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Agenus Provides Update on Balstilimab Development Exhibit 99.1 Company voluntarily withdraws BLA at FDA's recommendation following full approval of pembrolizumab , which came four months earlier than FDA goal date Balstilimab achieved trial endpoints with 20 % response rates in PD - L1 positive patients , versus 14 % reported in pembrolizumab’s label ; Agenus successfully completed 3 FDA pre - approval inspections for the PDUFA date of Dec. 16 , 2021 Agenus plans to launch expanded access programs to give patients access to balstilimab in several countries , including the US Agenus will discontinue its ongoing confirmatory trial ( BRAVA ) in this population , which is expected to reduce R & D expenses by over $ 100M _ Accelerated development of balstilimab in combination with AGEN1181 will be launched in multiple tumor types ; clinical update at SITC LEXINGTON , Mass . , October 22 , 2021 / GLOBENEWSWIRE / Agenus ( 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 a strategic decision to withdraw its Biologics License Application ( BLA ) for balstilimab , its PD - 1 inhibitor . The decision to withdraw the BLA does not change the development plans for balstilimab combinations . Following the full approval of pembrolizumab , announced four months earlier than the FDA goal date , the U.S. Food and Drug Administration ( FDA ) no longer considered it appropriate to review the BLA for accelerated approval and recommended Agenus withdraw . The BLA submission for balstilimab received Fast Track and Priority Review designation from the FDA , with a target action date of December 16 , 2021. As part of the BLA review process , Agenus successfully completed 3 FDA inspections with no cited issues , concerns , or Form - 483s . As previously reported , in the largest single - arm trial to date in this population ( 140 evaluable patients ) , balstilimab demonstrated objective responses in both PD - L1 positive and negative patients , with an objective response rate ( ORR ) of 20 % and 8 % respectively¹ . Pembrolizumab has demonstrated an ORR of 14 % and 0 % in PD - L1 positive and negative patients respectively , which led to its accelerated approval in 2018. Balstilimab has shown superior killing of PD - L1 negative tumors compared to other anti PD - 1 therapies , including pembrolizumab , suggesting a broader mechanism consistent with balstilimab's clinical activity in both PD - L1 positive and negative cervical cancer² .