Updated clinical data demonstrates that Papzimeos for adults with Recurrent Respiratory Papillomatosis (RRP) can maintain complete responses for more than four years.
RT’s Three Key Takeaways:
- Sustained Durability: Long-term follow-up data showed that 83% of complete responders maintained their status for at least 36 months, with some patients remaining surgery-free for more than four years.
- First Approved Therapy: Papzimeos is the only treatment approved by the FDA to address the underlying viral cause of recurrent respiratory papillomatosis in adults.
- Reduced Surgical Burden: The immunotherapy offers a therapeutic alternative for a chronic disease that has historically required repeated, lifelong surgical interventions to manage airway obstructions.
Precigen Inc announced updated long-term follow-up data for Papzimeos (zopapogene imadenovec-drba), demonstrating that the immunotherapy provides sustained complete responses in adults with recurrent respiratory papillomatosis (RRP). The results, presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting, include patients who have remained surgery-free for more than four years, according to the company.
Papzimeos is the first and only therapy approved by the FDA to treat the root cause of RRP. Following its full approval, the drug was granted seven-year market exclusivity.
“The presentation at ASCO marks an important maturation of the Papzimeos pivotal study data, with all complete responders now followed for at least 36 months, 83% with ongoing response, including 5 patients who are surgery-free beyond 4 years,” said Helen Sabzevari, PhD, president and CEO of Precigen. “For adults living with RRP, durability matters. These results continue to show that Papzimeos provides sustained complete responses, reinforcing its role as the new standard of care for a disease historically managed through repeated surgeries.”
RRP is a rare and potentially life-threatening respiratory condition caused by chronic infection with HPV types 6 or 11. The disease can lead to severe voice disturbances, compromised airways, and recurrent pneumonia. While the disease is rare, it carries the potential for malignant progression. Historically, patients have managed the condition through repeated surgeries to remove papillomas, which carries a risk of permanent laryngeal injury and high healthcare utilization. Internal analysis suggests there are approximately 27,000 adult RRP patients in the US.
The therapy is a non-replicating adenoviral vector-based immunotherapy designed to express a fusion antigen from HPV types 6 and 11. Administered via subcutaneous injection, the treatment is designed to trigger an immune response against the specific HPV proteins responsible for the disease.
Safety data indicated that common side effects include injection site reactions such as redness, pain, and swelling, as well as fatigue, headache, and myalgia. Healthcare providers are advised to monitor patients for at least 30 minutes after the first dose to check for potential allergic reactions or thrombotic events.
