Precigen Inc (Nasdaq: PGEN), a US-based biopharmaceutical company specialising in the advancement of innovative precision medicines, announced on Friday that the US Food and Drug Administration (FDA) has approved PAPZIMEOS (zopapogene imadenovec-drba) for the treatment of adults with recurrent respiratory papillomatosis (RRP).

PAPZIMEOS is claimed to be the first and only FDA-approved therapy for the treatment of adults with RRP. Precigen completed submission of the rolling Biologics License Application (BLA) in December 2024 under an accelerated approval pathway; however, the FDA has granted PAPZIMEOS full approval, which does not require a confirmatory clinical trial.

The company says that PAPZIMEOS is a non-replicating adenoviral vector-based immunotherapy designed to express a fusion antigen comprising selected regions of human papillomavirus (HPV) types 6 and 11 proteins-the root cause of RRP. PAPZIMEOS is delivered via four subcutaneous injections over a 12-week interval.

RRP is a rare, debilitating, and potentially life-threatening disease of the upper and lower respiratory tract caused by chronic HPV 6 or HPV 11 infection. RRP can lead to severe voice disturbance, a compromised airway, and recurrent post-obstructive pneumonias. Management of RRP has primarily consisted of repeated surgeries, which do not address the root cause of the disease and can be associated with significant morbidity as well as significant patient and health system burden.

"For more than a century, since RRP was first recognised as a distinct disease, patients have had to rely on repeated surgeries to manage this relentless condition. Today marks a historic turning point. With the landmark FDA approval of PAPZIMEOS and broad label, all adult RRP patients are now eligible for access to the first and only approved therapy that targets the root cause of the disease," said Helen Sabzevari, PhD, Precigen president and CEO. "This milestone affirms the power of our AdenoVerse platform and the exceptional capabilities of our team to rapidly advance a wholly novel therapy from discovery to approval considerably faster than industry benchmarks. We are profoundly grateful to the NIH clinicians, the FDA, and-most importantly-the patients and families who made this breakthrough possible. We look forward to swiftly delivering PAPZIMEOS to the RRP community and ushering in a new era of treatment that targets the underlying cause of the disease rather than just managing its symptoms."

The approval is supported by positive data from the open-label, single-arm, pivotal study in adult patients with RRP. The pivotal study was led by lead investigators, Clint T. Allen, MD, and Scott M. Norberg, DO, at the National Institutes of Health. Pivotal data were presented at the 2024 American Society of Clinical Oncology (ASCO) annual meeting and published in The Lancet Respiratory Medicine.

Precigen says that it will begin promoting PAPZIMEOS immediately and is committed to helping patients with RRP access the therapy.