Precigen Soars on FDA Approval for Immunotherapy Candidate

Precigen's shares surged 94% in pre-market trading after the FDA approved its immunotherapy candidate Papzimeos (zopapogene imadenovec-drba) for recurrent respiratory papillomatosis (RRP). The FDA approval marks a significant milestone for the company, which has been working on developing treatments for this rare condition. The approval is expected to boost Precigen's revenue and further establish its position in the biotech industry.

Precigen's shares surged 94% in pre-market trading on July 2, 2025, following the U.S. Food and Drug Administration (FDA) approval of its immunotherapy candidate, Papzimeos (zopapogene imadenovec-drba), for the treatment of recurrent respiratory papillomatosis (RRP). The approval marks a significant milestone for the biopharmaceutical company, which has been dedicated to developing innovative precision medicines to improve the lives of patients.

The FDA approval of Papzimeos, the first and only approved therapy for RRP, is expected to boost Precigen's revenue and further establish its position in the biotech industry. The approval came after a confirmatory clinical trial was no longer required, indicating the therapy's efficacy and safety.

RRP is a rare, debilitating, and potentially life-threatening disease caused by chronic HPV 6 or HPV 11 infection, which results in recurrent benign tumors in the respiratory tract. The condition affects approximately 27,000 adult patients in the U.S. [1]

Papzimeos is a non-replicating adenoviral vector-based immunotherapy designed to generate an immune response directed against papilloma cells expressing HPV 6/11—the root cause of RRP. It is delivered via four subcutaneous injections over a 12-week interval. The pivotal study, led by investigators at the National Institutes of Health, showed that 51% of study patients achieved a complete response, requiring no surgeries in the 12 months after treatment [1].

Precigen's President and CEO, Helen Sabzevari, PhD, stated, "For over a century, patients have relied on repeated surgeries to manage RRP. Today marks a historic turning point with the FDA approval of Papzimeos, offering adult RRP patients access to the first and only approved therapy that targets the root cause of the disease" [1].

The approval is supported by data from the open-label, single-arm, pivotal study in adult patients with RRP, which successfully met its primary safety and pre-specified primary efficacy endpoints. The study demonstrated that 51% of patients achieved a complete response, with these responses remaining durable for over 12 months [1].

Precigen will host a conference call on Monday, August 18 at 8:00 AM ET to provide additional details regarding the approval, including key aspects of the label and commercialization. The company has also established a comprehensive patient support program, Papzimeos SUPPORT, to assist patients with insurance navigation, financial assistance, and ongoing access support [1].

This FDA approval represents a significant breakthrough for the RRP community, offering patients the potential to reduce or eliminate repeated surgeries. The approval of Papzimeos is expected to have a substantial impact on Precigen's financial performance and its standing in the biotech industry.

References:
[1] https://investors.precigen.com/news-releases/news-release-details/precigen-announces-full-fda-approval-papzimeos-zopapogene