Tretten (Catridecacog): Uses, Dosage, Side Effects, and Cost

Congenital factor XIII A-subunit deficiency can cause life-threatening bleeds. Tretten is a once-monthly therapy for this rare bleeding disorder. Learn about the mechanism, precautions, proper use, side effects, and cost. 

Tretten Introduction and Uses

Tretten is a brand-name prescription product. It contains catridecacog, a recombinant form of coagulation factor XIII A-subunit. Tretten belongs to a drug class known as coagulation factors or hemostatics. 

Tretten is produced using recombinant DNA technology and is not derived from human plasma. 

A healthcare provider may prescribe this medication to prevent bleeding in children and adults with congenital factor XIII (FXIII) A-subunit deficiency. 

Congenital factor XIII (FXIII) A-subunit deficiency is a rare inherited bleeding disorder. It is estimated to affect 1 in every 1 to 3 million people. In people with this disorder, the blood doesn’t clot properly, leading to a higher risk of [1]:

• Life-threatening bleeds (most notably, spontaneous bleeding within the brain)
• Delayed wound healing 
• Recurrent spontaneous abortion in women 

Currently, Tretten is the first and only recombinant therapy for people with congenital factor XIII (FXIII) A-subunit deficiency. All other approved treatments are derived from plasma. 

This medication shouldn’t be used to treat another similar bleeding disorder called congenital factor XIII B‑subunit deficiency.

Note: Tretten is sold under the brand name NovoThirteen in the EU, Switzerland, and Australia. 

Tretten Mechanism of Action

Factor XIII A-subunit plays a crucial role in blood clotting. When bleeding occurs, the body forms a mesh of fibrin proteins to create a blood clot. Activated factor XIII helps strengthen and stabilize the clot by linking fibrin strands together. 

When you have factor XIII A-subunit deficiency, blood clots become unstable and fragile. As a result, blood clots may break down too easily, increasing the risk of potentially life-threatening bleeding [2].

Tretten is a lab-created protein that works the same way as the naturally occurring factor XIII-A subunit in the body. Thus, it helps stabilize clots and prevent bleeding. 

Important Tretten Warnings and Precautions

Allergic Reactions

This medication may cause allergic reactions. Seek emergency medical care if you experience:

• Rash
• Chest tightness
• Wheezing

You should not use this medication if you have a history of allergic reactions to this product or any product component. 

Inhibitor Production

In some cases, your body can make proteins called “inhibitors” that can stop this medication from working as well as it should. 

If your immune system makes inhibitors, Tretten may become less effective. Your healthcare provider may test for inhibitors if the medication stops working as expected or your factor XIII activity is lower than expected. 

Risk of Blood Clots

If you have a higher risk of blood clots, your healthcare provider will monitor you after administering Tretten. Do not use Tretten together with recombinant factor VIIa, as this combination may increase the risk of blood clots. 

Before Taking Tretten

Before you receive your first dose, inform your provider if you:

• Are pregnant, think you might be pregnant, or are planning to get pregnant 
• Are breastfeeding
• Have had blood clots in the past

It is unclear whether this medication is safe and effective during labor and delivery.

Tretten Dosage

The recommended dose of Tretten for routine bleeding prevention is 35 IU/kg of body weight, administered once every 28 days. Your healthcare provider may monitor factor XIII activity and adjust treatment to maintain trough FXIII activity at or above 10%. 

Tretten Administration and Proper Use

• Your healthcare provider will inject the reconstituted medicine into your vein once monthly. 
• The dose is individualized based on your body weight. 
• You may inject it yourself after receiving instructions from your healthcare provider.
• Strictly follow the instructions about proper use, dose, and techniques for administration. If you are unclear about anything, ask your healthcare provider for help. 
• Tretten comes as a powder, which must be mixed with sterile water before injection. The sterile water comes in a separate vial. 
• If you need a smaller dose, you may dilute the medicine with 0.9% sodium chloride. 
• Administer Tretten as a slow intravenous injection at a rate not exceeding 1–2 ml per minute, following your healthcare provider’s instructions. 
• Do not mix Tretten with other infusion solutions or administer it as an IV drip. 
• Open the package only when you are ready to administer the medicine. 
• Don’t use expired or damaged medicine. 

Tretten Storage

Before Reconstitution

• Refrigerate between 36 °F and 46 °F. 
• Don’t freeze. 
• Protect from direct light until ready for reconstitution.

After Reconstitution

• Use the reconstituted medicine immediately. 
• You may store the reconstituted medicine at room temperature (up to 77 °F) or in a refrigerator (avoid freezing) for up to 3 hours. 
• If 3 hours have passed, throw away any reconstituted medicine. 

Tretten Side Effects

Allergic Reactions

Seek emergency medical care if you experience any of the following signs and symptoms after receiving Tretten:

• Shortness of breath
• Rash
• Itching
• Redness of the skin
• Fainting
• Dizziness

Blood Clots

Seek emergency medical care if you experience any of the following signs and symptoms after receiving Tretten:

• Pain, swelling, warmth, redness, or a lump in the legs or arms
• Chest pain
• Sudden severe headache 
• Fainting

Call your doctor immediately if you have any unexpected bleeding. 

Other side effects can include:

• Pain in the arms or legs
• Headache
• Pain at the injection site
• Increased D-dimer levels (a laboratory finding related to blood clot formation and breakdown) 

Tretten Cost and Financial Assistance

Tretten costs vary depending on your prescribed dose, insurance coverage, and pharmacy. Your insurance plan may require prior authorization before covering treatment. 

Novo Nordisk, the manufacturer of Tretten, offers financial support to eligible patients. Contact us if you are interested in applying for copay assistance for Tretten.