Fabry Disease
Conditions
Keywords
Lysosomes, Storage, Glycolipid, Fabry disease, Stroke, Children, Pediatrics
Brief summary
Primary Objective(s): * To assess the safety of Replagal at a dose of 0.2 mg/kg administered over 40 (+/-10) minutes in children with Fabry disease * To assess the effect of Replagal on heart rate variability in patients 7 to 17 years of age Secondary Objective(s): * To determine the pharmacokinetics of Replagal at baseline and after the initiation of enzyme replacement therapy (ERT) * To determine exploratory measurements of efficacy including renal function (ie, estimated glomerular filtration rate \[eGFR\] and creatinine clearance), clinical outcomes (in Cohorts 1 and 2), and sweating and left ventricular mass index (LVMI) (Cohort 1, Phase 1 only)
Detailed description
TKT029 is an open label multi-center study to assess the safety of enzyme replacement therapy with Replagal (agalsidase alfa) in children with Fabry disease, who have completed 6 months of agalsidase alfa therapy in study TKT023 (Cohort 1) or who are treatment-naïve (Cohort 2) and meet all inclusion/exclusion criteria of this study. The study will consist of every other week treatment with Replagal for 52 weeks, with periodic reassessments by Shire HGT for continuation of the study beyond 52 weeks. A decision on the part of the study sponsor to terminate the study may be made at any time. In Cohort 1, safety and clinical measurement assessments performed during Week 25 or 26 of Study TKT023 served as the baseline assessments for TKT029. Patients in Cohort 1 began treatment with Replagal manufactured using a roller bottle process (Replagal RB); this portion of treatment is denoted as Cohort 1, Phase 1. Safety evaluation visits for Cohort 1, Phase 1 were to be performed at Weeks 13, 25, 55, and every 26 weeks thereafter until the patient discontinued from the study or transitioned to treatment with Replagal manufactured using a bioreactor process (Replagal AF). The transition to Replagal AF marked the restart of the study clock and was denoted as Cohort 1, Phase 2. Safety evaluation visits for Cohort 1, Phase 2 will be performed at Weeks 1, 13, 25, 55, and every 26 weeks thereafter until the patient discontinues from or the sponsor terminates the study. Patients in Cohort 2 will receive treatment with Replagal AF only; therefore there is only 1 study phase for these patients. Screening assessments performed at Week -1 will serve as the baseline assessments for this study. Safety evaluation visits for Cohort 2 will be performed at Weeks 13, 25, 37, 55 and every 26 weeks thereafter until the patients discontinues from or the sponsor terminates the study. The final study visit for both cohorts will follow 30 days after the study study drug infusion, at which time a final safety evaluation will be performed. Patients who complete the study will be interviewed by telephone 30 days after their last study infusion for resolution of any outstanding adverse events (AEs) or concomitant medication changes. Any patient who withdraws early from the study will have a final study visit 30 days after the last study drug infusion, at which time a final safety evaluation will be performed.
Interventions
0.2 mg/kg agalsidase alfa administered by IV infusion over 40 (+/- 10) minutes every other week for 52 weeks, with periodic reassessments for study continuation beyond 52 weeks
Sponsors
Study design
Eligibility
Inclusion criteria
1a. For Cohort 1 (both phases): \- Patients must have completed all study requirements and assessments for Study TKT023 less than 30 (+/-7) days prior to enrolling in Study TKT029 and must have no safety or medical issues that contraindicate participation. OR 1b. For Cohort 2: * The patient is between 7 and 17 years of age at the time of informed consent, inclusive. * The patient must be ERT-naive. * The patient is a hemizygous male with Fabry disease as confirmed by a deficiency of alpha-galactosidase A activity measured in serum, leukocytes, or fibroblasts. Male patients who do not already have a documented deficiency of alpha-galactosidase A activity will provide a blood sample during screening for determination of alpha-galactosidase A activity level in their serum. OR \- The patient is a heterozygous female or hemizygous male with Fabry disease as confirmed by a mutation of the alpha-galactosidase A gene. Patients who do not already have a documented mutation of the alpha-galactosidase A gene will provide a blood sample during screening for genotyping. 2\. Adequate general health (as determined by the Investigators) to undergo the specified phlebotomy regimen and protocol-related procedures and no safety or medical contraindications for participation. 3\. The minor child must assent to participate in the protocol and the parent(s) or legally authorized guardian(s) must have voluntarily signed an Institutional Review Board/Independent Ethics Committee (IRB/IEC) approved informed concent form after all relevant aspects of the study have been explained and discussed with the child and the child's parent(s) or legal guardian(s).
