General Information

Onpattro (patisiran) contains a transthyretin-directed small interfering RNA. Onpattro utilizes a novel approach to target and reduce production of the TTR protein in the liver via the RNAi pathway. Reducing the TTR protein leads to a reduction in the amyloid deposits that accumulate in tissues.

Onpattro is specifically indicated for the treatment of the polyneuropathy of hereditary transthyretin-mediated amyloidosis in adults. 

Onpattro is supplied as a solution for intravenous infusion. Dosing is based on body weight. For patients weighing less than 100 kg, the recommended dosage is 0.3 mg/kg every 3 weeks by intravenous infusion. For patients weighing 100 kg or more, the recommended dosage is 30 mg once every 3 weeks. Infuse over approximately 80 minutes. Premedicate with a corticosteroid, acetaminophen, and antihistamines to reduce the risk of infusion related reactions.

If a dose is missed, administer Onpattro as soon as possible. If Onpattro is administered within 3 days of the missed dose, continue dosing according to the patient’s original schedule. If Onpattro is administered more than 3 days after the missed dose, continue dosing every 3 weeks thereafter. 

Clinical Results

FDA Approval

The FDA approval of Onpattro was based on the randomized, double-blind, placebo-controlled, global Phase III APOLLO study. The study enrolled 225 subjects who received intravenous Onpattro (0.3 mg per kg of body weight) or placebo once every 3 weeks for 18 months. The primary endpoint of the APOLLO study was the modified Neuropathy Impairment Score +7 (mNIS+7), which assesses motor strength, reflexes, sensation, nerve conduction and postural blood pressure. Patients treated with Onpattro had a mean 6.0-point decrease (improvement) in mNIS+7 score from baseline compared to a mean 28.0-point increase (worsening) for patients in the placebo group, resulting in a mean 34.0-point difference relative to placebo, after 18 months of treatment. Nearly all Onpattro-treated patients experienced a treatment benefit relative to placebo, and 56% of Onpattro-treated patients at 18 months of treatment experienced reversal of neuropathy impairment (as assessed by mNIS+7 score) relative to their own baseline, compared to four percent of patients who received placebo.

Side Effects

Adverse effects associated with the use of Onpattro may include, but are not limited to, the following:

upper respiratory tract infections

infusion-related reactions

Mechanism of Action

Onpattro (patisiran) is a double-stranded siRNA that causes degradation of mutant and wild-type TTR mRNA through RNA interference, which results in a reduction of serum TTR protein and TTR protein deposits in tissues. 

Additional Information

For additional information regarding polyneuropathy of hereditary transthyretin-mediated amyloidosis in adults or Onpattro, please visit https://www.onpattro.com/