Investigators sought information on adverse events (AEs) at each contact with participants. The WHO toxicity grading scale was used for assessing AE severity (i.e., intensity of an AE); any AEs not specifically listed in the WHO toxicity grading scale were assessed for severity according to the following grades: Grade 1 is mild; Grade 2 is moderate, Grade 3 is severe; Grade 4 is life-threatening; and Grade 5 is death. Regardless of severity, some AEs may have also met seriousness criteria. The terms "severe" and "serious" are not synonymous; severity and seriousness were independently assessed for each AE. aPCC = activated prothrombin complex concentrate

Safety Population: all participants who received at least one dose of emicizumab

Investigators sought information on adverse events (AEs) at each contact with participants. The WHO toxicity grading scale was used for assessing AE severity (i.e., intensity of an AE); any AEs not specifically listed in the WHO toxicity grading scale were assessed for severity according to the following grades: Grade 1 is mild; Grade 2 is moderate, Grade 3 is severe; Grade 4 is life-threatening; and Grade 5 is death. Regardless of severity, some AEs may have also met seriousness criteria. The terms "severe" and "serious" are not synonymous; severity and seriousness were independently assessed for each AE. The AE rate per 100 patient-years was computed as follows: AE Rate = (Number of AEs observed/ Total patient-years at risk)*100. Total patient-years at risk is the sum over all patients of the time intervals (in years) between start of study therapy (study day 1) and the end of follow up.

Safety Population: all participants who received at least one dose of emicizumab

The World Health Organization (WHO) toxicity grading scale was used for determining the severity of laboratory abnormalities (i.e., test results outside of the reference range) for hematology and biochemistry parameters; Grade 0 is normal and Grades 1 to 4 represent worsening levels of the parameter outside of the normal range in the specified direction of the abnormality (high and low are above and below the range, respectively). Not every laboratory abnormality qualified as an adverse event (AE). A laboratory test result was reported as an AE if it met any of the following criteria: was accompanied by clinical symptoms; resulted in a change in study treatment; resulted in a medical intervention or a change in concomitant therapy; or was clinically significant in the investigator's judgment. Baseline was defined as the last available assessment prior to first receipt of study drug. Abs = absolute count; SGOT/AST = aspartate aminotransferase; SGPT/ALT = alanine aminotransferase

Safety Population: all participants who received at least one dose of emicizumab

Vital signs that were measured included body temperature, pulse and respiratory rates, systolic and diastolic blood pressure, and weight. On treatment days, measurement occurred prior to emicizumab administration.

Safety Population: all participants who received at least one dose of emicizumab. The number analyzed included participants with a baseline value and a post-baseline value at a given timepoint.

Vital signs that were measured included body temperature, pulse and respiratory rates, systolic and diastolic blood pressure, and weight. On treatment days, measurement occurred prior to emicizumab administration.

Safety Population: all participants who received at least one dose of emicizumab. The number analyzed included participants with a baseline value and a post-baseline value at a given timepoint.

Vital signs that were measured included body temperature, pulse and respiratory rates, systolic and diastolic blood pressure, and weight. On treatment days, measurement occurred prior to emicizumab administration.

Safety Population: all participants who received at least one dose of emicizumab. The number analyzed included participants with a baseline value and a post-baseline value at a given timepoint.

Vital signs that were measured included body temperature, pulse and respiratory rates, systolic and diastolic blood pressure, and weight. On treatment days, measurement occurred prior to emicizumab administration.

Safety Population: all participants who received at least one dose of emicizumab. The number analyzed included participants with a baseline value and a post-baseline value at a given timepoint.

Vital signs that were measured included body temperature, pulse and respiratory rates, systolic and diastolic blood pressure, and weight. On treatment days, measurement occurred prior to emicizumab administration.

Safety Population: all participants who received at least one dose of emicizumab. The number analyzed included participants with a baseline value and a post-baseline value at a given timepoint.

Vital signs that were measured included body temperature, pulse and respiratory rates, systolic and diastolic blood pressure, and weight. On treatment days, measurement occurred prior to emicizumab administration.

Safety Population: all participants who received at least one dose of emicizumab. The number analyzed included participants with a baseline value and a post-baseline value at a given timepoint.

The number of bleeds over the efficacy period was analyzed as an ABR using a negative binomial regression model. Treated bleeds: bleeds followed by a hemophilia medication reported to be a "Treatment for bleed". All bleeds: included both treated and non-treated bleeds. Treated joint bleeds: treated bleeds where bleed type was "joint bleed" accompanied by at least one of following symptoms: "increased swelling or warmth of the skin over the joint", "increasing pain" or "decreased range of motion or difficulty using the joint compared with baseline". Treated target joint bleeds: treated joint bleeds that occurred in a target joint, defined as a joint in which ≥3 treated joint bleeds occurred during the 24 weeks prior to study entry. Treated spontaneous bleeds: treated bleeds with no other known contributing factor such as trauma or procedure/surgery. For all bleed types, bleeds due to surgery/procedure were excluded. Bleeds occurring after dose up-titration have been excluded.

