Pharmacologic class (EPC) · 2 drug pages

Hepatitis C virus nucleotide analog NS5B polymerase inhibitor: adverse event reports filed with FDA

18,232 reports list a drug in this class as a suspect or interacting product, 2009–2026.

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.

18,232
reports across the class: 0.1% of all reports; 27
reports, 12 months to June 2026: 103 in the 12 months before; 73.7%
marked serious by the reporter: 57.4% across all reports; 2
drugs with a page: brand and generic names counted separately

Hepatitis C virus nucleotide analog NS5B polymerase inhibitor 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 18,232 adverse event reports received by FDA, 0.1% of the database, from April 2009 to June 2026.

27 reports arrived in the 12 months to June 2026, down 74% from 103 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 73.7% of the class's reports are marked serious, 9.4% record death among the outcomes and 22.8% record hospitalisation, as reported.

Across the class the reactions recorded most often are fatigue (11.6%), drug ineffective (10.3%) and hepatitis C (9.2%). 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
SovaldiSofosbuvir	brand	10,810	6	61.3%	Fatigue
Sofosbuvir	generic	7,422	21	91.7%	Hepatitis C

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

Fatiguetiredness11.6%2,121
Drug ineffectivethe medicine did not work as expected10.3%1,872
Hepatitis Chepatitis C infection9.2%1,685
Headachehead pain8.3%1,510
Off label useused for a purpose or in a way not on the label7%1,285
Nauseafeeling sick7%1,278
Anaemialow red blood cells6.1%1,116
Insomniadifficulty sleeping5.5%997
Hepatocellular carcinoma4.8%876
Treatment failurethe treatment did not work4.4%808
Dyspnoeashortness of breath4.1%746
Astheniaweakness or lack of energy4%722
Diarrhoealoose or frequent stools3.8%684
Pruritusitching3.7%676
Dizzinesslight-headedness or unsteadiness3.7%674
Vomitingbeing sick3.4%627
Ascitesfluid in the abdomen3.4%614
Decreased appetitereduced appetite3.1%558
Hepatic failureliver failure2.9%532
Pyrexiafever2.9%531
Arthralgiajoint pain2.9%528
Rashskin rash2.9%523
Malaisegeneral feeling of being unwell2.8%509
Depressionlow mood2.6%479
Myalgiamuscle pain2.6%467

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

Death9.4%1,714

Life-threatening3%550

Hospitalisation (initial or prolonged)22.8%4,162

Disability1.3%233

Congenital anomaly0.1%14

Other serious61.9%11,291

Not serious26.3%4,797

Patient age

Under 20.1%11

2 to 110.1%11

12 to 170.1%14

18 to 446.1%1,105

45 to 6442.3%7,718

65 to 7410.8%1,967

75 and over4.3%791

Age not given36.3%6,615

Who reported

Physician32.9%6,002

Pharmacist9.7%1,760

Other health professional28.8%5,249

Lawyer0%6

Consumer or non-health professional26.5%4,823

Not given2.2%392

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 Hepatitis C virus nucleotide analog NS5B polymerase inhibitor reports

Which drugs are in the Hepatitis C virus nucleotide analog NS5B polymerase inhibitor class on this site?

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

How many reports does the class have?

18,232 reports through June 2026, 27 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?

fatigue (11.6%), drug ineffective (10.3%), hepatitis C (9.2%), headache (8.3%) and off label use (7%).

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.