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cullinan ONCOLOGY Cullinan Oncology Announces Phase 1 / 2a Interim Data For Cullinan Pearl's CLN - 081 in NSCLC EGFR Exon 20 Patients June 4 , 2021 • CLN - 081 Continues to Demonstrate Acceptable Overall Safety and Tolerability , With Encouraging GI Toxicity Profile • As of the Data Cutoff , No Grade 3 TRAE Diarrhea at Doses Below 150mg BID ; No Grade 3 Rash TRAES • Objective Responses Were Observed Across the Dose Range , with a Confirmed Objective Response Rate of 46 % in Patients Treated at 100 mg BID • ⚫ Phase 2a Expansion Initiated at 100 mg BID CAMBRIDGE , Mass . , June 04 , 2021 ( GLOBE NEWSWIRE ) -- Cullinan Oncology , Inc. ( Nasdaq : CGEM ) ( " Cullinan ” ) , an oncology company seeking to drive shareholder returns by focusing on the patient , today announced additional details pertaining to Cullinan Pearl's ongoing Phase 1 / 2a trial of CLN - 081 in Non - Small Cell Lung Cancer ( NSCLC ) patients whose tumors harbor epidermal growth factor receptor ( EGFR ) exon 20 insertion mutations . CLN - 081 is an orally available , irreversible EGFR inhibitor , utilizing a unique pyrrolopyrimidine scaffold that was designed to selectively target cells expressing mutant EGFR variants , including exon 20 , while sparing cells expressing wild type ( WT ) EGFR . These data will be featured in an on - demand poster presentation available this morning at 9:00 am EDT at the 2021 American Society of Clinical Oncology ( ASCO ) Annual Meeting and during a company sponsored webinar at 10:30 am EDT today , which can be accessed here or in the ' Events ' section on Cullinan's investor website . " We remain encouraged with CLN - 081's emerging profile , " stated Owen Hughes , Cullinan's Chief Executive Officer . “ In heavily pretreated patients , CLN - 081 continues to show antitumor activity across the dose range , with a safety profile that appears to be differentiated , most specifically with respect to Gl adverse events . " The current analysis of the ongoing trial evaluated a total of 45 NSCLC patients with EGFR exon 20 insertion mutations who received at least one dose of CLN - 081 as of the April 1 , 2021 , data cutoff , and were evaluable for safety . CLN - 081 was dosed orally , at dose levels including 30 , 45 , 65 , 100 and 150 mg twice daily ( BID ) . As of the data cutoff , 42 of 45 patients were response evaluable across all dose cohorts tested . Overall Safety : Regarding treatment related adverse events ( TRAEs ) associated with WT EGFR inhibition : • Rash has been limited to Grade 1 and 2 events ( 76 % of patients experienced an event across all doses as of the data cutoff ) ; events were manageable with conventional supportive care ; no patients have experienced Grade ≥3 TRAE rash . • Similarly , diarrhea has been mostly limited to Grade 1 and 2 events ( 22 % across the dose range ) as of the data cutoff , with a single Grade ≥3 TRAE at the highest dose tested to date , 150 mg BID , which resolved with supportive care . No prophylactic regimen has been required to ameliorate the incidence or severity of diarrhea to date . Overall Efficacy : Objective partial responses ( PR ) were observed in 21 of 42 ( 50 % ) response evaluable patients treated across all dose levels . • Of the 21 PRS as of the data cutoff , 13 were confirmed ( 31 % confirmed objective response rate ) , 5 were pending confirmation ( i.e. , patient had not reached their second post - baseline disease assessment as of the data cutoff ) , and 3 will remain unconfirmed . o 41 of 42 ( 98 % ) response evaluable patients have achieved a best response of stable disease ( SD ) or PR , with 76 % of all patients showing some degree of tumor regression at the initial scan post baseline ( week 6 ) . 100 mg BID Expansion Cohort : In February 2021 , Cullinan announced a Phase 2a expansion at the 100mg BID cohort , allowing enrollment of up to 36 patients . 。 Safety : Treatment - related rash has been limited to Grade 1 and 2 events ( 66 % ) , manageable with conventional supportive care ; no patients have experienced Grade ≥3 TRAE rash . In addition , the overall incidence of treatment - related diarrhea