Precigen announced that the FDA has granted orphan drug exclusivity for PAPZIMEOS (zopapogene imadenovec-drba) for the treatment of adults with recurrent respiratory papillomatosis (RRP). PAPZIMEOS received full FDA approval in August 2025 as the first and only approved therapy for adults with RRP, a rare, chronic and debilitating disease of the respiratory tract. The product is commercially available in the United States and is being prescribed at major medical centers and community practices for patients across a range of disease severities.
Orphan drug exclusivity in the US is reserved for drugs and biologics that treat rare conditions affecting fewer than 200,000 people. For PAPZIMEOS, the exclusivity period runs through August 14, 2032, providing seven years of market protection from the date of approval for its use in adults with RRP. Precigen said this regulatory milestone adds to the protection already afforded by the company’s patent portfolio covering PAPZIMEOS and its therapeutic use.
“We appreciate the FDA's recognition of seven years of orphan drug exclusivity for PAPZIMEOS, which is a testament to the groundbreaking pivotal study data and the transformative potential of PAPZIMEOS in addressing the root cause of this rare disease,” said Helen Sabzevari, PhD, president and CEO of Precigen. She added that the combination of regulatory exclusivity and patents strengthens market protection and long-term revenue potential, supporting continued innovation for rare diseases.
RRP is caused by chronic infection with human papillomavirus (HPV) types 6 or 11 and affects the upper and lower respiratory tract. The disease can lead to severe voice disturbances, airway compromise and recurrent post-obstructive pneumonia, and carries a risk of malignant transformation and death despite its rarity. Treatment has historically relied on repeated surgical procedures that do not address the underlying cause and are associated with significant morbidity and health system burden; some patients undergo hundreds of surgeries over their lifetimes, with cumulative risk of irreversible iatrogenic laryngeal injury.
Beyond physical complications, RRP can affect patients’ work, social functioning, financial stability and mental health, contributing to reduced quality of life and high health care utilization. Precigen estimates, based on internal analysis of claims data and electronic health records, that there are approximately 27,000 adult RRP patients in the United States.
Subscribe to our e-Newsletters
Stay up to date with the latest news, articles, and events. Plus, get special offers
from American Pharmaceutical Review – all delivered right to your inbox!
Sign up now!