A Study to Find Out How Nusinersen is Processed in the Body When Given Through the ThecaFlex DRx™ System in Adult and Pediatric Participants With Spinal Muscular Atrophy (PIERRE-PK)

Official title

An Open Label, Single Cohort Study to Assess the Pharmacokinetic Profile of Nusinersen (BIIB058) Administered Via the ThecaFlex DRx™ System (PIERRE-PK)

Overview

In this PIERRE-PK study, researchers will learn how the body processes nusinersen when it is given through the ThecaFlex DRx™ System, compared to when nusinersen is given by lumbar puncture (LP). The ThecaFlex DRx system is an investigational implantable medical device developed by Alcyone Therapeutics, Inc. It consists of a catheter, which is a flexible tube, connected to a port which is placed under the skin. Alcyone Therapeutics, Inc. has an ongoing study called PIERRE to test the ThecaFlex DRx system. Participants with spinal muscular atrophy (SMA) in the PIERRE study may be enrolled in the PIERRE-PK study. The main objective of the PIERRE-PK study is to learn how the body processes nusinersen when given by the ThecaFlex DRx system compared to a lumbar puncture. The main questions researchers want to answer are: * What is the highest amount of nusinersen found in the blood after dosing? * How much nusinersen is found in the blood over the first 24 hours after dosing? The PIERRE-PK study will be done as follows: * Participants will be screened to check if they can join the study. The screening period will be up to 30 days for this study and may overlap with the PIERRE study. * Participants will receive a dose of nusinersen by lumbar puncture. * The ThecaFlex DRx system will be implanted after the lumbar puncture, as part of the PIERRE study. * Participants will receive a dose of nusinersen by the ThecaFlex DRx system, as part of the PIERRE study. * Researchers will take blood samples before and after each dose. The last blood sample will be taken 24 hours after the dose. * The total study duration for each participant in the PIERRE-PK study will be approximately 5 months. This period will overlap with the participant's first 5 months in the PIERRE study.

Detailed description

The primary objective of this study is to assess the Pharmacokinetic (PK) profile of nusinersen delivered via standard LP and via the ThecaFlex DRx System in participants with SMA.

Interventions

• Drug Nusinersen
  Administered as specified in the treatment arm.
• Device ThecaFlex DRx System
  Implanted as specified in the treatment arm.

Primary outcome measures

• Maximum Observed Concentration (Cmax) of Nusinersen Delivered via Standard LP and via ThecaFlex DRx System [Time frame: Pre-dose and at multiple time points post-dose up to 4 months]
• Area Under the Plasma Concentration-Time Curve From Zero Time to 24 Hours After Intrathecal Administration (AUC0-24h) of Nusinersen Delivered via Standard LP and via ThecaFlex DRx System [Time frame: Pre-dose and at multiple time points post-dose up to 4 months]

Eligibility criteria

Inclusion criteria

• Participant is on regular maintenance dosing of nusinersen (12 milligrams \[mg\] dose) every 4 months, with 4 months (± 2 weeks) between the LP-delivered study dose and the last nusinersen dose prior to study enrollment.
• Participants must be enrolled in the PIERRE study to be eligible for enrolment in the PIERRE PK study.

Exclusion criteria

• Ongoing participation or participation within 6 months or 5 half-lives of the agent (whichever is longer) of enrollment in other interventional clinical trials for the treatment of SMA (except for the PIERRE study or interventional clinical trials of myostatin inhibitors \[e.g., apitegromab and taldefgrobep alfa\]).
• Participant is naïve to nusinersen treatment.
• Participant is receiving nusinersen at a dose other than 12 mg.
• Participant has already undergone implantation of the ThecaFlex DRx system.
• Participant is pregnant, currently breastfeeding, or intending to become pregnant during the study.

NOTE: Other protocol-defined Inclusion/Exclusion criteria may apply

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Treatment

Study locations

United States · 10 centers

• Children's Hospital of Orange County — Orange
• Stanford University Medical Center | Department of Neurology_Palo Alto — Palo Alto
• Ann & Robert H. Lurie Children's Hospital of Chicago — Chicago
• Boston Children's Hospital — Boston
• Helen DeVos Children's Hospita — Grand Rapids
• Milton S. Hershey Medical Center | Pennsylvania State University_Hershey — Hershey
• Children's Hospital of Philadelphia — Philadelphia
• Texas Childrens Hospital Houston — Houston
• … and 2 more centers

Italy · 2 centers

• Fondazione Serena Onlus - Centro Clinico Nemo_Milano — Milan
• Fondazione Policlinico Universitario Agostino Gemelli IRCCS — Roma

Poland · 2 centers

• Szpital Specjalistyczny im. L.Rydygiera w Krakowie — Krakow
• Instytut Centrum Zdrowia Matki Polki — Lodz

Spain · 2 centers

• Hospital Universitario La Paz — Madrid
• Hospital Universitari i Politecnic La Fe_Valencia — Valencia

France · 1 center

• Hôpital Raymond Poincaré — Garches

Germany · 1 center

• Universitaetsklinikum Essen — Essen

United Kingdom · 1 center

• Royal Hallamshire Hospital Neurology Department — Sheffield

Identifiers

NCT: NCT06555419 · 295SM101 · 2024-514239-21-00

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