Study of Safety, Tolerability and Efficacy of GB221 in Infants With Spinal Muscular Atrophy Type 1

Plain-language summary

This study investigates the safety, tolerability, and effectiveness of an experimental treatment called GB221 in infants with spinal muscular atrophy type 1 (a severe inherited disease affecting the muscles). It can include infants who have biallelic SMN1 mutations and a limited number of SMN2 copies, whether they already have symptoms or are still presymptomatic. The study is in Phase 1/Phase 2 and is currently recruiting participants.

The summary above is a plain-language rendering of the official record. The original English title is shown for reference.

Trial details

Phase

PHASE1/PHASE2

Status

Recruiting

Sponsor

Gemma Biotherapeutics

Intervention

GB221

Start date

1/6/2026

Estimated completion

4/1/2029

Countries

Brazil

Related genes

Locations

• Porto Alegre, Brazil

Eligibility criteria

Criteria are reproduced from the ClinicalTrials.gov record in the original English. Only the trial team can determine eligibility.

Inclusion Criteria:

* Symptomatic Participants

  1. Diagnosis of SMA Type 1 based on gene mutation analysis with bi-allelic SMN1 mutations (deletion or point mutations) and up to 3 copies of SMN2
  2. Participants must be 2 weeks to \< 12 months of age at the time of dosing with disease onset of during the first 6 months of life.
* Presymptomatic Participants

  1. At risk of SMA Type 1 based on gene mutation analysis with bi-allelic SMN1 mutations (deletion or point mutations) and up to 2 copies of SMN2
  2. Participants must be 2 weeks to \< 5 months (\< 150 days) of age at the time of dosing.

Exclusion Criteria:

1. Any suspected or confirmed active viral infection at screening baseline (including HIV, Hepatitis B or C, or human T Cell lymphotropic viruses \[HTLV\])
2. History of invasive ventilatory support (tracheotomy with positive pressure) or pulse oximetry \<95% saturation.
3. Ongoing immunosuppressive therapy or immunosuppressive therapy within 3 months of starting the trial (e.g. corticosteroids, cyclosporine, tacrolimus, methotrexate, cyclophosphamide, intravenous immunoglobulin, rituximab)
4. Participation in a recent SMA treatment clinical trial that, in the opinion of the Investigator, creates unnecessary risks for gene transfer.
5. Prior history of gene therapy for any indication, hematopoietic transplant or solid organ transplant
6. Subjects with severe scoliosis
7. Known allergy or hypersensitivity to prednisolone or other glucocorticosteroids or their excipients.