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LEXEO therapeutics Lexeo Therapeutics Enters Into Agreement to Acquire Mantle Therapeutics and Announces Multiple New Strategic Collaborations to Expand Leadership in Friedreich Ataxia September 22 , 2026 Acquisition of Mantle Therapeutics will add multiple new modalities designed to increase or replace frataxin in the brain Collaborations launched to evaluate gene therapy sequential dosing following treatment with LX2006 and explore cerebellar targeting to optimize outcomes in FA associated neurological disease SUNRISE - FA 2 pivotal study continues enrollment and remains the company's top priority development program ; topline data on track for 2H 2027 Disciplined capital allocation supports these strategic initiatives while maintaining cash runway into 2028 Company to host webcast today at 8:00 AM ET NEW YORK , Sept. 22 , 2026 ( GLOBE NEWSWIRE ) -- Lexeo Therapeutics , Inc. ( Nasdaq : LXEO ) , a clinical stage company focused on reshaping the path of genetic diseases with high unmet need , today announced a series of strategic transactions to expand its presence in Friedreich ataxia ( FA ) , including the signing of a definitive agreement to acquire Mantle Therapeutics Inc. and three new research collaborations supporting cerebellar- targeted development opportunities for frataxin gene therapy . Together , these transactions will simultaneously expand Lexeo's vision and capabilities beyond gene therapy , deepen the company's focus on the multisystem burden of FA , and add multiple therapeutic approaches designed to increase or restore frataxin in the brain . These transactions are being pursued within Lexeo's existing balance sheet capacity , with cash runway guidance unchanged into 2028 and future investment decisions guided by predefined milestones to identify and prioritize the most compelling central nervous system ( CNS ) opportunities . " Our objective is to build the best - in - class therapeutic platform for the treatment of Friedreich ataxia , " said R. Nolan Townsend , Chief Executive Officer of Lexeo Therapeutics . " LX2006 remains our highest priority as the best - in - class treatment for FA cardiomyopathy , and the addition of Mantle's pipeline , combined with new research collaborations will broaden our technology platform with multiple complementary CNS - targeted therapeutic strategies designed to restore frataxin in the brain and further improve outcomes for individuals living with FA . Together , these initiatives will strengthen our leadership position in the disease category while supporting disciplined portfolio advancement and capital allocation . " Acquisition of Mantle Therapeutics Will Establish Lexeo's Multimodal Friedreich Ataxia Platform On September 16th , 2026 , Lexeo entered into an agreement to acquire Mantle Therapeutics Inc. ( " Mantle " ) , a private clinical stage company focused on developing multiple therapies for the treatment of FA . The acquisition will deepen Lexeo's focus on FA and strengthen its capabilities in addressing the neurologic aspects of disease . The acquired portfolio will include : • LX3010 ( MTL - 104 ) : a clinical stage , oral combination therapy designed to increase frataxin expression while addressing mitochondrial function and oxidative stress through complementary mechanisms ( HDAC inhibition and NRf2 ) . Early clinical data includes an approximately 6 - point improvement in mFARS scores at 16 weeks and a mean nine - fold increase in frataxin protein levels from baseline in muscle biopsies across 11 FA patients . • LX3030 ( MTL - 707 ) : a pre - clinical stage oral , tissue - penetrant true small molecule ( sub - 500Da ) designed to increase production of endogenous frataxin in the central nervous system . LX3030 is a third - generation benzamide HDAC inhibitor that builds on published clinical work demonstrating oral benzamide HDACs increase frataxin in FA patients by epigenetic modulation and acetylation of chromatin . Preclinical studies of LX3030 have demonstrated robust increases in frataxin , supporting continued evaluation of LX3030 as a differentiated oral therapy . • LX3050 ( MTL - 501 ) : a pre - clinical stage recombinant human frataxin fused to a proprietary anti - TfR1 Fab , intended to directly replace the deficient frataxin protein and utilize a TfR1 - targeting brain shuttle designed to cross the blood - brain barrier and increase delivery of frataxin to the brain . In vitro studies have demonstrated dose - responsive improvements in measures of mitochondrial function , providing early support for the program's proposed mechanism . • LX3070 ( MTL - 801 ) : a discovery stage ASO Fab conjugate program designed to stabilize FXN mRNA and thereby increase translation of endogenous frataxin protein . The program combines an RNA - targeted mechanism conjugated to a proprietary anti - TfR1 Fab . In vitro studies have demonstrated dose - responsive increases in frataxin . Under the terms of the agreement , Lexeo will pay Mantle shareholders $ 8.3 million in upfront consideration , consisting of a combination of cash and equity . The agreement also provides for up to $ 13.0 million in success - based milestone payments , payable in a combination of cash and equity upon the achievement of future clinical and regulatory milestones , bringing the total potential consideration to $ 21.3 million . Subject to customary closing conditions , the transaction is expected to close in the third quarter of 2026 . Following closing , Lexeo will continue its evaluation of the acquired programs against predefined scientific , clinical , strategic and financial criteria and will prioritize investment in the opportunities demonstrating the strongest potential for clinical patient impact , regulatory success and shareholder value creation . The Company's cash runway guidance into 2028 includes plans to advance one of the acquired programs into clinical development . The Company expects to provide a program prioritization update in early 2027 and submit an IND for its next FA development candidate in 2027 . Together with LX2006 , the expanded portfolio provides Lexeo with the technology to evaluate multiple biologic theses for the treatment of FA in the