Effects of gene replacement therapy with resamirigene bilparvovec (AT132) on skeletal muscle pathology in X-linked myotubular myopathy : results from a substudy of the ASPIRO open-label clinical trial

Copyright © 2023. Published by Elsevier B.V..

BACKGROUND: X-linked myotubular myopathy (XLMTM) is a rare, life-threatening congenital muscle disease caused by mutations in the MTM1 gene that result in profound muscle weakness, significant respiratory insufficiency, and high infant mortality. There is no approved disease-modifying therapy for XLMTM. Resamirigene bilparvovec (AT132; rAAV8-Des-hMTM1) is an investigational adeno-associated virus (AAV8)-mediated gene replacement therapy designed to deliver MTM1 to skeletal muscle cells and achieve long-term correction of XLMTM-related muscle pathology. The clinical trial ASPIRO (NCT03199469) investigating resamirigene bilparvovec in XLMTM is currently paused while the risk:benefit balance associated with this gene therapy is further investigated.

METHODS: Muscle biopsies were taken before treatment and 24 and 48 weeks after treatment from ten boys with XLMTM in a clinical trial of resamirigene bilparvovec (ASPIRO; NCT03199469). Comprehensive histopathological analysis was performed.

FINDINGS: Baseline biopsies uniformly showed findings characteristic of XLMTM, including small myofibres, increased internal or central nucleation, and central aggregates of organelles. Biopsies taken at 24 weeks post-treatment showed marked improvement of organelle localisation, without apparent increases in myofibre size in most participants. Biopsies taken at 48 weeks, however, did show statistically significant increases in myofibre size in all nine biopsies evaluated at this timepoint. Histopathological endpoints that did not demonstrate statistically significant changes with treatment included the degree of internal/central nucleation, numbers of triad structures, fibre type distributions, and numbers of satellite cells. Limited (predominantly mild) treatment-associated inflammatory changes were seen in biopsy specimens from five participants.

INTERPRETATION: Muscle biopsies from individuals with XLMTM treated with resamirigene bilparvovec display statistically significant improvement in organelle localisation and myofibre size during a period of substantial improvements in muscle strength and respiratory function. This study identifies valuable histological endpoints for tracking treatment-related gains with resamirigene bilparvovec, as well as endpoints that did not show strong correlation with clinical improvement in this human study.

FUNDING: Astellas Gene Therapies (formerly Audentes Therapeutics, Inc.).

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:99

Enthalten in:

EBioMedicine - 99(2024) vom: 12. Jan., Seite 104894

Sprache:

Englisch

Beteiligte Personen:

Lawlor, Michael W [VerfasserIn]
Schoser, Benedikt [VerfasserIn]
Margeta, Marta [VerfasserIn]
Sewry, Caroline A [VerfasserIn]
Jones, Karra A [VerfasserIn]
Shieh, Perry B [VerfasserIn]
Kuntz, Nancy L [VerfasserIn]
Smith, Barbara K [VerfasserIn]
Dowling, James J [VerfasserIn]
Müller-Felber, Wolfgang [VerfasserIn]
Bönnemann, Carsten G [VerfasserIn]
Seferian, Andreea M [VerfasserIn]
Blaschek, Astrid [VerfasserIn]
Neuhaus, Sarah [VerfasserIn]
Foley, A Reghan [VerfasserIn]
Saade, Dimah N [VerfasserIn]
Tsuchiya, Etsuko [VerfasserIn]
Qasim, Ummulwara R [VerfasserIn]
Beatka, Margaret [VerfasserIn]
Prom, Mariah J [VerfasserIn]
Ott, Emily [VerfasserIn]
Danielson, Susan [VerfasserIn]
Krakau, Paul [VerfasserIn]
Kumar, Suresh N [VerfasserIn]
Meng, Hui [VerfasserIn]
Vanden Avond, Mark [VerfasserIn]
Wells, Clive [VerfasserIn]
Gordish-Dressman, Heather [VerfasserIn]
Beggs, Alan H [VerfasserIn]
Christensen, Sarah [VerfasserIn]
Conner, Edward [VerfasserIn]
James, Emma S [VerfasserIn]
Lee, Jun [VerfasserIn]
Sadhu, Chanchal [VerfasserIn]
Miller, Weston [VerfasserIn]
Sepulveda, Bryan [VerfasserIn]
Varfaj, Fatbardha [VerfasserIn]
Prasad, Suyash [VerfasserIn]
Rico, Salvador [VerfasserIn]

Links:

Volltext

Themen:

Adeno-associated viral vector
Centronuclear myopathy
Gene replacement therapy
Human
Journal Article
Pathology
X-linked myotubular myopathy

Anmerkungen:

Date Completed 22.01.2024

Date Revised 22.01.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.ebiom.2023.104894

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM365768952