Precigen Inc. has secured orphan drug exclusivity from the FDA for PAPZIMEOS, its treatment for recurrent respiratory papillomatosis (RRP), providing market protection through August 2032. This designation prevents the FDA from approving similar drugs for RRP for seven years, strengthening the product's commercial position. The company also reported encouraging long-term durability data from its pivotal study, showing sustained responses in patients without the need for additional surgeries.

Orphan drug exclusivity is granted for treatments targeting rare diseases affecting fewer than 200,000 people in the United States. Helen Sabzevari, PhD, President and CEO of Precigen, stated that this exclusivity, combined with the company's patent portfolio, enhances the product's value by strengthening market protection and long-term revenue potential.

Long-Term Clinical Data

Precigen released data from its pivotal study at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago. The study followed complete responders for a minimum of 36 months to assess the durability of the treatment.

Participants did not receive any additional treatments for RRP, including surgery or off-label investigational treatments, during the follow-up period. Dr. Sabzevari noted that these results reinforce PAPZIMEOS as a new standard of care for a disease historically managed through repeated surgeries.

Mechanism of Action and Availability

PAPZIMEOS utilizes a modified adenovirus to train the immune system to identify and attack proteins associated with HPV 6 and HPV 11, the primary causes of RRP. The treatment aims to reduce the frequency of surgeries required to remove benign tumors in the respiratory tract. Developed using Precigen's proprietary AdenoVerse therapeutic platform, the drug is currently commercially available in the U.S. and is being prescribed nationwide across major medical centers and community practices.