A Pharmacokinetic, Tolerability and Safety Study of Icatibant in Children and Adolescents With Hereditary Angioedema

A Pharmacokinetic, Tolerability and Safety Study of Icatibant in Children and Adolescents With Hereditary Angioedema

A Multicenter, Open-Label, Non-Randomized Study to Assess the Pharmacokinetics, Tolerability, and Safety of a Single Subcutaneous Administration of Icatibant in Children and Adolescents With Hereditary Angioedema

HGT-FIR-086 is a multicenter, open-label, non-randomized, single-arm study to evaluate the Pharmacokinetics, tolerability,safety, and efficacy on reproductive hormones, of a single subcutaneous (SC) administration of icatibant in approximately 30 pediatric subjects with Hereditary Angioedema (HAE) during an initial acute attack.

Study HGT-FIR-086 will enroll 30 subjects from 2 to less than 18 years of age, divided into 2 groups: prepubertal and pubertal/postpubertal. At least 10 prepubertal children and at least 20 adolescents (including 10 treated during a HAE attack) must be enrolled in the study. After a qualifying screening period, the PK, safety/tolerability, and efficacy of treatment with SC icatibant will be evaluated in at least 20 subjects (10 prepubertal and 10 pubertal/postpubertal subjects) who present with cutaneous, abdominal, or laryngeal symptoms of an acute attack of HAE. The PK and safety/tolerability of SC icatibant will be evaluated in at least 10 additional pubertal/postpubertal subjects who meet screening criteria and receive treatment with SC icatibant in the absence of a current acute HAE attack. The planned duration of active participation for subjects who present with an initial attack of acute HAE will consist of treatment with a single subcutaneous injection of icatibant on Day 1 through follow up at day 90. After having received initial treatment with icatibant, either during or in the absence of an attack, at least 10 pubertal/postpubertal subjects who subsequently experience an acute HAE attack may continue to receive treatment with icatibant as a single SC administration per attack for a total of 3 eligible icatibant-treated attacks. The period of active participation in the study for prepubertal subjects will be approximately 90 days, while that for pubertal/postpubertal subjects could be a maximum of approximately 270 or 360 days (3 separate active periods of approximately 90 days for those treated with icatibant during an attack; 4 separate active periods for those treated without an attack), with each active period separated by periods of inactive participation of variable duration.

Efficacy, Hereditary angioedema, HAE, Pediatric, Children, Pharmacokinetics, Safety, Firazyr, icatibant

Area Under the Plasma Concentration-time Curve From Time Zero to 4 Hours Post-dose (AUC0-4) of a Single Subcutaneous (SC) Dose of Icatibant

Area under the plasma concentration-time curve from time zero to 4 hours post-dose (AUC0-4) of a single SC dose of icatibant was reported.

Area Under the Plasma Concentration-time Curve From Time Zero to 6 Hours Post-dose (AUC0-t) of a Single Subcutaneous (SC) Dose of Icatibant

Area under the plasma concentration-time curve from time zero to 6 hours post-dose (AUC0-t) of a single SC dose of icatibant was reported.

Area Under the Plasma Concentration-time Curve From Time Zero to Infinity (AUC0-inf) of a Single Subcutaneous (SC) Dose of Icatibant

Area under the plasma concentration-time curve from time zero to infinity (AUC0-inf) of a single SC dose of icatibant was reported.

Vital signs included pulse rate, blood pressure, respiration rate, and temperature. The number of participants who reported clinically significant changes in vital signs were reported.

A standard 12-lead ECG was performed after 10 minutes at rest when the participant was seated or supine following treatment. The number of participants who reported clinically significant changes in ECGs were reported.

Clinical laboratory evaluations included clinical chemistry (including liver function tests), hematology, urinalysis. The number of participants who reported clinically significant changes in clinical laboratory evaluations were reported.

An AE was any noxious, pathologic, or unintended change in anatomical, physiologic, or metabolic function as indicated by physical signs, symptoms, or laboratory changes occurring in a clinical study, whether or not considered investigational product related.