Intent-to-Treat (ITT) Population: all enrolled participants

The number of bleeds over the efficacy period was calculated as: ABR = (number of bleeds/number of days during the efficacy period) x 365.25. Treated bleeds: bleeds followed by a hemophilia medication reported to be a "Treatment for bleed". All bleeds: included both treated and non-treated bleeds. Treated joint bleeds: treated bleeds where bleed type was "joint bleed" accompanied by at least one of following symptoms: "increased swelling or warmth of the skin over the joint", "increasing pain" or "decreased range of motion or difficulty using the joint compared with baseline". Treated target joint bleeds: treated joint bleeds that occurred in a target joint, defined as a joint in which ≥3 treated joint bleeds occurred during the 24 weeks prior to study entry. Treated spontaneous bleeds: treated bleeds with no other known contributing factor such as trauma or procedure/surgery. For all types, bleeds due to surgery/procedure and bleeds occurring after dose up-titration were excluded.

Intent-to-Treat (ITT) Population: all enrolled participants

The number of bleeds over the efficacy period was calculated as: ABR = (number of bleeds/number of days during the efficacy period) x 365.25. Treated bleeds: bleeds followed by a hemophilia medication reported to be a "Treatment for bleed". All bleeds: included both treated and non-treated bleeds. Treated joint bleeds: treated bleeds where bleed type was "joint bleed" accompanied by at least one of following symptoms: "increased swelling or warmth of the skin over the joint", "increasing pain" or "decreased range of motion or difficulty using the joint compared with baseline". Treated target joint bleeds: treated joint bleeds that occurred in a target joint, defined as a joint in which ≥3 treated joint bleeds occurred during the 24 weeks prior to study entry. Treated spontaneous bleeds: treated bleeds with no other known contributing factor such as trauma or procedure/surgery. For all types, bleeds due to surgery/procedure and bleeds occurring after dose up-titration were excluded.

Intent-to-Treat (ITT) Population: all enrolled participants

Treated bleeds: bleeds followed by a hemophilia medication reported to be a "Treatment for bleed". Bleeds due to surgery/procedure were excluded. The 72-hour rule was implemented: two bleeds of the same type and at the same anatomical location are counted as one bleed if the second bleed occurs within 72 hours from the last treatment for the first bleed. Included data before up-titration only, for participants whose dose was up-titrated.

Intent-to-Treat (ITT) Population: all enrolled participants

All bleeds: included both treated and non-treated bleeds. Bleeds due to surgery/procedure were excluded. The 72-hour rule was implemented: two bleeds of the same type and at the same anatomical location are counted as one bleed if the second bleed occurs within 72 hours from the last treatment for the first bleed. Included data before up-titration only, for participants whose dose was up-titrated.

Intent-to-Treat (ITT) Population: all enrolled participants

Treated spontaneous bleeds: treated bleeds with no other known contributing factor such as trauma or procedure/surgery. Bleeds due to surgery/procedure were excluded. The 72-hour rule was implemented: two bleeds of the same type and at the same anatomical location are counted as one bleed if the second bleed occurs within 72 hours from the last treatment for the first bleed. Included data before up-titration only, for participants whose dose was up-titrated.

Intent-to-Treat (ITT) Population: all enrolled participants

The number of bleeds over the efficacy period was calculated as an ABR for each participant using the following formula: ABR = (number of bleeds/number of days during the efficacy period) x 365.25. Treated bleeds: bleeds followed by a hemophilia medication reported to be a "Treatment for bleed". Bleeds due to surgery/procedure were excluded. The 72-hour rule was implemented: two bleeds of the same type and at the same anatomical location are counted as one bleed if the second bleed occurs within 72 hours from the last treatment for the first bleed. Included data before up-titration only, for participants whose dose was up-titrated.

Intent-to-Treat (ITT) Population: all enrolled participants

The number of bleeds over the efficacy period was calculated as an ABR for each participant using the following formula: ABR = (number of bleeds/number of days during the efficacy period) x 365.25. All bleeds: included both treated and non-treated bleeds. Bleeds due to surgery/procedure were excluded. The 72-hour rule was implemented: two bleeds of the same type and at the same anatomical location are counted as one bleed if the second bleed occurs within 72 hours from the last treatment for the first bleed. Included data before up-titration only, for participants whose dose was up-titrated.

