FDA Denies Approval for Regeneron's Lymphoma Treatment

Regeneron Pharmaceuticals has encountered a setback in its bid to gain FDA approval for its bispecific antibody drug, odronextamab, used in the treatment of relapsed/refractory follicular lymphoma and diffuse large B-cell lymphoma. The FDA issued Complete Response Letters (CRLs) to the company, citing concerns related to the enrollment status of confirmatory trials as the sole approvability issue. The CRLs did not indicate any issues with the drug's efficacy, safety, trial design, labeling, or manufacturing processes.

The FDA has mandated that the ongoing Phase III trials for odronextamab must include both dose-finding and confirmatory stages, with enrollment in the latter being a prerequisite for resubmission. Regeneron has been actively enrolling patients for these trials and is committed to collaborating with the FDA and investigators to expedite the drug's availability to patients. The company intends to provide updates on enrollment and regulatory timelines later in the year.

Odronextamab was granted priority review by the FDA and has demonstrated promising results in clinical trials. In a Phase II trial involving 128 patients, 80% achieved an objective response, with 73% experiencing a complete response. The median duration of response was 23 months, and the median time for a full response was 24 months, with an average progression-free survival time of 28 months.

In August 2023, the European Medicines Agency initiated a regulatory review of odronextamab, which is still in progress. The drug has also received orphan drug designation from the European Union.

Regeneron is not alone in facing regulatory challenges; recently, the FDA rejected a formulation of glatiramer acetate by Viatris and Mapi Pharma for treating multiple sclerosis, though the reasons for the rejection were not disclosed.

On a positive note, the FDA accepted a supplemental Biologics License Application from Regeneron and Sanofi to expand the use of Dupixent to include chronic obstructive pulmonary disease.

The regulatory environment for pharmaceuticals is complex, with companies navigating a path to approval that involves rigorous trials and compliance with regulatory standards. The journey of odronextamab highlights the importance of thorough clinical trials and the need for clear communication and collaboration between pharmaceutical companies and regulatory bodies to ensure the safety and efficacy of new treatments.