Title
Phase I/II Study of SRP-4053 in DMD Patients
A 2-Part, Randomized, Double-Blind, Placebo-Controlled, Dose-Titration, Safety, Tolerability, and Pharmacokinetics Study (Part 1) Followed by an Open-Label Efficacy and Safety Evaluation (Part 2) of SRP-4053 in Patients With Duchenne Muscular Dystrophy Amenable to Exon 53 Skipping
Phase
Phase 1/Phase 2Lead Sponsor
Sarepta TherapeuticsStudy Type
InterventionalStatus
Completed Results PostedIndication/Condition
Duchenne Muscular DystrophyIntervention/Treatment
golodirsen ...Study Participants
39This is a first-in-human, multiple-dose 2-part study to assess the safety, tolerability, efficacy, and pharmacokinetics of SRP-4053 in Duchenne muscular dystrophy (DMD) patients with deletions amenable to exon 53 skipping.
Part 1: Randomized, placebo-controlled dose-titration to assess safety, tolerability and pharmacokinetics of 4 dose levels of SRP-4053 in genotypically-confirmed DMD patients with deletions amenable to exon 53 skipping.
Part 2: Open-label evaluation of SRP-4053 in patients from Part 1, along with newly enrolled DMD patients with deletions amenable to exon 53 skipping and an untreated group of DMD patients with deletions not amenable to exon 53 skipping.
Safety, including adverse event monitoring and routine laboratory assessments, will be followed on an ongoing basis for all patients.
Clinical efficacy, including functional tests such as the six-minute walk test (6MWT), will be assessed at regularly scheduled study visits. Patients in the treated groups will undergo one baseline and one follow-up muscle biopsy. Patients in the untreated group will not undergo biopsies and will follow an abbreviated schedule of study assessments.
SRP-4053 placebo-matching solution for IV infusion.
SRP-4053 (golodirsen) solution for IV infusion.
Patients will receive SRP-4053 (golodirsen) intravenous (IV) infusions, weekly, at escalating dose levels as follows: Weeks 1-2, 4 mg/kg/week; Weeks 3-4, 10 mg/kg/week; Weeks 5-6, 20 mg/kg/week; Weeks 7-12, 30 mg/kg/week. Dosing will be interrupted or halted if specific predefined stopping criteria are met or if warranted at the discretion of the Sponsor or Investigator.
Patients will receive SRP-4053 placebo-matching IV infusions, weekly, for 12 weeks. Dosing will be interrupted or halted if specific predefined stopping criteria are met or if warranted at the discretion of the Sponsor or Investigator.
All eligible patients from Part 1, as well as new patients, will receive SRP-4053 (golodirsen) 30 mg/kg/week IV infusions, weekly, for up to 168 weeks.
Patients with DMD who have a genotypically confirmed deletion of exon(s) not amenable to treatment by exon 53 skipping, but who otherwise meet the same eligibility criteria as treated patients newly recruited to Part 2, will undergo the same study assessments as treated Patients (except for pharmacokinetic [PK] sampling and muscle biopsies), but at a reduced schedule through Week 144. The untreated patients are not considered as control group.
Inclusion Criteria: Diagnosed with DMD, genotypically confirmed. Intact right and left biceps muscles or an alternative upper arm muscle group. Stable pulmonary and cardiac function. Minimum performance on 6MWT, North Star Ambulatory Assessment, and rise (Gowers) test as specified in the study protocol. On a stable dose of corticosteroids for at least 6 months. Exclusion Criteria: Previous treatment with the experimental agents BMN-195 (SMT C1100) or PRO053. Current or previous treatment with any other experimental treatments within 12 weeks prior to study entry. Major surgery within the last 3 months. Presence of other clinically significant illness. Major change in physical therapy regime within the last 3 months. Other inclusion and exclusion criteria may apply.
| Event Type | Organ System | Event Term | Part 1: Placebo | Part 1: Golodirsen (4 mg/kg) | Part 1: Golodirsen (10 mg/kg) | Part 1: Golodirsen (20 mg/kg) | Part 1: Golodirsen (30 mg/kg) | Part 2a: Total Golodirsen Group | Part 2b: Untreated Group (Natural History of Non-exon 53) |
|---|
Twelve-lead ECGs were performed at a consistent time of day throughout the study. Electrocardiograms were performed only after the participant was in the supine position, resting, and quiet for a minimum of 15 minutes. The ECG was manually reviewed and interpreted by medically qualified personnel. Number of participants with potentially clinically significant abnormalities in ECG reported as TEAEs presented here. The Investigator determined whether abnormal assessment results were potentially clinically significant or not.
