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Adverse event reports that FDA received

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Atezolizumab adverse event reports that FDA received

Name type
Generic name
Class
Programmed death Receptor-1 blocking antibody
Also reported as
Atezolizumab 1200mg

What a report is

A report is not proof that the drug was the cause of the event.

FDA says:

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.

Source: openFDA, Drug Adverse Event Overview, section "Responsible use of the data". The site read the page on . The data have the reports that FDA received through .

FDA also says:

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 has not been scientifically or otherwise verified as to a cause and effect relationship and cannot be used to estimate the incidence of these events.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

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.

Source: openFDA, Response of the drug event API (meta.disclaimer). The site read the page on .

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

Drug reports received through . Device reports have a separate cutoff, 30 Sep 2026. Why a report count is not a rate.

Reports on file

From December 2011 to June 2026, FDA received 19,768 adverse event reports that name Atezolizumab. In these reports the drug is a suspect or interacting product.

In the same period, 1,694 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 1,887 reports in the 12 months to June 2026 and 1,714 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

Of the 1,332,454 drug reports that FDA received in the 12 months to June 2026, 1,887 (0.1%) name Atezolizumab. Reports from physicians were 78.1% of the reports that name Atezolizumab and 21.9% of all drug reports.

The number of people who use the product is not in the data. A count is not a rate. A count of reports is not a count of events or of patients, because one event can have more than one report.

There are many instances of duplicative reports and some reports do not contain all the necessary information.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

Suspect product

FDA records each drug in a report as suspect, concomitant or interacting. This page counts the reports in which Atezolizumab is suspect or interacting. FDA says:

Any number of the drugs may be marked as suspect if thought to be responsible for one or more of the reactions, but that information is not validated.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

Data version

openFDA FAERS release of 29 Oct 2026. Reports received through 30 Jun 2026.

Since the last update

FDA says:

Many factors can influence whether or not an event will be reported, such as the time a product has been marketed and publicity about an event.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

The information in these reports cannot be used to estimate the incidence (occurrence rates) of the events reported.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

The latest update of the FDA data, recorded on , changed no count of this page.

  • In April to June 2026, FDA received 485 reports that name Atezolizumab.
  • In January to March 2026, FDA received 389.
  • In April to June 2025, FDA received 421.

April to June 2026 is the latest closed quarter in the data. A closed quarter is a quarter for which the FDA files have most of the reports.

All updatesFeed of updates (RSS)

Reaction lookup

These are the reaction terms that the reports record, with the number of reports for each term. Type a term or a plain word to find its count.

What this list leaves out

The table lists the 956 reaction terms that 5 or more reports record. A term with fewer than 5 reports is not in the table.

The site keeps reaction terms for 19,758 of the 19,768 reports (99.9%).

The reports of the other years are not in the counts.

So a count in the table can be lower than the count of FDA.

The table shows the first 50 of 956 terms.

Reaction terms in the reports that name Atezolizumab, most reports first
Reaction term (MedDRA) and plain meaningReportsShare of the 19,768 reports
Off label useused for a purpose or in a way not on the label1,3226.7%
Diarrhoealoose or frequent stools1,1936%
Deaththe patient died; cause not stated by this term1,1315.7%
Pyrexiafever1,0765.4%
Anaemialow red blood cells1,0655.4%
Disease progressionthe disease advanced9825%
Fatiguetiredness9784.9%
Nauseafeeling sick7824%
Pneumonialung infection7723.9%
Pneumonitis7563.8%
Hypothyroidismunderactive thyroid7553.8%
Decreased appetitereduced appetite7173.6%
Hypertensionhigh blood pressure6743.4%
Dyspnoeashortness of breath6613.3%
Febrile neutropeniafever with low white blood cells6503.3%
Thrombocytopenialow platelets6333.2%
Colitisinflamed bowel5913%
Vomitingbeing sick5893%
Neutropenialow neutrophils, a type of white blood cell5822.9%
Rashskin rash5732.9%
Astheniaweakness or lack of energy5472.8%
Acute kidney injurysudden loss of kidney function5362.7%
Constipation4772.4%
Intentional product use issuedeliberate use not as intended4612.3%
Platelet count decreasedlow platelet count4592.3%
Neutrophil count decreased4552.3%
Alanine aminotransferase increasedraised liver enzyme (ALT)4502.3%
Proteinuriaprotein in the urine4342.2%
Abdominal painstomach or belly pain4182.1%
Sepsisa severe body-wide response to infection4172.1%
Aspartate aminotransferase increasedraised liver enzyme (AST)4132.1%
Hyperthyroidismoveractive thyroid3781.9%
Drug ineffectivethe medicine did not work as expected3561.8%
Pruritusitching3471.8%
Hyponatraemialow blood sodium3451.7%
Adrenal insufficiencythe adrenal glands produce too little hormone3351.7%
White blood cell count decreasedlow white cell count3321.7%
General physical health deteriorationgeneral decline in health3301.7%
Hepatitis3271.7%
Hypokalaemialow blood potassium2951.5%
Ascitesfluid in the abdomen2851.4%
Neuropathy peripheralnerve damage in hands or feet2801.4%
Myocarditisinflammation of the heart muscle2781.4%
Interstitial lung diseasescarring or inflammation of lung tissue2771.4%
Urinary tract infectionbladder or urinary infection2721.4%
Arthralgiajoint pain2611.3%
Cough2481.3%
Infusion related reactiona reaction during or soon after an infusion2451.2%
Headachehead pain2401.2%
Alopeciahair loss2391.2%

