Vigabatrin in childhood epilepsy

Jackson MC, Jafarpour S, Klehm J, Thome-Souza S, Coughlin F, Kapur K, Loddenkemper T. Effect of vigabatrin on seizure control and safety profile in different subgroups of children with epilepsy. Epilepsia. 2017 Jul 10. doi:10.1111/epi.13836. [Epub ahead of print]

Abstract

OBJECTIVE:

To evaluate the efficacy and safety of vigabatrin in pediatric epilepsy.

METHODS:

We retrospectively reviewed patients with epilepsy treated with vigabatrin over a 2-year period at a pediatric tertiary center. We assessed the relationship between seizure frequency, etiology, vigabatrin dose, adverse events, medication discontinuation reasons, and electroencephalography (EEG) characteristics.

RESULTS:

One hundred three patients followed at Boston Children's Hospital were treated with vigabatrin and had complete medical records. Within the follow-up interval, 69 (67%) of 103 patients had discontinued vigabatrin therapy. Two patients (1.9%) died during therapy for unknown reasons. Median age at vigabatrin initiation was 8 months (interquartile range [IQR] 5-15). Median starting dose was 48.1 mg/kg per day (IQR 29.8-52.3) with a median target of 100 mg/kg (IQR 81.9-107.9). Median treatment duration was 12.1 months (n = 89, IQR 5.0-22.9) overall, and 13.3 months (IQR 5.2-23.2) for patients who discontinued vigabatrin. The most common reasons for discontinuation were controlled seizures in 31 (43.7%) of 71 and unsatisfactory therapeutic effect in 23 (32.4%) of 71. Median percent seizure reduction from baseline to first follow-up was 83.3% (IQR 27.4-99.8) and 96.7% (IQR 43.3-100) to last follow-up. Twenty-four (38.7%) of 62 patients with a follow-up posttreatment remained seizure-free. Four patients who had initially achieved seizure freedom relapsed. Patients with structural/metabolic etiology had greater median percent seizure reduction at first follow-up than patients with genetic etiology (98.7% vs. 61.4%, respectively, p = 0.001). Hypsarrhythmia resolved after therapy in 18 of 20 (90%, 95% confidence interval [CI] 70-97) patients with pretreatment hypsarrhythmia, and 2 patients presented with hypsarrhythmia posttreatment. Risk of having hypsarrhythmia was reduced by 32% (95% CI 14.9-49.1) posttreatment.

SIGNIFICANCE:

Vigabatrin is efficacious in all seizure types and resolved hypsarrhythmia in most patients. In this series with a median treatment duration of 12.1 months, vigabatrin had a good safety profile with a low rate of discontinuation due to nonophthalmologic and ophthalmologic adverse effects.

The clinicians undertook this study to assess the efficacy and safety of vigabatrin in pediatric epilepsy. In all seizure types, vigabatrin was efficacious and resolved hypsarrhythmia in most patients. Vigabatrin had a good safety profile with a low rate of discontinuation because of nonophthalmologic and ophthalmologic adverse effects in this series with a median treatment duration of 12.1 months.

_____________________________________________________________________

Methods

For this study, the clinicians retrospectively evaluated patients with epilepsy treated with vigabatrin over a 2-year period at a pediatric tertiary center.

The relationship between seizure frequency, etiology, vigabatrin dose, adverse events, medication discontinuation reasons, and electroencephalography (EEG) characteristics were evaluated.

Results

The clinicians treated 103 patients followed at Boston Children's Hospital with vigabatrin and had complete medical records.

69 (67%) of 103 patients had discontinued vigabatrin therapy within the follow-up interval.

During therapy, 2 patients (1.9%) died for unknown reasons.

At vigabatrin initiation, median age was 8 months (interquartile range [IQR] 5-15).

With a median target of 100 mg/kg (IQR 81.9-107.9), median starting dose was 48.1 mg/kg per day (IQR 29.8-52.3).

Overall median treatment duration was 12.1 months (n = 89, IQR 5.0-22.9), and 13.3 months (IQR 5.2-23.2) for patients who discontinued vigabatrin.

For discontinuation, the most common reasons were controlled seizures in 31 (43.7%) of 71 and unsatisfactory therapeutic effect in 23 (32.4%) of 71.

From baseline to first follow-up, median percent seizure reduction was 83.3% (IQR 27.4-99.8) and 96.7% (IQR 43.3-100) to last follow-up.

24 (38.7%) of 62 patients with a follow-up posttreatment remained seizure-free.

In this study, 4 patients who had initially obtained seizure freedom relapsed.

At first follow-up, patients with structural/metabolic etiology had greater median percent seizure reduction compared to patients with genetic etiology (98.7% vs. 61.4%, respectively, p = 0.001).

After therapy, hypsarrhythmia resolved in 18 of 20 (90%, 95% confidence interval [CI] 70–97) patients with pretreatment hypsarrhythmia, and 2 patients presented with hypsarrhythmia posttreatment.

As per the outcomes, the risk of having hypsarrhythmia was decreased by 32% (95% CI 14.9-49.1) posttreatment.

https://www.mdlinx.com/neurology/medical-news-article/2017/07/11/vigabatrin-seizure-children-epilepsy/7242606/?category=latest&page_id=1