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Selecta Biosciences Reports Second Quarter 2021 Financial Results and Provides Business Update Exhibit 99.1 • • IND filing for wholly owned gene therapy program , SEL - 302 ( MMA - 101 , in combination with ImmTOR ) in methylmalonic acidemia ( MMA ) expected during the third quarter of 2021 ; Manufacturing issue has been resolved , with a new completed lot undergoing final release testing SEL - 399 ( empty AAV8 capsid with ImmTOR ) study on track with topline data expected in the fourth quarter of 2021 Selecta achieved $ 3 million milestone payment from Sarepta Therapeutics related to successfully meeting the criteria for a preclinical study As of June 30 , 2021 , Selecta had approximately $ 151.5 million in cash , cash equivalents , and marketable securities which is expected to provide runway into the third quarter of 2023 WATERTOWN , Mass . , August 12 , 2021 ( GLOBE NEWSWIRE ) -- 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 second quarter ended June 30 , 2021 and provided a business update . " We are very pleased about our continued progress across all aspects of the company , " said Carsten Brunn , Ph.D. , president , and chief executive officer of Selecta . " Building on our ongoing empty AAV8 capsid study , we are rapidly advancing our two proprietary gene therapy programs into the clinic and as we enter a critical inflection point in development , we are honored to have gene therapy pioneer , Jude Samulski , Ph.D. , join as a special advisor . The recently published preclinical data is encouraging and further supports the advancement of our lead candidate in methylmalonic acidemia ( MMA ) , SEL - 302 . We will build on this momentum and expect to file an IND in MMA during the third quarter of 2021 , bringing us one step closer to addressing immunogenicity constraints in AAV - driven gene therapy and ultimately , providing patients with potentially transformative treatment options . Additionally , we are steadily executing across our enzyme and autoimmune development program . We have a well - defined work plan ahead of us and the financial resources to maximize the value of our innovative ImmTOR platform . " 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 . Investigational New Drug , or IND , enabling studies are underway for a novel therapeutic approach that combines ImmTOR with an enzyme , IgA1 protease for the treatment of IgA nephropathy . ° Selecta expects to file an IND in IgA nephropathy in 2022 and will provide additional updates later in the year . 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 trial aims to determine the dose regimen of ImmTOR to mitigate the formation of antibodies to AAV8 capsids used in gene therapies . Topline data is expected in the fourth quarter of 2021 . ° SEL - 302 for methylmalonic acidemia ( MMA ) : Selecta announced publication in the journal Molecular Therapy Methods & Clinical Development demonstrating that ImmTOR enhances transgene expression after both initial and repeat dosing of AAV in a mouse model of MMA . The publication further validates use of ImmTOR in Selecta's gene therapy pipeline , including its lead candidate , SEL - 302 ( MMA - 101 in combination 1