Benralizumab in children with severe eosinophilic asthma: Pharmacokinetics and long-term safety (TATE study)

Background: Benralizumab is an anti-interleukin-5 receptor α monoclonal antibody approved as an add-on maintenance treatment for patients with uncontrolled severe asthma. Prior Phase 3 studies have evaluated benralizumab in patients aged ≥12 years with severe uncontrolled asthma. The TATE study evaluated the pharmacokinetics (PK), pharmacodynamics (PD), and safety of benralizumab treatment in children. Methods: TATE was an open-label, Phase 3 study of benralizumab in children aged 6–11 years from the United States and Japan (plus participants aged 12–14 years from Japan) with severe eosinophilic asthma. Participants received benralizumab 10/30 mg according to weight (<35/≥35 kg). Primary endpoints included maximum serum concentration (C_max), clearance, half-life (t_1/2), and blood eosinophil count. Clearance and t_1/2 were derived from a population PK (popPK) analysis. Safety and tolerability were also assessed. Results: Twenty-eight children aged 6–11 years were included, with an additional two participants from Japan aged 12–14 years also included in the popPK analysis. Mean C_max was 1901.2 and 3118.7 ng/mL in the 10 mg/<35 kg and 30 mg/≥35 kg groups, respectively. Clearance was 0.257, and mean t_1/2 was 14.5 days. Near-complete depletion of blood eosinophils was shown across dose/weight groups. Exploratory efficacy analyses found numerical improvements in mean FEV₁, mean ACQ-IA, patient/clinician global impression of change, and exacerbation rates. Adverse events occurred in 22/28 (78.6%) of participants; none led to discontinuation/death. Conclusion: PK, PD, and safety data support long-term benralizumab in children with severe eosinophilic asthma, and were similar to findings in adolescents and adults. Trial Registration: ClinicalTrials.gov-ID: NCT04305405.