ucb-34714 and Disease-Models--Animal

Animal-to-man extrapolation and therapeutic dose prediction are illustrated with two molecules designed to treat epilepsy. Synaptic vesicle protein 2A (SV2A) is the primary molecular target for their anticonvulsive effect, but additional mechanisms may also contribute. Brivaracetam (BRV), currently in phase 3 of clinical development, was used as the benchmark compound. A pharmacokinetic/pharmacodynamic model was built in NONMEM, relating the brain tissue concentrations of BRV in mice and the proportion of animals protected against convulsions in the pharmacological model of audiogenic seizures. Brain concentrations were linked with ex vivo binding to predict brain SV2A occupancy. A physiologically based pharmacokinetic model was developed for predicting BRV concentrations in human plasma and brain tissue. Predicted plasma profiles were in good agreement with observations. Predicted human brain concentrations of BRV and the mouse ex vivo binding pharmacokinetic/pharmacodynamic model were used to extrapolate brain SV2A occupancy at the human therapeutic dose. Secondly, for another compound also exhibiting selective affinity for the same target, similar pharmacokinetic/pharmacodynamic models were built from audiogenic seizure mouse data. Various dosing regimens of the new compound were simulated in order to reach the same brain SV2A occupancy as for the reference compound. These estimations support early development. Assumptions and limitations of the approach are discussed.

Topics: Animals; Anticonvulsants; Brain; Disease Models, Animal; Dose-Response Relationship, Drug; Epilepsy; Humans; Logistic Models; Membrane Glycoproteins; Mice; Nerve Tissue Proteins; Pharmacology; Physiology; Predictive Value of Tests; Protein Binding; Pyrrolidinones; Tissue Distribution

Topics: Acetamides; Animals; Anticonvulsants; Carbamates; Disease Models, Animal; Fructose; Humans; Lacosamide; Pyrroles; Pyrrolidinones; Rats; Receptors, AMPA; Status Epilepticus; Tetrahydroisoquinolines; Topiramate; Treatment Outcome

Topics: Acetamides; Amines; Animals; Anticonvulsants; Benzodiazepines; Carbamates; Cyclohexanecarboxylic Acids; Disease Models, Animal; Drug Design; Gabapentin; gamma-Aminobutyric Acid; Humans; Lacosamide; Levetiracetam; Phenylenediamines; Piracetam; Pregabalin; Pregnanolone; Pyrrolidinones; Triazoles

To evaluate acute and long-term effects of intravenous brivaracetam (BRV) and BRV + diazepam (DZP) combination treatment in a rat model of self-sustaining status epilepticus (SSSE).. Rats were treated with BRV (10 mg/kg) 10 min after initiation of perforant path stimulation (PPS) as early treatment; or BRV (10-300 mg/kg), DZP (1 mg/kg), or BRV (0.3-10 mg/kg) + DZP (1 mg/kg) 10 min after the end of PPS (established SSSE). Seizure activity was recorded electrographically for 24 h posttreatment (acute effects), and for 1 week at 6-8 weeks or 12 months' posttreatment (long-term effects). All treatments were compared with control rats using one-way analysis of variance (ANOVA) and Bonferroni's test, or Kruskal--Wallis and Dunn's multiple comparison tests, when appropriate.. Treatment of established SSSE with BRV (10-300 mg/kg) resulted in dose-dependent reduction in SSSE duration and cumulative seizure time, achieving statistical significance at doses ≥100 mg/kg. Lower doses of BRV (0.3-10 mg/kg) + low-dose DZP (1 mg/kg) significantly reduced SSSE duration and number of seizures. All control rats developed spontaneous recurrent seizures (SRS) 6-8 weeks after SSSE, whereas seizure freedom was noted in 2/10, 5/10, and 6/10 rats treated with BRV 200 mg/kg, 300 mg/kg, and BRV 10 mg/kg + DZP, respectively. BRV (10-300 mg/kg) showed a dose-dependent trend toward reduction of SRS frequency, cumulative seizure time, and spike frequency, achieving statistical significance at 300 mg/kg. Combination of BRV (10 mg/kg) + DZP significantly reduced SRS frequency, cumulative seizure time, and spike frequency. In the 12-month follow-up study, BRV (0.3-10 mg/kg) + low-dose DZP markedly reduced SRS frequency, cumulative seizure time, and spike frequency, achieving statistical significance at some doses. Early treatment of SSSE with BRV 10 mg/kg significantly reduced long-term SRS frequency.. These findings support clinical evaluation of BRV for treatment of status epilepticus or acute repetitive seizures.

