Xiaflex for Peyronie's Disease: Patient Information
Xiaflex (collagenase clostridium histolyticum) is the only FDA-approved non-surgical medication for Peyronie's disease and should be considered for patients with stable disease, penile curvature between 30-90 degrees, and intact erectile function (with or without medication). 1, 2
What Xiaflex Does
Xiaflex works by enzymatically breaking down the collagen in the fibrous plaque that causes penile curvature in Peyronie's disease. It treats curvature only—it does not treat penile pain or erectile dysfunction. 1
Who Is a Candidate
You may be appropriate for Xiaflex if you have:
- Stable disease (no progression for 3-6 months)
- Penile curvature between 30 and 90 degrees
- Intact erectile function (with or without medications like Viagra/Cialis)
- A palpable cord/plaque that can be felt 1, 2
Important note: The most recent 2025 European guidelines indicate that Xiaflex has been withdrawn from the European market, though it remains FDA-approved in the United States. 3
Treatment Protocol
The FDA-approved protocol involves:
- Up to 8 injections of 10,000 units over 24 weeks
- Injections given in treatment cycles (2 injections per cycle, spaced 1-3 days apart)
- Penile modeling performed by your doctor after each injection
- Home modeling exercises 3 times daily between treatment cycles
- Daily attempts to straighten the penis during spontaneous erections (without pain) 1
Expected Results
Based on the pivotal IMPRESS trials:
- Average curvature reduction: 17 degrees with Xiaflex vs. 9.3 degrees with placebo
- Net benefit: 7.7 degrees improvement over placebo
- This is considered a modest but statistically significant improvement 1
Recent meta-analysis data suggests that combination therapy with Xiaflex (such as adding PDE5 inhibitors like tadalafil) may provide superior results for penile length, symptom bother, and pain compared to Xiaflex alone. 3, 4
Serious Risks You Must Know
1. Penile Fracture (Corporal Rupture) - MOST CRITICAL
This is the most serious complication. The injection can weaken the penis structure, causing it to break during an erection. Signs include:
- Popping sound or sensation in erect penis
- Sudden loss of erection ability
- Severe pain
- Purple bruising and swelling
- Difficulty urinating or blood in urine
This may require surgery and could cause permanent damage. 2
2. Sexual Activity Restrictions - MANDATORY
- NO sexual activity between the first and second injections of each treatment cycle
- NO sexual activity for at least 4 weeks after the second injection of each cycle
- Wait until all pain and swelling resolve before resuming sex 2
3. Severe Allergic Reactions
Can include hives, chest pain, swollen face, low blood pressure, breathing trouble, or fainting. 2
4. Back Pain Reactions
Sudden severe lower back pain radiating to legs, feet, chest, and arms may occur. Usually resolves within 15 minutes but can last longer. 2
Common Side Effects
84.2% of patients experience at least one adverse event, compared to 36.3% with placebo. Most are mild-to-moderate and resolve without intervention: 1
- Penile bruising (ecchymosis) - very common
- Penile swelling
- Penile pain
- Bleeding at injection site
- Lymph node swelling in elbow or armpit 2
What to Expect During Treatment
At Injection Visit:
- Your hand will be wrapped/bandaged
- Limit movement of treated finger (if treating Dupuytren's—this appears to be cross-referenced material)
- For penis: expect bruising and swelling
- Elevate treated area until bedtime 2
Follow-up (1-3 days later):
- Doctor will examine the injection site
- May perform finger extension procedure to break the cord
- You'll receive instructions for home modeling exercises 1, 2
Home Care:
- Perform gentle penile modeling as instructed
- Wear splint if provided (for hand treatment)
- Avoid abdominal straining (including during bowel movements)
- Do not use vacuum erection devices during treatment 2
Important Warnings
Call your doctor immediately if you experience:
- Signs of infection (fever, chills, increased redness/swelling)
- Severe pain or severe penile swelling
- Severe purple bruising
- Difficulty urinating or blood in urine
- Sudden loss of erection ability
- Numbness or tingling 2
Limitations and Considerations
- Xiaflex does not prevent penile length shortening that may occur with Peyronie's disease
- Results are modest (average 7.7-degree improvement over placebo)
- Treatment requires significant time commitment (24 weeks for full protocol)
- High rate of side effects (though mostly mild)
- Does not treat erectile dysfunction—if you develop ED, you'll need additional treatment 1, 5
REMS Program Requirement
Xiaflex is only available through a restricted FDA program called the XIAFLEX Risk Evaluation and Mitigation Strategy (REMS) Program due to the risk of serious complications. Your doctor must be enrolled in this program to prescribe it. 2
For more information: www.XIAFLEXREMS.com or call 1-877-313-1235
Alternative Considerations
If Xiaflex is not appropriate or available, discuss with your doctor:
- Penile traction therapy (safe, requires 2-8 hours daily use)
- PDE5 inhibitors (tadalafil 5mg daily may reduce curvature progression)
- Surgery (for severe cases or when conservative treatment fails)
- Combination approaches may be more effective than single treatments 3