhring T, Jacobsen TA, Larsen JS, Sandager-Nielsen K. Anti-Tremor Action of Subtype Selective Positive Allosteric Modulators of GABAA Receptors in a Rat Model of Essential Tremors. THE CEREBELLUM 2020; 19:265-274. [DOI: 10.1007/s12311-020-01106-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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17
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Witkin JM, Li G, Golani LK, Xiong W, Smith JL, Ping X, Rashid F, Jahan R, Cerne R, Cook JM, Jin X. The Positive Allosteric Modulator of α2/3-Containing GABA A Receptors, KRM-II-81, Is Active in Pharmaco-Resistant Models of Epilepsy and Reduces Hyperexcitability after Traumatic Brain Injury. J Pharmacol Exp Ther 2020; 372:83-94. [PMID: 31694876 PMCID: PMC6927408 DOI: 10.1124/jpet.119.260968] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Accepted: 10/17/2019] [Indexed: 12/14/2022] Open
Abstract
The imidizodiazepine, 5-(8-ethynyl-6-(pyridin-2-yl)-4H-benzo[f]imidazo[1,5-a][1,4]diazepin-3-yl)oxazole (KRM-II-81), is selective for α2/3-containing GABAA receptors. KRM-II-81 dampens seizure activity in rodent models with enhanced efficacy and reduced motor-impairment compared with diazepam. In the present study, KRM-II-81 was studied in assays designed to detect antiepileptics with improved chances of impacting pharmaco-resistant epilepsies. The potential for reducing neural hyperactivity weeks after traumatic brain injury was also studied. KRM-II-81 suppressed convulsions in corneal-kindled mice. Mice with kainate-induced mesial temporal lobe seizures exhibited spontaneous recurrent hippocampal paroxysmal discharges that were significantly reduced by KRM-II-81 (15 mg/kg, orally). KRM-II-81 also decreased convulsions in rats undergoing amygdala kindling in the presence of lamotrigine (lamotrigine-insensitive model) (ED50 = 19 mg/kg, i.p.). KRM-II-81 reduced focal and generalized seizures in a kainate-induced chronic epilepsy model in rats (20 mg/kg, i.p., three times per day). In mice with damage to the left cerebral cortex by controlled-cortical impact, enduring neuronal hyperactivity was dampened by KRM-II-81 (10 mg/kg, i.p.) as observed through in vivo two-photon imaging of layer II/III pyramidal neurons in GCaMP6-expressing transgenic mice. No notable side effects emerged up to doses of 300 mg/kg KRM-II-81. Molecular modeling studies were conducted: docking in the binding site of the α1β3γ2L GABAA receptor showed that replacing the C8 chlorine atom of alprazolam with the acetylene of KRM-II-81 led to loss of the key interaction with α1His102, providing a structural rationale for its low affinity for α1-containing GABAA receptors compared with benzodiazepines such as alprazolam. Overall, these findings predict that KRM-II-81 has improved therapeutic potential for epilepsy and post-traumatic epilepsy. SIGNIFICANCE STATEMENT: We describe the effects of a relatively new orally bioavailable small molecule in rodent models of pharmaco-resistant epilepsy and traumatic brain injury. KRM-II-81 is more potent and generally more efficacious than standard-of-care antiepileptics. In silico docking experiments begin to describe the structural basis for the relative lack of motor impairment induced by KRM-II-81. KRM-II-81 has unique structural and anticonvulsant effects, predicting its potential as an improved antiepileptic drug and novel therapy for post-traumatic epilepsy.
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Affiliation(s)
- Jeffrey M Witkin
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Guanguan Li
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Lalit K Golani
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Wenhui Xiong
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Jodi L Smith
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Xingjie Ping
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Farjana Rashid
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Rajwana Jahan
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Rok Cerne
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - James M Cook
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
| | - Xiaoming Jin
- Department of Neurologic Surgery, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., R.C., X.J.); Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin (J.M.W., G.L., L.K.G., F.R., R.J., J.M.C.); Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana (W.X., X.P., X.J.); and Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, Indiana (J.L.S.)
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18
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Maramai S, Benchekroun M, Ward SE, Atack JR. Subtype Selective γ-Aminobutyric Acid Type A Receptor (GABAAR) Modulators Acting at the Benzodiazepine Binding Site: An Update. J Med Chem 2019; 63:3425-3446. [DOI: 10.1021/acs.jmedchem.9b01312] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Samuele Maramai
- Sussex Drug Discovery Centre, University of Sussex, Brighton BN1 9QJ, U.K
| | - Mohamed Benchekroun
- Sussex Drug Discovery Centre, University of Sussex, Brighton BN1 9QJ, U.K
- Équipe de Chimie Moléculaire, Laboratoire de Génomique Bioinformatique et Chimie Moléculaire, GBCM, EA7528, Conservatoire National des Arts et Métiers, 2 rue Conté, 75003 Paris, France
| | - Simon E. Ward
- Medicines Discovery Institute, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, U.K
| | - John R. Atack
- Medicines Discovery Institute, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, U.K
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Yu Y, Nguyen DT, Jiang J. G protein-coupled receptors in acquired epilepsy: Druggability and translatability. Prog Neurobiol 2019; 183:101682. [PMID: 31454545 DOI: 10.1016/j.pneurobio.2019.101682] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/09/2019] [Accepted: 08/15/2019] [Indexed: 02/06/2023]
Abstract
As the largest family of membrane proteins in the human genome, G protein-coupled receptors (GPCRs) constitute the targets of more than one-third of all modern medicinal drugs. In the central nervous system (CNS), widely distributed GPCRs in neuronal and nonneuronal cells mediate numerous essential physiological functions via regulating neurotransmission at the synapses. Whereas their abnormalities in expression and activity are involved in various neuropathological processes. CNS conditions thus remain highly represented among the indications of GPCR-targeted agents. Mounting evidence from a large number of animal studies suggests that GPCRs play important roles in the regulation of neuronal excitability associated with epilepsy, a common CNS disease afflicting approximately 1-2% of the population. Surprisingly, none of the US Food and Drug Administration (FDA)-approved (>30) antiepileptic drugs (AEDs) suppresses seizures through acting on GPCRs. This disparity raises concerns about the translatability of these preclinical findings and the druggability of GPCRs for seizure disorders. The currently available AEDs intervene seizures predominantly through targeting ion channels and have considerable limitations, as they often cause unbearable adverse effects, fail to control seizures in over 30% of patients, and merely provide symptomatic relief. Thus, identifying novel molecular targets for epilepsy is highly desired. Herein, we focus on recent progresses in understanding the comprehensive roles of several GPCR families in seizure generation and development of acquired epilepsy. We also dissect current hurdles hindering translational efforts in developing GPCRs as antiepileptic and/or antiepileptogenic targets and discuss the counteracting strategies that might lead to a potential cure for this debilitating CNS condition.
