This study tests a cream called Ruxolitinib for people with Prurigo Nodularis (PN). PN is a skin condition that causes very itchy bumps. The study will last about 12 weeks where neither the doctors nor the participants will know who receives the real cream or a fake one (this is called "double-blind"). After this, there is a 40-week period where everyone will know they are using the real cream ("open label"). Finally, there will be a 30-day checkup to ensure safety.

To join, you must have had PN for at least 3 months, with at least 6 itchy spots on different parts of your body. There are also some conditions that prevent participation, like other skin problems, certain medications, or being pregnant.

• Length of Study: 82 weeks total (includes treatment and follow-up).
• Visits Needed: Regular check-ups throughout the study.
• Risks: Potential side effects from the cream; discuss with your doctor.