CONVECTION-ENHANCED delivery in pediatric patients produced mild adverse events in most studies with no Grade 4 or 5 toxicity seen.
Convection-Enhanced Delivery Addresses the Blood-Brain Barrier
Convection-enhanced delivery (CED) is a developing drug delivery approach that aims to bypass the blood-brain barrier by placing therapeutics directly into the brain parenchyma. In a systematic review, investigators aggregated published pediatric CED protocols and adverse events to benchmark safety as this technique expands into new clinical applications.
Using a modified PRISMA workflow, the authors screened 108 unique records and included 12 studies for data extraction, representing 162 pediatric patients. The mean age was 8.64 years, with a reported range of 5–14.1 years.
Convection-Enhanced Delivery Protocols in Pediatric Patients
Most pediatric CED use to date has focused on treatment-resistant neuro-oncology. Across the included studies, 92% of patients received convection-enhanced delivery for unresectable high-grade glioma, and 83% were treated for diffuse intrinsic pontine glioma. The remaining cases involved genetic enzyme deficiency.
Protocol characteristics varied, but a trans-frontal approach was the most frequently reported route (58%). Single catheter systems were used in half of studies, reflecting ongoing efforts to balance surgical complexity with reliable intraparenchymal drug distribution.
Safety Profile of Convection-Enhanced Delivery
Across studies, 285 adverse events were reported. Headache (20%) and limb weakness (18.2%) were the most common, followed by Grade 1 cranial nerve deficits (6.3%) and general pain (4.9%). Where Common Terminology Criteria for Adverse Events grading was provided, 125 of 132 events (94.7%) were Grade 1 or Grade 2, and 7 (5.3%) were Grade 3. No Grade 4 or Grade 5 adverse events occurred.
These findings suggest that mild side effects are common after convection-enhanced delivery in pediatric patients, while severe complications appear rare within the current evidence base. The authors emphasize the need for multi-institutional and longitudinal datasets to refine best practices, standardize protocols, and better define how CED should be integrated into investigational therapy pipelines for pediatric CNS disease.
Reference: Fredricks NS et al. Protocols and safety profile of convection enhanced delivery in pediatric patients: a systematic review. Childs Nerv Syst. 2026;42:30.
