Capsida Biotherapeutics announced on Tuesday that its investigation into the death of a child in a gene therapy trial last September has yielded no answers. The company stated that its scientific team has been unable to progress because the hospital conducting the study has refused to share tissue samples from the autopsy.

The experimental therapy, known as CAP-002, was among the first in a series of new gene therapies designed to deliver therapeutic genes deep into the brain. Researchers worldwide engineered viruses capable of crossing the blood-brain barrier, which protects the brain from harmful substances circulating in the bloodstream. These advancements sparked hope for treatments targeting devastating rare genetic diseases as well as more common conditions such as Alzheimer’s and Parkinson’s.

Source: STAT News