What's Happening?
The U.S. Food and Drug Administration (FDA) has rejected Pharming's application to expand the use of its drug Joenja (leniolisib) for treating younger patients with activated phosphoinositide 3-kinase
delta syndrome (APDS), a rare immunodeficiency disorder. The FDA issued a complete response letter (CRL) citing concerns about potential underexposure in lower-weight pediatric patients and issues with the analytical methods used for production batch testing. Joenja, which was approved in 2023 for patients aged 12 and over, is designed to inhibit the hyperactivity of PIK3 delta caused by mutations in the PIK3CD or PIK3R1 genes. Pharming plans to address the FDA's concerns and work towards resubmission.
Why It's Important?
The FDA's decision is a setback for Pharming, as Joenja is a significant revenue driver for the company, contributing €38 million ($45 million) to its sales in the first nine months of 2025. Expanding the drug's use to younger patients is crucial for Pharming's growth strategy. The rejection highlights the challenges biopharmaceutical companies face in meeting regulatory standards, particularly for treatments targeting rare diseases. The decision also underscores the importance of rigorous pharmacokinetic studies and reliable production testing methods in drug approval processes.
What's Next?
Pharming intends to collaborate closely with the FDA to address the issues raised in the CRL and determine the next steps for resubmission. The company is also pursuing approvals for Joenja in other markets, including Europe, Japan, and Canada. The outcome of these efforts will be critical for Pharming's future growth and its ability to provide treatment options for younger APDS patients, who currently lack FDA-approved therapies.