Topics: Animals; Anticonvulsants; Dentate Gyrus; Diazepam; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Therapy, Combination; Electrodes, Implanted; Electroencephalography; Evoked Potentials; Infusions, Intravenous; Long-Term Care; Male; Perforant Pathway; Pyrrolidinones; Rats; Rats, Wistar; Signal Processing, Computer-Assisted; Status Epilepticus

Brivaracetam (BRV) is a new antiepileptic drug candidate rationally designed for high affinity and selectivity for the synaptic vesicle protein 2A. This study explored anti-ictogenic and antiepileptogenic effects of BRV in rats at different stages of development.. Using a rapid kindling model in P14, P21, P28, and P60 rats, we studied two doses of BRV: 10 and 100 mg/kg injected intraperitoneally 30 min before afterdischarge assessment. We also assessed blood and brain concentrations of BRV 30 min after the injection.. BRV 100 mg/kg significantly increased the afterdischarge threshold (ADT) at all ages, whereas BRV at 10 mg/kg increased ADT in P60, P28, and P21 rats. BRV also shortens the afterdischarge duration (ADD), achieving statistical significance with 10 and 100 mg/kg at P60 and with 100 mg/kg at P21. At P60, BRV increases the number of stimulations required to achieve a stage 4-5 seizure in a dose-dependent manner. At P28 and P21, BRV increased the number of stimulations required to develop a stage 4-5 seizure in a dose-dependent manner with almost complete elimination of stage 4-5 seizures. In contrast, at P14, BRV had no effect on the number of stage 4-5 seizures. An age-related decrease in blood and brain concentrations of BRV was observed 30 min after injection of BRV 10 mg/kg, whereas with 100 mg/kg there were no significant age-correlated differences in brain and serum BRV concentrations.. BRV exerted dose-dependent anti-ictogenic effects from P60 to P14 independent of brain maturation. BRV also exhibited antiepileptogenic effects at P60, whereas this effect need to be further evaluated at P28 and P21. We did not observe any effect on epileptogenesis at P14 at either dose.

Topics: Age Factors; Analysis of Variance; Animals; Animals, Newborn; Anticonvulsants; Disease Models, Animal; Dose-Response Relationship, Drug; Electric Stimulation; Electroencephalography; Epilepsy; Hippocampus; Kindling, Neurologic; Male; Pyrrolidinones; Rats; Rats, Wistar

Topics: Acetamides; Animals; Anticonvulsants; Disease Models, Animal; Indoles; Levetiracetam; Ligands; Membrane Glycoproteins; Mice; Nerve Tissue Proteins; Piracetam; Pyrrolidinones; Rats; Seizures; Synaptic Vesicles

Previous examinations demonstrated antidystonic effects of the synaptic vesicle protein 2A (SV2A) ligand levetiracetam in the dt(sz) mutant hamster, an animal model of paroxysmal non-kinesiogenic dyskinesia in which dystonic episodes can be induced by stress. In the present study, we examined the effects of the two new, high affinity SV2A ligands, brivaracetam and seletracetam, in comparison to levetiracetam on the severity of dystonia in mutant hamsters. Seletracetam (50 and 75 mg/kg i.p.) and brivaracetam (75 mg/kg i.p.) reduced the severity of dystonia to a comparable extent as levetiracetam (50 and 75 mg/kg i.p.). These data confirm the therapeutic potential of these pyrrolidone derivatives for the treatment of paroxysmal dystonia.

