benralizumab Side Effects
Also known as: Fasenra
Analysis of 17,680 adverse event reports submitted to the FDA from 2012 to 2025.
Total Reports
17,680
Death-Related
1,749
9.9% of reports
Hospitalizations
4,130
23.4% of reports
Top Indication
Asthma
Most Reported Adverse Reactions
Who Reports Side Effects
Gender Distribution
Age Distribution
Reporting Trend by Year
Reactions in Death Reports
Top reactions reported in 1,749 reports where death was an outcome. These are voluntarily reported and do not establish causation.
| Reaction | Reports |
|---|---|
| DEATH | 1,434 |
| PNEUMONIA | 45 |
| ASTHMA | 42 |
| COVID-19 | 26 |
| RESPIRATORY FAILURE | 22 |
| DRUG INEFFECTIVE | 21 |
| DYSPNOEA | 20 |
| CARDIAC ARREST | 19 |
| MYOCARDIAL INFARCTION | 16 |
| FALL | 13 |
| PRODUCT DOSE OMISSION ISSUE | 13 |
| ABORTION SPONTANEOUS | 12 |
| CHRONIC OBSTRUCTIVE PULMONARY DISEASE | 12 |
| EPILEPSY | 12 |
| GENERAL PHYSICAL HEALTH DETERIORATION | 12 |
| INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION | 11 |
| LUNG DISORDER | 11 |
| CARDIAC FAILURE | 10 |
| MALAISE | 9 |
| OFF LABEL USE | 9 |
Reactions in Hospitalization Reports
Top reactions in 4,130 reports where hospitalization was an outcome.
| Reaction | Reports |
|---|---|
| ASTHMA | 1,048 |
| DYSPNOEA | 536 |
| PNEUMONIA | 464 |
| DRUG INEFFECTIVE | 459 |
| COUGH | 217 |
| PRODUCT DOSE OMISSION ISSUE | 197 |
| WHEEZING | 180 |
| COVID-19 | 175 |
| PYREXIA | 172 |
| INAPPROPRIATE SCHEDULE OF PRODUCT ADMINISTRATION | 171 |
| MALAISE | 170 |
| FALL | 157 |
| HEADACHE | 145 |
| FATIGUE | 126 |
| ILLNESS | 123 |
| INFLUENZA | 116 |
| ASTHENIA | 103 |
| PAIN | 103 |
| CHRONIC OBSTRUCTIVE PULMONARY DISEASE | 102 |
| INFECTION | 98 |
Nearby — Related Medications
What the FAERS Data Reveals About benralizumab Side Effects
The FDA Adverse Event Reporting System (FAERS) contains 17,680 voluntary reports linked to benralizumab and its brand equivalents (Fasenra), spanning 2012 through 2025. Of those, 1,749 (9.9%) listed death as an outcome and 4,130 (23.4%) involved hospitalization. The most common indication reported alongside adverse events was Asthma.
Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 70% were female and 30% male; age distribution skews toward 45-64, with 1,909 reports in that bracket. The single most reported reaction is asthma with 2,775 submissions, followed by dyspnoea and death.
FAERS is a signal-detection tool, not a scorecard. Reports are voluntary, and a single case may list multiple suspect drugs, so numbers above should not be read as incidence rates or per-patient risk. Widely prescribed drugs naturally accumulate more reports than niche therapies even when individual risk is low. These aggregates are useful for spotting patterns that merit further pharmacovigilance, not for choosing between medications. This page is for educational reference only and is not medical advice — speak with a licensed clinician about any side-effect concerns.
Read our methodology — how this data is sourced, computed, and verified.