Inovio's Investigational HPV Therapy Shows Promise With FDA Regulatory Acceptance

Inovio Pharmaceuticals has cleared a major regulatory milestone as the FDA formally accepted its Biologics License Application for INO-3107, a novel immunotherapy targeting recurrent respiratory papillomatosis (RRP) in adult patients. The agency assigned an October 30, 2026 review completion date and signaled it does not anticipate convening an advisory committee for this submission. However, the acceptance letter noted that additional substantiation may be needed to support eligibility for the accelerated approval pathway under which the therapy is currently being evaluated.

Clinical Evidence Demonstrates Significant Surgical Reduction

The regulatory submission rests on compelling clinical trial results. Among RRP patients who had undergone multiple prior surgeries, INO-3107 demonstrated substantial benefit: 72% achieved a 50-100% decrease in the number of surgical procedures during year one following treatment. The long-term follow-up analysis proved even more encouraging, with 86% of patients sustaining clinical improvements throughout the second year without receiving additional doses. Notably, half of these patients required no surgical intervention whatsoever during this extended observation period.

These findings, published in Nature Communications and The Laryngoscope, underscore the unmet medical need in RRP management, where conventional surgical intervention remains the standard approach despite its inherent limitations and risks to vocal cord integrity.

Understanding RRP and the Therapeutic Approach

Recurrent respiratory papillomatosis is a rare but severely disabling condition predominantly caused by HPV strains 6 and 11. The disease manifests as benign growths in the respiratory tract that progressively obstruct airways and compromise vocal function. Repeated surgical removal remains the current treatment standard, yet the high recurrence rate necessitates multiple interventions over time, exposing patients to cumulative procedural risks and quality-of-life complications.

INO-3107 operates through a distinct mechanism: it stimulates antigen-specific T-cell immunity against HPV-6 and HPV-11, targeting virus-infected cells to potentially suppress or arrest papilloma proliferation. Clinical safety profiling revealed favorable tolerability, with predominantly mild adverse effects including localized injection reactions and transient fatigue.

Regulatory Status and Financial Positioning

The therapy carries both Orphan Drug and Breakthrough Therapy designations in the United States, reflecting the regulatory pathway acceleration for treatments addressing serious rare conditions with meaningful clinical advantages.

Inovio ended the third quarter of 2025 with approximately $50.8 million in available liquidity (cash, equivalents, and short-term investments), positioning the company to fund ongoing operations into mid-2026.

Market Reaction and Stock Performance

Despite the FDA’s formal acceptance, investors reacted cautiously, with shares declining amid concerns regarding the agency’s indication that additional supporting documentation may be required to substantiate accelerated approval qualification. This conditional stance introduced perceived uncertainty regarding the regulatory timeline. Over the past 12 months, INO has fluctuated between $1.30 and $2.98. Pre-market trading showed the stock at $1.85, reflecting a 19.21% decline from the previous close.