Teratogenic potential of third-generation antiepileptic drugs: Current status and research needs

Predictors of Seizure Recurrence in Women With Idiopathic Generalized Epilepsy Who Switch From Valproate to Another Medication

BACKGROUND AND OBJECTIVES

To investigate the predictors of seizure recurrence in women of childbearing age with idiopathic generalized epilepsy (IGE) who switched from valproate (VPA) to alternative antiseizure medications (ASMs) and compare the effectiveness of levetiracetam (LEV) and lamotrigine (LTG) as VPA alternatives after switch.

METHODS

This multicenter retrospective study included women of childbearing age diagnosed with IGE from 16 epilepsy centers. Study outcomes included worsening or recurrence of generalized tonic-clonic seizure (GTCS) at 12 months and 24 months after the switch from VPA to an alternative ASM. The comparative effectiveness of LEV and LTG as alternative ASM following VPA discontinuation was assessed through inverse probability treatment-weighted (IPTW) Cox regression analysis.

RESULTS

We included 426 women with IGE, with a median (interquartile range) age at VPA switch of 24 (19-30) years and a median VPA dosage of 750 (500-1,000) mg/d. The most common reason for VPA switch was teratogenicity concern in 249 women (58.6%), and the most common ASM used in place of VPA was LEV in 197 (46.2%) cases, followed by LTG in 140 (32.9%). GTCS worsening/recurrence occurred in 105 (24.6%) and 139 (32.6%) women at 12 and 24 months, respectively. Catamenial worsening of seizures, higher VPA dosage during switch, multiple seizure types, and shorter duration of GTCS freedom before switch were independent predictors of GTCS recurrence or worsening at 12 months according to mixed multivariable logistic regression analysis. After internal-external validation through 16 independent cohorts, the model showed an area under the curve of 0.71 (95% CI 0.64-0.77). In the subgroup of 337 women who switched to LEV or LTG, IPTW Cox regression analysis showed that LEV was associated with a reduced risk of GTCS worsening or recurrence compared with LTG (adjusted hazard ratio 0.59, 95% CI 0.40-0.87, p = 0.008) during the 24-month follow-up.

DISCUSSION

Our findings can have practical implications for optimizing counselling and treatment choices in women of childbearing age with IGE and may help clinicians in making informed treatment decisions in this special population of patients.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that for women with IGE switching from VPA, LEV was associated with a reduced risk of GTCS worsening or recurrence compared with LTG.

Machine Learning to Predict Teratogenicity: Theory and Practice

Machine learning (ML) is a subfield of artificial intelligence (AI) that consists of developing algorithms that can automatically learn patterns and relationships from data, without being explicitly programmed. It continues to advance with the development of more sophisticated algorithms, increased computational power, and larger datasets, leading to significant advancements in AI technology. With the significant progress made in ML, the need to apply these systems in the area of teratogenicity is growing. It is sought as robust boosting methods to overcome many limitations and restrictions facing the experimental studies. By performing tasks such as classification, regression, clustering, anomaly detection, and decision systems, ML can be used to assess whether an agent is teratogen or not or to determine its teratogenic potential. It may also be used for the purpose of deciding on the use of medicinal products. In this chapter, we describe how ML can be used to investigate teratogenicity.

Birth outcomes in pregnant women with epilepsy: A Nationwide multicenter study from Türkiye

OBJECTIVE

The present study was aimed at investigating the effects of anti-seizure medications (ASMs), patient demographic characteristics, and the seizure type and frequency on the development of congenital malformations (CMs) in the infants of pregnant women with epilepsy (PWWE).

METHODS

PWWE followed up at the neurology outpatient clinic of 21 centers between 2014 and 2019 were included in this prospective study. The follow-up of PWWE was conducted using structured, general pregnant follow-up forms prepared by the Pregnancy and Epilepsy Study Committee. The newborns were examined by a neonatologist after delivery and at 1 and 3 months postpartum.