Standard, 2-dimensional ECHOs were performed at a consistent time of day throughout the study. Cardiac function events included cardiomegaly, tachycardia, and dyspnoea. The ECHO was reviewed and interpreted by medically qualified personnel. Number of participants with potentially clinically significant abnormalities in ECHO were reported.
6MWT was performed by standardized procedures for all participants. Participants were asked to walk a set course of 25 meters for 6 minutes (timed), and the distance walked (in meters) was recorded. Change from baseline in 6MWT distance at Week 144 in total golodirsen group was reported.
6MWT was performed by standardized procedures for all participants. Participants were asked to walk a set course of 25 meters for 6 minutes (timed), and the distance walked (in meters) was recorded. Change from baseline in 6MWT distance at Week 144 in untreated group (non-exon 53 amenable participants) was calculated.
Change from baseline in dystrophin protein levels (in muscle biopsy samples) was determined by Western blot in total golodirsen group.
Vital sign parameters included systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and body temperature. Number of participants with at least one potentially clinically significant abnormal vital signs findings were reported as TEAEs. The Investigator determined whether abnormal assessment results were potentially clinically significant or not. Potential clinical significance was defined as any variation in assessment results that had medical relevance resulting in an alteration in medical care.
Physical examinations were performed by the Investigator, or qualified study staff. A full physical examination included a review of general appearance, head, eyes, ears, nose and throat, heart, lungs, abdomen, extremities, skin, lymph nodes, musculoskeletal, and neurological systems. Number of participants with potentially clinically significant abnormalities in physical examinations were reported. Potentially clinically significant abnormalities in physical examinations were based on Investigator's discretion.
Laboratory parameters included hematology, serum chemistry (SC), urinalysis and coagulation. Number of participants with at least one potentially clinically significant abnormal finding were reported as TEAEs. The Investigator determined whether abnormal assessment results were potentially clinically significant or not. Potentially clinical significance was defined as any variation in assessment results that had medical relevance resulting in an alteration in medical care.
Adverse event (AE) was any untoward medical occurrence in a clinical trial participant, which does not necessarily have a causal relationship with the investigational drug. A Serious adverse event (SAE) was an AE resulting in any of the following outcomes: death; Life-threatening event; Required or prolonged inpatient hospitalization; persistent or significant disability/incapacity; congenital anomaly. TEAEs were defined as AEs that were reported or worsened on or after the start of study drug dosing through 12 weeks. TEAEs included both Serious TEAEs and non-serious TEAEs.
FVC was the total amount of air exhaled during the forced expiratory volume test that was measured during spirometry and the most important measurement of lung function. This test required participant to breath into a tube connected to a machine that measures the amount of air that can be moved in and out of the lungs after taking an inhaled bronchodilator medicine which was used to dilate participant bronchial (breathing) tubes. Percent of predicted FVC = (observed value)/ (predicted value) * 100%.
FVC was the total amount of air exhaled during the forced expiratory volume test that was measured during spirometry and is the most important measurement of lung function. This test requires participant to breath into a tube connected to a machine that measures the amount of air that can be moved in and out of the lungs after taking an inhaled bronchodilator medicine which was used to dilate participant bronchial (breathing) tubes. Percent of predicted FVC = (observed value)/ (predicted value) * 100%.
Change from baseline in dystrophin Intensity levels (in muscle biopsy samples) was determined by Immunohistochemistry in total golodirsen group.
Percent change from baseline in Exon 53 skipping (in muscle biopsy samples) was determined by reverse transcription polymerase chain reaction in total golodirsen group.
Percent change from baseline in dystrophin positive fibers (in muscle biopsy samples) were determined by Immunohistochemistry at Week 48 in total golodirsen group.
Drug clearance is a quantitative measure of the rate at which a drug substance is removed from the blood.
Maximum Concentration (Cmax) of golodirsen in plasma was evaluated.
Time to reach maximum plasma concentration (Tmax) of golodirsen was evaluated.
Area under the concentration-time curve from time zero extrapolated to the infinity was evaluated.
Volume of distribution was defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired plasma concentration of a drug. Apparent volume of distribution at steady state of golodirsen was evaluated.
T1/2 is the time measured for the plasma concentration of drug to decrease by one half. T1/2 of golodirsen was evaluated.
MRT= AUMCinf/AUCinf, where AUMCinf is the area under the first moment curve from time 0 extrapolated to infinite time, calculated using the linear/log trapezoidal method. Mean residence time of golodirsen was evaluated.
Renal clearance was calculated using the partial AUC0-24 from the non-compartmental analysis in plasma and AE0-24. AUC0-24 was defined as area under the plasma concentration-time curve, from time 0 to 24 hours after completion of dosing. AE0-24 was defined as total cumulative amount excreted from 0 to 24 hours. Summarized data of all urine collection intervals are reported.
