Precigen gains full FDA approval for PAPZIMEOS, the first therapy for recurrent respiratory papillomatosis in adults
Saturday, August 16, 2025
Precigen, Inc. has received full approval from the U.S. Food and Drug Administration (FDA) for PAPZIMEOS™ (zopapogene imadenovec-drba), a novel immunotherapy for the treatment of adults with recurrent respiratory papillomatosis (RRP). This marks the first and only FDA-approved therapy available for adults with the condition.
PAPZIMEOS is a non-replicating adenoviral vector-based therapy designed to express a fusion antigen derived from human papillomavirus (HPV) types 6 and 11, the viruses responsible for RRP. The treatment is delivered through four subcutaneous injections over a 12-week period. Unlike previous management options, which relied mainly on repeated surgeries, PAPZIMEOS directly targets the underlying viral cause of the disease.
RRP is a rare, chronic, and sometimes life-threatening disorder of the upper and lower respiratory tract. It is caused by persistent HPV infection and can lead to severe voice problems, airway obstruction, and recurring pneumonia. Surgical removal of growths has long been the standard of care but does not prevent recurrence, resulting in a high burden for both patients and healthcare systems.
The FDA decision was based on data from an open-label, single-arm pivotal study in adults with RRP. Results showed:
- 51% (18 of 35 patients) achieved a complete response, requiring no surgeries in the 12 months following treatment. These responses were durable for more than a year, with most patients maintaining response at 24 months.
- PAPZIMEOS was well tolerated, with no dose-limiting toxicities and no treatment-related adverse events above Grade 2.
- The therapy generated HPV 6/11-specific T cell responses, with stronger immune activity observed in patients who responded compared with those who did not.
Clinical data supporting the approval were presented at the 2024 American Society of Clinical Oncology (ASCO) annual meeting and published in The Lancet Respiratory Medicine.
Source: prnewswire.com
