Kesimptaofatumumab
According to the FDA label: KESIMPTA is indicated for the treatment of relapsing forms of multiple sclerosis (MS), to include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease, in adults. KESIMPTA is a CD20-directed cytolytic antibody indicated for the treatment of relapsing forms of multiple sclerosis (MS), to include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease, in adults. ( 1 )
32,441 adverse event reports submitted to the FDA (2008–2026)
Top Reported Adverse Events
The most frequently reported events in association with Kesimpta in the FAERS database. These are events reported by patients taking this medication, not necessarily caused by it. A single report may include multiple events.
Show these terms with plain-language definitions
Tap any term below for a plain-language definition.
Fatigue 5,478 reports
Extreme tiredness or lack of energy that does not improve with rest.
Full definition in the glossary → See all drugs reporting this event →Headache 4,593 reports
Pain in the head or upper neck.
Full definition in the glossary → See all drugs reporting this event →Pyrexia 3,534 reports
The medical term for fever, meaning a raised body temperature.
Full definition in the glossary → See all drugs reporting this event →Pain 3,524 reports
A general report of physical discomfort, used when no more specific location is given.
Full definition in the glossary →Chills 3,459 reports
A feeling of coldness, often with shivering, which can accompany a fever.
Full definition in the glossary →Influenza Like Illness 2,850 reports
A set of symptoms resembling the flu, such as fever, aches, and tiredness, without a confirmed flu diagnosis.
Full definition in the glossary →Nausea 1,791 reports
The feeling of sickness in your stomach that often comes before vomiting.
Full definition in the glossary → See all drugs reporting this event →Multiple Sclerosis Relapse 1,661 reports
A return or worsening of multiple sclerosis symptoms. It often appears in reports as part of the condition being treated.
Full definition in the glossary →COVID-19 1,515 reports
The illness caused by the SARS-CoV-2 coronavirus.
Full definition in the glossary →Asthenia 1,477 reports
Physical weakness or lack of strength.
Full definition in the glossary →Multiple Sclerosis 1,439 reports
A condition where the immune system affects the protective covering of nerves, which can disrupt movement and other functions. It often appears in reports as a condition being treated.
Full definition in the glossary →Gait Disturbance 1,414 reports
Difficulty walking normally, such as an unsteady or altered way of walking.
Full definition in the glossary →Hypoaesthesia 1,379 reports
Reduced sense of touch or numbness in part of the body. Also spelled hypoesthesia in American English.
Full definition in the glossary → See all drugs reporting this event →Feeling Abnormal 1,345 reports
A general report that the person did not feel like themselves, without a more specific description.
Full definition in the glossary →Malaise 1,340 reports
A general feeling of being unwell or uncomfortable, without a specific symptom.
Full definition in the glossary →
Ranked by frequency of reports, not severity. The most-reported event is not necessarily the most dangerous or the most common in patients taking this drug.
Who Is Reporting
Demographics of patients in FAERS reports that included this information. Not all reports include patient demographics.
By Sex
View reporter sex data as a table
| Sex | Reports |
|---|---|
| Female | 21,805 |
| Male | 7,505 |
| Unknown | 52 |
By Age Group
View age group data as a table
| Age group | Reports |
|---|---|
| 0-17 | 143 |
| 18-34 | 2,542 |
| 35-49 | 5,350 |
| 50-64 | 4,412 |
| 65-74 | 1,132 |
| 75+ | 601 |
This shows who filed reports, reflecting who takes this drug and who tends to report, not who is at greatest risk.
Reported Outcomes
Outcomes recorded in FAERS reports that included Kesimpta. A single report may involve multiple reactions, each with a different outcome. These categories are defined by FDA reporting guidelines, not by PillSignal.
View outcome data as a table
| Outcome | Reports |
|---|---|
| Non-Serious | 18,325 |
| Other Serious | 10,450 |
| Hospitalization | 4,451 |
| Death | 750 |
| Life-Threatening | 479 |
| Disability | 297 |
Serious outcomes are far more likely to be reported than mild ones, so this overstates how often outcomes are serious. A recorded death does not mean the drug caused it.
Report Volume Over Time
Number of FAERS reports received per quarter for Kesimpta. Changes in volume may reflect shifts in prescribing rates, media attention, or reporting behavior, not changes in the medication's safety profile.
View report trend as a table
| Year | Reports |
|---|---|
| 2008 | 2 |
| 2009 | 10 |
| 2010 | 102 |
| 2011 | 151 |
| 2012 | 236 |
| 2013 | 285 |
| 2014 | 275 |
| 2015 | 328 |
| 2016 | 232 |
| 2017 | 155 |
| 2018 | 162 |
| 2019 | 109 |
| 2020 | 680 |
| 2021 | 4,664 |
| 2022 | 7,298 |
| 2023 | 8,730 |
| 2024 | 4,694 |
| 2025 | 3,610 |
| 2026 (partial) | 718 |
The steep increase around 2004 reflects the FDA's move to electronic submission, not a change in this drug's safety. Trends track reporting volume, not risk.
Medications commonly reported with Kesimpta
In FDA adverse event reports that mention Kesimpta, these medications appeared most often in the same report.
- Ergocalciferol (2,195 reports)
- Gabapentin (1,144 reports)
- Acetaminophen (938 reports)
- Baclofen (916 reports)
- Rituximab (695 reports)
This reflects co-occurrence in submitted reports, not evidence of drug interaction or combined risk. People often report several medications taken for the same condition or for unrelated reasons. Talk to a doctor or pharmacist about your specific medications.
Related Drugs
Other medications with similar adverse event profiles in FDA FAERS reports.
Data Source
This data is sourced from the FDA's Adverse Event Monitoring System (AEMS), formerly FAERS, via the OpenFDA API. PillSignal is not affiliated with the FDA.
View this data on the FDA website →Data last updated: June 2026