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DNA helix
The US Food and Drug Administration (FDA) has released several draft guidance documents on gene therapy.
Three are disease-specific guidances—for hemophilia, rare diseases, and retinal disorders—and 3 are guidances on manufacturing gene therapies.
These 6 documents are intended to serve as the building blocks of a modern, comprehensive framework for advancing the field of gene therapy, according to FDA Commissioner Scott Gottlieb, MD.
He said the documents are being issued in draft form so the FDA can solicit public input on these new policies. As with all draft guidances, all comments received will be considered before the FDA finalizes the documents.
Disease-specific guidances
The Human Gene Therapy for Rare Diseases Draft Guidance and the Human Gene Therapy for Retinal Disorders Draft Guidance include considerations for product development, preclinical research, clinical trials, expedited programs, and communication with the FDA.
The Human Gene Therapy for Hemophilia Draft Guidance covers the same topics but also includes considerations for measuring factor VIII and factor IX activity.
The draft guidance for rare diseases encompasses diseases affecting fewer than 200,000 people in the US.
Manufacturing guidances
The 3 remaining draft guidances are actually updates to existing guidances that address manufacturing issues related to gene therapy.
The first updated draft guidance, Chemistry, Manufacturing, and Control (CMC) Information for Human Gene Therapy Investigational New Drug Applications (INDs), provides sponsors with recommendations on how to provide sufficient CMC information to ensure safety, identity, quality, purity, and strength/potency of investigational gene therapy products. This guidance applies to gene therapies alone and products that contain a gene therapy in combination with a drug or device.
The second draft guidance, Testing of Retroviral Vector-Based Gene Therapy Products for Replication Competent Retrovirus (RCR) during Product Manufacture and Patient Follow-up, provides recommendations regarding the proper testing for RCR during the manufacture of retroviral vector-based gene therapy products, as well as during the follow-up monitoring of patients who have received retroviral vector-based gene therapy products.
The third draft guidance, Long Term Follow-Up (LTFU) After Administration of Human Gene Therapy Products, provides recommendations regarding the design of LTFU observational studies for the collection of data on delayed adverse events after gene therapy.
Once finalized, these draft guidances will replace previous guidances issued by the FDA in April 2008 (CMC) and November 2006 (RCR and LTFU).