Xiaflex contains the active ingredient collagenase clostridium histolyticum, which includes two types of microbial collagenases, Collagenase AUX-I and AUX-II. It is supplied as a sterile lyophilized powder for reconstitution and is administered as an intralesional injection. The formulation comes in single-use vials containing 0.9 mg of the active ingredient, along with hydrochloric acid, sucrose, and tromethamine as key inactive ingredients. Xiaflex is intended for injection into a Dupuytren’s cord or a Peyronie’s plaque.

How should I use this medication?

This medication is injected into the affected area. It is given by your care team in a hospital or clinic setting. A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time. Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once. NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

Keep appointments for follow-up doses. It is important not to miss your dose. Call your care team if you are unable to keep an appointment.

Where should I keep my medication?

This medication is given in a hospital or clinic. It will not be stored at home.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible: -Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat -Feeling faint or lightheaded -Skin infection—skin redness, swelling, warmth, or pain -Severe back pain, chest pain, headache, trouble breathing after injection -Snap or pop that you feel or hear, severe pain, numbness, swelling, or bruising of or trouble moving in area where injected Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome): -Pain, redness, or irritation at injection site

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions: -Bleeding disorder -An unusual or allergic reaction to collagenase, other medications, foods, dyes, or preservatives -Pregnant or trying to get pregnant -Breast-feeding

What may interact with this medication?

-Aspirin and aspirin-like medications -Certain medications that treat or prevent blood clots, such as warfarin, enoxaparin, dalteparin, apixaban, dabigatran, rivaroxaban

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Your condition will be monitored carefully while you are receiving this medication. If medication is for Dupuytren's Contracture, visit your care team 1 to 3 days after the injection. Until you visit your care team, do not flex or extend the fingers of your hand that was injected. Do not touch your finger that was injected. Elevate your hand until bedtime. Do not perform activity with the injected hand until you are told that it is ok. Follow any instructions about wearing a splint or performing finger exercises. Contact your care team as soon as possible if you get increasing redness or swelling in the hand, have numbness or tingling in the treated finger, or have trouble bending the finger after the swelling goes down. If medication is for Peyronie's disease, do not have sex between the first and second injections. Wait 4 weeks after the second injection and when there is no more pain or swelling in the penis to have sex. Avoid using vacuum erection devices during treatment with this medication. Try to avoid straining stomach muscles such as during bowel movements. Your care team will give you instructions on how to perform modeling activities at home. Contact your care team as soon as possible if you have severe pain or swelling in the penis, severe purple bruising and swelling of the penis, trouble passing urine, blood in urine, popping or cracking sound form the penis, or sudden loss of ability to maintain an erection.

What are the most serious risks of this medication?

Getting this treatment may cause severe damage to your penis. A blood vessel in your penis could break. The blood would need to be drained from under the skin. Also, you could get a penis fracture. A fracture requires surgery, but the damage might not get better. Call your healthcare provider right away if you have any of these symptoms: popping sound or feeling in an erect penis; suddenly can not maintain an erection; pain in your penis; purple bruising and swelling of your penis; difficulty urinating or blood in the urine.