An Exploratory Study of ABT-806, a Tumor-Specific Anti-EGFR Antibody, in Subjects with Recurrent or Metastatic Head and Neck and Other Squamous Cell Carcinomas
6 affiliations
- 1Medical Oncology, Austin Hospital, 145 Studley Road, Heidelberg, Melbourne, VIC 3084, Australia
- 2Tumor Targeting Program, Olivia Newton-John Cancer Research Institute, Melbourne, VIC 3084, Australia
- 3School of Cancer Medicine, La Trobe University, Melbourne, VIC 3084, Australia
- 4Oncology Discovery, AbbVie Inc., North Chicago, IL 60064, USA
- 5Department of Molecular Imaging and Therapy, Austin Health, Melbourne, VIC 3084, Australia
- 6Faculty of Medicine, Melbourne University, Melbourne, VIC 3010, Australia
Abstract
Introduction: Despite their benefit, current anti-EGFR therapies are limited by narrow efficacy profiles due to dose-limiting toxicities. This phase 2 open-label study evaluated the efficacy and safety of ABT-806, an EGFR-targeting antibody that is tumor specific, in patients with advanced EGFR-expressing tumors including head and neck cancers (H&NC) and squamous cell carcinoma (SCC) of other sites. Methods: Patients with advanced H&NC (cohort A) or SCC of other sites (cohort B) were enrolled in the study. ABT-806 was administered as monotherapy at a dose of 24 mg/kg intravenously using a twice weekly dosing schedule until unacceptable toxicity and/or evidence of disease progression. Adverse events (AEs) were graded using the National Cancer Institute Common Terminology Criteria for Adverse Events v4.0; tumor response was assessed using the Response Evaluation criteria in Solid Tumors v1.1. EGFR status was assessed with mAb806 and EGFRvIII immunohistochemistry and correlated with outcomes. Results: ABT-806 was well tolerated with no grade 3+ treatment-related AEs. Disease stabilization was observed in two patients (14%) and for a median duration of 19.5 weeks. This included one patient from cohort A and one patient from cohort B. Progression-free survival and overall survival was not significantly different between the two cohorts. Conclusions: Although clinical activity was limited in this small, heavily pre-treated, and biomarker-unselected population, ABT-806 demonstrated an excellent safety profile with minimal classical EGFR-related toxicity. These findings support the development of more tumor-specific EGFR antibodies for use, particularly in combinatorial regimens.
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BibTeX
@article{gan2026exploratory,
title = {{An Exploratory Study of ABT-806, a Tumor-Specific Anti-EGFR Antibody, in Subjects with Recurrent or Metastatic Head and Neck and Other Squamous Cell Carcinomas}},
author = {Hui K. Gan and Sagun Parakh and Malaka Ameratunga and Anis Hamid and George Iatropoulos and Michelle Beecher and Diana Cao and Kerryn Westcott and Jaren Caine and Jodie Palmer and Edward B. Reilly and Fiona E. Scott and Andrew M. Scott},
journal = {Cancers},
year = {2026},
month = oct,
doi = {10.3390/cancers18203313},
url = {https://www.mdpi.com/2072-6694/18/20/3313},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - An Exploratory Study of ABT-806, a Tumor-Specific Anti-EGFR Antibody, in Subjects with Recurrent or Metastatic Head and Neck and Other Squamous Cell Carcinomas
AU - Hui K. Gan
AU - Sagun Parakh
AU - Malaka Ameratunga
AU - Anis Hamid
AU - George Iatropoulos
AU - Michelle Beecher
AU - Diana Cao
AU - Kerryn Westcott
AU - Jaren Caine
AU - Jodie Palmer
AU - Edward B. Reilly
AU - Fiona E. Scott
AU - Andrew M. Scott
PY - 2026
DA - 2026/10/01
JO - Cancers
DO - 10.3390/cancers18203313
UR - https://www.mdpi.com/2072-6694/18/20/3313
AB - Introduction: Despite their benefit, current anti-EGFR therapies are limited by narrow efficacy profiles due to dose-limiting toxicities. This phase 2 open-label study evaluated the efficacy and safety of ABT-806, an EGFR-targeting antibody that is tumor specific, in patients with advanced EGFR-expressing tumors including head and neck cancers (H&NC) and squamous cell carcinoma (SCC) of other sites. Methods: Patients with advanced H&NC (cohort A) or SCC of other sites (cohort B) were enrolled in the study. ABT-806 was administered as monotherapy at a dose of 24 mg/kg intravenously using a twice weekly dosing schedule until unacceptable toxicity and/or evidence of disease progression. Adverse events (AEs) were graded using the National Cancer Institute Common Terminology Criteria for Adverse Events v4.0; tumor response was assessed using the Response Evaluation criteria in Solid Tumors v1.1. EGFR status was assessed with mAb806 and EGFRvIII immunohistochemistry and correlated with outcomes. Results: ABT-806 was well tolerated with no grade 3+ treatment-related AEs. Disease stabilization was observed in two patients (14%) and for a median duration of 19.5 weeks. This included one patient from cohort A and one patient from cohort B. Progression-free survival and overall survival was not significantly different between the two cohorts. Conclusions: Although clinical activity was limited in this small, heavily pre-treated, and biomarker-unselected population, ABT-806 demonstrated an excellent safety profile with minimal classical EGFR-related toxicity. These findings support the development of more tumor-specific EGFR antibodies for use, particularly in combinatorial regimens.
SN - 2072-6694
ER -