The number of participants with injection site reactions (erythema, swelling, burning sensation, itching/pruritus, warm sensation, cutaneous pain, or other) that occured after initial icatibant administration was reported.

Number of Participants Who Reported Injection Site Reactions (ISR) for Icatibant Exposure Number 2 and 3

The number of participants with injection site reactions (erythema, swelling, burning sensation, itching/pruritus, warm sensation, cutaneous pain, or other) that occurred after subsequent icatibant administration by study-site personnel (health care practitioner [HCP] administration) or by caregiver/self (caregiver administration) was reported. In the below table, E-2 refers to icatibant exposure 2 and E-3 refers to icatibant exposure 3.

Reproductive hormone levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, and progesterone in females, and FSH, LH, and testosterone in males were measured. The number of participants with clinically significant changes in reproductive hormones was reported.

Time to Onset of Symptom Relief (TOSR) for Composite Investigator-Assessed Symptom Scores for Icatibant Exposure Number 1

The TOSR was defined as the duration of time in hours from study drug administration to the earliest time post-treatment at which there was at least a 20 percent (%) improvement in the average post-treatment symptom score with no worsening of any single component score for the initial icatibant exposure. The investigator used a symptom score to assess the severities of symptoms of acute cutaneous, abdominal, and laryngeal attacks of hereditary angioedema (HAE) using the following 5-point scale: 0=none (absence of symptoms), 1=mild (no to mild interference with daily activities), 2=moderate (moderate interference with daily activities), 3=severe (severe interference with daily activities) and 4=very severe (very severe interference with daily activities). TOSR for participants who received initial icatibant administration was reported.

Time to Onset of Symptom Relief (TOSR) for Composite Investigator-Assessed Symptom Scores for Icatibant Exposure Number 2 and 3

The TOSR was defined as the duration of time in hours from study drug administration to the earliest time post-treatment at which there was at least a 20% improvement in the composite (or average) post-treatment symptom score with no worsening of any single component score. The investigator used a symptom score to assess the severities of symptoms of acute cutaneous, abdominal, and laryngeal attacks of HAE using the following 5-point scale: 0=none (absence of symptoms), 1=mild (no to mild interference with daily activities), 2=moderate (moderate interference with daily activities), 3=severe (severe interference with daily activities) and 4=very severe (very severe interference with daily activities). TOSR for participants who received subsequent icatibant administration by HCP administration or by caregiver/ self-administration was reported.

Time to Onset of Symptom Relief (TOSR) for Faces Pain Scale-Revised (FPS-R) Scores for Icatibant Exposure Number 1

The TOSR was defined as the earliest time at which the post-treatment score improved by at least one level. Participants of 4 years age and older self-assessed their HAE-related pain using the FPS-R instrument. FPS-R is a self-reported measure used to assess the intensity of children's pain and it is scored using a 0 to 10 scale (0=no pain to 10=very much pain). TOSR for participants who received initial icatibant administration was reported.

Time to Onset of Symptom Relief (TOSR) for Faces Pain Scale-Revised (FPS-R) Scores for Icatibant Exposure Number 2 and 3

The TOSR was defined as the earliest time at which the post-treatment score improved by at least one level. Participants of 4 years age and older self-assessed their HAE-related pain using the FPS-R instrument. FPS-R is a self-reported measure used to assess the intensity of children's pain and it is scored using a 0 to 10 scale (0=no pain to 10=very much pain). TOSR for participants who received subsequent icatibant administration by HCP administration or by caregiver/ self-administration was reported.

Time to Onset of Symptom Relief (TOSR) for Faces, Legs, Activity, Cry, and Consolability (FLACC) Scores

The TOSR was defined as the earliest time at which a 20% improvement was seen in the total post-treatment score. Participants of 4 years age and younger underwent investigator assessment of HAE-related pain (cutaneous, abdominal, and laryngeal) using the FLACC comportmental pain scale. Each of the 5 categories was scored from 0 to 2. Face(F): 0 (no particular expression/smile) - 2 (frequent to constant frown clenched jaw quivering chin); Legs(L): 0 (normal position/relaxed) - 2 (kicking/legs drawn up); Activity(A): 0 (lying quietly, normal position, moves easily) - 2 (arched rigid/jerking); Cry(C): 0 (No cry [awake/asleep]) - 2 (crying steadily/screams/sobs or frequent complaints); Consolability(C): 0 (content/relaxed) - 2 (difficult to console/comfort), resulting in a total score between 0 and 10.