RESULTS

Of the infants of 759 PWWE, 7.2% had CMs, with 5.6% having major CMs. Polytherapy, monotherapy, and no medications were received by 168 (22.1%), 548 (72.2 %), and 43 (5.7 %) patients, respectively. CMs were detected at an incidence of 2.3% in infants of PWWE who did not receive medication, 5.7% in infants of PWWE who received monotherapy, and 13.7% in infants of PWWE who received polytherapy. The risk of malformation was 2.31-fold (95% confidence interval (CI): 1.48-4.61, p < .001) higher in infants of PWWE who received polytherapy. Levetiracetam was the most frequently used seizure medication as monotherapy, with the highest incidence of CMs occurring with valproic acid (VPA) use (8.5%) and the lowest with lamotrigine use (2.1%). The incidence of CMs was 5% at a carbamazepine dose <700 mg, 10% at a carbamazepine dose ≥700 mg, 5.5% at a VPA dose <750 mg, and 14.8% at a VPA dose ≥750 mg. Thus the risk of malformation increased 2.33 times (p = .041) in infants of PWWE receiving high-dose ASMs.

SIGNIFICANCE

Birth outcomes of PWWE receiving and not receiving ASMs were evaluated. The risk of CMs occurrence was higher, particularly in infants of PWWE using VPA and receiving polytherapy. The incidence of CMs was found to be lower in infants of PWWE receiving lamotrigine.

Fighting Epilepsy with Nanomedicines-Is This the Right Weapon?

Epilepsy is a chronic and complex condition and is one of the most common neurological diseases, affecting about 50 million people worldwide. Pharmacological therapy has been, and is likely to remain, the main treatment approach for this disease. Although a large number of new antiseizure drugs (ASDs) has been introduced into the market in the last few years, many patients suffer from uncontrolled seizures, demanding the development of more effective therapies. Nanomedicines have emerged as a promising approach to deliver drugs to the brain, potentiating their therapeutic index. Moreover, nanomedicine has applied the knowledge of nanoscience, not only in disease treatment but also in prevention and diagnosis. In the current review, the general features and therapeutic management of epilepsy will be addressed, as well as the main barriers to overcome to obtain better antiseizure therapies. Furthermore, the role of nanomedicines as a valuable tool to selectively deliver drugs will be discussed, considering the ability of nanocarriers to deal with the less favourable physical-chemical properties of some ASDs, enhance their brain penetration, reduce the adverse effects, and circumvent the concerning drug resistance.

The teratogenic effect of pregabalin on heart, liver and kidney in rats: a light microscopic, electron microscopic and immunohistochemical study

BACKGROUND

Pregabalin (PGB) was approved as new anti-epileptic drugs with little information about its teratogenic effect.

AIM OF THE WORK

to evaluate the developmental toxicity of PGB.

MATERIALS AND METHODS

60 pregnant albino rats were divided into three groups. PGB (500 mg/kg body weight/day) was given to group II, PGB (1250 mg/kg body weight/day) was given to Group III and no medications were given to group I. The pups were normally delivered. Liver, kidney and heart specimens were prepared for histological, immunohistochemical, and morphometric studies.

RESULTS

A dose of 500 mg of PGB had minimal toxic effects in the form of mild collagen deposition and moderate positive caspase-3 immunoexpression. PGB dose of 1250 mg/kg induced gross toxic effects in form of degenerated cardiac myofibres, ruptured blood vessels, vacuolations in the renal cortex, fibrosis and strong positive caspase-3 immunoexpression.

CONCLUSION

PGB at dose of 500 mg/kg revealed minimal toxic changes. PGB cause embryotoxicity in a dose-dependent manner, as the higher dose induced more degenerative changes.

Levetiracetam, lamotrigine and carbamazepine: which monotherapy during pregnancy?

OBJECTIVE

Epilepsy treatment during pregnancy is still challenging. The study is aimed at comparing the efficacy and safety of carbamazepine (CBZ), lamotrigine (LTG) and levetiracetam (LEV) monotherapies during pregnancy in women with focal (FE) or generalized (GE) epilepsy.

METHODS

A multicentre retrospective study was conducted to evaluate seizures frequency and seizure freedom (SF) rate during 3 months before pregnancy, each trimester of gestation and post-partum period in women on monotherapy with CBZ, LTG and LEV.

RESULTS

Fifty-seven pregnancies (45 FE, 12 GE) on monotherapy (29 CBZ, 11 LTG, 17 LEV) were included. A significant reduction of seizure frequency was found in the first trimester of pregnancy as compared with that one before pregnancy (p = 0.004), more evident in GE (p = 0.003) and in LEV group (p = 0.004). The SF rate significantly increased in the first trimester in comparison to that one before pregnancy and persisted in the post-partum period in the whole sample (p < 0.001) and in women on LEV (p = 0.004). Besides, 88.57% of SF women before pregnancy remained unchanged during gestation and the post-partum period. One major heart malformation in CBZ and no major malformations in LTG and LEV groups were found.