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Affiliation(s)
- Ying Yu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Davis T Nguyen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jianxiong Jiang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Drug Discovery Center, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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Witkin JM, Ping X, Cerne R, Mouser C, Jin X, Hobbs J, Tiruveedhula VVNPB, Li G, Jahan R, Rashid F, Kumar Golani L, Cook JM, Smith JL. The value of human epileptic tissue in the characterization and development of novel antiepileptic drugs: The example of CERC-611 and KRM-II-81. Brain Res 2019; 1722:146356. [PMID: 31369732 DOI: 10.1016/j.brainres.2019.146356] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 07/17/2019] [Accepted: 07/29/2019] [Indexed: 12/25/2022]
Abstract
The need for improved antiepileptics is clearly mandated despite the existence of multiple existing medicines from different chemical and mechanistic classes. Standard of care agents do not fully control epilepsies and have a variety of side-effect and safety issues. Patients typically take multiple antiepileptic drugs and yet many continue to have seizures. Antiepileptic-unresponsive seizures are life-disrupting and life-threatening. One approach to seizure control is surgical resection of affected brain tissue and associated neural circuits. Although non-human brain studies can provide insight into novel antiepileptic mechanisms, human epileptic brain is the bottom-line biological substrate. Human epileptic brain can provide definitive information on the presence or absence of the putative protein targets of interest in the patient population, the potential changes in these proteins in the epileptic state, and the engagement of novel molecules and their functional impact in target tissue. In this review, we discuss data on two novel potential antiepileptic drugs. CERC-611 (LY3130481) is an AMPA receptor antagonist that selectively blocks AMPA receptors associated with the auxiliary protein TARP γ-8 and is in clinical development. KRM-II-81 is a positive allosteric modulator of GABAA receptors selectively associated with protein subunits α2 and α 3. Preclinical data on these compounds argue that patient-based biological data increase the probability that a newly discovered molecule will translate its antiepileptic potential to patients.
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Affiliation(s)
- Jeffrey M Witkin
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA; Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA.
| | - Xingjie Ping
- Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Rok Cerne
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Claire Mouser
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Xiaoming Jin
- Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA
| | - Jon Hobbs
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | | | - Guanguan Li
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Rajwana Jahan
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Farjana Rashid
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Lalit Kumar Golani
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - James M Cook
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Jodi L Smith
- Laboratory of Antiepileptic Drug Discovery, St. Vincent's Hospital, Indianapolis, IN, USA.
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Duveau V, Buhl DL, Evrard A, Ruggiero C, Mandé-Niedergang B, Roucard C, Gurrell R. Pronounced antiepileptic activity of the subtype-selective GABA A -positive allosteric modulator PF-06372865 in the GAERS absence epilepsy model. CNS Neurosci Ther 2018; 25:255-260. [PMID: 30101518 DOI: 10.1111/cns.13046] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 07/05/2018] [Accepted: 07/17/2018] [Indexed: 12/27/2022] Open
Abstract
AIM Antiepileptic drugs that modulate GABA have the potential to aggravate or improve the symptoms of absence epilepsy. PF-06372865 is a positive allosteric modulator (PAM) of α2/3/5 subunit-containing GABAA receptors with minimal activity at α1-containing receptors, which are believed to mediate many of the adverse events associated with benzodiazepines. The aim of this study was to assess the antiepileptic effect of PF-06372865 in a preclinical model of absence seizures. METHODS Genetic absence epilepsy rats from Strasbourg (GAERS) was implanted with four cortical electrodes over the frontoparietal cortex, and the number and cumulated duration of spike-and-wave discharges (SWDs) were recorded for 10-90 minutes following administration of vehicle, PF-06372865, and positive controls diazepam and valproate. RESULTS PF-06372865 (0.3, 1, 2, 10 mg kg-1 ) dose-dependently reduced the expression of SWDs, including full suppression at the highest doses by 30 minutes after administration. CONCLUSIONS PF-06372865 demonstrated robust efficacy in suppressing SWDs in the GAERS model of absence epilepsy. To our knowledge, this is the first demonstration of antiepileptic activity of an α2/3/5-subtype-selective GABAA PAM in a model of absence epilepsy. Further study of the antiepileptic properties of PF-06372865 is warranted in patients with absence seizures.
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Affiliation(s)
| | - Derek L Buhl
- Neuroscience Research Unit, Pfizer Inc, Cambridge, Massachusetts
| | | | | | | | | | - Rachel Gurrell
- Early Clinical Development, Pfizer Inc, Granta Park, Cambridge, UK
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