Download all 956 terms of Atezolizumab (CSV)

The counts add to more than 19,768 reports, because one report can record more than one term. FDA says:

No individual drug is connected to any individual reaction. When a report lists multiple drugs and multiple reactions, there is no way to conclude from the data therein that a given drug is responsible for a given reaction.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

The CSV file has the same rows and the same limits. Its last row is a note that says so.

MedDRA term

The person who codes a report selects the preferred term that agrees best with the description of the reporter. The words under a term are the plain meaning that this site gives.

Not the label

The FDA-approved label of a product lists its adverse reactions. See the official pages at the end of this page.

Same ingredient, other names

Reporters write a brand name or a generic name. Each name has its own page and its own count.

Names of Atezolizumab with a page, in the order generic names, brand names, names as reported
NameName typeReports
Atezolizumab (this page)Generic name19,768
TecentriqBrand name16,957

Sum of the separately reported names: 36,725. A report that names two of these names is in the sum two times. The sum is not the number of reports for the ingredient.

FDA says:

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.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

Importantly, the AEMS data by themselves are not an indicator of the safety profile of the drug or biologic.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

Outcomes by year

The table gives the outcomes that the reporters gave, in the terms of FDA.

Outcomes in the reports that name Atezolizumab, by the year of the openFDA file that holds the report

The table continues to the right.

Year of the openFDA fileReportsSeriousDeathLife-threateningHospitalization (initial or prolonged)Disability or Permanent DamageCongenital Anomaly/Birth DefectOther Serious (Important Medical Events)Not serious
2015440130020
2016185178241115490197
2017624610113515021609914
20181,0441,0152087374727027329
20191,3831,3532779897027038830
20201,7931,757366971,16324064536
20212,4102,3604901171,4353201,03250
20223,2363,1705511801,9662541,44666
20234,0003,9217592532,3295301,82679
20242,0731,977394777161601,45696
20251,9571,92942894640901,35228
20261,0591,033194532856080826

An outcome in a report is not proof that the drug was the cause. The reporter gives the outcome, and FDA does not verify it. FDA says:

The information in these reports has not been scientifically or otherwise verified as to a cause and effect relationship and cannot be used to estimate the incidence of these events.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

The six headings with the names of FDA are the outcome terms of FDA. A report can have more than one outcome. The columns Serious and Not serious are the two values of the openFDA field serious. For the value serious, openFDA gives this description:

The adverse event resulted in death, a life threatening condition, hospitalization, disability, congenital anomaly, or other serious condition

Source: openFDA, Drug adverse event fields (YAML reference). The site read the page on .

The year is the year of the openFDA file that holds the latest version of the report. It is not always the year in which FDA first received the report. The chart of the next section uses the year of first receipt. The latest year is not complete.

Reports by year and month

Reports that name Atezolizumab, by the year in which FDA received them
02,5005,00020112015201820212024

The column of 2026 has an outline, because the year is not complete. It has the reports that FDA received through June 2026 only.

