A clinical trial led by researchers at the National Institutes of Health (NIH) has demonstrated that an experimental gene therapy called PRGN-2012 may be an effective treatment for patients with recurrent respiratory papillomatosis (RRP). This rare, debilitating condition, caused by chronic infection with human papillomavirus (HPV) types 6 and 11, produces noncancerous tumors, or papillomas, throughout the respiratory tract that affect a person’s voice and breathing. The results were published on January 21, 2025, in The Lancet Respiratory Medicine.

Doctors currently use surgery to manage RRP, but repeated surgeries can eventually damage a person’s vocal cords and airways. PRGN-2012 uses a modified gorilla adenovirus, designed by the biopharma company Precigen, to deliver genes that elicit immune responses directed against cells infected with HPV 6 or HPV 11. In the phase 1/2 trial, 35 adults with RRP were treated with PRGN-2012 following papilloma-removal surgery. Of these patients, 18 did not need any procedures to remove papillomas in the year after treatment. After a median follow-up of 22 months, 15 patients still did not need further procedures. Side effects, which included fatigue and chills, were mild.

The trial was conducted as part of a Cooperative Research and Development Agreement between NIH’s National Cancer Institute and Precigen.   back...