Phase I Study of the Bifunctional Fusion Protein Bintrafusp Alfa in Asian Patients with Advanced Solid Tumors, Including a Hepatocellular Carcinoma Safety-Assessment Cohort

[摘要] Background. Bintrafusp alfa is a first-in-class bifunctional fusion protein composed of the extracellular domain of transforming growth factor-β (TGF-β) RII receptor (a TGF-β “trap”) fused to a human immunoglobulin (Ig) G1 antibody blocking programmed death-ligand 1 (PD-L1). Bintrafusp alfa is designed to neutralize TGF-β signaling by “trapping” and sequestering all TGF-β isoforms, and this trap function is physically linked to PD-L1 blockade in the tumor microenvironment. Methods. NCT02699515 was a phase I, open-label, doseescalation study of bintrafusp alfa (3, 10, and 20 mg/kg every 2 weeks) in Asian patients with advanced solid tumors, including a hepatocellular carcinoma (HCC) safety-assessment cohort. The primary objective was safety and tolerability; the secondary objective is best overall response. Results. As of August 24, 2018, 23 patients (including 9 in the HCC cohort) received bintrafusp alfa. Eight patients experienced treatment-related adverse events (TRAEs). Three patients had grade 3 TRAEs (13.0%; hypoacusis, hyponatremia, hypopituitarism, increased blood creatine phosphokinase, and intracranial tumor hemorrhage); one had grade 4 hyponatremia (4.3%). No treatment-related deaths occurred. In the dose-escalation cohort, two patients had a confirmed partial response, and 3 had stable disease (SD), for an overall response rate of 14.3% and a disease control rate (DCR) of 35.7%. In the HCC cohort, one patient had SD (DCR, 11.1%). A dose-proportional pharmacokinetics profile was observed at doses of >3 mg/kg. Conclusion. Bintrafusp alfa had a manageable safety profile and preliminary efficacy in heavily pretreated patients with advanced solid tumors, including HCC.

[学科分类] 地质学