The FDA issued draft guidance in CBER explaining how sponsors can leverage prior knowledge across gene therapy development, rather than restarting evidence generation from scratch for each program. The guidance covers ways to use platform and publicly available information to inform clinical, nonclinical, and manufacturing work. The agency said the goal is to help sponsors improve efficiency and reduce redundant studies while maintaining safety and regulatory rigor. For developers, the document effectively raises the importance of documentation around what prior knowledge is applicable to a new construct, patient population, and manufacturing process. The guidance arrives as gene therapy pipelines expand, with sponsors increasingly seeking regulatory pathways that support iterative learning across similar modalities.