Journal of Clinical Oncology | Phase II Study of the EGFR-MET Bispecific Antibody Amivantamab in Previously Treated Head and Neck Squamous Cell Carcinoma

This study provides a novel and effective treatment option for patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) who have progressed after immunotherapy and chemotherapy, supporting further exploration of dual inhibition strategies targeting EGFR and MET in precision oncology for solid tumors.

 

Literature Overview

The article titled 'Amivantamab in Recurrent/Metastatic Head and Neck Squamous Cell Cancer After Checkpoint Inhibitor and Chemotherapy: Pivotal Results From the Phase Ib/II OrigAMI-4 Study,' published in the 'Journal of Clinical Oncology,' systematically investigates the antitumor activity and safety of subcutaneously administered EGFR-MET bispecific antibody amivantamab in patients with non-HPV-related recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) who have failed prior PD-(L)1 inhibitor and platinum-based chemotherapy. Based on full population data from cohort 1 of the phase II trial, this study presents key efficacy endpoints assessed by independent central blinded review (BICR), providing high-level evidence for subsequent treatment strategies in this patient population.

Background Knowledge

Head and neck squamous cell carcinoma (HNSCC) accounts for nearly 890,000 new cases annually worldwide, with HPV-negative tumors frequently exhibiting low p16 expression and poor prognosis. In these tumors, EGFR and MET pathways are commonly co-expressed, driving tumor proliferation, metastasis, and immune escape, making them important therapeutic targets. Currently, for R/M HNSCC patients progressing after first-line immunotherapy and chemotherapy, standard treatments such as paclitaxel or cetuximab achieve objective response rates (ORR) of only 21%–24%, with complete responses (CR) being rare and median overall survival (OS) less than one year, highlighting a significant unmet clinical need. Although EGFR-targeted monoclonal antibodies (e.g., cetuximab) are approved, resistance often arises through bypass activation of the MET pathway, limiting efficacy. Therefore, the bispecific antibody amivantamab, which simultaneously targets EGFR and MET, theoretically overcomes the limitations of single-target inhibition and may provide more durable antitumor responses. This study was designed to test this mechanistic hypothesis and validate the clinical value of amivantamab in this heavily pretreated population.

 

 

Research Methods and Experiments

This was an open-label, multicenter phase Ib/II clinical trial (OrigAMI-4, NCT06385080). Cohort 1 enrolled 102 adult patients with histologically confirmed non-HPV-related R/M HNSCC who had previously received anti–PD-(L)1 inhibitors and platinum-based chemotherapy but had not received prior anti-EGFR therapy. The primary endpoint was objective response rate (ORR) per RECIST v1.1 assessed by independent blinded central review (BICR). Secondary endpoints included duration of response (DoR), progression-free survival (PFS), overall survival (OS), and safety. Amivantamab was administered subcutaneously every three weeks at a weight-based dose. Efficacy was monitored using standard imaging assessments (every 6 weeks), and adverse events were recorded using CTCAE v5.0 criteria.

Key Conclusions and Perspectives

• BICR-assessed ORR reached 42% (95% CI: 32–52), significantly higher than the historical control range of 21%–24%; this suggests that in clinical trial design for rigorously selected refractory populations, higher target ORR thresholds should be considered as a benchmark for efficacy.
• The complete response (CR) rate was as high as 15%, far exceeding the 1% seen with cetuximab monotherapy; this indicates deep antitumor activity with amivantamab, potentially offering long-term disease control or even potential cures for some patients, warranting further investigation into its role as a transformative therapy.
• Median overall survival (OS) was 12.5 months, with a 12-month OS rate of 54%; these results demonstrate that amivantamab substantially improves survival in a population with otherwise poor prognosis, and should serve as a benchmark for future phase III or real-world studies.
• Median duration of response (DoR) was not reached, with 56% of responses lasting ≥6 months; this indicates that dual EGFR/MET targeting induces durable responses, suggesting resistance mechanisms may differ from those seen with single-target inhibition. Future studies should focus on dynamic ctDNA monitoring to elucidate resistance mechanisms.
• Safety was manageable, with a 60% incidence of grade ≥3 treatment-related adverse events and only an 8% treatment discontinuation rate due to toxicity; this shows that the subcutaneous formulation of amivantamab is well tolerated, supporting long-term administration in outpatient settings and improving patient adherence.

Research Significance and Prospects

This study establishes amivantamab as one of the new standards of care in second-line treatment for R/M HNSCC, particularly offering a precision medicine approach for patients with activated EGFR/MET pathways. Its subcutaneous administration (<10 minutes) greatly enhances convenience compared to traditional intravenous infusions (~1 hour), thereby improving patient quality of life.

From a drug development perspective, this trial provides a successful example of bispecific antibodies in solid tumors, encouraging further clinical development of dual-targeting agents against co-activated pathways. Future exploration of combination regimens—such as ongoing phase III OrigAMI-5 trials evaluating amivantamab with immunotherapy or chemotherapy—may advance treatment lines and improve cure rates.

In terms of clinical monitoring, exploratory ctDNA analyses in this study highlight the potential for molecular-level response assessment. Future efforts should develop dynamic risk stratification models based on ctDNA to guide personalized treatment decisions.

 

 

Conclusion

This study represents a significant breakthrough in the treatment landscape of recurrent and metastatic head and neck squamous cell carcinoma. As an EGFR-MET bispecific antibody, amivantamab demonstrates unprecedented antitumor activity in patients who have failed both immunotherapy and chemotherapy, achieving an ORR of 42% and a median OS of 12.5 months—markedly surpassing current standard therapies. These results not only offer new hope to patients but also validate the scientific rationale for dual blockade of EGFR and MET pathways to overcome resistance. From bench to bedside, this success reflects the evolution of targeted therapy from single-target inhibition toward coordinated multi-pathway suppression. In the future, integrating genomic testing to identify optimal beneficiaries, along with the development of more convenient subcutaneous formulations, may position amivantamab as a cornerstone of precision medicine in HNSCC. Moreover, its success in head and neck cancer provides valuable insights for treating other EGFR/MET co-expressing tumors—such as non-small cell lung cancer and gastric cancer—and accelerates the broader application of bispecific antibodies in solid tumor oncology.

 

Barbara Burtness, Ari J Rosenberg, Benoit Calderon, Kevin J Harrington, and for the OrigAMI-4 Cohort 1 Investigators. Amivantamab in Recurrent/Metastatic Head and Neck Squamous Cell Cancer After Checkpoint Inhibitor and Chemotherapy: Pivotal Results From the Phase Ib/II OrigAMI-4 Study. Journal of Clinical Oncology.