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agenus Agenus Announces New Responses for AGEN1181 February 9 , 2021 • 6 total confirmed objective clinical responses in colon , ovarian , and endometrial cancers • No complement - mediated toxicities reported LEXINGTON , Mass . , Feb. 09 , 2021 ( GLOBE NEWSWIRE ) -- Agenus Inc. ( NASDAQ : AGEN ) , an immuno - oncology company with an extensive pipeline of checkpoint antibodies , cell therapies , adjuvants , and vaccines designed to activate immune response to cancers and infections , today announced additional confirmed objective clinical responses from its Phase 1/2 trial of AGEN1181 , its next - generation anti - CTLA - 4 , as monotherapy and in combination with Agenus ' anti - PD - 1 balstilimab . " These are very exciting results which demonstrate the potential of AGEN1181 as an efficacious next - generation CTLA - 4 antibody . AGEN1181 is showing activity in difficult - to - treat tumors without the neuroendocrine or significant liver toxicities commonly observed with the currently - approved CTLA - 4 antibody ipilimumab , " said Dr. Steven O'Day , Chief Medical Officer at Agenus . " The responses seen in patients with ovarian and MSS colorectal cancer are particularly encouraging given the generally low activity seen with immunotherapy in these indications . " The Phase 1 dose escalation trial has had no reports of complement - mediated toxicities . These are severe toxicities associated with first - generation CTLA - 4 antibodies . The trial has also defined the optimal combination dose for AGEN1181 +/- balstilimab . Agenus also presented on the first - ever report of intratumoral Treg depletion with a CTLA - 4 antibody in clinical trials at SITC 2020 . The summary of responses with AGEN1181 alone or in combination with balstilimab are as follows : 1 • CR in PD - L1 ( - ) MSS endometrial cancer patient ( 1181 monotherapy ) • CR by PET in PD - L1 ( - ) MSS endometrial cancer patient ( 1181 + bal ) • PR in PD - L1 ( - ) refractory ovarian cancer patient ( 1181 + bal ) • PR in colorectal cancer patient ( 1181 + bal ) • PR in MSS colorectal cancer patient ( 1181 + bal ) - new confirmed response • PR in ovarian cancer patient ( 1181 + bal ) - new confirmed response AGEN1181 alone and in combination with balstilimab has expanded dosing into colorectal cancer . Phase 2 trials in additional cancer indications are scheduled to commence shortly . About Agenus Agenus is a clinical - stage immuno - oncology company focused on the discovery and development of therapies that engage the body's immune system to fight cancer . The Company's vision is to expand the patient populations benefiting from cancer immunotherapy by pursuing combination approaches that leverage a broad repertoire of antibody therapeutics , adoptive cell therapies ( through its AgenTus Therapeutics subsidiary ) , and proprietary cancer vaccine platforms . The Company is equipped with a suite of antibody discovery platforms and a state - of - the - art GMP manufacturing facility with the capacity to support clinical programs . Agenus is headquartered in Lexington , MA . For more information , please visit www.agenusbio.com and our Twitter handle @agenus_bio . Information that may be important to investors will be routinely posted on our website and Twitter . Forward - Looking Statements This press release contains forward - looking statements that are made pursuant to the safe harbor provisions of the federal securities laws , including statements regarding the therapeutic potential of AGEN1181 as an efficacious next - generation CTLA - 4 antibody and the planned initiation of Phase 2 trials in additional cancer indications . These forward - looking statements are subject to risks and uncertainties that could cause actual results to differ materially . These risks and uncertainties include , among others , the factors described under the Risk Factors section of our most recent Quarterly Report on Form 10 - Q or Annual Report on Form 10 - K filed with the Securities and Exchange Commission . Agenus cautions investors not to place considerable reliance on the forward - looking statements contained in this release . These statements speak only as of the date of this press release , and Agenus undertakes no obligation to update or revise the statements , other than to the extent required by law . All forward - looking statements are expressly qualified in their entirety by this cautionary statement . Contact : Agenus Inc. Caroline Bafundo 212-994-8209 Caroline.Bafundo@agenusbio.com 1 Response evaluation criteria in solid tumors ( RECIST v1.1 )