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May 3 , 2021 Cabaletta BioⓇ Cabaletta Bio Reports Acute Safety Data from the First Dose Cohort in DesCAARTes TM Trial - No dose limiting toxicities ( DLTs ) or clinically relevant adverse events observed in the first dose cohort as of April 30 , 2021 - - Second dose cohort to be initiated after the third patient completes 28 day follow up , absent any DLT - - Acute safety data from the second and third cohorts are anticipated in the third and fourth quarters of 2021 , respectively . Topline data on target engagement in the first cohort are expected in the second half of 2021 - - Company to host conference call today at 8:30 a.m. ET- PHILADELPHIA , May 03 , 2021 ( GLOBE NEWSWIRE ) -- Cabaletta Bio , Inc. ( Nasdaq : CABA ) , a clinical - stage biotechnology company focused on the discovery and development of engineered T cell therapies for patients with B cell - mediated autoimmune diseases , today announced acute safety data from the first dose cohort of the ongoing DesCAARTes ™ Phase 1 clinical trial of DSG3 - CAART for the treatment of patients with mucosal - dominant pemphigus vulgaris ( mPV ) . " We are encouraged by the acute safety profile of DSG3 - CAART in this initial low dose cohort . In the first cohort of three patients dosed with DSG3 - CAART , there were no clinically relevant adverse events , including cytokine release syndrome or neurotoxicity , during the 8- day acute safety window , which we expect is the period with highest probability of observing treatment - related toxicities . In addition , no dose - limiting toxicities or clinically relevant adverse events were observed in the two patients who have completed more than the full 28 - day DLT monitoring period post - infusion , " said David J. Chang , M.D. , Chief Medical Officer of Cabaletta . These safety data were observed with an administered dose of 20 million DSG3 - CAART cells , without preconditioning and in the presence of circulating anti- DSG3 antibodies ; DSG3 - CAART was detected at low levels via quantitative polymerase chain reaction in both patients who have been evaluated and completed the 28 - day DLT period . The third patient is scheduled to be evaluated for presence of DSG3 - CAART after the 28 - day follow - up period . " The pace of the clinical trial is accelerating with the ongoing enrollment of patients and engagement of additional clinical sites . We believe these initial safety data represent an important step towards achieving our goal to offer a therapy that may provide deep and durable responses , and potentially cures , for patients in the pemphigus community , ” said Dr. Chang . The DesCAARTes ™ trial is currently enrolling patients in the second cohort at a treatment dose of 100 million DSG3 - CAART cells . Infusions are planned to initiate following the third