Onpattro a double-stranded small interfering ribonucleic acid (siRNA), formulated as a lipid complex injection.

Onpattro is a prescription medicine used to treat adults with polyneuropathy of hereditary transthyretin-mediated amyloidosis (hATTR) (damage of multiple nerves throughout the body).

Onpattro is given by intravenous (IV) infusion.

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Onpattro is given as an infusion into a vein. A healthcare provider will give you this injection once every 3 weeks.

This medicine must be given slowly, and the infusion can take about 80 minutes to complete.

Tell your caregivers if you feel any burning, pain, or swelling around the IV needle when Onpattro is injected.

You may be given other medications to help prevent serious side effects or an infusion reaction.

Your doctor may have you take vitamin A while you are using Onpattro. Take only the amount of vitamin A your doctor has prescribed, especially if you are pregnant. An overdose of vitamin A can cause vision problems or other serious side effects.

Call your doctor at once if you have vision problems (especially at night) while you are taking Onpattro.

Onpattro doses are based on weight. Your dose needs may change if you gain or lose weight.

You may need frequent medical tests. Even if you have no symptoms, tests can help your doctor determine if this medicine is effective. You may also need frequent eye exams.

Usual Adult Dose for Amyloidogenic Transthyretin Amyloidosis:

Dosing is based on actual body weight; premedication should be given at least 60 minutes prior to the start of the infusion

Weight less than 100 kg: 0.3 mg/kg via IV infusion every 3 weeks
Weight 100 kg or greater: 30 mg via IV infusion every 3 weeks

Initial infusion rate should be approximately 1 mL/min for the first 15 minutes, then increase to approximately 3 mL/min for the remainder of the infusion; in the event of an infusion related reaction, the duration of infusion may be extended; see administration advice for infusion instructions

PREMEDICATION: Administer on day of infusion at least 60 minutes prior to start of infusion:
-Acetaminophen 500 mg orally
-IV corticosteroid (e.g., dexamethasone 10 mg or equivalent)
-IV H1 blocker (e.g. diphenhydramine 50 mg or equivalent)
-IV H2 blocker (e.g., ranitidine 50 mg or equivalent)

Comments:
-Premedications are required to reduce the risk of infusion related reactions (IRR).
-If IV premedications are not available or not tolerated, oral equivalents may be used
-If patients are tolerating the infusion, but experiencing adverse reactions to corticosteroid premedication, reduce corticosteroid in 2.5 mg increments to a minimum IV dose of dexamethasone 5 mg or equivalent
-Some patients may require additional or higher doses of one or more premedications to reduce the risk of IRRs.

Use: For the treatment of polyneuropathy of hereditary transthyretin-mediated amyloidosis.

Before using Onpattro tell your doctor about all your medical conditions or allergies.

Patisiran may harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

If you are pregnant, your name may be listed on a pregnancy registry to track the effects of patisiran on the baby.

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

Call your doctor for instructions if you miss an appointment for your Onpattro.

Since Onpattro is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

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

Some side effects may occur during the injection. Tell your medical caregiver if you feel warm, dizzy, nauseated, light-headed, itchy, sweaty, or have a headache, chest tightness, back pain, trouble breathing, or swelling in your face.

Common Onpattro side effects may include:

• cold symptoms such as stuffy nose, sneezing, sore throat.

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.