A Phase 1 Study of Intravenous EGFR-ErbituxEDVsMIT in Children with Solid or CNS Tumours Expressing Epidermal Growth Factor Receptor.

Abstract

Background: Recurrent or refractory solid and central nervous system (CNS) tumours in paediatric patients have limited treatment options and carry a poor prognosis. The EnGeneIC Dream Vector (EDV) is a novel nanocell designed to deliver cytotoxic medication directly to the tumour. The epidermal growth factor receptor is expressed in several CNS and solid tumours and is the target for bispecific antibodies attached to the EDV.

Objective: To assess the safety and tolerability of EGFR-Erbitux receptor EnGeneIC Dream Vector with mitoxantrone (^EEDVs_Mit) in children with recurrent / refractory solid or CNS tumours expressing EGFR.

Patients and methods: Patients aged 2-21 years with relapsed or refractory CNS and solid tumours, or radiologically diagnosed diffuse intrinsic pontine glioma (DIPG), were treated in this phase I open-label study of single agent ^EEDVs_Mit. Thirty-seven patients' tumours were screened for EGFR expression. ^EEDVs_Mit was administered twice weekly in the first cycle and weekly thereafter. Standard dose escalation with a rolling 6 design was employed. Dosing commenced at 5 × 10^{8 E}EDVs_Mit per dose and escalated to 5 × 10^{9 E}EDVs_Mit per dose.

Results: EGFR expression was detected in 12 (32%) of the paediatric tumours tested. Nine patients were enrolled and treated on the trial, including three patients with diffuse midline glioma. Overall, ^EEDVs_Mit was well tolerated, with no dose-limiting toxicities observed. The most common drug-related adverse events were grade 1-2 fever, nausea and vomiting, rash, lymphopaenia, and mildly deranged liver function tests. All patients had disease progression, including one patient who achieved a mixed response as the best response.

Conclusions: EGFR-Erbitux receptor targeted EnGeneIC Dream Vector with mitoxantrone can be safely delivered in paediatric patients aged 2-21 years with solid or CNS tumours harbouring EGFR expression. The discovery of EGFR expression in a high proportion of paediatric gliomas means that EGFR may be useful as a target for other treatment strategies. Targeted therapeutic-loaded EDVs may be worth exploring further for their role in stimulating an anti-tumour immune response.

Clinicaltrials:

Gov identifier: NCT02687386.