Fast Track, Breakthrough Therapy and RMAT: Choosing the Right FDA Expedited Pathway

In an increasingly competitive and time-sensitive drug development environment, the ability to accelerate regulatory timelines can be a critical differentiator. The U.S. Food and Drug Administration (FDA) has established several expedited programs to facilitate the development and review of therapies that address serious conditions and unmet medical needs.

Three FDA expedited development programs warrant particular attention: Fast Track, Breakthrough Therapy, and Regenerative Medicine Advanced Therapy (RMAT), each distinct in its eligibility criteria and strategic application. Think of these pathways as tools to optimize regulatory strategy: when used effectively, they can shape development plans, enhance sponsor–agency engagement, and ultimately improve the likelihood of timely approval.

What are Fast Track, Breakthrough Therapy, and RMAT, and How Do They Differ?

All three designations require sponsors to demonstrate that their product is intended to treat a serious condition and address an unmet medical need. FDA defines unmet medical need as a condition whose treatment or diagnosis is not addressed adequately by available therapy, and serious disease or condition is a disease or condition associated with morbidity that has substantial impact on day-to-day functioning.  

Sponsors may apply for one or more of these designations for the same drug or biologic, if the eligibility criteria are met. While all three programs are intended to accelerate development, they differ in eligibility criteria, evidentiary requirements, and the level of FDA engagement provided.

• Fast Track is intended for therapies that treat serious conditions and have the potential to address unmet medical needs. Fast Track designation is often the earliest entry point into expedited development as it can be granted based on nonclinical or early clinical data. Sponsors benefit from more frequent interactions with the FDA and the option for rolling review, which allows portions of a new drug application (NDA) or biologics license application (BLA) to be submitted separately and, in some cases, reviewed on an ongoing basis.
• Breakthrough Therapy designation represents a step up from Fast Track in both expectations and benefits. It requires preliminary clinical evidence indicating that the therapy may offer substantial improvement over existing treatments on clinically meaningful endpoints. In return, sponsors receive intensive FDA guidance, often involving senior agency staff, to support efficient development. This level of engagement can significantly influence trial design and overall development strategy. Rolling review of the NDA or BLA is also an option.
• Regenerative Medicine Advanced Therapy (RMAT) designation is specific to regenerative medicine products, including cell and gene therapies, therapeutic tissue engineering products, and certain combination products. Like Breakthrough Therapy designation, RMAT requires preliminary clinical evidence demonstrating the potential to address an unmet need for a serious condition and provides sponsors with many of the same expedited development benefits. However, considering the unique challenges associated with these products, RMAT also offers unique flexibility in demonstrating effectiveness, such as the potential use of surrogate or intermediate endpoints and tailored post-approval evidence generation strategies.

In practice, the distinctions between these pathways come down to timing, data maturity, and product type. Fast Track enables earlier access to expedited features with a lower evidentiary bar, while Breakthrough Therapy and RMAT designations require more robust clinical data but provide greater regulatory engagement and, in the case of RMAT, added flexibility for regenerative therapies.

Timing and Submission Considerations

For Fast Track designation, requests are commonly submitted early in development because eligibility may be supported by nonclinical findings or preliminary clinical data demonstrating the potential to address an unmet medical need. In contrast, Breakthrough Therapy and RMAT designations require preliminary clinical evidence suggesting the therapy may provide substantial improvement over available therapies or meaningfully address unmet needs in serious conditions. As a result, these requests are typically submitted after initial clinical proof-of-concept has been established.

Although sponsors may pursue multiple expedited designations for the same product, each request should be submitted separately and tailored to the specific statutory and evidentiary requirements of the program. A strong designation request not only summarizes the available data, but also clearly articulates the clinical context, unmet need, and rationale for why the product qualifies for the expedited development support.

FDA generally responds to designation requests within 60 calendar days of receipt. If granted, the designation remains in effect throughout development unless emerging data no longer supports the qualifying criteria, at which point FDA may rescind it. Once designation is granted, sponsors are expected to keep FDA informed of meaningful development updates, including changes in clinical data or program direction that may affect the basis for designation. In the case of Breakthrough Therapy and RMAT, FDA typically directs sponsors to request a Type B meeting following designation – an early opportunity to align on trial design, endpoints, and overall development strategy.

How Boyds Can Help

While the pathways themselves are well-defined, effectively leveraging them requires strategic timing, careful data positioning, and a clear understanding of FDA expectations.

We work with sponsors to identify the most advantageous designation opportunities based on their specific program, ensuring that applications are submitted at the right time and supported by the strongest possible evidence. From early-stage gap assessments to the preparation of designation requests, our team focuses on building clear, persuasive narratives that resonate with FDA reviewers.

Beyond the initial designation, we help clients fully leverage the benefits of these programs by guiding FDA interactions, supporting meeting preparation, and aligning expedited pathways with broader development and commercialization strategies. The result is not just a successful designation request, but a more efficient and strategically coherent development program.