Dive Brief:

• The Food and Drug Administration on Tuesday took another step toward expanding access to treatments for rare diseases, announcing a new proposal for personalized gene therapies.
• In the latest draft guidance, regulators focused on treatments designed to correct different mutations in the same disease-causing gene. Often, the individual mutations are so rare that traditional clinical trials are impractical or even impossible.
• Under the plan, a drugmaker could win approval for a specific personalized gene therapy targeting one mutation using more of a traditional approach, then later win clearance for different mutations with laboratory data instead of a whole new clinical study. The parameters for possible later approvals would be laid out in what the FDA is calling an “individualized feature space” in the original application.

Dive Insight:

The promise of personalized gene-editing therapies burst into the national conversation in May 2025, when a group of scientists worked together to develop a medicine for a critically ill baby named KJ Muldoon in just a few months. But most people with rare diseases face the stark fact that developing individual treatments requiring clinical studies just isn’t profitable for drugmakers.

With the latest plan, the FDA is hoping to change the economic calculus, allowing what TD Cowen analyst Joseph Thome called a “plug and play” optionality. If enacted, this draft guidance could be especially relevant for products under development by gene editing specialist Prime Medicine, Thome wrote in a note to clients. Prime shares jumped 15% early Wednesday.

Beam Therapeutics CEO John Evans says the idea would help his company too. “All of this is completely supported by the science of base editing,” Evans wrote in a series of posts on the social media platform X, referring to Beam’s core drug development technology. “But it’s still exhilarating to see the FDA crafting such a forward-looking approach.” Beam’s shares rose 8%.

The idea is part of a larger effort by the FDA to encourage drugmakers to develop treatments for rare diseases. The agency is holding a meeting Wednesday afternoon on its White Oak campus to discuss its “Rare Disease Framework Initiative,” which aims to set standards for individual conditions rather than the standard one-size-fits-all approach. Agency officials also attended a rare disease summit in Washington this week.

“Senior policymakers are clearly supportive of rare disease,” RBC Capital Markets analyst Luca Issi wrote in a note to clients about the summit. Issi sees a contrast with the “darker days” when former FDA officials Marty Makary and Vinay Prasad left drugmakers frustrated and confused by a series of hard-line stances on therapies even as they unveiled proposals designed to help speed products to market.

As part of the administration’s rare disease efforts, the Centers for Medicare and Medicaid Services is also looking to broaden a program that gives Medicaid patients access to cell and gene therapies. Initially, the focus was on sickle cell disease.

A big question for developers of gene-editing medicines has been whether one-time prices would become a “roadblock,” Beam’s Evans wrote on X. “Or would payers work to ensure access for patients and capture the long-term benefits of eliminating lifelong medical expenses and chronic treatments?”

The CMS plan to expand its access program is “great news,” he said.