PAPZIMEOS (Zopapogene Imadenovec) for Recurrent Respiratory Papillomatosis (Laryngeal Papillomas)

Papzimeos (zopapogene imadenovec) is a targeted immunotherapy developed for the treatment of recurrent respiratory papillomatosis (RRP), a condition characterized by the growth of benign papillomas in the larynx caused by the human papillomavirus (HPV). The therapy is designed to stimulate the immune system to recognize and eliminate HPV-infected cells, thereby reducing disease activity.

Mechanism of Action

Papzimeos functions by enhancing immune recognition of HPV. While most individuals exposed to HPV successfully clear the virus, a subset of otherwise healthy individuals appears to have an immune response that tolerates or fails to adequately recognize the virus—as though they have a “chink” in an otherwise strong armor. In these patients,

Papzimeos aims to “teach” the immune system to “see” and neutralize the human papilloma virus.

Treatment Goals

The primary therapeutic goals of Papzimeos include:

1. Reducing the frequency of surgical procedures required to remove papillomas;
2. In a best-case scenario, eliminating the need for surgery;
3. Improving voice quality.

While this new treatment has shown high rates of success in a group of patients with RRP, response cannot be guaranteed for any individual.

Treatment Setting

Papzimeos is not currently available for routine administration in general medical offices or pharmacies. Instead, it will be offered by specialized laryngology centers that have experience managing large numbers of RRP patients. Such a center will of course have equipment for detailed laryngeal examination; surgical capabilities (office or operating room facilities and a laryngologist (ENT surgeon); and an ultra-low temperature freezer.

Treatment Protocol

Treatment is delivered as a series of four injections:

• Visit 1: Occurs at the time of surgical debulking or within a few days after. Laryngeal examination, then first injection
• Visit 2 at 2 weeks: Laryngeal examination, then injection
• Visit 3 at 6 weeks: Laryngeal examination, then injection
• Visit 4 at 12 weeks: Laryngeal examination, then injection.

If papilloma regrowth occurs during the treatment period (which is not expected), additional surgical debulking may be required.

What Are Potential Side Effects?

At the site of injection, transient mild redness, tenderness, swelling, and warmth may be seen. This is treated with cold compresses, gentle arm movement, etc.

Some patients experience may experience mild, flu-like symptoms within 24–48 hours, such as fatigue, low-grade fever, chills, headache, muscle aches, mild nausea.

This would be treated with acetaminophen, hydration, rest, etc. All these side effects reflect immune system activation and can be viewed therefore in a positive light.

What Have Studies Shown so Far?*

*infographic retrieved from https://papzimeos.com/