Section 12 · Monograph
Atidarsagene autotemcel
Reviewed Nov 2026FDA label
LenmeldyAutologous stem-cell gene therapy
- Forms
- IV suspension: autologous CD34+ gene-modified cells
- Dose
- Metachromatic leukodystrophy (pre-symptomatic late infantile or early juvenile; early symptomatic early juvenile): single IV infusion after myeloablative busulfan conditioning
- MOA
- Lentiviral ARSA gene transfer into CD34+ cells
Indications
- Pre-symptomatic late infantile, pre-symptomatic early juvenile, and early symptomatic early juvenile metachromatic leukodystrophy (MLD)FDA-labeled
Mechanism of Action
- Gene-modified autologous hematopoietic stem cells give rise to progeny that express arylsulfatase A, crossing into the CNS to reduce sulfatide accumulation
Full Dosing
Adult / usual
- Single IV infusion of autologous CD34+ hematopoietic stem cells transduced with a lentiviral vector encoding ARSA, given after myeloablative busulfan conditioning
- Requires stem-cell mobilization, apheresis and manufacturing; treatment only at qualified centers
- Repeat treatment is considered investigational
Contraindications
- None listed; hypersensitivity to components and contraindications related to busulfan conditioning apply
Drug Interactions
- Avoid live vaccines around conditioning; coordinate antimicrobial prophylaxis and growth-factor use per label
Adverse Effects
- Cytopenias including neutropenia and thrombocytopenia
- Serious infections and febrile neutropenia
- Thrombosis and thromboembolic events, encephalitis
- Mucositis and busulfan-related toxicities
- Theoretical risk of insertional oncogenesis
Monitoring Parameters
- CBC with differential and platelets until engraftment and recovery
- MRI, ARSA activity and vector copy number
- Long-term follow-up for malignancy and neurologic function
Pregnancy & Lactation
- Conditioning agents cause embryo-fetal toxicity and infertility; counsel on fertility preservation and contraception