Voyager Therapeutics is advancing delivery modalities for gene therapies. Many gene therapies are in development, yet delivery of the therapy is still a major limitation. AAVs are a popular choice but require high doses and have off-target effects. Voyager is using its TRACER screening platform to enhance AAV capsids’ specificity and ability to target desired cells and tissues. Voyager’s AAVs also pass the blood-brain barrier, offering the potential to cure neurological diseases. Initial non-human primate data demonstrate the selectivity of TRACER-derived capsids to target the CNS and cardiac muscle. These capsids may enable single-dose treatment for a broad spectrum of diseases.