Time to Minimum Symptoms for Composite Investigator-Assessed Symptom Scores for Icatibant Exposure Number 1

Time to minimum symptom was defined as the duration of time in hours from study drug administration to the earliest time post-treatment at which all symptoms were either mild or absent for the investigator-reported symptom score. The investigator used a symptom score to assess the severities of symptoms of acute cutaneous, abdominal, and laryngeal attacks of HAE using the following 5-point scale: 0=none (absence of symptoms), 1=mild (no to mild interference with daily activities), 2=moderate (moderate interference with daily activities), 3=severe (severe interference with daily activities) and 4=very severe (very severe interference with daily activities). Time to minimum symptom for participants who received initial icatibant administration was reported.

Time to Minimum Symptoms for Composite Investigator-Assessed Symptom Scores for Icatibant Exposure Number 2 and 3

Time to minimum symptom was defined as the duration of time in hours from study drug administration to the earliest time post-treatment at which all symptoms were either mild or absent for the investigator-reported symptom score. The investigator used a symptom score to assess the severities of symptoms of acute cutaneous, abdominal, and laryngeal attacks of HAE using the following 5-point scale: 0=none (absence of symptoms), 1=mild (no to mild interference with daily activities), 2=moderate (moderate interference with daily activities), 3=severe (severe interference with daily activities) and 4=very severe (very severe interference with daily activities). Time to minimum symptom for participants who received subsequent icatibant administration by HCP administration or by caregiver/ self-administration was reported.

Time to minimum symptoms was defined as the duration of time in hours from study drug administration to the earliest time at which post-treatment score improved to zero (or no pain). Participants of 4 years of age and older self-assessed their HAE-related pain using the FPS-R instrument. FPS-R is a self-reported measure used to assess the intensity of children's pain and it is scored using a 0 to 10 scale (0=no pain to 10=very much pain). Time to minimum symptom for participants who received initial icatibant administration was reported.

Time to Minimum Symptom for Faces Pain Scale-Revised (FPS-R) Scores for Icatibant Exposure Number 2 and 3

Time to minimum symptoms was defined as the duration of time in hours from study drug administration to the earliest time at which post-treatment score improved to zero (or no pain). Participants of 4 years of age and older self-assessed their HAE-related pain using the FPS-R instrument. FPS-R is a self-reported measure used to assess the intensity of children's pain and it is scored using a 0 to 10 scale (0=no pain to 10=very much pain). Time to minimum symptom for participants who received subsequent icatibant administration by HCP administration or by caregiver/ self-administration was reported.

Time to minimum symptoms was defined as the duration of time in hours from study drug administration to the earliest time at which the total post-treatment score improved to zero. Participants of 4 years age and younger underwent investigator assessment of HAE-related pain (cutaneous, abdominal, and laryngeal) using the FLACC comportmental pain scale. Each of the 5 categories was scored from 0 to 2. (F) Face: 0 (no particular expression/smile) - 2 (frequent to constant frown clenched jaw quivering chin); (L) Legs: 0 (normal position/relaxed) - 2 (kicking/legs drawn up); (A) Activity: 0 (lying quietly, normal position, moves easily) - 2 (arched rigid/jerking); (C) Cry: 0 (No cry [awake/asleep]) - 2 (crying steadily/screams/sobs or frequent complaints); (C) Consolability: 0 (content/relaxed) - 2 (difficult to console/comfort), resulting in a total score between 0 and 10.

