Arnon Nagler, MD, Chaim Sheba Medical Center, Tel-Aviv, Israel, shares his views on whether post-transplant cyclophosphamide (PTCy) is superior to anti-thymocyte globulin (ATG) as prophylaxis in haploidentical transplant. Prof. Nagler outlines the mechanism of action of PTCy, reporting that it reduces transplanted-related mortality, but comments that further studies are needed to compare it’s efficacy to that of ATG. This interview took place at the 6th Congress on Controversies in Stem Cell Transplantation and Cellular Therapies (COSTEM), which took place virtually.