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KINIKSA Kiniksa Reports Second Quarter 2021 Financial Results and Recent Corporate and Portfolio Activity August 3 , 2021 Q2 2021 ARCALYSTⓇ ( rilonacept ) net revenue of $ 7.7 million with greater than 100 prescribing physicians - - Phase 3 data from mavrilimumab clinical trial in COVID - 19 - related ARDS on - track for Q1 2022 ; new Phase 2 data demonstrate persistent clinical effect through Day 90 - - Initiation of KPL - 404 Phase 2 proof - of - concept clinical trial expected in Q4 2021 - - Conference call and webcast scheduled for 8:30 a.m. ET today - HAMILTON , Bermuda , Aug. 03 , 2021 ( GLOBE NEWSWIRE ) -- Kiniksa Pharmaceuticals , Ltd. ( Nasdaq : KNSA ) ( " Kiniksa " ) , a biopharmaceutical company with a portfolio of assets designed to modulate immunological pathways across a spectrum of diseases , today reported second quarter 2021 financial results and recent corporate and portfolio activity . " Our commercial team is doing a superb job with the launch of ARCALYST in recurrent pericarditis , " said Sanj K. Patel , Chief Executive Officer and Chairman of the Board of Kiniksa . " Feedback received from physicians and patients highlights the transformational potential of ARCALYST for patients suffering from recurrent pericarditis . We have seen strong uptake and look forward to using this momentum to accelerate broader adoption across this underserved population . " " We are executing on the development of our clinical - stage pipeline , " said John F. Paolini , MD , PhD , Chief Medical Officer of Kiniksa . " The potential broad utility of mavrilimumab across multiple indications is increasingly promising , and we expect data from our Phase 3 clinical trial in COVID- 19 - related ARDS in the first quarter of 2022. We are enrolling a Phase 2b clinical trial of vixarelimab in prurigo nodularis and believe vixarelimab has the potential to make a meaningful impact on these patients ' lives by addressing both the pruritus and the skin nodules associated with this devastating disease . KPL - 404 , our anti - CD40 program , has potential across a range of autoimmune diseases , and we plan to initiate a Phase 2 proof- of - concept clinical trial in rheumatoid arthritis in the fourth quarter of this year . " Portfolio Activity ARCALYST ( IL - 1a and IL - 1ẞ cytokine trap ) • ARCALYST net revenue in the second quarter of 2021 was $ 7.7 million . • The second quarter of 2021 represented Kiniksa's first quarter of ARCALYST sales . ARCALYST became commercially available through Kiniksa on April 1st , 2021 . • Greater than 100 physicians who did not participate in Phase 3 RHAPSODY prescribed ARCALYST to at least one recurrent pericarditis patient . • Greater than 65 % of all recurrent pericarditis enrollments came from physicians practicing outside of the 12 Phase 3 RHAPSODY clinical trial sites in the U.S. • Greater than 90 % of completed new patient enrollment cases were approved for coverage under the payer medical exceptions process . • Kiniksa continues to expect that the majority of payers will establish coverage policies within six months and that almost all payers will update their coverage policies within a year from launch . • Kiniksa OneConnect TM provided access , initiation and ongoing support for existing ARCALYST cryopyrin - associated periodic syndromes ( CAPS ) and deficiency of IL - 1 receptor antagonist ( DIRA ) patients transitioning to Kiniksa product as well as new ARCALYST patients for all approved indications . Mavrilimumab ( monoclonal antibody inhibitor targeting GM - CSFRα ) • Kiniksa's interactions with the U.S. Food and Drug Administration ( FDA ) resulted in defined paths for Phase 3 development of mavrilimumab in COVID - 19 - related acute respiratory distress syndrome ( ARDS ) and in giant cell arteritis ( GCA ) . • Kiniksa today announced additional data from the Phase 2 portion of the Phase 2/3 clinical trial of mavrilimumab in patients with severe COVID - 19 - related ARDS . • Follow - up overall survival data from the cohort of non - mechanically ventilated patients through Day 90 demonstrated persistent clinical effect , confirming and extending the previously - reported Day 29 data . • Day 29 data from the cohort of mechanically - ventilated patients did not show a reduction in death .