Understanding PK
The Role of PK in Individualizing Your Hemophilia A Treatment
phar-ma-co-ki-net-ics
Pharmacokinetics is the study of the bodily absorption, distribution, metabolism and elimination of drugs.
Absorption
How drugs are taken into your body
Distribution
How drugs move around in your body
Metabolism
How drugs are broken down in your body
Elimination
How drugs are eliminated from your body
Why is PK Testing Important?
PK testing allows your doctor to understand your unique PK profile and create a treatment plan that matches your needs. Talk to your physician about obtaining your PK profile.
How Does PK Testing Help with Your Treatment?
The aim of hemophilia A treatment is to continuously maintain factor VIII at high enough levels with regular infusions to reduce the frequency of bleeding episodes. This is known as prophylaxis, which is the standard of care for treatment of hemophilia A in the United States.
The amount of factor VIII (the drug dose) and the frequency at which it must be given to prevent spontaneous bleeds varies from person to person. PK testing allows doctors to better understand how factor VIII levels behave in your body, so they can better individualize and fine tune your treatment by defining the right dose and infusion frequency for you.
Meet Sam
Sam, a teenage boy, has been selected for his school swimming team but is worried about his risk of bleeds if he trains more regularly.
PK testing could help to adjust his infusion schedule so that his levels of factor VIII are high enough on the days when he wants to train.*
*These are fictional scenarios for illustration only. Treatment decisions should be made by a physician on an individual basis.
PK testing involves working with your physician to measure factor VIII levels in blood samples taken from you over a period of time. With PK testing, your doctor defines your PK profile.
Like a fingerprint, a PK profile is unique for every person with hemophilia A – there is nobody else quite like you! This unique PK profile can be used to make sure that the drug is given in the right amount (the drug dose) and at the right frequency.
Meet Marco
Marco is a 35-year-old man who loves the outdoors and hiking. Together with his doctor, they have been having difficulty finding the right infusion schedule to prevent bleeds.
PK testing could help him find the right infusion frequency to match his needs.*
*These are fictional scenarios for illustration only. Treatment decisions should be made by a physician on an individual basis.
How Do You Get Your PK Profile?
Obtaining Your PK Profile:
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01First, your doctor takes blood samples after one or more infusions of factor VIII during your normal treatment regimen.
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02Then, the amount of factor VIII in each blood sample is measured by your doctor.
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03Your doctor will generate your unique PK profile based on your measurements.
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04Together, you and your doctor determine the best treatment for you based on your needs: the right amount of factor to infuse each time (drug dose) and the right frequency of infusions for you.
Just like your personal profile with your name, address, date and place of birth, your PK profile is defined by a set of characteristics, unique to you.
Let's break them down:
Peak
The highest level of factor that can be obtained in the bloodstream after infusion.
Area Under the Curve (AUC)
The total amount of factor that is absorbed and distributed in your bloodstream over a period of time. It is used by your doctor to define the right dose for you.
Half-Life
The amount of time it takes for factor levels to get reduced by half (50%) of what they originally were right after your infusion. It helps your doctor understand how long factor remains active in your body.
Clearance
The speed at which factor is eliminated from your body. The higher the clearance, the faster your body breaks down and eliminates factor. Clearance helps your doctor define the right frequency of infusion for you.
Trough Level
The minimum factor level that your doctor sets individually with you based on your personal needs. The trough level indicates to your doctor when you should take another infusion
Your PK Profile Helps You Choose the Right Factor VIII Product for You.
Think of your factor VIII product as your car, and the PK profile (peak, area under the curve, half-life, clearance, and trough level) as the fuel for your car.
Peak
Area Under the Curve (AUC)
Half-Life
Clearance
Trough Level
Peak
Area Under the Curve (AUC)
Half-Life
Clearance
Trough Level
When going for a drive, you ideally want to have a full tank of gas (peak) and more gas available for your drive over time (higher AUC). You also would want it to take longer for the gas in your tank to go from a full tank to a half tank (longer half-life), and for your car to burn through gas slower (slower clearance). Additionally, you want to make sure you have at least a minimum amount of fuel in your tank to avoid running out of gas (right trough level).
Talk to your physician about obtaining your PK profile.
INDICATIONS
Jivi is an injectable medicine used to replace clotting factor (Factor VIII or antihemophilic factor) that is missing in people with hemophilia A.
Jivi is used to treat and control bleeding in previously treated adults and adolescents (12 years of age and older) with hemophilia A. Your healthcare provider may also give you Jivi when you have surgery. Jivi can reduce the number of bleeding episodes in adults and adolescents with hemophilia A when used regularly (prophylaxis).
Jivi is not for use in children below 12 years of age or in previously untreated patients.
Jivi is not used to treat von Willebrand disease.
IMPORTANT SAFETY INFORMATION
You should not use Jivi if you are allergic to rodents (like mice and hamsters) or to any ingredients in Jivi.
Tell your healthcare provider about all of your medical conditions that you have or had.
Tell your healthcare provider if you have been told that you have inhibitors to Factor VIII.
Allergic reactions may occur with Jivi. Call your healthcare provider right away and stop treatment if you get tightness of the chest or throat, dizziness, decrease in blood pressure, or nausea.
Allergic reactions to polyethylene glycol (PEG), a component of Jivi, are possible.
Your body can also make antibodies, called “inhibitors,” against Jivi, which may stop Jivi from working properly. Consult your healthcare provider to make sure you are carefully monitored with blood tests for the development of inhibitors to Factor VIII.
If your bleeding is not being controlled with your usual dose of Jivi, consult your doctor immediately. You may have developed Factor VIII inhibitors or antibodies to PEG and your doctor may carry out tests to confirm this.
The common side effects of Jivi are headache, cough, nausea, and fever.
These are not all the possible side effects with Jivi. Tell your healthcare provider about any side effect that bothers you or that does not go away.
For additional important risk and use information, please see the full Prescribing Information.
