FDA Unveils New Regulatory Pathway to Streamline Bespoke Gene Therapies and Personalized Medicine

WASHINGTON D.C. — November 13, 2025 — Top officials at the U.S. Food and Drug Administration (FDA) today introduced a major new regulatory approach designed to accelerate the development and approval of personalized, bespoke medicines. The initiative, outlined in a paper published in The New England Journal of Medicine (NEJM) by FDA Commissioner Marty Makary and CBER Director Vinay Prasad, establishes a “plausible mechanism pathway” that allows drugmakers to reuse technology and prior safety data to streamline future regulatory reviews.

This new framework is largely inspired by the celebrated case of Baby KJ, who was treated with a custom gene editing therapy earlier this year.

The “Plausible Mechanism Pathway”

The new pathway addresses the significant regulatory challenge posed by bespoke therapies, such as those utilizing CRISPR technology, which are tailored to an individual’s specific genetic mutation. Under previous rules, each new therapy required a lengthy, stand-alone regulatory submission, even if it was scientifically almost identical to an existing medicine.

The FDA paper outlines flexibility for manufacturers who have demonstrated rigor across “several consecutive patients with different bespoke therapies.” These manufacturers can leverage “platform data”—scientific and safety information already gathered—to support the approval of similar treatments for related conditions.

Michael Lehmicke, senior vice president of scientific affairs at the Alliance for Regenerative Medicine, framed the repeatable path as essential for global competitiveness: “If you’re basically treating each one of these as truly a bespoke therapy and repeating all the same steps over and over again, it’s just not a viable approach.”

Opening Doors to Reimbursement

Crucially, the new pathway makes proven drugmakers eligible for product marketing authorization, a designation historically off-limits for bespoke medicines. Such an approval could pave the way for government and insurance payers to reimburse the often high costs of these therapies, a potential boon for biotechs and academics struggling to fund treatments for ultra-rare conditions.

The pathway is primarily envisioned for rare diseases with a clear genetic cause and a well-understood natural course, where the treatment directly targets that defect. However, the FDA notes it could also extend to more common conditions that lack effective treatments, and potentially to other drug modalities over time.

Patient Protection and Implementation

The FDA acknowledged the need for change, stating the current regulations are “onerous and unnecessarily demanding, provide unclear patient protection, and stifle innovation.”

However, the agency stressed that post-approval, companies will be required to gather real-world evidence, tracking long-term safety, off-target gene edits, and developmental outcomes.

Sharon Terry, the CEO of the advocacy group Genetic Alliance, welcomed the flexibility but cautioned against relying too heavily on post-marketing data, which she noted is “often messy, incomplete and hard to interpret.”

The publication in NEJM is light on implementation details, but it is expected to be followed shortly by official agency policy and guidance, enabling the clinical adoption of this transformative framework.