Already having changed the path of its rare disease gene therapy toward a hoped-for FDA approval, Rocket Pharmaceuticals has now cancelled the mission altogether.
In the first quarter of the year, the biotech submitted a rolling biologics license application (BLA) covering the candidate, which is sometimes referred to as RP-L102, mozafancogene autotemcel, or Fanca-cel. It was used specifically to treat the rare genetic disorder of bone marrow failure known as Fanconi anemia.
The future of the application was already uncertain in July, when Rocket announced it was looking to hold up the RP-L102 program as part of a broader reorganization of the company pipeline and workforce. The biotech also withdrew its approval application to European regulators at the time and said it no longer planned to obtain an FDA approval by 2026.
The company said it has voluntarily withdrawn the BLA, citing the decision as a result of July’s reprioritization, under which Rocket is channeling its resources towards programs that have the most regulatory and commercial avenues.
The choice was not based on any safety or efficacy issues but was made as a result of business and strategic factors, the company emphasized in an Oct. 3 filing to the Securities and Exchange Commission.
The biotech added that the company will look at external partnership opportunities that may potentially facilitate the development of RP-L102 in the future. By not withdrawing the BLA, Rocket retains the right to re-engage with regulators in the future in the event of an appropriate strategic direction or partnership route to continue program development in a sustainable way.
Rocket has had a bumpy few years with regulators. Last year, on production grounds, the FDA refused the application of Rocket to have Kresladi approved as a drug to treat severe leukocyte adhesion deficiency-I. The company has now projected to re-file that BLA by the year ending 2025.
A key trial of the AAV9 gene therapy RP-A50 in Danon disease was placed on clinical hold in May of this year, around the time of a death in the trial, and was only approved to resume last month.
Rocket is being restructured to no longer depend on its hematology businesses, although Kresladi stands as a priority, but to concentrate on the cardiovascular side of the pipeline, the Danon program, and the treatment of two types of cardiomyopathy.
As part of its refocusing, Rocket is transitioning away from hematology as a core area and placing greater emphasis on its cardiovascular pipeline, including Danon disease and cardiomyopathy programs. The cancellation of the RP-L102 FDA application frees up capital and organizational bandwidth to advance these prioritized assets.
In the coming months, all eyes will be on how Rocket navigates partnerships for RP-L102’s potential revival, and how swiftly it can recover momentum in the face of regulatory and clinical headwinds. Rocket’s ability to leverage FDA relationships, manage safety oversight in complex gene therapy trials, and efficiently allocate limited resources could define its trajectory in the increasingly competitive rare disease space.
The decision by Rocket Pharmaceuticals to withdraw its FDA application marks a broader trend among biotech firms reassessing their strategic priorities in a tightening market. Over the past two years, many gene therapy developers have faced similar challenges—ranging from high production costs to regulatory hurdles—that have slowed the pace of innovation. The FDA’s evolving stance on gene therapy safety and long-term efficacy data has also made approvals more complex, demanding extensive evidence of sustained benefit and risk management.
For Rocket, the withdrawal provides an opportunity to streamline operations and refocus its scientific capabilities on programs that align with market needs and FDA expectations. Analysts suggest that while the move may appear like a setback, it could allow the company to consolidate its financial resources and build stronger clinical evidence for future submissions.
