Brand name · Zolbetuximab
Vyloy: adverse event reports filed with FDA
1,109 reports list it as a suspect or interacting product, 2024–2026.
- 1,109
- reports as suspect product
- 0% of all reports · about 703 a year
- 618
- reports, 12 months to June 2026
- 491 in the 12 months before
- 84.1%
- marked serious by the reporter
- 57.4% across all reports
- 12.3%
- record death among outcomes, as reported
- 136 reports · not verified by FDA
1,109 adverse event reports received by FDA list the brand name Vyloy (zolbetuximab) as a suspect or interacting product, from December 2024 to June 2026. A further 1 reports list it only as a concomitant medication, and those are not counted in the figures on this page.
In the 12 months to June 2026, 618 reports listed it, up 26% from 491 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 703 reports a year and 0% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.
The reactions recorded most often are nausea (38.8%), vomiting (17.3%) and decreased appetite (13.8%). A report can list several reactions, so shares add to more than 100%; 260 different terms appear across these reports. Nausea is recorded in 38.8% of these reports, against 3.8% of all reports in the database.
84.1% of the reports are marked serious by the reporter; 12.3% record death among the outcomes and 32.4% record hospitalisation, as reported. 50.2% of the reports came from physicians, and the largest patient age group is 75 and over (32.4%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."
Reports by month, five years
Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.
By year received
2026 covers reports received through June 2026 only.
Reactions recorded in the reports
share of Vyloy reports recording the termall reports in the database
- Nauseafeeling sick38.8%430
- Vomitingbeing sick17.3%192
- Decreased appetitereduced appetite13.8%153
- Hypoalbuminaemia9.5%105
- Ascitesfluid in the abdomen8.9%99
- Blood albumin decreased6.5%72
- Diarrhoealoose or frequent stools5%55
- Myelosuppression4.6%51
- Oedema peripheralswelling of the legs, ankles or hands4.6%51
- Malaisegeneral feeling of being unwell4.2%47
- Oedemaswelling from fluid3.8%42
- Off label useused for a purpose or in a way not on the label3.5%39
- Pyrexiafever3.2%36
- Gastritisinflamed stomach lining3.2%35
- Deaththe patient died; cause not stated by this term3.1%34
- Dehydrationdehydration2.9%32
- Hypoaesthesianumbness2.9%32
- Weight decreasedweight loss2.9%32
- Product use issuea problem in how the product was used2.8%31
- Platelet count decreasedlow platelet count2.7%30
- Abdominal painstomach or belly pain2.5%28
- Neuropathy peripheralnerve damage in hands or feet2.4%27
- Renal impairmentreduced kidney function2.3%26
- Abdominal pain upperupper stomach pain2.3%25
- Fatiguetiredness2%22
- Inappropriate schedule of product administrationthe product was taken at the wrong times2%22
- Infusion related reactiona reaction during or soon after an infusion1.9%21
- Interstitial lung diseasescarring or inflammation of lung tissue1.9%21
Top 30 of 260 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the share of all reports in the database; it describes the reports, not the patients. 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."
Outcomes recorded
Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 20,646,523 reports. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."
Patients and reporters
Patient age
Patient sex
Who reported
Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 20.8% of reports give the United States as the country of the event or reporter.
Reason for use recorded
| Indication as recorded (MedDRA) | Reports | Share |
|---|---|---|
| Gastric cancer | 557 | 50.2% |
| Gastric cancer stage iv | 45 | 4.1% |
| Gastric cancer recurrent | 42 | 3.8% |
| Adenocarcinoma gastric | 34 | 3.1% |
| Oesophageal carcinoma | 28 | 2.5% |
| Metastatic gastric cancer | 18 | 1.6% |
The indication field is filled in by the reporter and is often blank; shares are of all 1,109 reports.
In context
| Measure | Vyloy | All reports |
|---|---|---|
| Reports as suspect product | 1,109 | 20,646,523 |
| Share of that pool | — | 0% |
| Reports, latest 12 months | 618 | 1,332,454 |
| Marked serious | 84.1% | 57.4% |
| Death recorded among outcomes, per 1,000 reports | 123 | 91 |
| Hospitalisation recorded, per 1,000 reports | 324 | 213 |
| Consumer-filed share | 1.5% | 45.8% |
| Top term, share of reports | Nausea 38.8% | 3.8% |
Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. 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."
Questions about Vyloy reports
How many adverse event reports has FDA received for Vyloy?
1,109 reports list Vyloy as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 618 of them arrived in the latest 12 months. Another 1 list it only as a concomitant medication.
What reactions are recorded in Vyloy reports?
nausea (38.8%), vomiting (17.3%), decreased appetite (13.8%), hypoalbuminaemia (9.5%) and ascites (8.9%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Vyloy was responsible.
How serious are the reports?
84.1% are marked serious by the reporter. Among the outcomes recorded, 12.3% of reports include death and 32.4% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.
Who files these reports?
physician (50.2%), other health professional (25.4%) and pharmacist (22.8%). Most reports reach FDA through the manufacturer, which must forward reports it receives.
Are reports for Vyloy rising?
618 reports in the 12 months to June 2026, up 26% from 491 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.
Do these reports show that Vyloy was responsible for these reactions?
No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.
Is this a list of the side effects of Vyloy?
No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.
How do I report an adverse event?
Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. 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 report counts here when it lists Vyloy as a suspect or interacting product; reports listing it only as a concomitant medication (1) are excluded. 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.