FDA Monitoring Data Accuracy Issues with Gene Therapy Product

Officials with the FDA issued a statement to clarify data accuracy issues with recently-approved gene therapy Zolgensma (onasemnogene abeparvovec-xioi, AveXis), a product intended to treat spinal muscular atrophy (SMA) in children under 2 years old.

According to the statement, AveXis had previously informed the agency about data manipulation issues that impact the accuracy of certain data from product testing performed in animals, which were submitted in the biologics license application (BLA). Although the company became aware of this issue prior to FDA approval, it did not inform the agency until after the product was reviewed.

Zolgensma was approved in May 2019 as the first gene therapy for SMA, a rare disease that is the leading genetic cause of infant mortality. The drug is indicated for pediatric patients under 2 years old with bi-allelic mutations in the survival motor neuron 1 (SMN1) gene. Through a 1-time infusion, Zolgensma delivers a copy of the gene that encodes the human SMN protein, functioning to target the cause of the disease. With its entrance into the market, Zolgensma became the most expensive drug in the world, priced at more than $2 million per patient.

Per the statement, Peter Marks, MD, PhD, director of the Center for Biologics Evaluation and Research, said that the agency is assessing the situation, but noted that there are no major concerns about the product remaining on the market. The data accuracy issues are limited to a small portion of the product testing data that was contained in the marketing application, he said. As such, the FDA does not change its positive assessment of the information from the human clinical trials that were conducted as part of the development program.

“The totality of evidence demonstrating the product’s effectiveness and its safety profile continues to provide compelling evidence supporting an overall favorable benefit-risk profile,” Marks stated. However, the agency is continuing to evaluate “the integrity of product testing data used in the development of the product’s manufacturing process.”

In response to the issue, the FDA is continuing to assess the manipulation of the product testing data used in the production process and conducting a thorough assessment of the information from a recently completed inspection.

Reference

Statement on data accuracy issues with recently approved gene therapy [news release]. FDA. https://www.fda.gov/news-events/press-announcements/statement-data-accuracy-issues-recently-approved-gene-therapy. Accessed August 6, 2019.