Researchers, clinicians, and families must weigh the life-saving potential of AAV-based treatments against the newly confirmed cancer risk.

This represents a significant turn in the field and underscores the need to design improved therapies that mitigate cancer risk in AAV-based approaches.

AAVs, used to deliver therapeutic genes, have been implicated in cancer development in new cases this year.

The emerging evidence settles a long-standing debate about whether AAVs can drive tumors, shifting risk-benefit considerations for gene therapies.

Clinicians like Sam Mackenzie of the University of Rochester say the risk will alter decision-making for patients, especially those with spinal muscular atrophy.