Intent-to-Treat (ITT) Population: all enrolled participants

The number of bleeds over the efficacy period was calculated as an ABR for each participant using the following formula: ABR = (number of bleeds/number of days during the efficacy period) x 365.25. Treated spontaneous bleeds: treated bleeds with no other known contributing factor such as trauma or procedure/surgery. Bleeds due to surgery/procedure were excluded. The 72-hour rule was implemented: two bleeds of the same type and at the same anatomical location are counted as one bleed if the second bleed occurs within 72 hours from the last treatment for the first bleed. Included data before up-titration only, for participants whose dose was up-titrated.

Intent-to-Treat (ITT) Population: all enrolled participants

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. The Total Score is based on the scores for each domain and ranges from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. The Total Score is based on the scores for each domain and ranges from 0 to 100, with lower scores reflective of better quality of life. An improvement larger than the responder threshold was defined as a decrease from baseline of at least 7 points in the Haem-A-QoL Total score.

The number analyzed represents the number of adult participants responding to the questionnaire who had a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life. An improvement larger than the responder threshold was defined as a decrease from baseline of at least 10 points in the Haem-A-QoL Physical Health domain score.

The number analyzed represents the number of adult participants responding to the questionnaire who had a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haem-A-QoL questionnaire was designed for adult participants (greater than or equal to 18 years old) with hemophilia. It consists of 46 items comprising 10 domains: physical health, treatment, work and school, dealing with hemophilia, feelings, familly planning, future, partnerships and sexuality, sports and leisure, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always; although, for some items there is also a 'not applicable' option. Scale scores for each domain range from 0 to 100, with lower scores reflective of better quality of life.

The number analyzed represents the number of adult participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. The Total Score is derived from the scores for all domains and scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. The Total Score is derived from the scores for all domains and scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life. An improvement larger than the responder threshold was defined as a decrease of at least 5 points in the Haemo-QoL-SF Total score.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life. An improvement larger than the responder threshold was defined as a decrease of at least 10 points in the Haemo-QoL-SF Physical Health domain score.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The Haemo-QoL-SF was designed as a series of age-related questionnaires to measure health-related quality of life in children and adolescents (12-17 year olds) with hemophilia. This version contains 35 items and covers nine domains considered relevant for children's health-related quality of life: physical health, treatment, sports and school, dealing with hemophilia, feelings, family, friends, other people, and view of yourself. Items are rated by participants with one of five response options: never, seldom, sometimes, often, and always. Scale scores range from 0 to 100, with a lower score reflective of better health-related quality of life.

The number analyzed represents the number of adolescent participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The EQ-5D-5L is a generic, self-reported, preference-based health utility measure that consists of six questions and is used to assess health status and inform pharmacoeconomic evaluations. The index utility score is based on the participant's assessment of their health on five scales: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. It ranges from -0.224 to 1, with 0 corresponding to death and 1 corresponding to full health; negative values correspond to health states worse than death. Higher scores indicate better quality of life.

The number analyzed represents the number of participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The EQ-5D-5L is a generic, self-reported, preference-based health utility measure that consists of six questions and is used to assess health status and inform pharmacoeconomic evaluations. The visual analogue scale (VAS) ranges from 0 to 100 points, on which the participant self-assesses their current health status; 0 being the worst health you can imagine and 100 being the best health you can imagine. Higher scores are reflective of better health.

The number analyzed represents the number of participants responding to the questionnaire who had a baseline value and a post-baseline value at a given timepoint.

The EmiPref questionnaire asked participants to specify the treatment they would prefer to continue to receive after receiving treatment with their previous episodic or prophylactic regimen and subcutaneous (SC) emicizumab, or if they had no preference. The 95% confidence intervals were calculated for one sample binomial using the Pearson-Clopper method.

The number of participants analyzed represents the total number who responded to this questionnaire.

'Total ADA Negative' is the sum of all subjects who tested negative for ADA in the 2 following categories: 'ADA Negative', those who are pre-dose ADA negative or are missing pre-dose ADA data and who have all negative post-dose ADA results; and 'ADA Negative (Treatment Unaffected)', a subset who are pre-dose ADA positive but do not have a ≥4-fold increase in post-dose ADA levels compared to baseline measurement. 'Total ADA Positive' is the sum of all subjects who tested positive for ADA in the 2 following categories: 'ADA Positive (Treatment Boosted)', those who are pre-dose ADA positive and have a ≥4-fold increase in post-dose ADA levels compared to baseline measurement; and 'ADA Positive (Treatment Induced)', those who are pre-dose ADA negative or missing data and who have at least one post-dose ADA positive sample.

Safety Population: all participants who received at least one dose of emicizumab. The number analyzed included participants with at least one baseline and one post-baseline assessments.

The trough concentration is a measure of the plasma concentration of a study drug at the end of of the dosage interval.

Pharmacokinetic-Evaluable Population: all participants who received at least one dose of emicizumab and had at least one post-baseline emicizumab concentration result.