In this week's episode, Blood editor Dr. James Griffin interviews Drs. Johnny Mahlangu and Joseph Rocco on their articles published in volume 147 issue 9 of Blood.  Dr. Mahlangu discusses study details and next steps from "Efficacy and safety of marstacimab prophylaxis in hemophilia A/B with inhibitors: results from the phase 3 BASIS trial" which shows that bleeding was reduced by 93% with subcutaneous marstacimab. Dr. Rocco shares the development behind "CXCL9 as a novel prognostic marker to identify high-risk adults with hemophagocytic lymphohistiocytosis", and the insights gained from measuring a new surrogate marker of IFN-γ activity predicting severity and mortality.