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Day One BIOPHARMACEUTICALS Day One Reports Third Quarter 2021 Financial Results and Corporate Progress November 8 , 2021 Enrollment Progresses in the Pivotal Phase 2 FIREFLY - 1 Clinical Trial of DAY101 in Patients with pLGG ; Initial Data Expected in 1H 2022 Upcoming CTOS Meeting to Highlight Single Agent Activity of Lead Drug Candidate , DAY101 , in Spindle Cell Carcinoma Compassionate Use Case SOUTH SAN FRANCISCO , Calif . , Nov. 08 , 2021 ( GLOBE NEWSWIRE ) -- Day One Biopharmaceuticals ( Nasdaq : DAWN ) , a clinical - stage biopharmaceutical company dedicated to developing and commercializing targeted therapies for patients of all ages with genomically defined cancers , today announced financial results for the third quarter of 2021 and highlighted recent corporate achievements . " We continue to build momentum in our lead program with the granting of Rare Pediatric Disease Designation for DAY101 for the treatment of pediatric low - grade glioma during the third quarter , " said Jeremy Bender , Ph.D. , chief executive officer of Day One . " Additionally , with the further strengthening of our leadership team and continued progress with enrollment in our pivotal Phase 2 study , FIREFLY - 1 , we remain on track to present initial clinical data from this trial in the first half of 2022. We continue to grow our company , advance our development programs , and work to achieve our mission of impacting the lives of all people with cancer , whatever their age , starting from Day One . " Program Highlights • FIREFLY - 1 , a pivotal Phase 2 clinical trial of DAY101 in pediatric low - grade glioma ( pLGG ) , continues active enrollment ; initial data are expected in the first half of 2022. The single arm , open - label , global registrational Phase 2 study is anticipated to enroll 60 patients and has activated approximately 25 sites globally . • Day One will present a poster at the 2021 Connective Tissue Oncology Society ( CTOS ) Virtual Annual Meeting on November 12 , 2021. The poster reviews a compassionate use case of a child with recurrent spindle cell sarcoma harboring a novel SNX8 - BRAF gene fusion who had exhausted all treatment options , including a MEK inhibitor , and was treated with DAY101 monotherapy . Following treatment , the patient's symptoms resolved and there was no evidence of measurable disease at the site of previously visualized tumor , indicating a complete response to treatment with DAY101 . • Day One is also conducting a Phase 2 monotherapy trial of DAY101 in adult patients with recurrent , progressive , or refractory solid tumors harboring MAPK pathway aberrations . Corporate Highlights • Day One strengthened its leadership team with appointment of Jaa Roberson as chief people officer . Ms. Roberson will oversee all aspects of Day One's human resources and talent acquisition efforts as the Company continues to grow . • The Company recently expanded its board of directors with the appointment of Scott Garland . Mr. Garland is a 30 - year veteran of the biopharmaceutical industry with deep commercial and executive leadership experience . Third Quarter 2021 Financial Highlights • Cash Position : Cash and cash equivalents and short - term investments totaled $ 297.2 million at September 30 , 2021 . Based on Day One's current operating plan , management believes it has sufficient capital resources to fund anticipated operations into the second half of 2023 . • R & D Expenses : Research and development expenses were $ 9.8 million for the third quarter 2021 compared to $ 2.5 million for the third quarter 2020. The increase was primarily due to additional employee compensation costs , clinical trial expenses , and CMC activity . • G & A Expenses : General and administrative expenses were $ 9.4 million for the third quarter 2021 compared to $ 1.0 million for the third quarter 2020. The increase was primarily due to additional employee compensation costs , legal , and professional expenses associated with operating as a public company . • Net Loss : Net loss totaled $ 19.2 million and $ 3.8 million for the third quarters of 2021 and 2020 , respectively , with non - cash stock compensation expense of $ 5.1 million and $ 0.1 million for the third quarters of 2021 and 2020 ,