Benzinga | Dec 1, 2020 08:12AM EST

Agenus Reports Launch Of Phase 2 Trial Expansion In Colon Cancer For AGEN1181 In Combo With Balstilimab

Agenus Inc. (NASDAQ:AGEN), an immuno-oncology company with a broad pipeline which includes checkpoint antibodies, cell therapies, adjuvants, and vaccines designed to activate immune response to cancers and infections, today announced the expansion of a Phase 2 trial into colon cancer based on a new objective clinical response in a colorectal cancer patient in addition to a significant tumor reduction of 27% and biomarker reduction observed in a patient with MSS colon cancer.

With this recent response in colon cancer, AGEN1181 +/- balstilimab (anti-PD-1) has reported 4 clinical responses plus a significant tumor reduction of more than 27% in a fifth patient. In addition, 19 patients have achieved disease stabilization out of 41 patients treated in what was designed as a dose escalation study.

Recently, Agenus also presented on the first-ever report of intratumoral Treg depletion with a CTLA-4 antibody in clinical trials. The summary of responses achieved with AGEN1181 alone or in combination with balstilimab are as follows:

* CR in PD-L1(-) MSS endometrial cancer patient (1181 monotherapy)

* CR in PD-L1(-) MSS endometrial cancer patient (1181 + bali)

* PR in a colorectal cancer patient (1181 + bali)

* PR in PD-L1(-) refractory ovarian cancer patient (rescued with 1181 + bali) -- previous stable disease for 66 weeks with 1181 monotherapy

* Major tumor reduction (27%) in MSS colorectal cancer with remarkable CEA biomarker reduction from 298 to 2 (1181 + bali)

In the phase 1 trial of AGEN1181, clinical benefit and responses have been seen in patients with polymorphism in FcyRIIIA alleles who are not responsive to first-generation CTLA-4 antibodies.

The Phase 2, open-label, multicenter study will focus primarily on colorectal cancer and select solid tumors, such as lung cancer and melanoma.

"These early data are very exciting, particularly in aggressive tumors that have traditionally been unresponsive to immune therapies, like colorectal cancer," said Dr. Joseph Grossman, expert in gastrointestinal cancers and the Head of Exploratory Medicine at Agenus. "AGEN1181 has potential to not only broaden the population of responders to CPIs, but also to reach tumors traditionally considered "cold" or unresponsive to immune therapies. I am excited to see the potential broadened benefit of our next-generation anti-CTLA-4's design, particularly its Fc-enhancement, and the validation of Agenus' incredible R&D capabilities."

Dr. Joseph Grossman recently joined Agenus as head of exploratory medicine from Harvard Medical School, where he was an instructor in medicine, and Beth Israel Deaconess Medical Center, where he served as an attending physician in GI oncology. He completed his residency and fellowship in hematology oncology at Beth Israel Deaconess Medical Center. He holds a postbaccalaureate certificate in premedical sciences from Columbia University in the City of New York and an MD from Brown Medical School.