Bintrafusp alfa, a bifunctional fusion protein targeting TGF-β and PD-L1, in advanced squamous cell carcinoma of the head and neck: results from a phase I cohort.

BACKGROUND

We report the clinical activity and safety of bintrafusp alfa, a first-in-class bifunctional fusion protein composed of the extracellular domain of the transforming growth factor β (TGF-β)RII receptor (a TGF-β 'trap') fused to a human IgG1 monoclonal antibody blocking programmed death-ligand 1 (PD-L1), in patients with heavily pretreated squamous cell carcinoma of the head and neck (SCCHN).

METHODS

In this phase I dose-expansion cohort, patients with advanced SCCHN not amenable to curative therapy that progressed/recurred after platinum therapy in the recurrent/metastatic setting, or <6 months after platinum therapy in the locally advanced setting, received bintrafusp alfa 1200 mg intravenously every 2 weeks. The primary endpoint was confirmed best overall response (BOR; Response Evaluation Criteria for Solid Tumors (RECIST) 1.1) per independent review committee (IRC); other endpoints included BOR per investigator and safety.

RESULTS

As of August 24, 2018, 32 patients had received bintrafusp alfa (median follow-up 86.4 weeks; range 2-97). Per IRC, the confirmed objective response rate (ORR) was 13% (95% CI 4% to 29%; 4 partial responses (PR)); 4 patients had stable disease (SD) (disease control rate 34%; 95% CI 12% to 43%). Per investigator, there were 5 PRs (ORR, 16%), including 2 patients who developed delayed PRs after initial disease increase (total clinical response rate 22%). Responses (ORRs) were observed in patients with PD-L1-positive (12%), PD-L1-negative (17%; 73-10 antibody for immunohistochemistry), human papillomavirus (HPV)-positive (33%) and HPV-negative tumors (5%). Grade 3 treatment-related adverse events (TRAEs) were reported in 11 patients (34%), with no grade 4 TRAEs or treatment-related deaths.

CONCLUSIONS

Bintrafusp alfa showed clinical activity across subgroups of PD-L1 expression and in HPV-positive tumors and had a manageable safety profile in patients with heavily pretreated advanced SCCHN. Activity in HPV-positive tumors is favorable compared with historical data from PD-L1 inhibitors and is being further investigated in an ongoing study of HPV-associated tumors.

TRIAL REGISTRATION NUMBER

NCT02517398.

Informations de copyright

© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Déclaration de conflit d'intérêts

Competing interests: BCC reports research funding from Novartis, Bayer, AstraZeneca, MOGAM Institute, Dong-A ST, Champions Oncology, Janssen, Yuhan, Ono, Dizal Pharma, MSD; consulting role for Novartis, AstraZeneca, Boehringer Ingelheim, Roche, BMS, Ono, Yuhan, Pfizer, Eli Lilly, Janssen, Takeda, MSD; stock ownership in TheraCanVac; royalties from Champions Oncology. CH is an employee of Merck KGaA, Darmstadt, Germany. LSO and PAR are employees of EMD Serono, Billerica, Massachusetts, USA, a business of Merck KGaA, Darmstadt, Germany. JLG reports that the National Cancer Institute (NCI) has a Cooperative Research and Development Agreement (CRADA) with EMD Serono. Resources are provided by this CRADA to the NCI. JLG gets no personal funding from this CRADA but is the co-primary investigator of the CRADA.