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sesen bio Sesen Bio Reports Third Quarter 2021 Financial Results and Business Update November 8 , 2021 Participated in productive CMC Type A Meeting with the FDA Maintained strong balance sheet with $ 175M in cash and cash equivalents as of September 30 , 2021 CAMBRIDGE , Mass .-- ( BUSINESS WIRE ) -- Nov . 8 , 2021-- Sesen Bio ( Nasdaq : SESN ) , a late - stage clinical company developing targeted fusion protein therapeutics for the treatment of patients with cancer , today reported operating results for the third quarter ended September 30 , 2021. During the quarter , the Company continued to work on its path forward to address chemistry , manufacturing , and controls ( CMC ) and clinical issues identified by the US Food & Drug Administration ( FDA ) in its Complete Response Letter ( CRL ) regarding the Company's Biologics License Application ( BLA ) for the Company's lead program , Vicineum ™ for the treatment of BCG - unresponsive non - muscle invasive bladder cancer ( NMIBC ) . " Our team is making progress in advancing our dialogue with the FDA as we work toward potential resolution of the issues raised in the CRL for Vicineum , as demonstrated by our recent CMC Type A Meeting with the agency , " said Dr. Thomas Cannell , president and chief executive officer of Sesen Bio . " We remain dedicated to saving and improving the lives of patients , and we look forward to continuing to work collaboratively with the FDA in our upcoming Clinical Type A Meeting , expected later this year , to carry our mission into the next stage of the regulatory process and beyond . " Regulatory Update US : • On August 13 , 2021 , Sesen Bio announced that it had received a CRL from the FDA regarding its BLA for the Company's lead program , Vicineum for the treatment of BCG - unresponsive NMIBC . The FDA determined that it could not approve the BLA for Vicineum in its present form and provided recommendations specific to additional clinical / statistical data and analyses , in addition to CMC issues pertaining to a recent pre - approval inspection and product quality . • On October 29 , 2021 , Sesen Bio participated in a productive CMC Type A Meeting with the FDA ( CMC Type A Meeting ) . The purpose of the meeting was to discuss questions related to CMC raised in the CRL . During the meeting , the Company and the FDA reviewed issues related to CMC to be further discussed during the review of the BLA for Vicineum upon potential resubmission . Key takeaways from the meeting include : o The FDA confirmed that Vicineum manufactured using the proposed commercial process is comparable to Vicineum used in prior clinical trials . o The FDA confirmed that Sesen Bio can utilize Vicineum manufactured during process validation for any potential future clinical trials needed to address issues raised in the CRL , and that these potential trials can proceed while addressing CMC issues . o The Company believes it has a clear understanding of the path forward regarding CMC for resubmission of the BLA . Sesen Bio is preparing for a separate Type A Meeting to discuss the recommendations specific to additional clinical / statistical data and analyses that the FDA raised in the CRL ( Clinical Type A Meeting ) , which the Company expects to occur later this year . As previously disclosed , the Company anticipates needing to conduct an additional clinical trial with 90-100 patients , and will provide further guidance after the Clinical Type A Meeting . The Company intends to use the information from the CMC Type A Meeting and the Clinical Type A Meeting to synchronize the regulatory reviews of Vicineum for the treatment of BCG - unresponsive NMIBC in the US and the European Union . European Union : • On August 20 , 2021 , Sesen Bio withdrew its marketing authorization application ( MAA ) to the European Medicines Agency ( EMA ) for VysyneumTM for the treatment of BCG - unresponsive NMIBC . Given that certain components in the EMA's review are interrelated with elements of the FDA's decision to issue a CRL for Vicineum , the Company decided to