Precigen announces long-term RRP treatment data with PAPZIMEOS.

Precigen announced long-term follow-up data for PAPZIMEOS, a treatment for recurrent respiratory papillomatosis, at the AAO-HNSF 2025 Annual Meeting. 83% of patients (15 out of 18) demonstrated continued complete response with a median follow-up of 36 months. Reductions in surgeries were observed in 86% of patients in Year 1, 91% in Year 2, and 95% in Year 3. No new safety events were observed during long-term follow-up.

Precigen, Inc. (Nasdaq: PGEN) recently presented long-term follow-up data for PAPZIMEOS™ (zopapogene imadenovec-drba) at the American Academy of Otolaryngology–Head and Neck Surgery Foundation (AAO-HNSF) 2025 Annual Meeting. The data demonstrated the ongoing efficacy and safety of PAPZIMEOS in treating adults with recurrent respiratory papillomatosis (RRP).

The study, which included 35 patients, showed that 51% (18 out of 35) achieved complete response within 12 months of treatment, requiring no surgeries. Of these 18 complete responders, 15 (83%) maintained their complete response status as of the September 19, 2025 data cutoff, with a median follow-up duration of 36 months Precigen Announces Long-Term Follow-Up Results Highlighting Ongoing Durable Complete Responses after Treatment with PAPZIMEOS, the First and Only FDA-approved Therapy for Adults with Recurrent Respiratory Papillomatosis^[1].

Reductions in surgeries were observed in 86% of patients in Year 1, 91% in Year 2, and 95% in Year 3. This indicates a sustained reduction in the need for surgical interventions to manage RRP over the long term. Notably, no new safety events were observed during the extended follow-up period, underscoring the safety profile of PAPZIMEOS Precigen Announces Long-Term Follow-Up Results Highlighting Ongoing Durable Complete Responses after Treatment with PAPZIMEOS, the First and Only FDA-approved Therapy for Adults with Recurrent Respiratory Papillomatosis^[1].

Helen Sabzevari, PhD, President and CEO of Precigen, commented, "The updated durability data reinforce that PAPZIMEOS is not only a medical breakthrough but a transformative therapy for the RRP community. For patients and their families, sustained responses mean freedom from the relentless cycle of repeat surgeries, reduction in the risk of surgical damage, and the possibility to improve quality of life. For physicians, it provides confidence in a safe and effective therapy that addresses the root cause of disease. And for the healthcare system, durable responses translate into fewer procedures, reduced complications, and lower long-term burden of care. This is precisely the type of impact we envisioned when we set out to develop what would become the first FDA-approved therapy for adults with RRP."

RRP is a rare, debilitating disease of the upper and lower respiratory tract caused by chronic HPV 6 or HPV 11 infection. Management of RRP has primarily consisted of repeated surgeries, which do not address the underlying cause of the disease and can be associated with significant morbidity as well as significant patient and health system burden.

PAPZIMEOS is the first and only FDA-approved therapy for the treatment of adults with RRP and the first and only approved therapy to address the root cause of RRP. It is a non-replicating adenoviral vector-based immunotherapy designed to generate an immune response directed against HPV 6 and HPV 11 proteins.

The long-term follow-up data further support the clinical efficacy and safety of PAPZIMEOS, positioning it as a significant advancement in the treatment of RRP. As the FDA-approved therapy, PAPZIMEOS offers patients and healthcare providers a novel approach to managing this challenging disease.