AveXis presented positive results from clinical trials on Zolgensma, across a broad spectrum of patients with SMA at the 2019 American Academy of Neurology conference in Philadelphia.
Zolgensma is a gene therapy product designed to address the genetic root cause of SMA and prevent further muscle degeneration by providing a functional copy of the human SMN gene to halt disease progression through sustained SMN protein expression. Data from 3 trials were presented:
- The STRONG trial, which tested Zolgensma administered intrathecally in 30 Type II SMA patients. The data presented showed motor function gains and milestone achievements. Just two serious treatment-related adverse events occurred, both transaminase elevation. Transaminases are liver enzymes, which when elevated, indicate liver damage. However, the frequency of patients with such adverse events appeared to be lower than that seen with intravenous (IV) administration of Zolgensma;
- The phase 3 STR1VE trial evaluates the efficacy and safety of a one-time IV infusion of Zolgensma in patients with SMA Type 1, who are older than 6 months of age at the time of gene therapy. The new data presented continued to show prolonged, event-free survival, increases in motor function and significant milestone achievement;
- The phase 3 SPR1NT trial, which is testing Zolgensma administered intravenously in pre-symptomatic Type 1 patients older than 6 weeks, showed motor milestone achievement consistent with normal development. Three serious adverse events occurred but were considered unrelated to treatment. Other observed adverse events included elevated transaminases, elevated blood creatine phosphokinase MB and elevated troponin.