CONCLUSIONS

A better clinical outcome during pregnancy emerged since the first trimester in comparison to the before-pregnancy period, mostly evident in women with GE and LEV therapy, reinforcing the hypothesis of a protective role of pregnancy versus seizures. SF before pregnancy represents a significant predictive factor of good clinical outcome during gestation and the post-partum period. Compared to CBZ, LTG and LEV showed a better safety profile.

Stability Indicating Methods for Determination of Third Generation Antiepileptic Drugs and Their Related Substances

The third generation of antiepileptic drugs that have been approved by international regulatory agencies between 2007 and 2018 include rufinamide, stiripentol, eslicarbazepine acetate, lacosamide, perampanel, brivaracetam and everolimus. As part of demonstrating their safety profile, stability indicating methods are developed to monitor these drugs and their impurities. In this context, this review describe some characteristics, impurities and the stability indicating methods used for the determination of these drugs and the presence of their related substances. Through a search in official compendia and scientific articles, fifty-six analytical methodologies were identified up to October 2020. The methodologies were developed using techniques of HPLC, UPLC, HPTLC, GC and UV/Vis spectrophotometry. A majority of the methods (∼70%) employed HPLC-UV. A number of these antiepileptic drugs were found to have had a small number of studies related to their stability and for the detection of impurities. The presentation of the current level of research on third generation antiepileptic drugs highlights the need for new stability and safety studies that are necessary to develop new pharmaceutical products containing these drugs.

Clinical characteristics and fetal outcomes in women with epilepsy with planned and unplanned pregnancy: A retrospective study

PURPOSE

To compare the antiepileptic drug (AED) treatment patterns, seizure control, and folic acid supplementation between planned and unplanned pregnancy in women with epilepsy (WWE) and to investigate the effects of planned pregnancy on fetal outcomes.

METHODS

A prospectively collected database including WWE with pregnancy from Feb 2010 to Dec 2018 was retrospectively analyzed. Planned pregnancy was defined as WWE being regularly supervised by epileptologists from the time of intended pregnancy until delivery. Clinical characteristics and fetal outcomes were compared between the planned and unplanned pregnancy groups. Logistic regression was used to identify modifiable factors associated with adverse fetal outcomes.

RESULTS

A total of 188 planned pregnancies and 289 unplanned pregnancies were enrolled in our study. Among planned pregnancies, 66.0 % took AED monotherapy, and 32.4 % received polytherapy. Among unplanned pregnancies, 58.1 % didn't take AEDs, 28.0 % took monotherapy, and 12.8 % received polytherapy. The planned pregnancies had less generalized tonic-clonic seizures (P = 0.002) and higher proportion of being seizure-free (41.0 % vs. 22.8 %; P <0.001). All planned pregnancies took folic acid while 39.8 % of unplanned pregnancies never took it (P <0.001). The planned pregnancies had less rates of induced abortions (2.7 % vs. 13.5 %; P <0.001), preterm births (3.3 % vs. 20.4 %; P <0.001), and major congenital malformations (1.6 % vs. 7.5 %; P = 0.016). Pregnancy planning was independently associated with adverse fetal outcomes (adjusted OR, 0.14; 95 % CI, 0.08-0.27; P <0.001).

CONCLUSION

Planned pregnancy in WWE contributes to more optimized AED pattern, better seizure control, more appropriate folic acid supplementation, and less adverse fetal outcomes.

Environmental Risk Factors for Congenital Heart Disease

Congenital heart disease (CHD) has many forms and a wide range of causes. Clinically, it is important to understand the causes. This allows estimation of recurrence rate, guides treatment options, and may also be used to formulate public health advice to reduce the population prevalence of CHD. The recent advent of sophisticated genetic and genomic methods has led to the identification of more than 100 genes associated with CHD. However, despite these great strides, to date only one-third of CHD cases have been shown to have a simple genetic cause. This is because CHD can also be caused by oligogenic factors, environmental factors, and/or gene-environment interaction. Although solid evidence for environmental causes of CHD have been available for almost 80 years, it is only very recently that the molecular mechanisms for these risk factors have begun to be investigated. In this review, we describe the most important environmental CHD risk factors, and what is known about how they cause CHD.