What Is Vonvendi, and Why Does It Matter?
Vonvendi is a lab-made version of von Willebrand factor (VWF), a protein your body needs for blood to clot. Affecting more than 3 million people in the U.S, von Willebrand disease (VWD) is a common inherited bleeding disorder caused by either low levels or faulty von Willebrand protein, leading to frequent or hard-to-stop bleeding episodes, even from minor injuries or surgeries. It can also cause prolonged nosebleeds, heavy periods, and easy bruising that can significantly affect the quality of everyday life.
The FDA has now approved a broader use of Vonvendi to prevent and treat bleeding in adults with any type of VWD and in children with VWD to stop bleeding when needed as an “on-demand” treatment or during and after any surgery (perioperative use). Previously Vonvendi was limited to on-demand and perioperative use in adults and regular prevention only in adults with the most severe (type 3) VWD.
This approval matters because Vonvendi is the only recombinant (lab-made) VWF treatment approved for both adults and children in the U.S. Until now, children with VWD only had access to treatments made from donated human plasma. A recombinant option like Vonvendi may lower the risk for infections and offer more consistent dosing. It also stays in the body longer than some other treatments, which may mean that fewer doses are needed.
Why Was It Approved?
The expanded approval for Vonvendi was based on results from several studies in both adults and children with VWD, which showed that it helped control spontaneous bleeding episodes and bleeding associated with surgery. It also showed success to prevent bleeding episodes in adults with any type of VWD.
In studies, most bleeding episodes that weren’t related to surgery were controlled with just one dose of Vonvendi. For children with severe von Willebrand disease who had undergone surgery, bleeding control was rated excellent or good in all cases. Adults who used Vonvendi regularly to prevent bleeding had fewer spontaneous bleeding episodes.
The most common side effects reported in studies are headache, nausea, vomiting, dizziness, and itching. More serious effects include allergic reactions (such as trouble breathing or swelling). Vonvendi can also cause blood clots that can lead to serious problems such as deep vein thrombosis, heart attack, stroke, or lung clots. This risk is higher in people with certain health conditions, like low levels of a protein called ADAMTS13.
Some people may also develop antibodies (inhibitors) that block the effects of Vonvendi or factor VIII, another clotting protein.
What Do I Need to Know?
Vonvendi is given through a vein, either at a clinic or at home if you or your caregiver has been trained. The dose depends on your weight, the type and severity of your VWD, location of the bleeding, the reason for treatment, and lab results. Sometimes, your health care provider will give Vonvendi along with another clotting protein called recombinant factor VIII.
If you are using Vonvendi regularly to prevent bleeding, it’s usually given twice a week. Your health care provider will check regularly for signs of blood clots and may do some blood tests to check for any VWF and/or factor VIII inhibitors that could make the medicine less effective.
Be sure to tell your health care provider about your medical history; any allergies that you have, especially to mice or hamsters; if you have inhibitors to VWF or factor VIII; and all the medicines you are taking, including over-the-counter products, vitamins, and supplements. Inform your health care provider if you are pregnant, planning to become pregnant, or breastfeeding as it is not known if Vonvendi can harm your baby or pass into breast milk.
Do not use Vonvendi if you’ve had a life-threatening allergic reaction to it or any of its ingredients, including proteins from mice or hamsters. Signs of a serious allergic reaction include a rash, chest tightness, trouble breathing, or fainting. If you notice any of these, stop using the medicine and contact your health care provider at once. Call your health care provider right away if bleeding is not controlled after using Vonvendi.