Caplacizumab is used to treat acquired thrombotic thrombocytopenic purpura (aTTP) in adults. Caplacizumab is given together with immunosuppressant medication and plasma exchange (transfusion).

Caplacizumab may also be used for purposes not listed in this medication guide.

Caplacizumab can increase your risk of bleeding. Call your doctor if you have unusual bruising or bleeding, or any bleeding that will not stop.

Caplacizumab is injected under the skin, or given as an infusion into a vein. A healthcare provider will give your first dose and may teach you how to properly use the medication by yourself.

Caplacizumab and plasma exchange are usually started on the same day. Caplacizumab is then continued for 30 days or longer after your last daily plasma exchange.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you don't understand all instructions.

Caplacizumab must be mixed with a liquid (diluent) before using it. When using injections by yourself, be sure you understand how to properly mix and store the medicine.

Prepare an injection only when you are ready to give it. Do not use if the medicine looks cloudy, has changed colors, or has particles in it. Call your pharmacist for new medicine.

If you need surgery, dental work, or a medical procedure, you may need to stop using caplacizumab for at least 7 days ahead. Tell any doctor or dentist who treats you that you currently use this medicine.

Store caplacizumab in its original carton in the refrigerator. Protect from light and do not freeze.

You may store an unopened caplacizumab carton at room temperature for up to 2 months. Keep track of when you took the carton out of the refrigerator, and do not return it to the refrigerator once the medicine has reached room temperature.

If you cannot use the mixed medicine right away, store it in the refrigerator and use it within 4 hours.

Each vial (bottle) is for one use only. Throw it away after one use, even if there is still medicine left inside.

Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

Usual Adult Dose for Idiopathic (Immune) Thrombocytopenic Purpura:

Initial dose:
-First day of treatment: 11 mg bolus IV injection at least 15 minutes prior to plasma exchange followed by an 11 mg subcutaneous injection after completion of plasma exchange on Day 1

Maintenance dose:
-Subsequent days of treatment during daily plasma exchange: 11 mg subcutaneous injection once a day following plasma exchange
-Treatment after plasma exchange period: 11 mg subcutaneous injection once a day continuing for 30 days following the last daily plasma exchange. If after initial treatment course sign(s) of persistent underlying disease such as suppressed ADAMTS13 activity levels remain present, treatment may be extended for a maximum of 28 days.

Comments:
-Discontinue this drug if the patient experiences more than 2 recurrences of acquired thrombotic thrombocytopenic purpura (aTTP) during treatment with this drug.
-Withhold this drug 7 days prior to elective surgery, dental procedures, or other invasive interventions.

Use: Treatment of patients with acquired thrombotic thrombocytopenic purpura (aTTP) in combination with plasma exchange and immunosuppressive therapy

You should not use caplacizumab if you are allergic to it.

Tell your doctor if you have ever had a bleeding or blood clotting disorder such as hemophilia.

Follow your doctor's instructions about using caplacizumab if you are pregnant. Caplacizumab may increase the risk of bleeding in both mother and baby. However, the benefit of treating aTTP in the mother during pregnancy may outweigh those risks. Tell your doctor right away if you become pregnant.

It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.

If you miss a dose while you are receiving daily plasma exchanges: Use the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not use two doses at one time.

If you miss a dose and are no longer receiving plasma exchanges: Use the medicine as soon as you can, but skip the missed dose if you are more than 12 hours late for the dose. Do not use two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose can cause excessive bleeding.

Avoid activities that may increase your risk of bleeding or injury. Use extra care to prevent bleeding while shaving or brushing your teeth.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Caplacizumab may cause serious side effects. Call your doctor at once if you have:

• easy bruising or bleeding (nosebleeds, bleeding gums);

• unusual vaginal bleeding;

• any bleeding that will not stop; or

• signs of stomach bleeding--bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds.

Common side effects of caplacizumab may include:

• nosebleeds, bleeding gums; or

• headache.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your doctor about all your other medicines, especially:

• a blood thinner--warfarin, Coumadin, Jantoven; or

• any medicine used to treat or prevent blood clots.

This list is not complete. Other drugs may affect caplacizumab, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.