Topics: Animals; Cricetinae; Disease Models, Animal; Dose-Response Relationship, Drug; Dystonia; Humans; Levetiracetam; Ligands; Membrane Glycoproteins; Nerve Tissue Proteins; Piracetam; Pyrrolidinones; Severity of Illness Index

Screening of 12,000 compounds for binding affinity to the synaptic vesicle protein 2A (SV2A), identified a high-affinity pyrrolidone derivative, brivaracetam (ucb 34714). This study examined its pharmacological profile in various in vitro and in vivo models of seizures and epilepsy, to evaluate its potential as a new antiepileptic drug.. The effects of brivaracetam and levetiracetam on epileptiform activity and seizure expression were examined in rat hippocampal slices, corneally kindled mice, audiogenic seizure-susceptible mice, maximal electroshock and pentylenetetrazol seizures in mice, hippocampal-kindled rats, amygdala-kindled rats and genetic absence epilepsy rats.. Brivaracetam and levetiracetam reduced epileptiform responses in rat hippocampal slices, brivaracetam being most potent. Brivaracetam also differed from levetiracetam by its ability to protect against seizures in normal mice induced by a maximal electroshock or maximal dose of pentylenetetrazol. In corneally kindled mice and hippocampal-kindled rats, brivaracetam induced potent protection against secondarily generalized motor seizures and showed anti-kindling properties superior to levetiracetam. In amygdala-kindled rats, brivaracetam induced a significant suppression in motor-seizure severity and, contrary to levetiracetam, reduced the after-discharge at a higher dose. Audiogenic seizure-susceptible mice were protected more potently against the expression of clonic convulsions by brivaracetam than by levetiracetam. Brivaracetam induced a more complete suppression of spontaneous spike-and-wave discharges in genetic absence epilepsy rats than levetiracetam.. Brivaracetam has higher potency and efficacy than levetiracetam as an anti-seizure and anti-epileptogenic agent in various experimental models of epilepsy, and a wide therapeutic index.

Topics: Animals; Anticonvulsants; Disease Models, Animal; Electroshock; Epilepsy; Hippocampus; Levetiracetam; Ligands; Male; Membrane Glycoproteins; Mice; Nerve Tissue Proteins; Piracetam; Pyrrolidinones; Rats; Rats, Sprague-Dawley; Seizures

In the present study, we evaluated the anti-seizure and anti-myoclonic activity of levetiracetam and brivaracetam in an established rat model of cardiac arrest-induced post-hypoxic myoclonus. We found that brivaracetam (0.3 mg/kg, the minimal effective dose) was more potent than levetiracetam (3 mg/kg, the minimal effective dose) against post-hypoxic seizures. The anti-seizure activity of both compounds occurred 30 min following intraperitoneal (i.p.) administration and was maintained over the entire 150 min post-dose observation period. Both brivaracetam and levetiracetam significantly reduced auditory stimulated post-hypoxic myoclonus from a dose 0.3 mg/kg. At that dose, the anti-myoclonic activity of brivaracetam was already maximal whereas it continued to increase in a dose-relation manner with levetiracetam, suggesting that brivaracetam is a more potent agent. The onset and the duration of anti-myoclonic activity of both compounds were similar. These findings demonstrate that brivaracetam possesses more potent anti-seizure and anti-myoclonic activity than levetiracetam in an established rat model of cardiac arrest-induced post-hypoxic myoclonus.

Topics: Animals; Anticonvulsants; Disease Models, Animal; Dose-Response Relationship, Drug; Epilepsies, Myoclonic; Heart Arrest; Hypoxia; Levetiracetam; Piracetam; Pyrrolidinones; Rats; Rats, Sprague-Dawley; Seizures