Manufacturers of cell therapy (CT) and gene therapy (GT) products will have six months of additional time to comment on a July 2013 draft guidance released by the US Food and Drug Administration (FDA), regulators announced today.
In July 2013, FDA's Center for Biologics Evaluation and Research (CBER) released a draft guidance it said would help industry in designing early-stage clinical trials for CTs and GTs.
The guidance was specifically aimed at investigational new drug (IND) applications, which are used by companies to obtain exemptions from federal law and thereby commence testing in humans.
While most IND submissions have historically been for traditional drug products like chemical or biological drugs, cellular and gene therapies are increasingly being explored as treatment options for various diseases, thus requiring clinical testing.
The process for obtaining that IND is substantially different for CT and GT products than it is for chemical or biological drugs, FDA explained. "Differences in trial design are necessitated by the distinctive features of these products, and also may reflect previous clinical experience," it wrote. "Early experiences with cellular and gene therapy (CGT) products indicate that some CGT products may pose substantial risks to subjects," including multiple organ failure, death, cancer and tumors.
"These events illustrate that the nature of the risks of CGT products can be different from those typically associated with other types of pharmaceuticals," FDA noted. Those risks largely result from the product's potential to trigger immune system responses in patients, as well as the "relatively invasive procedures" needed to administer the products.
FDA's draft guidance goes on to explain other challenges in the clinical trials process that must be accounted for, such as manufacturing changes, the difficulty of applying preclinical data to humans, and general safety concerns.
Read Regulatory Focus' explanation of the guidance, Considerations for the Design of Early-Phase Clinical Trials of Cellular and Gene Therapy Products, online here.
Six Month Delay
But while regulators originally said comments would need to be returned to FDA by 22 November 2013, it now says it will extend the comment period both to receive additional comments and to "allow for public discussion" at a February 2014 meeting of the Cellular, Tissue and Gene Therapies Advisory Committee.
There, FDA said it will present the draft guidance for public review and comment, a relatively rare action for the agency to take.
Despite the delay, FDA said it does not believe that the extra six months-comments are now due 9 May 2014-will "significantly delay further FDA action on this guidance."
Draft Guidance Explanation