Pharmacologic class (EPC) · 4 drug pages

Programmed death Ligand-1 blocker: adverse event reports filed with FDA

23,488 reports list a drug in this class as a suspect or interacting product, 2016–2026.

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.

23,488
reports across the class: 0.1% of all reports; 5,072
reports, 12 months to June 2026: 3,960 in the 12 months before; 94.8%
marked serious by the reporter: 57.4% across all reports; 4
drugs with a page: brand and generic names counted separately

Programmed death Ligand-1 blocker is a pharmacologic class (an FDA Established Pharmacologic Class) with 4 drug pages on this site. Together those drugs are listed as a suspect or interacting product in 23,488 adverse event reports received by FDA, 0.1% of the database, from February 2016 to June 2026.

5,072 reports arrived in the 12 months to June 2026, up 28% from 3,960 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 94.8% of the class's reports are marked serious, 30.4% record death among the outcomes and 31.6% record hospitalisation, as reported.

Across the class the reactions recorded most often are death (17.8%), malignant neoplasm progression (6.9%) and pneumonitis (4%). 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
ImfinziDurvalumab	brand	12,098	2,560	93.6%	Death
Durvalumab	generic	7,629	2,245	98.5%	Death
Avelumab	generic	2,024	113	97.1%	Off label use
BavencioAvelumab	brand	1,737	154	84.7%	Disease progression

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 term17.8%4,179
Malignant neoplasm progression6.9%1,626
Pneumonitis4%938
Radiation pneumonitis3.4%805
Diarrhoealoose or frequent stools3.4%794
Pyrexiafever3.2%747
Disease progressionthe disease advanced3.1%723
Off label useused for a purpose or in a way not on the label3%702
Interstitial lung diseasescarring or inflammation of lung tissue2.4%573
Dyspnoeashortness of breath2.4%570
Fatiguetiredness2.4%560
Pneumonialung infection2.3%535
Rashskin rash2.2%514
Anaemialow red blood cells2%465
Astheniaweakness or lack of energy2%464
Colitisinflamed bowel1.8%433
Nauseafeeling sick1.8%418
Neutrophil count decreased1.8%418
Hypothyroidismunderactive thyroid1.6%381
Thrombocytopenialow platelets1.6%379
Platelet count decreasedlow platelet count1.6%373
Decreased appetitereduced appetite1.5%362
Febrile neutropeniafever with low white blood cells1.5%353
Metastases to central nervous system1.5%351
Vomitingbeing sick1.4%325

Solid bar: share of all class reports. Hollow bar: the median share across the 4 member drugs, the reference used on each member's page. One report can record several terms.

Outcomes, patients and reporters

Outcomes recorded

Death30.4%7,144

Life-threatening6.9%1,618

Hospitalisation (initial or prolonged)31.6%7,427

Disability1.3%316

Congenital anomaly0%11

Other serious55.1%12,944

Not serious5.2%1,213

Patient age

Under 20%4

2 to 110%2

12 to 170%5

18 to 442%472

45 to 6420.8%4,880

65 to 7424.9%5,847

75 and over15.4%3,615

Age not given36.9%8,663

Who reported

Physician56.6%13,304

Pharmacist4.5%1,053

Other health professional14.4%3,386

Lawyer0%0

Consumer or non-health professional20.2%4,736

Not given4.3%1,009

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 Programmed death Ligand-1 blocker reports

Which drugs are in the Programmed death Ligand-1 blocker class on this site?

Imfinzi, Durvalumab, Avelumab and Bavencio. Class membership comes from the pharmacologic class (EPC) on the drug's FDA label.

How many reports does the class have?

23,488 reports through June 2026, 5,072 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 (17.8%), malignant neoplasm progression (6.9%), pneumonitis (4%), radiation pneumonitis (3.4%) and diarrhoea (3.4%).

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.