Time to Use of Rescue Medication for the Treatment of Symptoms of the Hereditary Angioedema (HAE) Attack Following Study Drug Administration

Rescue medication was any medication used after the administration of icatibant which, in the opinion of the investigator, was immediately necessary to alleviate acute symptoms which are judged by the investigator as resultant from the current HAE attack. Time to first use of rescue medication prior to the onset of symptom relief was calculated from the time of study drug administration to the first use of rescue medication prior to the onset of symptom relief. This analysis was not performed since as per protocol, "This analysis will only be performed if there are at least 5 participants for a given attack who used rescue medication prior to attaining symptom relief".

Number of Participants With Worsened Intensity of Clinical Hereditary Angioedema (HAE) Symptoms Between 2 and 4 Hours After Treatment With Icatibant Exposure Number 1

The investigator used a symptom score to assess the severities of symptoms of acute cutaneous, abdominal, and laryngeal attacks of HAE using the following 5- point scale: 0=none (absence of symptoms), 1=mild (no to mild interference with daily activities), 2=moderate (moderate interference with daily activities), 3=severe (severe interference with daily activities) and 4=very severe (very severe interference with daily activities). The number of participants with a worsened severity of HAE symptoms at 4 hours post-dose from 2 hours postdose were reported.

Number of Participants With Worsened Intensity of Clinical Hereditary Angioedema (HAE) Symptoms Between 2 and 4 Hours After Treatment With Icatibant Exposure Number 2 and 3

The investigator used a symptom score to assess the severities of symptoms of acute cutaneous, abdominal, and laryngeal attacks of HAE using the following 5- point scale: 0=none (absence of symptoms), 1=mild (no to mild interference with daily activities), 2=moderate (moderate interference with daily activities), 3=severe (severe interference with daily activities) and 4=very severe (very severe interference with daily activities). The number of participants with a worsened severity of HAE symptoms at 4 hours post-dose from 2 hours post-dose were reported.

Inclusion Criteria: Two through <18 years of age at the time of first HAE attack. Prepubertal and pubertal/postpubertal subjects experiencing and acute cutaneous, abdominal, or laryngeal HAE attack treated with icatibant as part of this study. Pubertal/postpubertal subjects with HAE who are treated with icatibant, but not during an attack. Documented diagnosis of HAE Type I or II. Informed consent (and subject assent as appropriate) signed by the subject's parent(s)or legal guardian(s). Exclusion Criteria: Diagnosis of angioedema other than HAE. Participation in another clinical trial that involves the use of any investigational product (drug or device)within 30 days prior to study enrollment or at any time during the study. Any known factor/disease that might interfere with the treatment compliance, study conduct,or result interpretation. Congenital or acquired cardiac anomalies that interfere significantly with cardiac function. Treatment with ACE inhibitors within 7 days prior to treatment. Use of hormonal contraception within the 90 days prior to treatment. Androgen use (eg, stanozolol, danazol, oxandrolone, methyltestosterone, testosterone) within the 90 days prior to treatment. Pregnancy or breastfeeding. A physical condition that interferes with pubertal status determination.

Takeda provides access to the de-identified individual participant data (IPD) for eligible studies to aid qualified researchers in addressing legitimate scientific objectives (Takeda's data sharing commitment is available on https://clinicaltrials.takeda.com/takedas-commitment?commitment=5). These IPDs will be provided in a secure research environment following approval of a data sharing request, and under the terms of a data sharing agreement.

IPD from eligible studies will be shared with qualified researchers according to the criteria and process described on https://vivli.org/ourmember/takeda/. For approved requests, the researchers will be provided access to anonymized data (to respect patient privacy in line with applicable laws and regulations) and with information necessary to address the research objectives under the terms of a data sharing agreement.

Farkas H, Reshef A, Aberer W, Caballero T, McCarthy L, Hao J, Nothaft W, Schranz J, Bernstein JA, Li HH. Treatment Effect and Safety of Icatibant in Pediatric Patients with Hereditary Angioedema. J Allergy Clin Immunol Pract. 2017 Nov-Dec;5(6):1671-1678.e2. doi: 10.1016/j.jaip.2017.04.010. Epub 2017 Jun 7.