Rocket Pharmaceuticals Withdraws FDA Application for Fanconi Anemia Gene Therapy
In a significant development for the gene therapy landscape, Rocket Pharmaceuticals has voluntarily withdrawn its Biologics License Application (BLA) for mozafancogene autotemcel, a potential treatment for the rare blood disorder Fanconi anemia. This decision, announced in an SEC filing on October 6, 2025, marks a strategic shift for the New Jersey-based biotech company as it realigns its pipeline priorities.
Strategic Realignment and Program Prioritization
Rocket Pharmaceuticals' withdrawal of the BLA for mozafancogene autotemcel, also known as fanca-cel or RP-L102, comes on the heels of a broader corporate restructuring initiative announced in July 2025. The company emphasized that the decision was driven by "business and strategic considerations" rather than concerns about the therapy's safety or efficacy profile.
As part of its strategic realignment, Rocket has narrowed its focus to programs with clearer regulatory and commercial pathways. This restructuring resulted in a 30% reduction in workforce, with approximately 80 employees laid off. The company is now concentrating its efforts on cardiovascular gene therapies, including its Danon disease program and treatments for two forms of cardiomyopathy.
Regulatory Challenges and Future Prospects
The withdrawal of fanca-cel's BLA is not an isolated incident in Rocket's regulatory journey. In 2024, the company faced a setback when the FDA rejected its gene therapy Kresladi for severe leukocyte adhesion deficiency-I, citing manufacturing concerns. Rocket is currently working with FDA officials to address these issues and expects to resubmit the Kresladi BLA by the end of 2025.
Despite the withdrawal, Rocket maintains that data to date continue to support a favorable risk-benefit profile for fanca-cel, with no significant safety concerns documented. The company has left the door open for future development, stating it will consider external partnership opportunities to advance the program and retains the ability to re-engage with regulators if a sustainable pathway emerges.
Impact on Rare Disease Treatment Landscape
Fanca-cel is an investigational gene therapy that uses patients' own hematopoietic stem cells, modified to contain a functional copy of the FANCA gene. Its development was aimed at addressing Fanconi anemia, a rare genetic disorder characterized by bone marrow failure, congenital defects, and an increased risk of cancer.
The withdrawal of this application represents a setback for patients with this rare condition, as innovative treatments for such disorders are often limited. However, Rocket's decision to focus on programs with clearer paths to approval may ultimately lead to more successful outcomes in other areas of its pipeline.
References
- Rocket Aborts FDA Filing for Rare Blood Disease Gene Therapy
Rocket Pharmaceuticals' strategic realignment initiative in July pulled funding from fanca-cel, which the biotech was developing for Fanconi anemia.
- Rocket aborts mission to get gene therapy approved by FDA for rare bone marrow disorder
Having already altered the journey of its rare disease gene therapy to a hoped-for FDA approval, Rocket Pharmaceuticals has now aborted the mission entirely.
Explore Further
What were the clinical trial results that supported the favorable risk-benefit profile of fanca-cel?
What is the competitive landscape for Fanconi anemia treatments, and are there other gene therapies in development for this condition?
What are the regulatory and manufacturing challenges Rocket Pharmaceuticals has faced with its other gene therapy Kresladi, and how might these impact future submissions?
What is the estimated target patient population size for fanca-cel, and how does this influence the therapy's commercial viability?
What advantages does Rocket Pharmaceuticals foresee in focusing on cardiovascular gene therapies, such as those for Danon disease, compared to rare blood disorders like Fanconi anemia?