Evolocumab in paediatric heterozygous familial hypercholesterolaemia: cognitive function during 80 weeks of open-label extension treatment

Eur J Prev Cardiol. 2024 Feb 15;31(3):302-310. doi: 10.1093/eurjpc/zwad332.

Abstract

Aims: PCSK9 inhibition intensively lowers low density lipoprotein cholesterol and is well tolerated in adults and paediatric patients with familial hypercholesterolaemia (FH). HAUSER-RCT showed that 24 weeks of treatment with evolocumab in paediatric patients did not affect cognitive function. This study determined the effects of 80 additional weeks of evolocumab treatment on cognitive function in paediatric patients with heterozygous FH.

Methods and results: HAUSER-OLE was an 80-week open-label extension of HAUSER-RCT, a randomized, double-blind, 24-week trial evaluating the efficacy and safety of evolocumab in paediatric patients (ages 10-17 years) with FH. During the OLE, all patients received monthly 420 mg subcutaneous evolocumab injections. Tests of psychomotor function, attention, visual learning, and executive function were administered at baseline and Weeks 24 and 80 of the OLE. Changes over time were analysed descriptively and using analysis of covariance. Cohen's d statistic was used to evaluate the magnitude of treatment effects. Analysis of covariance results indicated no decrease in performance across visits during 80 weeks of evolocumab treatment for Groton Maze Learning, One Card Learning accuracy, Identification speed, or Detection speed (all P > 0.05). Performance on all tasks was similar for those who received placebo or evolocumab in the RCT (all P > 0.05). For all tests, the least square mean differences between patients who received placebo vs. evolocumab in the parent study were trivial (all Cohen's d magnitude < 0.2).

Conclusion: In paediatric patients with FH, 80 weeks of open-label evolocumab treatment had no negative impact on cognitive function.

Registration: ClinicalTrials.gov identifier: NCT02624869.

Keywords: Atherosclerotic cardiovascular disease; Central nervous system; Children; Low density lipoprotein cholesterol; Proprotein convertase subtilisin kexin 9 (PCSK9); Safety.

Plain language summary

Some children are born with a genetic disorder that causes high cholesterol, which leads to heart disease. Children with high cholesterol can be treated with evolocumab, a medication that lowers blood cholesterol. Because cholesterol is important for development and adequate function of the brain, there is a concern that lowering cholesterol in children may affect mental ability. In this study, we tested whether treating children with evolocumab for 80 weeks affected mental ability in performing several tasks. A battery of tests that measure executive function (Groton Maze Learning Test), visual learning (One Card Learning Test), visual attention (Identification Test), and psychomotor function (Detection Test) showed no decrease in performance across visits during 80 weeks of evolocumab treatment. Performance on all tasks was similar for the children who received placebo for the first 24 weeks then received evolocumab for an additional 80 weeks (placebo/evolocumab) and those who received evolocumab for 24 weeks then received evolocumab for an additional 80 weeks (evolocumab/evolocumab).

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Antibodies, Monoclonal / therapeutic use
  • Antibodies, Monoclonal, Humanized*
  • Anticholesteremic Agents* / adverse effects
  • Child
  • Cognition
  • Double-Blind Method
  • Humans
  • Hyperlipoproteinemia Type II* / diagnosis
  • Hyperlipoproteinemia Type II* / drug therapy
  • Proprotein Convertase 9
  • Treatment Outcome

Substances

  • evolocumab
  • PCSK9 protein, human
  • Proprotein Convertase 9
  • Anticholesteremic Agents
  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized

Associated data

  • ClinicalTrials.gov/NCT02624869

Grants and funding