Fitusiran may cause blood clots. Your doctor will monitor you carefully if you are at risk for blood clots. If you experience any of the following symptoms, call your doctor immediately or get emergency medical care: swelling, pain or redness in arms or legs; coughing up blood; shortness of breath; severe chest pain or tightness of the chest; fast heart rate; feeling faint or fainting; severe or ongoing headache; difficulty speaking or understanding what is being said; feel confused; numbness or weakness in your face, arms or legs; eye pain or swelling, or sudden loss or changes in your vision.
Fitusiran may also cause gallbladder problems. Tell your doctor if you have or have ever had gallbladder disease. If you experience any of the following symptoms, call your doctor immediately : abdominal pain, indigestion, nausea, or vomiting.
Keep all appointments with your doctor and the laboratory. Your doctor will order certain tests to check your body's response to fitusiran.
You will be given the Medication Guide when you begin treatment with Fitusiran and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit https://www.fda.gov/Drugs/DrugSafety/ucm085729.htm to obtain the Medication Guide.Why is this medicine prescribed?
Fitusiran is used to prevent or reduce the frequency of bleeding episodes in people with certain types of hemophilia. Fitusiran is in a class of medications called antithrombin-directed small interfering RNA (siRNA). It works by by reducing the amount of a protein in the body to improve blood clotting.
Are there other uses for this medicine?
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
How should this medicine be used?
Fitusiran comes as a solution in prefilled pens and vials to inject to inject subcutaneously (under the skin). It should be given once every 2 months. Your doctor will check your blood's clotting ability with a lab test at specific times during your treatment.
Use fitusiran injection exactly as directed. Do not use more or less of it or give it more often than prescribed by your doctor.
You doctor will start you on an initial dose of fitusiran. The dosage and frequency of use may be changed based on your laboratory results.
Your healthcare provider will show you or your caregiver how to prepare and give a subcutaneous dose of an fitusiran injection. Carefully read the manufacturer's instructions for use that comes with the medication. These instructions describe how you or a caregiver should inject a dose of fitusiran injection. Be sure to ask your pharmacist or doctor if you have any questions about how to inject this medication.
You can inject fitusiran in your thigh or stomach area, except for a 2 inch the area around your belly button. A caregiver can also give the injection into your upper arm. Allow the pen to warm to room temperature for at least 30 minutes before injecting if the pen was stored in the refrigerator.
What special precautions should I follow?
Before using fitusiran,
- tell your doctor or pharmacist if you are allergic to this medication, any part of this medication, or any other medications, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while using fitusiran. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had liver disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using fitusiran, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are using fitusiran.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do if I forget to take a dose?
If you miss a dose of fitusiran on your scheduled day, give the dose as soon as possible. Then resume your dosing schedule from the last dose, as instructed by your healthcare provider.
What should I do in case of overdose?
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help . If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.
What side effects can this medicine cause?
Fitusiran may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- signs of infection such as sore throat, runny or stuffy nose, cough, fever, chills, and tiredness
Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately or get emergency medical treatment:
- nausea, vomiting, loss of appetite, pain in the upper right part of the stomach, flu-like symptoms, dark urine, yellowing of the skin or eyes, or lack of energy
Fitusiran may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( https://www.fda.gov/Safety/MedWatch ) or by phone ( 1-800-332-1088).What should I know about storage and disposal of this medication?
Keep this medication in the container it came in and out of reach of children. Store it away from light and heat; do not shake. Do not freeze or place in direct sunlight.
Store unused fitusiran prefilled pens in the refrigerator (36°F to 46°F [2°C to 8°C]) in the original carton. A fitusiran prefilled pen can be stored at room temperature (59°F to 86°F [15°C to 30°C]) for up to 3 months as long as it does not exceed the expiration date on the label. After storing at room temperature, do not return the pens to the refrigerator.
Store unused fitusiran vials in the refrigerator (36°F to 46°F [2°C to 8°C]) or at room temperature in the original carton. After storing at room temperature, do not return the vials to the refrigerator.
Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.What other information should I know?
Keep all appointments with your doctor and the laboratory.
Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking fitusiran.
Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.
Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.