Purpose: Dinutuximab (Unituxin™; ch14.18), a monoclonal antibody against disialoganglioside, improved survival as part of post-consolidation therapy for high-risk neuroblastoma. United Therapeutics Corporation (UTC) assumed ch14.18 production from the National Cancer Institute (NCI); this study evaluates pharmacokinetic comparability, safety, and tolerability of UTC and NCI products.
Methods: In this randomized, two-sequence crossover study, 28 patients aged ≤8 years with high-risk neuroblastoma received equivalent ch14.18-UTC or ch14.18-NCI doses. Despite comparable protein content, nominal doses differed: 17.5 mg/m(2)/day (ch14.18-UTC) and 25 mg/m(2)/day (ch14.18-NCI). Patients received one product during therapy cycles 1 and 2, the other during cycles 3-5. Ch14.18 pharmacokinetic profile characterization used population modeling (NONMEM(®) version 7.2). A two-compartment model with first-order distribution and elimination processes described pharmacokinetic data. Estimated product parameters were normalized to UTC nominal dose. For pharmacokinetic comparability, the final model was used to estimate exposure ratios (UTC/NCI) and associated 90 % confidence intervals (CIs) for area under the curve from time zero to infinity (AUCinf) and maximum concentration (C max). All comparisons were based on a standardized single-dose regimen (17.5 mg/m(2) over 10 h).
Results: Final-model pharmacokinetic parameters were similar to previously published ch14.18-NCI parameters and comparable for UTC and NCI products. Products' systemic exposures were comparable, with 90 % CIs around ratios for AUCinf (0.96; 90 % CI 0.88-1.04) and C max (1.04; 90 % CI 0.98-1.11) within standard bioequivalence bounds (90 % CI 0.80-1.25). Products' adverse events were similar and consistent with those previously reported.
Conclusions: Equivalent actual ch14.18-UTC and ch14.18-NCI doses produced comparable exposures, with no notable safety or tolerability differences.
Keywords: Dinutuximab; Pharmacokinetics; Safety; Tolerability; Unituxin; ch14.18.