Pharmacologic class (EPC) · 2 drug pages

Endoglycosidase: adverse event reports filed with FDA

5,659 reports list a drug in this class as a suspect or interacting product, 2004–2026.

Read first · FDA's statement on these data

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. openFDA, FDA

FDA adds: "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 "cannot be used to estimate the incidence of these events."

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.

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

5,659
reports across the class: 0% of all reports; 906
reports, 12 months to June 2026: 1,900 in the 12 months before; 47.1%
marked serious by the reporter: 57.4% across all reports; 2
drugs with a page: brand and generic names counted separately

Endoglycosidase is a pharmacologic class (an FDA Established Pharmacologic Class) with 2 drug pages on this site. Together those drugs are listed as a suspect or interacting product in 5,659 adverse event reports received by FDA, 0% of the database, from May 2004 to June 2026.

906 reports arrived in the 12 months to June 2026, down 52% from 1,900 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 47.1% of the class's reports are marked serious, 15.4% record death among the outcomes and 25.4% record hospitalisation, as reported.

Across the class the reactions recorded most often are off label use (21.1%), no adverse event (16.2%) and diarrhoea (13.6%). The class median share shown beside each term is the middle value across the member drugs; it is the comparison used on every drug page in this class.

The members table is ordered by report count for navigation only. 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."

Drugs in the class

Drug	Name type	Reports	Latest 12 months	Marked serious	Top term recorded
PhesgoPertuzumab, trastuzumab, and hyaluronidase-zzxf	brand	4,489	694	34%	No adverse event
Hyaluronidase	generic	1,170	212	97.3%	Fatigue

Ordered by report count for navigation only. 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."

Reports by month, five years

FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

Reactions recorded across the class

share of class reports recording the termmedian drug in the class

Off label useused for a purpose or in a way not on the label21.1%1,195
No adverse eventno adverse event was reported16.2%915
Diarrhoealoose or frequent stools13.6%767
Fatiguetiredness9.9%560
Painpain, site not specified9.4%530
Astheniaweakness or lack of energy8.1%457
Alopeciahair loss8%455
Pyrexiafever7.9%449
Arthralgiajoint pain7.8%439
Abdominal discomfortstomach discomfort7.4%421
Dyspnoeashortness of breath7.4%421
Headachehead pain7.4%416
Vomitingbeing sick7.3%411
Malaisegeneral feeling of being unwell7.1%404
Rashskin rash7.1%403
Decreased appetitereduced appetite7.1%399
Hypertensionhigh blood pressure6.9%391
Blood cholesterol increasedraised cholesterol6.7%381
Dizzinesslight-headedness or unsteadiness6.6%376
Nauseafeeling sick6.6%374
Condition aggravatedthe condition being treated got worse6.5%370
Arthropathy6.4%364
Maternal exposure during pregnancythe mother took the medicine during pregnancy6.4%364
Pruritusitching6.4%363
Hypoaesthesianumbness6.4%362

Solid bar: share of all class reports. Hollow bar: the median share across the 2 member drugs, the reference used on each member's page. One report can record several terms.

Outcomes, patients and reporters

Outcomes recorded

Death15.4%871

Life-threatening13.4%761

Hospitalisation (initial or prolonged)25.4%1,440

Disability13.7%773

Congenital anomaly5.1%289

Other serious33.5%1,894

Not serious52.9%2,995

Patient age

Under 20.1%5

2 to 110%0

12 to 170%0

18 to 4416.2%915

45 to 6431.9%1,806

65 to 7412.5%705

75 and over6.9%390

Age not given32.5%1,838

Who reported

Physician42.8%2,422

Pharmacist7.6%428

Other health professional21.5%1,219

Lawyer0%0

Consumer or non-health professional27.4%1,552

Not given0.7%38

Grey bar: all 20,646,523 reports in the database. Outcome flags are as the reporter set them and are not verified by FDA.

Questions about Endoglycosidase reports

Which drugs are in the Endoglycosidase class on this site?

Phesgo and Hyaluronidase. Class membership comes from the pharmacologic class (EPC) on the drug's FDA label.

How many reports does the class have?

5,659 reports through June 2026, 906 of them in the latest 12 months. A report listing two drugs of the class counts once for each.

What reactions are recorded most often?

off label use (21.1%), no adverse event (16.2%), diarrhoea (13.6%), fatigue (9.9%) and pain (9.4%).

Can the members table be used to rank the drugs?

No. 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." Drugs differ in how many people take them, in the conditions they treat, in time on the market and in how diligently reports are collected.

How do I report an adverse event?

Through FDA MedWatch (Form FDA 3500, or 1-800-FDA-1088) or to the manufacturer. 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 class is the Established Pharmacologic Class most often attached to a drug's reports by openFDA's label harmonisation, or from the NDC Directory where reports carry none. 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.