BsUFA commitment letter outlines changes to FDA’s biosimilar review program
The US Food and Drug Administration (FDA) has published its proposed commitment letter for the Biosimilar User Fee Act (BsUFA IV) program, outlining several notable departures from the current biosimilar review program. FDA said the changes are intended to streamline biosimilar application reviews and enhance regulatory efficiency.
Some of these changes include the consolidation of the six BsUFA III supplement categories (Category A-F) into just two categories (Category 1 or 2) that correspond to review timelines of four and six months. Additionally, a new review mechanism will allow the FDA to continue working past the goal date to resolve late-arising issues. The agreement also would eliminate the initial, annual, and reactivation fees for biosimilar product development (BPD).
A proposal to limit the number of reference product exclusions (RPE) to make each year was dropped from the final agreement. (RELATED: BsUFA IV: Industry and FDA at impasse over reference product exclusivity, Regulatory Focus 9 June 2026)
The commitment letter was issued alongside a Federal Register notice last Friday, detailing some aspects of the agreement. The notice also announced a public meeting on 26 October to discuss these changes.
The notice states that “the proposed enhancements for BsUFA IV address many of the priorities identified by public stakeholders, the regulated industry, and FDA. The proposed enhancements modify aspects of the program to match advances in science and changes in the industry, establish new processes to increase efficiency and enhance communication, advance a lifecycle approach to addressing manufacturing issues, and enhance regulatory and financial transparency.”
The current authorization of the program (BsUFA III) expires in September 2027. Without new legislation, FDA will no longer be able to collect user fees for future fiscal years to help fund the process for the review of biosimilar products.
New for BsUFA IV
Under BsUFA IV, FDA is proposing to categorize original and resubmitted supplemental biosimilar biological product applications into two categories based on the type of change the supplement addresses and whether new manufacturing, analytical, clinical, or human factors studies data is included.
FDA said it will endeavor to review and act on 90% of Category 1 supplements within four months; these supplements do not include the aforementioned types of data and pertain to adding or modifying an indication or seeking an interchangeability determination.
For Category 2 supplements, FDA said it will aim to review and act on 90% within 6 months of receipt; these supplements include new data from manufacturing, analytical, clinical pharmacology, or human factors studies and, in addition to indication or interchangeability changes, may also address the addition of new strengths, dosage forms, or routes of administration, as well as the introduction of new delivery devices or container closure systems.
A new review mechanism called “imminent action” would allow FDA to work past a goal date to address late arising and resolvable issues. According to the notice, “this should help avoid otherwise unnecessary provisional determinations and complete response actions. Imminent action will not function as a routine mechanism to extend the review cycle.”
The agreement removes the initial, annual, and reactivation of BPD fees. This elimination would remove “historical cost barriers established early in the biosimilar program to fund baseline growth.” Additionally, for sponsors planning to submit multiple biologics license applications (BLAs) that contain largely the same information about the drug substance, BsUFA IV will introduce a tiered application fee. This fee structure aims to encourage such sponsors to submit their BLAs simultaneously.
FDA is also proposing a third-party assessment of review processes and communications between FDA and sponsors during first cycle review to enhance the efficiency of the biosimilar development and regulatory review program.
The agency plans to publish a biosimilar-specific pediatric study plan (iPSP) template to enhance the efficiency of iPSP submissions and make it available for public comment. Additionally, the agency proposes to issue guidance addressing pediatric study plans for biosimilar products.
The Biosimilar Initial Advisory (BIA) meeting would be eliminated under the proposed commitment letter. Instead, BIA meetings would be replaced with Type 2b meeting as the initial interaction for sponsors to discuss their proposed development programs.
To enhance the timely development and availability of biosimilar products, FDA proposes a BsUFA IV chemistry, manufacturing, and controls (CMC) facility lifecycle program. The program introduces a new option for a single CMC facility pre-submission meeting to discuss manufacturing facilities for a proposed application to facilitate readiness before a facility evaluation and inspection.
FDA is also proposing to end the BsUFA Regulatory Science Pilot Program, as its goals have been achieved, the agency said.
Finally, the agency is proposing a personnel compensation and benefits (PC&B) set-aside to ensure the agency will reserve the necessary funding to restaff the BsUFA program at a level consistent with FY 2025, with adjustment for terminated staff. A similar set-aside was part of the PDUFA VIII commitment letter. (RELATED: PDUFA VIII: FDA outlines goals, program enhancements in commitment letter, Regulatory Focus 13 August 2026)
Both the Pharmaceutical Research and Manufacturers of America (PhRMA) and the Association for Accessible Medicines (AAM) expressed their support for the agreement.
PhRMA wrote that BsUFA IV builds on the progress established of former user fee agreements and focuses on “enhancing the FDA’s core review functions through improving review efficiency and ensuring the FDA’s resources are used effectively to support timely review of safe and effective biosimilars. The agreement also enhances opportunities for communication between the FDA and biosimilar sponsors throughout the review process and increases transparency. Together, these improvements will help ensure a predictable and effective regulatory pathway supporting continued biosimilar development and timely access for patients.”
AAM and its Biosimilar Council said the agreement “represents an opportunity to continue modernizing the biosimilar development and review process. Greater regulatory efficiency, improved sponsor-FDA communication, appropriate use of advances in analytical science, and a predictable review process can reduce unnecessary development burdens while maintaining FDA’s rigorous standards for safety, purity, and potency.”
