Kogenate FS Uses, Dosage, and Side Effects: What Patients Should Know

Kogenate FS is a recombinant version of antihemophilic factor (also known as factor VIII), which is used to control and prevent bleeding episodes in patients with classic hemophilia (hemophilia A). Antihemophilic factor, or factor VIII, is a natural protein in the blood that’s needed to help blood make a clot. 

Patients with hemophilia usually have little to no production, or function, of FVIII. This can cause excessive bleeding as a result of an injury. Internal bleeding into joints and muscles due to trauma or surgical procedures is typical in these patients and can lead to long-term joint damage or disability. 

Kogenate FS works to raise the level of FVIII so that blood can form clots properly, and the chances of spontaneous or excessive bleeds are reduced. 

Usage or Indication

Kogenate FS is typically prescribed to children and adults with hemophilia A who either lack coagulation factor VIII or have a lower-than-normal level. The Food and Drug Administration (FDA) has approved Kogenate FS to be used in the following circumstances in people with hemophilia A:

• To treat bleeding episodes when they occur
• To manage excessive bleeding related to surgical or dental procedures 
• To prevent or reduce the frequency of bleeding episodes in children and to reduce the risk of joint damage in children with no prior joint damage
• To prevent or reduce the chances of bleeding episodes in adults with hemophilia A. 

Kogenate FS should NOT be used to treat von Willebrand disease because it does not contain von Willebrand factor.

Mode of Action

Kogenate FS (Antihemophilic Factor [Recombinant]) is produced using recombinant DNA technology. It contains an active ingredient that has a similar activity to that of the natural FVIII coagulation factor and helps the blood clot more efficiently. 

In short, Kogenate FS temporarily replaces the missing natural factor FVIII, thus giving temporary control of bleeding in hemophilia A patients. 

Kogenate FS: Dosage Forms and Strengths

Kogenate FS comes as a lyophilized powder in a single-dose vial. Each vial of Kogenate FS is labeled with the recombinant antihemophilic factor activity expressed in IU (international units) per vial. Currently, this drug is available in five different strengths:

• 250 IU
• 500 IU
• 1,000 IU
• 2,000 IU
• 3,000 IU

Kogenate FS is reconstituted in the provided diluent and should be administered within 3 hours after reconstitution. 

Dosage and Administration

The dose of Kogenate FS is recommended based on the patient’s clinical condition, age, body weight (in kg), severity of factor VIII deficiency, and location and extent of bleeding. 

The dose is first mixed with diluent and then administered as an intravenous injection (into a vein through an IV). Typically, it takes 1 to 15 minutes to infuse the whole dosage of Kogenate FS. However, your healthcare provider will determine the best administration rate for you.

1. Dosage for Routine Prophylaxis

The recommended dosing range of Kogenate FS for adult patients is 25 IU/kg three times a week. For children under 12, the recommended dose is 25 IU/kg, every other day.

2. Dosage for Control and Prevention of Bleeding Episodes

The dose of Kogenate FS depends on how severe the bleeding is and where it’s happening:

• For minor bleeds (such as minor muscle or oral bleeds): a dose of 10 to 20 IU/kg of Kogenate FS until the bleeding stops.
• For moderate bleeds (e.g., muscle and joint bleeds): a dose of 15 to 30 IU/kg every 12 – 24 hours until the bleeding stops.
• For severe bleeds (e.g., fractures, head trauma, or stomach bleeding): an initial dose of 40 to 50 IU/kg, followed by a repeated dose of 20 to 25 IU/kg, given every 8 – 12 hours until the bleeding is resolved. 

3. Dosage to Control Bleeding During or After Surgery

Kogenate FS maintains the FVIII activity levels at or above the target range to control bleeding during or after surgery. For example:

• For minor surgical procedures (e.g., tooth extraction): a dose of 15 to 30 IU/dl is administered every 12 – 24 hours to maintain FVIII activity levels between 30 – 60 IU/dl until healing is complete. 
• For major surgical procedures (e.g., hip replacement surgery or brain surgery): a dose of 50 IU/kg is administered before surgery and every 6 – 12 hours to maintain FVIII levels in the desired range until healing is complete. 

Common Side Effects of Kogenate FS:

Some side effects are minor and temporary, while some could be severe and require immediate medical attention. The most common side effects reported by >4% of people during prophylaxis trials include:

• Nausea
• Infusion-site reactions (e.g., inflammation, pain)
• Central venous access device (CVAD)-associated infections
• Rash or hives
• Itching
• Drop in blood pressure
• Lightheadedness 
• Difficulty breathing

Always consult your healthcare provider or hemophilia treatment center if you experience any side effects after taking Kogenate FS.

Contraindications and Warnings

Patients allergic to Kogenate FS or any inactive ingredients in the vial should not take this drug. 

When using Kogenate FVIII, patients may develop inhibitors (antibodies) against Factor VIII, which may stop this drug from working properly. 

Precautionary Measures You Should Take

Always consult your healthcare provider before taking Kogenate FS if you are/have:

• Pregnant or breastfeeding 
• An allergic reaction to any of the Factor VIII products 
• Taking any prescription or non-prescription medications, such as over-the-counter medications, supplements, or herbal products
• Any medical problems, like heart disease or being at risk for heart disease
• Inhibitors against factor VIII

Estimated Cost of Kogenate FS

The cost of Kogenate FS (recombinant factor VIII) varies significantly depending on the dosage strength, country, and access programs. Currently, Kogenate FS is no longer available in the U.S., as Bayer discontinued the product in 2022 due to a shift toward newer treatments like Kovaltry and Jivi. Patients should consult their healthcare provider to discuss alternatives.