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Day One BIOPHARMACEUTICALS Day One Reports Second Quarter 2021 Financial Results and Corporate Progress August 10 , 2021 DAY101 Granted Rare Pediatric Disease Designation from FDA DAY101 Granted Orphan Designation from European Commission Dosed the First Patients in Pivotal FIREFLY - 1 Clinical Trial of DAY101 in Patients with pLGG Successfully Completed $ 184 Million Upsized Initial Public Offering Providing Funding into the Second Half of 2023 SOUTH SAN FRANCISCO , Calif . , Aug. 10 , 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 second quarter of 2021 and highlighted recent corporate achievements . " Day One made significant progress across multiple clinical and corporate initiatives during the second quarter of 2021 , including dosing the first patients in our ongoing FIREFLY - 1 pivotal study of DAY101 in pediatric low - grade glioma , " said Jeremy Bender , Ph.D. , chief executive officer of Day One . " The success of our recent IPO reflects a strong commitment from our investors who , like all of us at Day One , recognize the therapeutic potential of DAY101 . Entering the second half of 2021 , we remain well positioned to advance our pipeline through key data readouts with the goal of fulfilling our mission of developing novel medicines to improve the lives of patients of all ages living with cancer . " Program Highlights • The Company announced first patients dosed in the FIREFLY - 1 pivotal clinical trial of DAY101 in pediatric low - grade glioma ( PLGG ) . FIREFLY - 1 is being conducted in collaboration with the Pacific Pediatric Neuro - Oncology Consortium ( PNOC ) and is designed to support the regulatory approval of DAY101 . Initial data from FIREFLY - 1 is expected in the first half of 2022 . • Day One has initiated a Phase 2 monotherapy trial of DAY101 in adult patients with recurrent , progressive , or refractory solid tumors harboring MAPK pathway aberrations . • The U.S. Food and Drug Administration ( FDA ) has granted Rare Pediatric Disease Designation to DAY101 for the treatment of low - grade gliomas harboring an activating RAF alteration that disproportionately affects children . If a New Drug Application in the United States for DAY 101 is approved , Day One may be eligible to receive a Priority Review Voucher ( PRV ) from the FDA , which can be redeemed to obtain priority review for any subsequent marketing application or may be sold or transferred . • The European Commission granted DAY101 Orphan Designation for the treatment of glioma based upon a positive opinion from the European Medicines Agency Committee for Orphan Medicinal Products . Corporate Highlights • The Company announced the successful closing of its upsized initial public offering , raising gross proceeds of $ 184.0 million , bringing total cash , cash equivalents and marketable securities to $ 310.0 million at the end of June 30 , 2021. The company expects its current cash position to fund operations into the second half of 2023 and through key clinical milestones . • Day One appointed Saira Ramasastry to its Board of Directors . Ms. Ramasastry currently serves as the Managing Partner of Life Sciences Advisory , LLC , and brings more than 20 years of experience to the Board as a life sciences - focused strategic consultant and investment banker . Second Quarter 2021 Financial Highlights • Cash Position : Cash and cash equivalents and short - term investments totaled $ 310.0 million at June 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 $ 9.9 million for the second quarter 2021 and $ 1.4 million for the second quarter 2020. The increase was primarily due to additional employee compensation costs , clinical trial