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Agenus Corporate Update and First Quarter 2021 Financial Report • Balstilimab BLA submitted to FDA for recurrent / metastatic cervical cancer • Balstilimab and AGEN2373 data to be presented at ASCO • iNKT cell therapy Phase 1 initiated in cancer EXHIBIT 99.1 LEXINGTON , Mass . , May 06 , 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 provided a corporate update and reported financial results for the first quarter of 2021 . " We have delivered on multiple key initiatives since our last update and expect to achieve additional impactful milestones during the remainder of the second quarter and the rest of 2021 , " said Garo Armen , PhD , Chief Executive Officer of Agenus . " Among important developments are the continuing clinical responses we are seeing with AGEN1181 . We intend to advance AGEN1181 in combination with balstilimab in cancers for which current immunotherapies have shown no activity given AGEN1181's positive clinical responses in these tumors . Treating these cancers successfully will be of substantial value to patients while potentially representing large commercial opportunities for Agenus . " Balstilimab ( anti - PD - 1 ) : BLA submitted to U.S. FDA for recurrent / metastatic cervical cancer • A Biologics License Application ( BLA ) was submitted to the U.S. Food and Drug Administration ( FDA ) for the accelerated approval of balstilimab for the treatment of patients with recurrent or metastatic cervical cancer with disease progression on or after chemotherapy . • The submission was based on an update to data presented at the European Society for Medical Oncology ( ESMO ) Virtual Congress 2020 and published in an Oncogene editorial . This updated dataset includes maturation of late patient responses , with the overall data showing response rates of 20 % in PD - L1 positive tumors , 15 % in all tumors ( PD - L1 positive and negative ) , and a median duration of response of 15.4 months . • Data demonstrating that balstilimab is a potentially differentiated anti - PD - 1 antibody will be presented at the 2021 American Society for Clinical Oncology ( ASCO ) Annual Meeting from June 4 – 8 , 2021 . - • Discussions with the FDA regarding accelerated BLA filing for balstilimab plus zalifrelimab are ongoing ; additional guidance and updated response rate data will be provided upon the FDA acceptance of the balstilimab monotherapy BLA . AGEN1181 ( anti - CTLA - 4 ) : Data demonstrate continued strong activity , including in tumors unresponsive to immunotherapy , as presented at AACR 2021 • At the American Association for Cancer Research ( AACR ) annual meeting , a new partial response with AGEN1181 monotherapy was reported in the first and only melanoma patient treated to date , as well as a new conversion to complete response with AGEN1181 plus balstilimab in an ovarian cancer patient . • Continued clinical activity in patients with biomarkers which indicate a poor prognosis with approved immunotherapies , including patients with microsatellite stable ( MSS ) tumors and melanoma , endometrial , and ovarian cancer with the low- affinity FcyRIIIA allele . No immune - mediated hypophysitis , pneumonitis , or hepatitis were reported . • As of AACR 2021 , a total of seven confirmed objective responses were achieved in a Phase 1/2 trial of AGEN1181 in solid tumors out of 52 evaluable patients : 2 confirmed responses among 21 treated with monotherapy , and 5 confirmed responses among 31 treated with AGEN1181 in combination with balstilimab . • Phase 2 trial in colorectal cancer was initiated ; registrational trials are targeted to commence in 2021 with a focus on indications enabling a rapid path to BLA submission . Further data updates expected later this year . AGEN1777 ( anti - TIGIT bispecific ) : Phase 1 anticipated 2021 • IND submission is planned for the current quarter . • Phase 1 study is expected to commence in the third quarter . Intelligent cell platform : Phase 1 study ongoing with iNKT cell therapy in patients with cancer and ARDS secondary to COVID - 19 • Phase 1 trial in hematologic cancers was initiated ; expansion into solid tumors is expected this year . • Preliminary Phase 1 data for acute respiratory distress syndrome ( ARDS ) secondary to COVID - 19 suggest iNKTS ( invariant natural killer T cells ) can be dosed without adverse events attributable to the therapy and may demonstrate early signals of activity . Dose escalation is expected to be completed this year with data readouts to be presented at upcoming conferences .