A Study to Assess the Efficacy, Safety and Pharmacokinetics of Nusinersen (ISIS 396443) in Infants With Spinal Muscular Atrophy (SMA)

Biogen21 enrolled

Overview

The primary objective is to examine the clinical efficacy of multiple doses of nusinersen (ISIS 396443) administered intrathecally to participants with Infantile-Onset Spinal Muscular Atrophy (SMA). The secondary objectives are to examine the safety and tolerability of multiple doses of nusinersen administered intrathecally to participants with infantile-onset SMA and to examine the cerebral spinal fluid (CSF) and plasma Pharmacokinetics (PK) of multiple doses of nusinersen administered intrathecally to participants with infantile-onset SMA.

This study was conducted and the protocol was registered by Ionis Pharmaceuticals, Inc.. In August 2016, sponsorship of the trial was transferred to Biogen.

Study Type

INTERVENTIONAL

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Spinal Muscular Atrophy

Interventions

Eligibility

Sex: ALLMin age: 21 DaysMax age: 210 Days

Medical Language ↔ Plain English

Key Inclusion Criteria: * Genetic documentation of 5q SMA (homozygous gene deletion or mutation) * Onset of clinical signs and symptoms consistent with SMA at ≥ 21 days and \<6 months (180 days) of age * At study entry, receiving adequate nutrition and hydration (with or without gastrostomy), in the opinion of the Site Investigator * Body weight \>5th percentile for age using Center of Disease Control and Prevention (CDC) guidelines * Medical care meets and is expected to continue to meet guidelines set out in the Consensus Statement for Standard of Care in SMA (Wang et al. 2007), in the opinion of the Site Investigator * Gestational age of 35 to 42 weeks and gestation body weight ≥2 kg * Reside within approximately 9 hours ground-travel distance from a participating study center for the duration of the study. Residence \>2 hours ground-travel distance from a study center must obtain clearance from the Site Investigator and the study Medical Monitor * Able to complete all study procedures, measurements and visits and parent or guardian/participant has adequately supportive psychosocial circumstances, in the opinion of the Site Investigator Exclusion Criteria: * Hypoxemia (O2 saturation awake \<96% or O2 saturation asleep \<96%, without ventilation support) * Presence of an untreated or inadequately treated active infection requiring systemic antiviral or antimicrobial therapy at any time during the screening period * History of brain or spinal cord disease that would interfere with the lumbar puncture (LP) procedures, CSF circulation, or safety assessments * Presence of an implanted shunt for the drainage of cerebrospinal fluid (CSF) or an implanted central nervous system (CNS) catheter * History of bacterial meningitis * Clinically significant abnormalities in hematology or clinical chemistry parameters, as assessed by the Site Investigator, at screening that would render the participant unsuitable for inclusion * Treatment with another investigational drug (e.g., albuterol, riluzole, carnitine, creatine, sodium phenylbutyrate, salbutamol, valproate, hydroxyurea etc), biological agent, or device within 90 days prior to enrollment or anytime during the study. Any history of gene therapy or cell transplantation * The participants parent(s) or legal guardian(s) is unable to understand the nature, scope, and possible consequences of the study, or does not agree to comply with the protocol defined schedule of assessments * Ongoing medical condition that according to the Site Investigator would interfere with the conduct and assessments of the study. Examples are medical disability other than SMA that would interfere with the assessment of safety or would compromise the ability of the participant to undergo study procedures NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

Locations (4)

Stanford University Medical Center

Stanford, California, United States

Nemours Children's Hospital

Orlando, Florida, United States

Columbia University Medical Center

New York, New York, United States

The Hospital for Sick Children (SickKids)

Toronto, Ontario, Canada

Outcomes

Primary Outcomes

Percent of Participants Who Achieved Improvement in Motor Milestones as Assessed by Section 2 of the HINE at the Last Visit

Section 2 of HINE consists of 8 independent milestone categories. Within each of these categories, participants can progress from complete absence of a motor ability (the lowest level in each category) through multiple milestones (2 to 4 levels in each category) to the highest level within the category. Overall, there are a total of 26 milestones that can be achieved across the 8 categories. Improvement was defined as any of the following: 1. An increase from baseline of 2 milestones or more, or the achievement of pincer grasp in the voluntary grasp category 2. An increase from baseline of 2 milestones or more, or achievement of touching toes in the ability to kick category 3. An increase from baseline of 1 milestone or more in any of the remaining 6 categories: head control, rolling, sitting, crawling, standing, or walking.

Time frame: Day 1352 or Early Termination

Secondary Outcomes

Event-free Survival at the End of Study

Event-free survival was defined as the percent of participants who were alive and did not require permanent ventilatory support (defined as tracheostomy or the need for ≥16 hours ventilation/day continuously for at least 2 weeks in the absence of an acute reversible illness) Event-free survival was estimated using Kaplan-Meier methodology.

Time frame: Up to Day 1638

Percent of Participants With Improved Motor Function at the Last Visit as Assessed by the CHOP-INTEND Motor Function Scale

The CHOP-INTEND test includes 16 items structured to move from easiest to hardest with the grading including gravity eliminated (lower scores) to antigravity movements (higher scores). All item scores range from 0 (worst) to 4 (best). Total scores range from 0 to 64, with higher scores indicating better movement functioning. Improvement was defined as an increase in total CHOP INTEND score ≥4 points from baseline as of the last study visit.

Time frame: Day 1352 or Early Termination

Change in Neuromuscular Electrophysiology at the Last Visit as Assessed by the Change From Baseline in CMAP Amplitude

CMAP is an electrophysiological technique that can be used to determine the approximate number of motor neurons in a muscle or group of muscles. A positive change from Baseline indicates that the number of motor neurons increased.

Time frame: Baseline, Day 1072

Number of Participants Experiencing Adverse Events (AEs) and/or Serious Adverse Events (SAEs)

AE: any unfavorable and unintended sign, symptom, or disease temporally associated with the study or use of investigational drug product, whether or not the AE is considered related to the investigational drug product. SAE: any AE that in the view of either the Investigator or Sponsor, meets any of the following criteria: results in death; is life threatening: that is, poses an immediate risk of death at the time of the event; requires in-patient hospitalization or prolongation of existing hospitalization; results in a persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions; results in congenital anomaly or birth defect in the offspring of the subject (whether male or female); is an important medical event in the opinion of the Investigator or Sponsor.

Time frame: Up to Day 1352

Concentration of Nusinersen in Cerebrospinal Fluid (CSF)

The concentration of nusinersen in CSF was measured by using standard laboratory assays.

Time frame: Day 1135 (Predose)

PK Parameters of Nusinersen in Plasma: Maximum Concentration (Cmax)

Cmax is the maximum observed concentration of study drug in plasma.

Time frame: Day 1 (Predose and 1, 2, and 4 hours [hr] Postdose) and Day 2 (24 hr Postdose )

PK Parameters of Nusinersen in Plasma: Time to Reach Cmax (Tmax)

Tmax is the time at which Cmax occurs.

Time frame: Day 1 (Predose and 1, 2, and 4 hours [hr] Postdose) and Day 2 (24 hr Postdose )

PK Parameters of Nusinersen in Plasma: Area Under the Plasma Concentrations Time Curve From the Time of the IT Dose to Four Hours After Dosing (AUC0-4)

AUC is area under the plasma concentration-time curve from zero time (Predose) to 4 hours after IT administration of study drug. AUC was determined by using the linear trapezoidal rule.

Time frame: Day 1 (Predose and 1, 2, and 4 hours [hr] Postdose) and Day 2 (24 hr Postdose )