Exclusion criteria
Patients who meet any of the following criteria are not eligible for this study: * Patient and/or the patient's parent(s) or legal guardian(s) are unable to understand the nature, scope, and possible consequences of the study. * Patient is unable to comply with the protocol, e.g., uncooperative with protocol schedule, refusal to agree to all of the study procedures, inability to return for safety evaluations, or is otherwise unlikely to complete the study, as determined by the Investigator or the medical monitor.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Patients Who Experienced At Least One Adverse Event (AE) | 362 weeks |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 81 | Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours. | AUC0-∞ is a measure of the total exposure to a drug. |
| Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 133 | Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours. | AUC0-∞ is a measure of the total exposure to a drug. |
| Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 159 | Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours. | AUC0-∞ is a measure of the total exposure to a drug. |
| Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 315/341 | Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours. | AUC0-∞ is a measure of the total exposure to a drug. |
| Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 133 | Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours. | Cmax is the peak plasma concentration of a drug after administration. |
| Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 159 | Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours. | Cmax is the peak plasma concentration of a drug after administration. |
| Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 315/341 | Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours. | Cmax is the peak plasma concentration of a drug after administration. |
| Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 81 | Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours. | Cmax is the peak plasma concentration of a drug after administration. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Heart Rate Variability - Change From Baseline at Week 185 in SDNN | Week 185 | Heart rate variability was assessed by 2-hour Holter monitoring. Standard deviation of all filtered RR intervals over the length of the analysis (SDNN) was measured. |
Countries
Canada, United States
Participant flow
Pre-assignment details
No patient was enrolled in Cohort 2 (ie, no treatment-naive patients were enrolled).
Participants by arm
| Arm | Count |
|---|---|
| Agalsidase Alfa (Cohort 1) 0.2 mg/kg agalsidase alfa infused by IV over 40 (+/- 10) minutes every other week | 17 |
| Total | 17 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Phase 1 (Treatment With Replagal RB) | Lost to Follow-up | 1 |
| Phase 2 (Transition to Replagal AF) | Failure to visit clinic as scheduled | 1 |
Baseline characteristics
| Characteristic | Agalsidase Alfa (Cohort 1) |
|---|---|
| Age, Continuous | 11.99 years STANDARD_DEVIATION 3.2464 |
| Baseline Heart Rate Variability (SDNN) | 98.947 msec STANDARD_DEVIATION 32.324 |
| Race/Ethnicity, Customized Hispanic | 2 Participants |
| Race/Ethnicity, Customized White | 15 Participants |
| Sex: Female, Male Female | 1 Participants |
| Sex: Female, Male Male | 16 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 17 / 17 | 11 / 11 |
| serious Total, serious adverse events | 2 / 17 | 2 / 11 |
Outcome results
Patients Who Experienced At Least One Adverse Event (AE)
Time frame: 362 weeks
Population: Safety Population: Patients in Cohort 1 who received at least one dose of Replagal RB in Phase 1.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Agalsidase Alfa (Cohort 1) | Patients Who Experienced At Least One Adverse Event (AE) | 17 participants |
Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 133
AUC0-∞ is a measure of the total exposure to a drug.
Time frame: Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours.
Population: PK Population: All patients who received at least 1 dose of Replagal (RB or AF) and had at least 1 PK sample drawn.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 133 | 295779 min·U/mL | Standard Deviation 161058 |
Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 159
AUC0-∞ is a measure of the total exposure to a drug.
Time frame: Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours.
Population: PK Population: All patients who received at least 1 dose of Replagal (RB or AF) and had at least 1 PK sample drawn.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 159 | 218078 min·U/mL | Standard Deviation 73560 |
Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 315/341
AUC0-∞ is a measure of the total exposure to a drug.
Time frame: Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours.
Population: PK Population: All patients who received at least 1 dose of Replagal (RB or AF) and had at least 1 PK sample drawn.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 315/341 | 213193 min·U/mL | Standard Deviation 119581 |
Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 81
AUC0-∞ is a measure of the total exposure to a drug.
Time frame: Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours.
Population: PK Population: All patients who received at least 1 dose of Replagal (RB or AF) and had at least 1 PK sample drawn.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Pharmacokinetics - Area Under the Serum Concentration-Time Curve (AUC0-∞) - Week 81 | 245282 min·U/mL | Standard Deviation 159071 |
Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 133
Cmax is the peak plasma concentration of a drug after administration.
Time frame: Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 133 | 3842 U/mL | Standard Deviation 1235 |
Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 159
Cmax is the peak plasma concentration of a drug after administration.
Time frame: Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 159 | 3842 U/mL | Standard Deviation 1235 |
Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 315/341
Cmax is the peak plasma concentration of a drug after administration.
Time frame: Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 315/341 | 3568 U/mL | Standard Deviation 1492 |
Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 81
Cmax is the peak plasma concentration of a drug after administration.
Time frame: Pre-infusion; and post-infusion at 20, 40, 50, 60, 90 minutes, and 2, 3, 4, 8 hours.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Pharmacokinetics - Maximum Observed Serum Concentration (Cmax) - Week 81 | 3173 U/mL | Standard Deviation 969 |
Heart Rate Variability - Change From Baseline at Week 185 in SDNN
Heart rate variability was assessed by 2-hour Holter monitoring. Standard deviation of all filtered RR intervals over the length of the analysis (SDNN) was measured.
Time frame: Week 185
Population: Number of participants present at Visit Week 185 included for analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Agalsidase Alfa (Cohort 1) | Heart Rate Variability - Change From Baseline at Week 185 in SDNN | 20.256 msec | Standard Deviation 29.06 |