BRANMOOR
THURSDAY · 14 MAY 2026

Keytruda

FDA Adverse Event Reporting System · 2025 window

Rank #38 by volume 10,519 reports in 2025

2025 report counts

Total adverse-event reports
10,519
Classified as serious
9,490
Reports with fatal outcome
1,723
Fatality share of serious reports
18.2%
Rank in window (by total report volume)
#38 of 500

Top reported reactions (serious-only)

The 10 most-reported reactions among serious-classified FAERS reports for this drug in 2025. MedDRA preferred terms.

Reaction (MedDRA PT)2025 reports
Malignant Neoplasm Progression 1,242
Death 579
Diarrhoea 550
Neuropathy Peripheral 423
Pyrexia 406
Therapy Partial Responder 400
Rash 396
Decreased Appetite 395
Fatigue 356
Hypertension 356

Important caveats

FAERS report counts are a reporting signal, not a clinical assertion of causation. Higher report volumes correlate with: larger treated populations, established manufacturer pharmacovigilance infrastructure, sicker patient populations (specialty biologics for serious disease will always attract more reports than common over-the-counter agents), and reporter familiarity with the reporting workflow.

The paid FAERS Signal Surveillance product adds the disproportionality analysis (Information Component, Empirical Bayes Geometric Mean, Proportional Reporting Ratio) that normalizes these confounders and surfaces emerging signal against the FAERS baseline. See the product page.

For the canonical FDA record, see the FAERS Public Dashboard.

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