Key takeaways
- Onpattro (patisiran) is given as an intravenous (IV) infusion by a healthcare professional every 3 weeks. An IV infusion is an injection given into a vein over a period of time.
- Onpattro infusions last around 80 minutes, but the total appointment time is usually at least 3 hours.
- Before each infusion, you’ll receive some premedications that usually include a corticosteroid, antihistamines, and acetaminophen. These can help with side effects.
Onpattro is approved by the Food and Drug Administration (FDA) to treat polyneuropathy (damage to multiple nerves in the body) caused by a condition called hereditary amyloid transthyretin-mediated (ATTR) amyloidosis.
Onpattro belongs to a drug class called RNA interference therapy (sometimes called gene silencers). Onpattro is not available in a generic version.
Keep reading for specific information about the dosage of Onpattro, including its strength and how you’ll receive the medication.
Read on for recommended dosages of Onpattro and other details about the drug.
Onpattro form
Onpattro comes as a solution that’s given as an intravenous (IV) infusion. It’s always given by a healthcare professional.
Onpattro strength
Onpattro comes in one strength of 2 milligrams per milliliter of solution (mg/mL).
Typical dosages
Typically, your doctor will prescribe your Onpattro dosage based on your weight.
The following information describes dosages that are commonly used in adults. Your doctor will determine the best dosage to fit your needs.
Dosage for polyneuropathy caused by hereditary ATTR amyloidosis
Your Onpattro dose will depend on your body weight in kilograms (kg). For reference, 1 kg equals about 2.2 pounds (lb).
If you weigh less than 100 kg, (about 220 lb): Your dosage will be 0.3 milligrams (mg)/kg. Typically, you’ll receive this dosage every 3 weeks.
If you weigh more than 100 kg: Your dosage will likely be 30 mg given every 3 weeks.
On the day of your infusion, you will receive some required medications before your Onpattro infusion begins. These are referred to as premedications and usually include a corticosteroid, two different antihistamines, and acetaminophen. These are given at least 60 minutes before your Onpattro injection to help with side effects during your infusion.
The table shows the typical dosage schedule. Your doctor will choose a dose that suits your needs.
| Body weight | Onpattro dose | Frequency of dose |
|---|---|---|
| less than 100 kg | 0.3 mg/kg | every 3 weeks |
| 100 kg or more | 30 mg | every 3 weeks |
For more information about your specific dosage, talk with your doctor.
Long-term treatment
Onpattro is meant to be used as a long-term treatment. If you and your doctor determine that Onpattro is safe and effective for you, you’ll likely receive it long term.
Before you start Onpattro, your doctor will discuss your treatment plan with you.
The Onpattro dosage your doctor prescribes will depend on several factors. These include:
- your body weight
- how your body responds to Onpattro
- side effects you may have with Onpattro
Other medical conditions you have can also affect your Onpattro dosage.
Your doctor or another healthcare professional will give you an intravenous (IV) infusion of Onpattro. You’ll likely go to your doctor’s office, an infusion center, or a hospital to receive your infusion. The Onpattro infusion takes about 80 minutes. However, you will be given your premedications at least 60 minutes before your Onpattro infusion starts, so you’ll likely be at the infusion center for at least 3 hours.
If you have questions about receiving Onpattro, talk with your doctor or pharmacist.
If you miss your appointment for an Onpattro infusion, call your doctor’s office as soon as possible to reschedule. They’ll adjust your dosing schedule as needed.
If you need help remembering your appointments, try setting an alarm or downloading a reminder app on your phone.
Here are some frequently asked questions about Onpattro.
Is the dosage of Onpattro similar to the dosage of Amvuttra or Tegsedi?
No, the way Onpattro is given is different than Amvuttra (vutrisiran) and Tegsedi (inotersen). All three drugs are liquids, but they are given differently:
- Onpattro is given as an intravenous (IV) infusion every 3 weeks
- Amvuttra is given as a subcutaneous (under the skin) injection administered by a healthcare professional every 3 months
- Tegsedi can be self-administered at home as a subcutaneous injection every week
The dose in milligrams for each drug also differs because they have different active ingredients. Your doctor will prescribe the drug and the dosage that’s right for you.
To learn more about how these drugs compare, talk with your doctor.
How long does it take for Onpattro to start working?
Onpattro starts to work after your first dose. Because of how the drug works, you likely won’t feel the drug working in your body. But your doctor will monitor you during treatment to check whether the drug is working to treat your condition.
Over time, you may notice your symptoms easing. Even if you don’t notice any improvement in your condition, Onpattro can still help slow down the progression (worsening) of damage to your nerves from your hereditary ATTR amyloidosis.
Talk with your doctor if you have questions about what to expect with Onpattro treatment.
Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.