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leaptherapeutics Leap Therapeutics Presents Updated Positive Data from the DisTinGuish Study of DKN - 01 Plus Tislelizumab at the ESMO Congress September 16 , 2021 - DKN - 01 plus tislelizumab and chemotherapy demonstrated compelling activity in first - line patients with gastric or gastroesophageal junction cancer - Additional data presented today showed responses to treatment are independent of PD - L1 expression , with 79 % ORR in patients with PD - L1 low ( CPS < 5 ) tumors - Company to host conference call on Friday , September 17 , 2021 at 8:00 a.m. ET CAMBRIDGE , Mass . , Sept. 16 , 2021 / PRNewswire / -- Leap Therapeutics , Inc. ( Nasdaq : LPTX ) , a biotechnology company focused on developing targeted and immuno - oncology therapeutics , today announced the presentation of updated positive data from the first - line cohort of the Distinguish study , a Phase 2a clinical trial evaluating Leap's anti - Dickkopf - 1 ( DKK1 ) antibody , DKN - 01 , in combination with tislelizumab , BeiGene Ltd.'s anti - PD - 1 antibody , and chemotherapy , in patients with gastric or gastroesophageal junction cancer ( G / GEJ ) , at the European Society for Medical Oncology ( ESMO ) Congress . The Company will host a conference call on Friday , September 17 , 2021 to discuss preliminary results from the study . The Company announced positive initial data from the DisTinGuish study on Monday , September 13 , 2021 based on 25 G / GEJ patients enrolled in the trial that showed DKN - 01 in combination with tislelizumab and chemotherapy as first - line therapy was well tolerated with compelling activity . The results presented at the ESMO Congress today included additional patient data stratified by tumoral PD - L1 expression levels based on visually- estimated combined positive score ( vCPS ) , showing that robust objective clinical responses can be achieved from this combination regimen independently of PD - L1 expression . " Initial data from this trial have shown that patients with high levels of DKK1 expression , a group with a poor prognosis , had encouraging responses to treatment . The additional data presented today show evidence that not only is DKK1 a critical biomarker in predicting response to DKN - 01 and tislelizumab therapy , but also that the combination can induce deep responses regardless of the patient's PD - L1 status , including particularly poor prognosis patients with both low PD - L1 and high DKK1 , " said Samuel Klempner , MD , Member of the Faculty at Massachusetts General Hospital Cancer Center and Harvard Medical School . " Taken together , these are promising results for the combination therapy of DKN - 01 with tislelizumab and chemotherapy in first line patients with gastric or gastroesophageal junction cancers . " About the DisTinGuish Study The Distinguish study ( NCT04363801 ) is a Phase 2a study of DKN - 01 in combination with tislelizumab , an anti - PD - 1 antibody , with or without chemotherapy as first - line or second - line therapy in patients with inoperable , locally advanced , G / GEJ adenocarcinoma . The study is being conducted in two parts in the United States and the Republic of Korea . Enrollment of Part A has been completed with 25 first - line HER2- G / GEJ cancer patients whose tumors express either high levels of DKK1 ( DKK1 - high ) or low levels of DKK1 ( DKK1 - low ) . Part B of the study will enroll up to 48 patients with second - line , DKK1 - high G / GEJ cancer . Leap is conducting this combination study as part of an exclusive option and license agreement with BeiGene for the development of DKN - 01 in Asia ( excluding Japan ) , Australia , and New Zealand . Key Findings • Among patients who received a full cycle of DKN - 01 therapy , the ORR was 68.2 % , with 90 % ORR in DKK1 - high patients and 56 % in DKK1 - low patients • Response was independent of PD - L1 expression , and particularly strong in the less favorable to checkpoint inhibitor therapy , PD - L1 low ( vCPS < 5 ) , population o Among those patients with PD - L1 - low expression ( vCPS < 5 ) , the ORR was 79 % , with 100 % in DKK1 - high patients and 57 % in DKK1 - low patients o Among those patients with PD - L1 - high expression ( VCPS ≥ 5 ) , the ORR was 67 % , with 75 % ORR in DKK1 - high patients and 50 % in DKK1 - low patients • DKK1 levels could not be determined in one patient who had PD - L1 expression data ; however , the patient's PD - L1 expression level was determined to be low ( vCPS score 0 ) and the patient achieved a partial response • DKK1 expression and PD - L1 expression are not correlated • Median duration of response and progression - free survival data are not yet mature , and patient follow - up continues Twenty - five first - line patients were enrolled , and as of the cut - off date of the presentation , 15 patients had experienced a partial response ( PR ) , six patients had a best response of stable disease ( SD ) , one patient was non - evaluable for response ( NE ) , and three patients were unable to complete a full cycle of DKN - 01 therapy ( non - modified ITT ( MITT ) ) . Among the 21 patients that had RNAscope® DKK1 expression available , 12 were DKK1 - high [ 9 PR , 1 NE , 2 non - mITT ] and 9 were DKK1 - low [ 5 PR , 4 SD ] . Among the 20 patients that had PD - L1 expression available , 14 were PD - L1 low vCPS < 5 [ 11 PR , 3 SD ] and 6 were PD - L1 high vCPS ≥ 5 [ 4 PR , 1 SD , 1 NE ] .