New antiepileptic drugs

Synthesis of deoxybenzoins from β-alkoxy styrenes and arylboronic acids via palladium-catalyzed regioselective Heck-arylation reactions

Palladium-catalyzed synthesis of deoxybenzoin derivatives from styryl ethers and arylboronic acids is reported. The reaction proceeds under mild conditions in the presence of TEMPO and provides the desired products in good to excellent yields. Simple operation, broad substrate scope, and functional group tolerance are the salient features of the developed methodology.

Radiolabeling of Zonisamide for a Diagnostic Perspective

OBJECTIVE

Epilepsy is one of the oldest and the most common chronic neurological diseases. Antiepileptic drugs (AEDs) are the backbone of epilepsy treatment. However, epileptogenesis has not been fully elucidated. One of the critical reasons for this is the lack of reliable biomarkers. Neuroimaging suggests a non-invasive examination and investigation tool that can detect critical pathophysiological changes involved in epileptogenesis and monitor disease progression. In the current study, the radiolabeling potential of Zonisamide (ZNS) (the secondgeneration AED) with Technetium-99m (99mTc) is examined to neuroimage the epileptogenic processes by contributing to the development of potential radiotracers.

METHODS

ZNS was labeled with 99mTc and the radiochemical yield of [99mTc]Tc-ZNS was determined with TLRC (Thin Layer Liquid Radio Chromatography and HPLRC (High Performance Liquid Radio Chromatography) radiochromatographic methods. In vitro behavior of [99mTc]Tc-ZNS was determined with time-dependent uptake of [99mTc]Tc-ZNS on the SHSY5Y human neuroblastoma cells.

RESULTS

The radiochemical yield of [99mTc]Tc-ZNS was determined as 98.03 ± 1.24% (n = 6) according to radiochromatographic studies results. [99mTc]Tc-ZNS demonstrated 5.38 and 6.18 times higher uptake values than the control group on the human neuroblastoma SH-SY5Y cell line at 120 and 240 minutes, respectively.

CONCLUSION

This study showed that the current radiolabeled antiepileptic drug has a diagnostic potential to be used in imaging neurological processes.

Synthesis, resolution and anticonvulsant activity of chiral N-1'-ethyl,N-3'-(1-phenylethyl)-(R,S)-2'H,3H,5'H-spiro-(2-benzofuran-1,4'-imidazolidine)-2',3,5'-trione diastereomers

Four new N-1',N-3'-disubstituted-2'H,3H,5'H-spiro-(2-benzofuran-1,4'-imidazolidine)-2',3,5'-triones bearing a chiral N-3' substituent were synthesized, resolved and their anticonvulsant activity was obtained and determined that the activity was not stereoselective.

The role of prophylactic anticonvulsants in the management of brain metastases: a systematic review and evidence-based clinical practice guideline

Do prophylactic anticonvulsants decrease the risk of seizure in patients with metastatic brain tumors compared with no treatment?

Target population

These recommendations apply to adults with solid brain metastases who have not experienced a seizure due to their metastatic brain disease.

Recommendation

Level 3 For adults with brain metastases who have not experienced a seizure due to their metastatic brain disease, routine prophylactic use of anticonvulsants is not recommended.

Only a single underpowered randomized controlled trial (RCT), which did not detect a difference in seizure occurrence, provides evidence for decision-making purposes.

Pharmacotherapy of epilepsy: new armamentarium, new issues

Since 1990 there have been over ten antiepileptic drugs (AEDs) approved for the therapy of epilepsy. These agents have a new spectrum of efficacy and novel adverse effects, some totally unexpected. They also represent an enormous escalation of costs. Few have been subjected to head-to-head comparisons in monotherapy against established AEDs. The aim of therapy is to eliminate rather than to reduce seizure manifestations. Many traditional agents have been phased out due to poor tolerability. New epilepsy syndromes and genetic contributions to epilepsy have been refined. Special considerations apply to various classes of sufferers such as the elderly, women of childbearing age, and sufferers with concomitant disorders, treated with medications capable of drug interactions. There is a recognition of the value of slow introduction, a preference for monotherapy, recognition of the effects of AEDs on hormones and reproductive function and effects on the fetus exposed to AEDs in utero, comprising physical malformations and effects on cognitive development. A balance between efficacy and safety is pivotal, as every preference about the initial pharmacotherapy of epilepsy and subsequent polytherapy has its protagonists. With improvement in diagnostic techniques and new therapeutic modalities it is likely that in the future, pharmacogenomics and an understanding of pharmacoresistance may influence drug selection for individual patients with epilepsy.

Analysis of antiepileptic drugs use at a university hospital in Croatia

To analyse the consumption rate of new generation antiepileptic drugs (AEDs) compared with traditional AEDs at a university hospital in Croatia. Antiepileptic drugs use was analysed retrospectively for two consecutive years, 2001 and 2002 at Departments of Neurology, Paediatrics, Psychiatry and Neurosurgery at the University Hospital Centre (UHC) Rijeka. The results obtained are expressed as number of defined daily doses (DDDs) per 100 bed days, as proposed by the WHO. The use of new generation AEDs was represented by 2% in 2001 and 5% in 2002. Majority of AEDs administered was taken by the barbiturates in both years. A wide spectrum of AEDs has been used at the Department of Paediatrics. At the Department of Neurology and Psychiatry use of barbiturates and carbamazepine predominated. The use of new AEDs at UHC has increased during the investigation period but it is still rather low compared with traditional AEDs. The similarity of our results with the result of the leading Croatian university hospitals might represent general routine AED prescription in country. Nationally based guidelines may bring more appropriate and rational approach for usage of modern AED. This task should be supported and promoted by international and national neurology associations.

Seizure worsening with topiramate amongst Indians with refractory epilepsy

In a prospective open label add-on study on 95 patients (age 1-63 years, mean 17.76 +/- 13.83 years) with seizures refractory to conventional antiepileptic drugs (AEDs) and other new AEDs, the addition of Topiramate (TPM) resulted in seizure worsening in 18 patients (19%) necessitating drug withdrawal over an average follow-up period of 4.94 +/- 1.69 months. Patients who had seizure worsening were older (P = 0.02), were more likely to have had a history of status epilepticus in the past (P = 0.03), were on three conventional AEDs (P = 0.027) or had tried one of the other new AEDs in the past with poor response (P = 0.04). Seven of 18 patients who had seizure worsening with TPM (7.4%) experienced initial seizure worsening, probably representing the subgroup with 'true' seizure worsening whilst 11 (11.6%) had initial improvement followed by 'apparent' seizure worsening. Initial seizure worsening was noted to be significantly more in females when compared with males who worsened after initial improvement (P = 0.05).

Epilepsy

Epilepsy may be associated with major social and medical problems, and counselling of patient and family is essential for good management. The workup of a person with a seizure includes history, physical examination, and laboratory testing. An electroencephalogram is essential to help classify the seizure and epilepsy type. Neuroimaging (preferably by magnetic resonance imaging) helps to exclude a structural abnormality. Seizures can be controlled with a single drug (monotherapy) in 70% of patients. The incidence of drug side effects is increased if more than one drug is used. Pregnancy is associated with an increased risk of seizures in 30% of women with epilepsy. Frequent assessment throughout pregnancy is important. There is a slightly increased risk of congenital malformation associated with the antiepileptic drugs. Folic acid supplementation is advisable.