A Study of Nusinersen Among Participants With Spinal Muscular Atrophy Who Received Onasemnogene Abeparvovec (RESPOND)

Biogen

Status and phase: Active, not recruiting; Phase 4

Conditions: Muscular Atrophy, Spinal

Treatments: Drug: Nusinersen

Study type: Interventional

Funder types: Industry

Identifiers

NCT04488133

2020-003492-18 (EudraCT Number)

232SM404

2023-505640-18 (Other Identifier)

Details and patient eligibility

About

The primary objective of this study is to evaluate the clinical outcomes following treatment with nusinersen in participants with spinal muscular atrophy (SMA) who previously received onasemnogene abeparvovec.

The secondary objectives of this study are to evaluate the safety and tolerability; clinical outcomes and pharmacodynamics (PD) of nusinersen treatment in participants with SMA who previously received onasemnogene abeparvovec.

Enrollment: 46 patients

Sex: All

Ages: 2 to 36 months old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Key Inclusion Criteria:

For all participants:

• Genetic documentation of 5q SMA homozygous gene survival motor neuron 1 (SMN1) deletion or mutation, or compound heterozygous mutation
• SMN2 copy number of ≥1
• ≤36 months of age at the time of first Nusinersen dose
• Must have previously received onasemnogene abeparvovec per the approved label or local/regional regulations ≥2 months prior to first Nusinersen dose
• Must have suboptimal clinical status per the Investigator

Additional Criteria for Subgroups A and B:

• <300 days of age at the time of first Nusinersen dose
• SMN2 copy number of 2

Additional Criteria for Subgroup A:

• SMA symptom onset ≤4 months (120 days) of age
• Must have received intravenous (IV) onasemnogene abeparvovec at >6 weeks to ≤6 months (43 days to 180 days) of age
• Must have received IV onasemnogene abeparvovec after SMA symptom onset

Additional Criteria for Subgroup B:

• Must have received IV onasemnogene abeparvovec at ≤6 weeks (42 days) of age

Key Exclusion Criteria:

For all participants:

• Prior exposure to Nusinersen
• Ongoing severe or serious AEs related to onasemnogene abeparvovec
• Treatment with an investigational drug, biological agent, or device within 30 days or 5 half-lives of the agent, whichever is longer, prior to study; any prior or current treatment with any survival motor neuron 2 (SMN2)-directed splicing modifier; prior antisense oligonucleotide treatment or cell transplantation; gene therapy for the treatment of SMA other than onasemnogene abeparvovec. Note: treatment with onasemnogene abeparvovec as part of an investigational study is allowed

Additional Criteria for Subgroups A and B:

• Weight-for-age is below the third percentile, based on WHO Child Growth Standards at the time of receiving onasemnogene abeparvovec. Adjustments for the gestational weight of premature babies enrolled in Subgroups A and B are allowed provided IV onasemnogene abeparvovec was dosed per the approved label or per local/regional regulations.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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46 participants in 1 patient group

Nusinersen 12 mg

Experimental group

Description:

Participants will receive Nusinersen 12 milligrams (mg) via intrathecal (IT) injection as loading doses on Days 1, 15, 29, and 64 followed by maintenance doses, every 4 months, on Days 183, 302, 421, 540 and 659.

Treatment:

Drug: Nusinersen