Gene therapies have been one of the fastest-growing fields of drug development. These therapies hold the potential to treat cancers and other “undruggable” diseases and could hold the key to saving millions of lives. But they also have unique characteristics that make them tricky to steer through the regulatory and manufacturing processes.
Research from February 2020 showed that cell and gene therapies accounted for 12% of the preclinical pipeline and 16% of the clinical pipeline, and those numbers are widely believed to have increased in the intervening years.
Drug sponsors are making substantial investments in gene therapies, and in response have asked the U.S. FDA to consider accelerating therapy development. In response, the regulatory body has changed its departmental structure to streamline approvals.
If drug sponsors are to realize the potential of gene therapies, they must be well prepared to take on the regulatory hurdles and keep their projects on track. Here are some pointers to do just that.
Understand the Challenges of Gene Therapy
To successfully navigate the development process, it’s important to understand the challenges for gene therapies in general.
Gene therapies are often lumped together but there are some key differences. Gene therapy treats, prevents or cures diseases by adding or replacing a defective gene. Nearly all of these therapies use one of three vector types to deliver the payload adeno-associated virus vectors, adenovirus vectors or lentivirus vectors.
Drug sponsors also need to consider the target toxicity of drugs before gene therapy is ready for IND submission. If there is a high toxicity in preclinical the therapy could be targeting healthy cells as well as tumor cells.
Keep Aware of Structural Changes to Ease Regulatory Delays
Drug developers who understand the structure of the FDA can gain a deeper insight into regulatory delays and ways to mitigate them. Traditional drugs are governed by the Center for Drug Evaluation and Research (CDER) but gene therapies come under the jurisdiction of the Center for Biologics Evaluation and Research (CBER). The CBER consists of several offices, including the Office of Tissues and Advanced Therapies (OTAT), which is being renamed to the Office of Therapeutic Products (OTP). This change aims to improve the functional alignment of the agency, and to increase its review capabilities and enhance expertise on gene therapies.
Consult with Regulatory Bodies
To accelerate development timelines for gene therapies, the FDA has introduced new steps to increase communication between drug sponsors and the regulators. These include four types of pre-submission meetings, which are categorized as Type A through to Type D.
Type A: These meetings are research for stalled drug development projects. They are scheduled by the FDA within 30 days of request and the background package is required at the time of the request.
Type B: Type B meetings are also known as “milestone meetings” and occur either prior to or at the end of phase 3 of drug development.
Type C: These meetings cover anything not covered in Type A or Type B. Drug developers may request a written response instead of an in-person or video conference meeting.
Type D: This is a new type of meeting that is focused and can address very specific questions, on toxicology for example, in the absence of other information. The Type D meeting gives drug sponsors the chance to gain some regulatory feedback early on in the drug delivery process.
Drug developers who engage laboratory testing partners to assist in these meetings will find they can properly set expectations with regulators over what is practical and possible easier. A lab partner can speak to the availability of testing species and the viability of testing protocols.
A Final Word
Gene therapies are an exciting and rapidly growing field of development, but there are still hurdles to overcome, particularly in manufacturing, testing and regulation. By having a proper grasp on the barriers and communicating often and clearly with regulators, drug sponsors can mitigate delays and keep timelines on track. Talk to an expert today to discuss your drug development program.