Show the figures of the chart as a table
Reports that name Atezolizumab, by the year in which FDA received them
YearReports
20111
20121
20143
201525
2016466
2017835
20181,380
20191,552
20201,926
20212,941
20223,171
20232,928
20241,857
20251,808
2026874
Reports that name Atezolizumab, by month, five years to June 2026
025050020222023202420252026

FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

Why a count moves

A count moves for many reasons. The guide gives FDA's words about them.

Patients and reporters

Age of the patient in the reports that name Atezolizumab
AgeReportsShareShare as a bar
Under 26under 0.1%
2 to 11130.1%
12 to 17110.1%
18 to 441,0725.4%
45 to 646,48432.8%
65 to 745,62428.5%
75 and over2,71713.7%
Age not given3,84119.4%
Sex of the patient in the reports that name Atezolizumab
SexReportsShareShare as a bar
Female7,02935.6%
Male9,40947.6%
Unknown or not given3,33016.8%
Type of reporter in the reports that name Atezolizumab
ReporterReportsShareShare as a bar
Physician15,44878.1%
Pharmacist4002%
Other health professional3,49517.7%
Lawyer1under 0.1%
Consumer or non-health professional3731.9%
Not given510.3%

Age and sex are as the report gives them. The reporter is the primary source in the report. 19.3% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Atezolizumab record
Indication as recorded (MedDRA)ReportsShare
Hepatocellular carcinoma3,46917.5%
Non-small cell lung cancer2,02210.2%
Small cell lung cancer extensive stage1,0435.3%
Small cell lung cancer7673.9%
Triple negative breast cancer7283.7%
Non-small cell lung cancer metastatic5412.7%

The reporter fills in the indication, and the field is often empty. Each share is of all 19,768 reports.

Drugs in the same reports

Other drugs that the reports of Atezolizumab name, in any role, in order of name
DrugReports that name the two
Acetaminophen1,672
Amlodipine966
Bevacizumab6,946
Carboplatin5,822
Cisplatin933
Dexamethasone1,482
Etoposide2,473
Omeprazole1,318
Ondansetron1,350
Paclitaxel3,257

The table has the 10 drug names that these reports name most. Two names in one report says only that the report recorded the two. It says nothing about the part of a product in the event.

FDA says:

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.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

Importantly, the AEMS data by themselves are not an indicator of the safety profile of the drug or biologic.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

Pages near this one

These links are for navigation. No count selected them. The class page lists each drug of the class.

Official pages

The site checked these addresses on . The links open in a new tab.

Cite this page

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Reported Reactions. Atezolizumab: adverse event reports that FDA received. https://reportedreactions.com/drug/atezolizumab/ Source: U.S. Food and Drug Administration, openFDA Drug Adverse Event (FAERS) files, release of . Reports received through .

Where the data come from

The counts come from the openFDA Drug Adverse Event (FAERS) bulk files, release of 29 Oct 2026. The files have the reports that FDA received through 30 Jun 2026. A drug name is the name on the report. The site matches it to a brand name or a generic name of the National Drug Code Directory of 2 Nov 2026. A class is the pharmacologic class (EPC) of the FDA label.

A report is in the count when it names Atezolizumab as a suspect or interacting product. The 1,694 reports that name it only as a concomitant medicine are not in the count. The site does not publish a report narrative, a lot number, a detail of a patient or the identity of a reporter. The record of FDA is the authority. See how the site counts reports, the data sources and the corrections page.

Questions

Do these reports show that Atezolizumab was responsible for the reactions?

No. FDA says:

For any given report, there is no certainty that a suspected drug caused the event.

Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of . The site read the page on .

A reaction can relate to the condition that the drug treats, to other medicines, or to something else.

Is this the list of reactions on the label of Atezolizumab?

No. It is a count of what people reported to FDA: 19,768 reports from December 2011 to June 2026. The FDA-approved label of a product lists its adverse reactions. The official pages at the end of this page link to the labels.

Who sent these reports?

Physician (78.1%), other health professional (17.7%) and pharmacist (2%). These are the types of reporter for the reports that name this drug.

If a manufacturer receives an adverse event report, it is normally required to send the report to FDA.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

How does a person report an adverse event?

FDA runs MedWatch, a program that takes voluntary reports from health professionals, patients and consumers. The guide on how to report has the links.