SELECTED IMPORTANT SAFETY INFORMATION: You should not use KOVALTRY® if you are allergic to rodents (like mice and hamsters) or any ingredients in KOVALTRY®CONTINUE READING BELOW >

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Exploring the LEOPOLD I trial

KOVALTRY®  was studied and designed for you—and dosed based on people's needs in a trial called LEOPOLD I1


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There were 62 previously treated adolescents and adults  (aged 12 to 65 years) with severe hemophilia A in LEOPOLD I, studied for 1 year.1

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Doctors studied annual bleed rate (ABR) ABR, or annual bleed rate, is the number of bleeds a person would experience in a year. , choosing either 2x/week prophylaxisProphylaxis treatment in hemophilia A is regular treatment to reduce bleeding, before bleeds actually happen. (18 people), or 3x/week prophylaxis (44 people) based on people's needs.1

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People who were chosen to start a 2x/week regimen had a prior history of fewer bleeds and a lower percentage of target joints  than people chosen for a 3x/week regimen.2

Doctors chose a dose based on the individual person's needs. They didn't need to test pharmacokinetic activity (drug activity in the body) to find the right dose.1,2


KOVALTRY® is a medicine used to replace clotting factor (Factor VIII or antihemophilic factor) that is missing in people with hemophilia A.

KOVALTRY is used to treat and control bleeding in adults and children with hemophilia A. KOVALTRY can reduce the number of bleeding episodes in adults and children with hemophilia A when used regularly (prophylaxis). Your healthcare provider may give you KOVALTRY when you have surgery.

KOVALTRY is not used to treat von Willebrand Disease.


You should not use KOVALTRY if you are allergic to rodents (like mice and hamsters) or any ingredients in KOVALTRY.

Tell your healthcare provider if you have heart disease or are at risk for heart disease.

The common side effects of KOVALTRY are fever, headache, and rash, in addition to inhibitors in patients who were not previously treated or minimally treated with Factor VIII products.

Your body may make antibodies, called “inhibitors” against KOVALTRY, which may stop KOVALTRY from working properly. If your bleeding is not adequately controlled, it could be due to the development of Factor VIII inhibitors. Consult with your healthcare provider to make sure you are carefully monitored with blood tests for the development of inhibitors to Factor VIII.

Allergic reactions may occur with KOVALTRY. Call your healthcare provider right away and stop treatment if you get tightness of the chest or throat, dizziness, decrease in blood pressure, and nausea.

Tell your healthcare provider about any side effect that bothers you or that does not go away.

Call your healthcare provider right away if bleeding is not controlled after using KOVALTRY.

For additional important risk and use information, please see full Prescribing Information.

References: 1. KOVALTRY® [prescribing information]. Whippany, NJ: Bayer HealthCare LLC; 2021. 2. Data on file. Bayer HealthCare Pharmaceuticals, Inc; 2016.