Pharmacologic class (EPC) · 2 drug pages

Small interfering RNA: adverse event reports filed with FDA

5,193 reports list a drug in this class as a suspect or interacting product, 2018–2026.

Read first · FDA's statement on these data

Adverse event reports submitted to FDA do not undergo extensive validation or verification. Therefore, a causal relationship cannot be established between product and reactions listed in a report. While a suspected relationship may exist, it is not medically validated and should not be the sole source of information for clinical decision making or other assumptions about the safety or efficacy of a product. Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product. openFDA, FDA

FDA adds: "There is no certainty that the reported event (adverse event or medication error) was actually due to the product. FDA does not require that a causal relationship between a product and event be proven, and reports do not always contain enough detail to properly evaluate an event." The information in these reports "cannot be used to estimate the incidence of these events."

Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated.

Not medical advice. This site counts what was reported to FDA. Questions about a medicine or device belong with a pharmacist or clinician.

5,193
reports across the class: 0% of all reports; 1,359
reports, 12 months to June 2026: 759 in the 12 months before; 75.2%
marked serious by the reporter: 57.4% across all reports; 2
drugs with a page: brand and generic names counted separately

Small interfering RNA is a pharmacologic class (an FDA Established Pharmacologic Class) with 2 drug pages on this site. Together those drugs are listed as a suspect or interacting product in 5,193 adverse event reports received by FDA, 0% of the database, from September 2018 to June 2026.

1,359 reports arrived in the 12 months to June 2026, up 79% from 759 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 75.2% of the class's reports are marked serious, 20% record death among the outcomes and 39.1% record hospitalisation, as reported.

Across the class the reactions recorded most often are death (14.7%), hospitalisation (8.4%) and intentional dose omission (6%). The class median share shown beside each term is the middle value across the member drugs; it is the comparison used on every drug page in this class.

The members table is ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Drugs in the class

Drug	Name type	Reports	Latest 12 months	Marked serious	Top term recorded
OnpattroPatisiran	brand	2,724	110	66.8%	Death
AmvuttraVutrisiran	brand	2,469	1,249	84.4%	Death

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Reports by month, five years

FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

Reactions recorded across the class

share of class reports recording the termmedian drug in the class

Deaththe patient died; cause not stated by this term14.7%761
Hospitalisationadmission to hospital8.4%438
Intentional dose omission6%312
Product dose omission issuea dose was missed5.9%304
Fatiguetiredness4.9%253
Falla fall4.4%226
Astheniaweakness or lack of energy3.4%175
Cardiac failureheart failure3.3%173
Dyspnoeashortness of breath3.2%164
Therapy interrupted3.1%160
Malaisegeneral feeling of being unwell2.6%137
Gait disturbancedifficulty walking2.5%131
Infusion related reactiona reaction during or soon after an infusion2.5%129
Pain in extremitypain in an arm or leg2.5%129
Painpain, site not specified2.3%122
Dizzinesslight-headedness or unsteadiness2.3%121
Diarrhoealoose or frequent stools2.3%118
Pneumonialung infection2.2%115
Hypoaesthesianumbness2.1%109
Nauseafeeling sick2.1%108
Weight decreasedweight loss2%105
Atrial fibrillationan irregular heart rhythm2%104
Unevaluable eventthe event could not be assessed1.9%101
Condition aggravatedthe condition being treated got worse1.9%100
Cerebrovascular accidentstroke1.9%98

Solid bar: share of all class reports. Hollow bar: the median share across the 2 member drugs, the reference used on each member's page. One report can record several terms.

Outcomes, patients and reporters

Outcomes recorded

Death20%1,037

Life-threatening0.9%49

Hospitalisation (initial or prolonged)39.1%2,032

Disability0.9%47

Congenital anomaly0%0

Other serious29.4%1,526

Not serious24.8%1,289

Patient age

Under 20%0

2 to 110%0

12 to 170%0

18 to 440.7%36

45 to 642.9%149

65 to 744.6%239

75 and over8.6%449

Age not given83.2%4,320

Who reported

Physician27%1,401

Pharmacist1.7%90

Other health professional20.6%1,071

Lawyer0%0

Consumer or non-health professional50.3%2,611

Not given0.4%20

Grey bar: all 20,646,523 reports in the database. Outcome flags are as the reporter set them and are not verified by FDA.

Questions about Small interfering RNA reports

Which drugs are in the Small interfering RNA class on this site?

Onpattro and Amvuttra. Class membership comes from the pharmacologic class (EPC) on the drug's FDA label.

How many reports does the class have?

5,193 reports through June 2026, 1,359 of them in the latest 12 months. A report listing two drugs of the class counts once for each.

What reactions are recorded most often?

death (14.7%), hospitalisation (8.4%), intentional dose omission (6%), product dose omission issue (5.9%) and fatigue (4.9%).

Can the members table be used to rank the drugs?

No. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." Drugs differ in how many people take them, in the conditions they treat, in time on the market and in how diligently reports are collected.

How do I report an adverse event?

Through FDA MedWatch (Form FDA 3500, or 1-800-FDA-1088) or to the manufacturer. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A class is the Established Pharmacologic Class most often attached to a drug's reports by openFDA's label harmonisation, or from the NDC Directory where reports carry none. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.