Capsida Biotherapeutics said it still has no answers after investigating the death of a child in its gene therapy trial of CAP-002 last September. The company said progress has been stymied because the hospital where the study was conducted has declined to share tissue samples from an autopsy. CAP-002 is described as the first of a wave of gene therapies intended to deliver genes deep into the brain. The case has drawn broad attention because it involves delivery across the blood-brain barrier and the use of viral vectors in neurogenetic disease. Capsida’s statement keeps the focus on trial-site cooperation and data access as key factors in causality assessments after adverse events.