Dr. Sassine pursued a fellowship in Infectious Diseases, Immunocompromised Track, at the University of Texas Health Science Center and MD Anderson Cancer Center in Houston, TX, where he also served as a Chief Fellow. He is currently an Assistant Professor of Medicine at the Infectious Diseases Section in the University of Oklahoma Health Sciences Center.

He specializes in diagnosing and treating infections in immunocompromised hosts, including transplant recipients and patients with cancer. His research interests include infections in patients with hematological malignancies, including hematopoietic cell transplantation and CAR T cell recipients.