Janssen-Cilag has shared new data from the Phase Ib/II OrigAMI-1 study at the European Society of Medical Oncology (ESMO) 2024 Congress.

The results show that amivantamab combined with chemotherapy demonstrated promising antitumour activity in patients with RAS/BRAF wild-type (WT) metastatic colorectal cancer (mCRC) who have not previously received anti-epidermal growth factor receptor (EGFR) therapy.

“OrigAMI-1 is the first study to show amivantamab plus chemotherapy may provide clinically meaningful benefits to patients with metastatic colorectal cancer who have not received any EGFR-targeted treatments as their first or second line of therapy,” said Filippo Pietrantonio, Medical Oncologist at Fondazione IRCCS Istituto Nazionale dei Tumori in Milan, Italy, and presenting author. “Notably, we saw 21% of patients proceed to curative intent surgery, showing the promise of amivantamab in patients in this setting.”

The Phase Ib/II OrigAMI-1 study

In the study, patients receiving amivantamab plus chemotherapy were either in their first (26%) or second line (74%) of treatment for mCRC and had not been treated with specific anti-EGFR therapies.

Patients receiving FOLFOX were oxaliplatin-naïve and patients receiving FOLFIRI were irinotecan-naïve. Forty-three patients were treated with amivantamab along with either FOLFOX (20 patients) or FOLFIRI (23 patients). The median follow-up period was 7.3 months.

Patients treated with amivantamab plus chemotherapy achieved an overall response rate (ORR) of 49%, a median duration of response of 7.4 months, and a median progression-free survival of 7.5 months.

Disease control was observed in 88% of patients.1 Clinically meaningful intrahepatic antitumour activity was observed among patients with liver metastases treated with amivantamab plus chemotherapy, demonstrating a significant reduction in liver tumours (ORR of 53%, disease control rate of 93%.

Notably, nine (21%) patients were able to proceed to curative intent surgery due to strong antitumour activity.

“About 20% of patients have metastatic colorectal cancer when they are diagnosed and another 40% have recurrence of their cancer with metastases after initial treatment, making the need for new, targeted treatment options critical,” said Henar Hevia, Senior Director, EMEA Therapeutic Area Lead, Oncology, Johnson & Johnson Innovative Medicine. “The latest results from the OrigAMI-1 study demonstrate the potential of this amivantamab-based combination regimen, with its multi-targeted mechanism of action, to address an important unmet need in metastatic colorectal cancer.”

The company plans to progress to pivotal Phase III registration trials evaluating amivantamab-based regimens as first- and second-line treatment in colorectal cancer.

Diana Spencer, Senior Digital Content Editor, DDW