Issues of safety with gene therapy August 12, 2022 - "Liver toxicity is one of the most common side effects of gene therapies like Zolgensma, which rely on adeno-associated viruses (AAVs) as vectors to deliver therapeutic genes. AAVs are mostly directed at the liver and are currently the most commonly used platform for gene therapies."
"The FDA last September held an advisory committee meeting to specifically discuss safety risks of gene therapies. During the conference, the FDA noted that about one-third of the 500 patients who had received Zolgensma at that time had experienced a liver-related side effect. Besides liver toxicity, AAV-based gene therapies have also raised concerns that they might cause cancer. Preclinical studies have shown that AAVs can incorporate genomes into certain animals, but the problem hasn’t been proven in humans."
"Meanwhile, Zolgensma has also recorded some blood system problems, including irregular platelet counts. An animal study of an experimental spinal-injection formula of Zolgensma previously also reported a neuroinflammation problem."
Yet Zolgensma has been approved by the regulatory agencies.
"Since an initial FDA nod in 2019, Zolgensma has been cleared in over 40 countries and has become a blockbuster therapy. It reeled in $379 million in sales in the second quarter, a 26% increase year-over-year."
https://www.fiercepharma.com/pharma/two-deaths-after-novartis-zolgensma-bring-gene-therapys-liver-safety-spotlight-again