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KEZAR LIFE SCIENCES Kezar Life Sciences Reports Second Quarter Financial Results and Provides Business Updates August 12 , 2021 • KZR - 616 MISSION Phase 1b study results support continued development for multiple immune mediated diseases Investigational new drug ( IND ) application filed for first - in - class protein secretion inhibitor , KZR - 261 . • Expertise in autoimmune drug development added with appointment of Micki Klearman , MD , to Board of Directors and creation of Clinical Advisory Committee SOUTH SAN FRANCISCO , Calif .-- ( BUSINESS WIRE ) -- Kezar Life Sciences , Inc. , ( Nasdaq : KZR ) , a clinical - stage biotechnology company discovering and developing breakthrough treatments for immune - mediated and oncologic disorders , today announced its second quarter 2021 financial results and corporate highlights . " We were pleased this quarter to share the final data update from our completed Phase 1b portion of the MISSION study , building on the positive safety , tolerability and early efficacy profile of KZR - 616 . I commend the entire team at Kezar on another quarter of outstanding execution across both of our programs and look forward to providing meaningful updates from both before the end of the year , " said John Fowler , Kezar's Co - founder and Chief Executive Officer . " We are also pleased to announce that Kezar recently submitted an IND application to the FDA for KZR - 261 , our first - in - class protein secretion inhibitor . Like the platform potential we see for KZR - 616 in autoimmunity , we believe KZR - 261 could have broad potential across the oncology landscape . We look forward to sharing more about our planned Phase 1 trial design and the potential of our protein secretion drug discovery platform in the coming months . " Clinical Highlights & Updates KZR - 616 : Selective Immunoproteasome Inhibitor MISSION - Phase 2 clinical trial in patients with lupus nephritis ( LN ) ( NCT03393013 ) At the European Congress of Rheumatology ( EULAR 2021 ) in June , Kezar presented final clinical data from the completed Phase 1b dose escalation portion of the MISSION study in 47 patients with systemic lupus erythematous , including two patients with active proliferative LN . KZR - 616 demonstrated improvement across all exploratory efficacy measures and was well - tolerated up to 75 mg subcutaneously once weekly for 13 weeks . In the two patients with LN , improvements in renal function correlated with reductions in a key biomarker of kidney inflammation , uCD163 . • The safety and tolerability profile observed with KZR - 616 was consistent with previously reported data and supports treatment for chronic use . No new safety or tolerability signals were observed from previously reported data . • These data support the development of KZR - 616 in multiple immune - mediated diseases . • Doses being investigated in the Phase 2 clinical trials are 60 mg ( MISSION Phase 2 in LN ) and 45 mg ( PRESIDIO Phase 2 in dermatomyositis and polymyositis ) with weekly subcutaneous dosing . • The amended Phase 2 open - label portion of the MISSION trial in patients with active , proliferative LN opened for enrollment in August 2020 and is actively recruiting . The primary efficacy endpoint for the trial is the proportion of patients achieving a renal response measured by a 50 % or greater reduction in urine protein to creatinine ratio ( UPCR ) at six months . • Kezar reiterates prior guidance and expects interim data to be reported in Q4 2021 , and topline data are expected in the first half of 2022 . PRESIDIO - Phase 2 clinical trial in patients with dermatomyositis ( DM ) and polymyositis ( PM ) ( NCT04033926 ) • The PRESIDIO Phase 2 , placebo controlled cross - over trial of KZR - 616 in DM and PM is actively enrolling . Additionally , a 12 - month open - label extension study is open to patients completing the 32 - week placebo - controlled trial ( NCT04628936 ) . o Topline data are expected in the first half of 2022 . KZR - 261 : Protein Secretion Inhibitor • KZR - 261 is a first - in - class protein secretion inhibitor that targets the Sec61 translocon and has demonstrated broad anti - tumor activity in preclinical models of both solid and hematologic malignancies . • Kezar submitted an investigational new drug ( IND ) application for KZR - 261 to the U.S. Food and Drug Administration ( FDA ) in August 2021. The company plans to initiate a Phase 1 clinical trial of KZR - 261 , which will assess safety , tolerability and preliminary tumor activity of KZR - 261 in solid tumors . o At the American Association of Cancer Research ( AACR ) 2021 Virtual Annual Meeting in April , Kezar presented preclinical data on its novel small molecule inhibitors of the Sec61 translocon . These data support the therapeutic potential of inhibiting Sec61 and the protein secretion pathway as a way to generate novel therapies to treat