Levetiracetam Versus Fosphenytoin Infusions as Second-Line Treatment for Pediatric Status Epilepticus: A Multicenter Study Examining Effectiveness, Tolerability, and Ease of Use

Abstract

Background and objectives: Status epilepticus is a life-threatening neurological emergency that requires rapid and effective treatment to prevent long-term complications or death. Traditionally, phenytoin and its prodrug fosphenytoin have been used as second-line therapies following benzodiazepines. However, intravenous levetiracetam has emerged as a promising alternative because of its favorable safety profile and ease of administration, particularly in pediatric populations. This study aimed to evaluate whether intravenous levetiracetam was non-inferior to intravenous fosphenytoin as a second-line treatment for managing pediatric status epilepticus.

Methods: From November 2021 to May 2023, we implemented an updated local protocol that replaced fosphenytoin with levetiracetam as the second-line treatment for status epilepticus. Following this change, we conducted a 2-year multicenter study to evaluate its impact. For comparison, we also included patients treated under the previous protocol during the 2 years prior to the change, as a control group. An inverse probability of treatment weighting approach, based on the propensity score, was used to adjust for baseline characteristics between the two groups. Bayesian regression models were used to assess treatment effects in the weighted cohort. Treatment effectiveness was assessed using a composite measure of need for subsequent interventions, recurrence of status epilepticus within 24 h, seizure duration and length of hospital stay. We tested non-inferiority hypotheses for effectiveness criteria and if the probability of non-inferiority was greater than 95%, we also tested a superiority hypothesis. Safety was assessed by analyzing adverse events, mortality, admission to the intensive care unit, and transfer to the resuscitation unit. For safety criteria, only superiority was tested.

Results: In total, 127 patients with status epilepticus were evaluated during the study period; 84 patients in the fosphenytoin group (66%) and 43 patients in the levetiracetam group (34%). Of these, 52 patients had febrile status epilepticus (40.9%), 27 patients were treated with oral levetiracetam as part of their daily treatment regimen at the time of status epilepticus (21.3%), and 12 (9.4%) patients had been treated with levetiracetam during their lifetime but stopped at the time of status epilepticus. With intravenous levetiracetam, 62.8% of children were seizure free, compared with 37.2% of children taking fosphenytoin. The length of hospital stay was significantly shorter with levetiracetam than with fosphenytoin (reduction of 1.9 days with levetiracetam) and children were less likely to be admitted to the intensive care unit (reduction of 18.1% with levetiracetam). The need for third-line treatment or seizure recurrence was significantly lower in the levetiracetam group (16.3% reduction compared with fosphenytoin). Adverse effects and seizure duration were not significantly different between the two groups.

Conclusions: Using a composite outcome measure, we demonstrated that levetiracetam was not inferior to fosphenytoin with respect to seizure recurrence, the need for third-line therapy, intensive care unit admission, and the total length of hospital stays.