A NOVEL therapeutic vaccine, PRGN-2012, has shown promising results in treating recurrent respiratory papillomatosis, a rare and debilitating condition caused by chronic infection with human papillomavirus type 6 or 11, according to findings from a Phase 1/2 clinical trial.
This single-centre, single-arm trial enrolled adult patients aged 18 years or older who had required at least three surgical interventions for recurrent respiratory papillomatosis in the previous year. Following surgical debulking, participants received four doses of PRGN-2012 over a 12-week period. The primary outcome was complete response rate, defined as the absence of a need for further surgical intervention within 12 months after treatment. Safety was also assessed, with adverse events recorded throughout the study.
Between March 2021 and June 2023, 38 patients were enrolled, with 35 receiving the recommended Phase 2 dose of 5×10¹¹ particle units. Of these, 51% (18 out of 35, 95% CI: 34–69) achieved a complete response, with the median duration of response yet to be determined. Treatment-related adverse events were generally mild, with the most common being injection site reactions (97%), fatigue (80%), chills (71%), and fever (69%), all graded at severity levels 1 or 2.
These results suggest that PRGN-2012 is a safe and effective potential treatment for recurrent respiratory papillomatosis. Based on these findings, a biologics license application is planned with the US Food and Drug Administration, paving the way for its potential approval as the first systemic therapy for this condition.
Reference
Norberg SM et al. PRGN-2012 gene therapy in adults with recurrent respiratory papillomatosis: a pivotal phase 1/2 clinical trial. Lancet Respir Med. 2025; DOI: 10.1016/S2213-2600(24)00368-0.
