FDA Draft Guidances Target Individualized Gene Therapies

The FDA offered advice for sponsors of individualized drugs developed for use against life-threatening genetic diseases in two draft guidances released this week.

The guidances, one focused on clinical trials, the other on chemistry, manufacturing and controls (CMC), specifically target antisense oligonucleotide (ASO) products ― individualized drugs used to alter RNA to change protein mechanisms.

If more than a few patients can be considered candidates for the targeted treatment with the ASO product, then the drug is “no longer considered individualized, and the sponsor should discuss a drug development plan of the investigational ASO drug product for a larger patient population with the relevant review division,” the FDA said.

In the CMC draft guidance, the agency said the individualized ASO products should be from “a well-characterized chemical class for which there is substantial clinical and nonclinical experience,” and sponsors should thoroughly describe the drug substance.