About “The Day One Talk”

“This was their first child.

And now we're going to have to explain that she had this tumor behind her eye and that we're going to have to treat her with chemotherapy and it was going to be complicated and we had these unknowns and was just hoping that we got through this and that they didn't walk away worried.

We wanted them to walk away feeling like they had confidence in us that we knew what we were doing. And you could tell, because they were really looking. You could tell when families that you're sitting with are looking to you for answers and looking to you for hope.”

—Dr Sam Blackman, on meeting the Glennon Family for the first time


One Family’s Perspective

The Physician’s Perspective

About Drs. Sam and Mark

Samuel Blackman, M.D., Ph.D. is Day One’s co-founder and has served as Chief Medical Officer since November 2018. Prior to co-founding Day One, Dr. Blackman was Head of Clinical Development at Mavupharma, a drug discovery company focused on leveraging the immune system to treat cancer and infectious diseases, from September 2018 to July 2019. Prior to Mavupharma, he was Head of Clinical Development at Silverback Therapeutics, a biotechnology company developing tissue-targeted therapeutics, from August 2016 to September 2018. Prior to Silverback, Dr. Blackman was a senior medical director at Juno Therapeutics, a biotechnology company focused on cancer treatments from June 2014 to August 2016, and before that he held roles of increasing responsibility at Seattle Genetics, Merck, and GlaxoSmithKline. He is a graduate of the pediatric hematology/oncology fellowship program at the Dana Farber Cancer Institute and Children’s Hospital Boston, and the pediatric residency program at Cincinnati Children’s Hospital Medical Center. Dr. Blackman received his B.A. in Philosophy, his M.D. and Ph.D. in Pharmacology from the University of Illinois at Chicago.

Mark Kieran, MD is the VP of Clinical Development at Day One. He received a PhD in Immunology from the University of Alberta, Canada in 1983 and his MD in 1986 from the University of Calgary. After a post-doctoral fellowship in the Department of Molecular Biology at the Pasteur Institute in Paris, France where he cloned the regulatory molecule NFkB, he completed a pediatric residency at McGill University in Montreal and a pediatric oncology fellowship at Boston Children’s Hospital. Dr. Kieran became Director of Pediatric Neuro-Oncology at the Dana-Farber Cancer Institute in 1998 focused on targeted, gene, immune modulatory and antiangiogenic therapies for pediatric brain tumor patients and other rare cardiac and premature aging diseases. Dr Kieran moved to Bristol-Myers Squibb in 2018 where he was the Senior Director of Pediatric Oncology until July 2021.


The Together from Day One video series was created by a partnership between Day One Biopharmaceuticals and Entertainment 2 Affect Change.

Inspired by the urgent needs of children with cancer, Day One creatively and intentionally develops new medicines for people of all ages with life-threatening diseases.

Our name was inspired by “The Day One Talk,” a life-altering moment for both children and their families. We exist to dramatically change the outlook for families who receive the devastating news of a cancer diagnosis or other life-threatening disease.

Entertainment 2 Affect Change (E2AC) is a 501(c)(3) that connects award-winning content creators, mission-based organizations, and passionate funders who want to share their impact through the power of story.

We tell stories that entertain, engage, educate, and inspire.

Learn more at E2AC.org.