Bleeding events in the fitusiran efficacy and BPA/CFC prophylaxis period (EAS 1). (A) ABRs for treated bleeds (estimated by negative binomial model). (B) ABRs for treated bleeds by inhibitor status (estimated by negative binomial model). (C) Number of treated bleeds. ∗Includes all participants who received BPA/CFC prophylaxis and at least 1 dose of 80 mg fitusiran before dose resumption (after the sponsor initiated pause in dosing). ^†P value from a negative binomial regression model with study period (fitusiran efficacy period or BPA/CFC prophylaxis period) as a fixed effect and a robust sandwich covariance matrix constructed to account for the within subject dependence, the logarithm of the duration (in years) that each participant spends in each study period matching the bleeding episode data being analyzed as an offset variable (P value vs null hypothesis of ratio = 1). ^‡The BPA/CFC prophylaxis period was defined as starting on day –168 to day –1 or the last day of bleeding follow-up, whichever was the earliest. ^§Fitusiran efficacy period was defined as starting on day 29 after the first dose of fitusiran up to day 197 or the last day of bleeding follow-up, whichever was the earliest.