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Exhibit 99.1 * Selecta . of Biosciences • Selecta Biosciences Reports Third Quarter 2021 Financial Results and Provides Business Update Established four strategic collaborations to advance next generation therapeutics and maximize the potential of ImmTOR platform Reported topline data from SEL - 399 ( empty AAV8 capsid in combination with ImmTOR ) ; Selecta intends continued expansion of ImmTOR platform across gene therapy pipeline • Continued execution of multiple preclinical programs toward IND • Further strengthened leadership team with the appointment of Kevin Tan as CFO As of September 30 , 2021 , Selecta had approximately $ 140.0 million in cash , cash equivalents , restricted cash and marketable securities which is expected to provide runway into the second quarter of 2023 -- WATERTOWN , Mass . , November 9 , 2021 Selecta Biosciences , Inc. ( NASDAQ : SELB ) , a biotechnology company leveraging its clinically validated ImmTOR ™ platform to develop tolerogenic therapies that selectively mitigate unwanted immune responses , today reported financial results for the third quarter ended September 30 , 2021 and provided a business update . " The third quarter of 2021 was filled with many significant advancements that further validated the value and breadth of our innovative ImmTOR platform , including important milestones across our pipeline and the establishment of numerous collaborations that will continue to propel us forward in the year ahead , ” said Carsten Brunn , Ph.D. , president and chief executive officer of Selecta . “ We recently presented topline data from the empty AAV8 capsid study , SEL - 399 in healthy volunteers . We believe this pioneering proof - of - concept study showed for the first time ImmTOR's potential to address one of the biggest limitations in gene therapy : preventing the formation of anti - AAV8 neutralizing antibodies after ImmTOR treatment with AAVs and enabling re - dosing of life - saving gene therapies . We are excited to build on these exciting findings , which will inform our clinical development strategy and bring hope to those patients suffering from monogenic disease . We continue to prosecute our clinical pipeline , execute value accretive business development with world class partners and add talent and depth to our leadership team . ” Recent Highlights and Anticipated Upcoming Milestones : Enzyme Therapies : SEL - 212 for chronic refractory gout : Enrollment for the Phase 3 DISSOLVE clinical program for the treatment of chronic refractory gout , which was licensed to Sobi , is progressing as planned . о Topline data is expected in the second half of 2022 . ImmTOR with IgA1 protease for IgA nephropathy : Immunoglobulin A nephropathy ( IgAN ) is a leading cause of chronic kidney disease ( CKD ) and renal failure . Current treatments fail to address the root cause of the disease . ° Investigational New Drug , or IND , enabling studies are underway . Selecta expects to file an IND in IgA nephropathy in 2022 and will provide additional updates . Gene Therapies : . First - in - human trial of SEL - 399 : In collaboration with AskBio , Selecta initiated the first - in - human , dose - escalation trial of SEL - 399 , an adeno - associated viral serotype 8 ( AAV8 ) empty vector capsid ( EMC - 101 ) containing no DNA combined with ImmTOR . The key objective was to determine the dose regimen of 1