The FDA plans to hire at least 50 new clinical reviewers tasked with assessing cell and gene therapies to prepare for what the agency describes as a surge of cutting-edge products currently entering early development.
From the end of next year going forward, the agency expects to receive at least 200 investigational new drug (IND) applications annually from companies looking to begin clinical testing. The FDA predicts those will translate into 10 to 20 cell and gene therapy approvals each year by 2025.
Those 200 annual IND applications will build upon the more than 800 active cell-based or directly administered gene therapies that the agency currently has on file, according to a statement from FDA Commissioner Scott Gottlieb, M.D., and CBER Director Peter Marks, M.D., Ph.D.
“The activity reflects a turning point in the development of these technologies and their application to human health,” they wrote. “It’s similar to the period marking an acceleration in the development of antibody drugs in the late 1990s, and the mainstreaming of monoclonal antibodies as the backbone of modern treatment regimens.”
Gottlieb and Marks drew parallels between the innovative platforms that allowed engineered antibodies to be humanized, unlocking their potential by allowing them to slip past the body’s immune system, with the adoption of adeno-associated virus vectors for the delivery of gene therapies.
The agency also plans to introduce new guidance this year on its regenerative medicine advanced therapy designation, accelerated approvals and different areas of product development.
Accelerated approvals in particular could offer unique opportunities, Gottlieb and Marks wrote, citing the pathway’s additional requirements for postmarket trials. With many risks associated with long-term outcomes and rare off-target effects, premarket trials may not be feasible, while follow-up studies can help develop larger data sets, they said. The agency also plans to illustrate how the pathway can be used when targeting monogenic disorders that have no other therapies.
The FDA is also planning specific guidance on development for inherited blood disorders such as hemophilia, among others, and on allowing individual researchers to pool clinical data after following a common manufacturing protocol.
In addition, it plans to offer recommendations for developing therapies for certain neurodegenerative diseases and will urge drugmakers to take more traditional development approaches if a therapy creates genetic alterations to treat the symptoms of such disorders, by altering protein or enzyme expression, for example, instead of treating the underlying cause.
For CAR-T therapies, the agency plans to recommend how new manufacturing techniques and minor changes can be introduced without performing new clinical investigations and bridging studies, instead possibly by supplying additional real-world data.
However, with the FDA currently mired in the partial U.S. government shutdown, it’s unclear when exactly it will be able to begin moving toward these goals, instead of focusing resources on more critical duties.
“At this time, for products covered by a user fee program, including cell and gene therapy products, our review of existing medical product applications and associated policy development is funded by limited carryover user fee balances,” Gottlieb and Marks said. “We’ll continue to update the public on how we’re approaching our work.”