Zolgensma Interim SMA Data Suggest Continued Prolonged Benefits and Event-Free Survival

Olga Santiago, MD, chief medical officer, AveXis

Olga Santiago, MD

New interim data to be presented at the 2019 European Pediatric Neurology Society (EPNS) Congress relay positive outcomes for Zolgensma (onasemnogene abeparvovec-xioi) in the treatment of spinal muscular atrophy (SMA) type 1.

According to AveXis, the Novartis company developing the agent, the data from the phase 3 STR1NT trial demonstrated an age‑appropriate “major milestone gain” when patients were treated pre‑symptomatically, as well as prolonged event-free survival, defined as the combined end point of either death or permanent ventilation.

"For families who never expected their children to reach meaningful motor milestones, the results we’re presenting at EPNS demonstrate the life-changing impact Zolgensma can have on children with SMA Type 1,” Olga Santiago, MD, chief medical officer, AveXis, said in a statement. “It is critical to diagnose SMA and begin treatment as early as possible in order to stop irreversible motor neuron loss and make the achievement of major motor milestones such as crawling, sitting and walking a possibility.”

In addition, AveXis announced that it will also highlight the interim results of the long-term follow-up to its phase 1 START study in an oral presentation. As of May 31, all 10 patients in START were alive and continued to maintain developmental milestones. Two patients gained the ability to stand with assistance, in addition to previous reports of 2 patients walking independently. As well, 70% (n = 7) of patients are not currently receiving concomitant therapy with nusinersen (Spinraza, Biogen), and 60% (n = 6) do not require daily respiratory support.

As of May 31, 2019, in the open-label, phase 3 SPR1NT trial, 10 patients with 2 copies of SMN2, 12 patients with 3 copies of SMN2 and one patient with 4 copies of SMN2 have been treated.

Zolgensma. In total, 100% of those patients are alive and event-free.

Additionally, in the group with 2 copies of SMN2, 60% (n = 6) were able to sit without support for ≥30 seconds at an average age of 7.6 months, and 30% (n = 3) were able to stand with assistance at an average age of 10.1 months.

The data also show that patients with 2 copies of SMN2 (n = 8), had a mean improvement of 8.9 points in Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND) scores at 1 month, with all patients achieving or maintaining a CHOP-INTEND score of ≥50 points. In total, 7 patients achieved CHOP-INTEND scores of ≥60 points, and 5 achieved the maximum score of 64 points.

The mean age of patients in the 2-copy and 3‑copy cohorts was 6.6 months and 4.6 months, respectively. Of the 2- and 3-copy patients who had completed their 6-month swallow evaluation, all had normal swallow function and were fed exclusively by mouth.

The FDA approved Zolgensma in May 2019 for the treatment of SMA in pediatric patients <2 years of age with mutations in the SMN1 gene, as the first and only gene therapy approved for that indication, which includes patients who are presymptomatic. The approval was based on data from the phase 3 STR1VE trial as well as the phase 1 START trial.

REFERENCES

1. AveXis presents new data at EPNS continuing to show significant therapeutic benefit of Zolgensma® in prolonging event-free survival now up to 5 years of age in patients with spinal muscular atrophy (SMA) Type 1 [press release]. Basel, Switzerland; AveXis; Published September 19, 2019. novartis.com/news/media-releases/avexis-presents-new-data-epns-continuing-show-significant-therapeutic-benefit-zolgensma-prolonging-event-free-survival-now-5-years-age-patients-spinal-muscular. Accessed September 19, 2019.

2. AveXis presented robust data at AAN demonstrating efficacy of Zolgensma® in broad spectrum of spinal muscular atrophy (SMA) patients [press release]. Basel, Switzerland: AveXis; Published May 5, 2019. novartis.com/news/media-releases/avexis-presented-robust-data-aan-demonstrating-efficacy-zolgensma-broad-spectrum-spinal-muscular-atrophy-sma-patients. Accessed September 19, 2019.