Onasemnogene Abeparvovec Brand Name– ZOLGENSMA
What is Onasemnogene Abeparvovec
Onasemnogene abeparvovec is an adeno-associated virus vector gene therapy indicated for the treatment of pediatric patients younger than 2 years of age with spinal muscular atrophy (SMA) with bi-allelic mutations in the survival motor neuron 1 (SMN1) gene.
SMA is a rare and often fatal hereditary genetic disease affecting muscle strength and movement.
It causes weakness and muscle wasting because of the loss of lower motor neurons controlling movement. The age of onset, symptoms, and rate of progression vary widely between patients.
Onasemnogene abeparvovec is given as a single dose and carries a boxed warning for acute serious liver injury.
The most common adverse reactions of onasemnogene abeparvovec are elevated liver enzymes and vomiting. An ongoing clinical trial and a completed trial in 36 pediatric patients with infantile-onset SMA (between the ages of approximately 2 weeks and 8 months at study entry) assessed the percentage of patients who survived and achieved developmental motor milestones such as sitting without support.
Efficacy was also supported by assessment of ventilator use, nutritional support, and scores on the Children’s Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND), a test assessing motor skills in patients with infantile-onset SMA.
Efficacy was based on the ongoing clinical trial; the completed clinical trial determined the dose-response relationship that helped support the effectiveness of onasemnogene abeparvovec.
In a planned interim efficacy analysis including 21 patients, 19 patients (9.4 to 18.5 months of age) were alive without permanent ventilation; 13 of these patients reached 14 months of age without permanent ventilation.
Additionally, 47.6% of patients were able to sit without support for at least 30 seconds. Based on the natural history of the disease, none of the patients that met the study entry criteria would have been expected to sit without support and only approximately 25% of these patients would be expected to survive beyond 14 months.
Because thrombocytopenia, hepatic injury, and potential cardiac toxicity can occur after onasemnogene abeparvovec infusion, platelet count, liver function (by clinical examination and laboratory testing), and cardiac troponin-I concentrations are recommended at baseline and on a regular basis for at least 3 months after therapy
Indications
- spinal muscular atrophy
For the treatment of spinal muscular atrophy (SMA)
NOTE: The FDA has designated onasemnogene abeparvovec as an orphan drug for this indication.
Side Effects
- elevated hepatic enzymes
- infection
- thrombocytopenia
- vomiting
Monitoring Parameters
- LFTs
- platelet count
- prothrombin time (PT)
- serum bilirubin
Contraindications
- breast-feeding
- cardiac disease
- hepatic disease
- pregnancy
- thrombocytopenia
- vaccination
Interactions
There are no drug interactions associated with Onasemnogene Abeparvovec products.
