Precigen Receives Orphan Drug Designation for PRGN-AdenoVerse™ Immunotherapy for Respiratory Papillomatosis

Precigen announced the US Food and Drug Administration (FDA) has granted orphan drug designation (ODD) for PRGN-2012, a first-in-class, investigational off-the-shelf (OTS) AdenoVerse™ immunotherapy for recurrent respiratory papillomatosis (RRP). In January 2021, Precigen announced the clearance of the IND to Initiate a Phase I study of PRGN-2012 AdenoVerse™ immunotherapy in adult patients with RRP. PRGN-2012 is under development through a Cooperative Research and Development Agreement (CRADA) with the Center for Cancer Research (CCR) at the National Cancer Institute (NCI), which is part of the National Institutes of Health (NIH).

Orphan drug designation is granted by the FDA to drugs intended to treat rare diseases or disorders that affect fewer than 200,000 people in the US. The sponsor of a drug that receives the designation may qualify for a number of incentives that help to expedite and reduce the cost of development, approval and commercialization, such as grants, clinical design support, FDA fee waivers, tax incentives, and seven years of marketing exclusivity.

"This regulatory designation underscores the critical medical need for new therapies to treat this devastating and sometimes fatal disease," said Helen Sabzevari, PhD, President and CEO of Precigen. "As the first regulatory designation for our proprietary AdenoVerse platform, this orphan drug designation will help to advance PRGN-2012 with important incentives that support delivery of this medicine as rapidly as possible to patients suffering from RRP."

PRGN-2012 is an innovative therapeutic vaccine with optimized antigen design that uses gorilla adenovector technology, part of Precigen's proprietary AdenoVerse platform, to elicit immune responses directed against cells infected with HPV 6 or HPV 11. Gorilla adenovectors have numerous advantages, including the ability for repeat administration, the inability to replicate in vivo, which may improve safety, and the ability to deliver large payload capacity. In preclinical models, PRGN-2012 has demonstrated strong and specific immune response against HPV 6 and HPV 11.

Recurrent respiratory papillomatosis (RRP) is a rare, difficult-to-treat and sometimes fatal neoplastic disease of the upper and lower respiratory tracts that is caused by infection with HPV 6 or HPV 11. RRP is classified based on age of onset as juvenile or adult. Juvenile-onset disease has an incidence of 4 per 100,000 and adult-onset RRP has an incidence of 2 to 3 per 100,000. There is no cure for RRP and the current standard-of-care is repeated endoscopic debulking with ablation or excision of papillomatous lesions. Recurrence of papilloma after surgical removal is very common and repeated procedures are required to debulk and monitor the disease, which exposes patients to anesthetic and surgical risks, and emotional distress. RRP morbidity and mortality results from the effects of papilloma mass on the vocal cords, trachea, and lungs, which may cause voice changes, stridor, airway occlusion, loss of lung volume, and/or post-obstructive pneumonia. Although rare, one to three percent of RRP cases can transform into invasive squamous cell carcinoma.