What the label lists and what reports show
Obinutuzumab side effects
Obinutuzumab's FDA label: “The most common adverse reactions (incidence ≥ 20% and ≥ 2% greater in the GAZYVA treated arm in CLL and NHL, and incidence ≥ 5% in the GAZYVA treated arm in LN) were: Previously untreated CLL : infusion-related reactions and neutropenia.” FAERS holds 16,355 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is neutropenia (1,355 reports).
- No generic listed
- Boxed warning
Check it at the source: the obinutuzumab FDA label on DailyMed (effective December 19, 2025, Genentech, Inc.); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe most common adverse reactions (incidence ≥ 20% and ≥ 2% greater in the GAZYVA treated arm in CLL and NHL, and incidence ≥ 5% in the GAZYVA treated arm in LN) were: Previously untreated CLL : infusion-related reactions and neutropenia.
Table 11 Adverse Reactions (Incidence ≥ 10% and ≥ 2% Greater in the GAZYVA Arm) in Patients with Previously Untreated NHL (GALLIUM)
| Reaction | All Grades % | Grades 3 to 5 % | All Grades % | Grades 3 to 5 % |
|---|---|---|---|---|
| Infusion-Related Reaction Except where noted, individual events that meet the definition… | 72 | 12 | 60 | 8 |
| Neutropenia Includes adverse reactions reported as infusion-related reactions. | 53 | 49 | 47 | 41 |
| Thrombocytopenia | 14 | 7 | 8 | 3 |
| Upper Respiratory Tract Infection | 50 | 3 | 43 | 1 |
| Herpesvirus Infection | 18 | 3 | 14 | 1 |
| Pneumonia | 14 | 7 | 12 | 6 |
| Cough | 35 | < 1 | 28 | < 1 |
| Constipation | 32 | < 1 | 29 | < 1 |
| Diarrhea | 30 | 3 | 26 | 2 |
| Headache | 18 | < 1 | 15 | < 1 |
| Arthralgia | 16 | 0 | 14 | < 1 |
| Insomnia | 15 | < 1 | 12 | < 1 |
| Decreased Appetite | 14 | < 1 | 12 | < 1 |
| Pruritus | 11 | < 1 | 9 | 0 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following clinically significant adverse reactions are described elsewhere in the labeling: Hepatitis B virus reactivation [see Warnings and Precautions (5.1) ] Progressive multifocal leukoencephalopathy [see Warnings and Precautions (5.2) ] Infusion-related reactions [see Warnings and Precautions (5.3) ] Hypersensitivity reactions including serum sickness [see Warnings and Precautions (5.4) ] Tumor lysis syndrome [see Warnings and Precautions (5.5) ] Infections [see Warnings and Precautions (5.6) ] Neutropenia [see Warnings and Precautions (5.7) ] Thrombocytopenia [see Warnings and Precautions (5.8) ] Disseminated intravascular coagulation [see Warnings and Precautions (5.9) ] The most common adverse reactions (incidence ≥ 20% and ≥ 2% greater in the GAZYVA treated arm in CLL and NHL, and incidence ≥ 5% in the GAZYVA treated arm in LN) were: Previously untreated CLL : infusion-related reactions and neutropenia. ( 6 ) Relapsed or refractory non-Hodgkin lymphoma (NHL): infusion-related reactions, fatigue, neutropenia, cough, upper respiratory tract infections, and musculoskeletal pain. ( 6 ) Previously untreated NHL : infusion-related reactions, neutropenia, upper respiratory tract infections, cough, constipation, and diarrhea. …
Source: FDA drug label, Genentech, Inc., effective December 19, 2025 (SPL set df12ceb2-5b4b-4ab5-a317-2a36bf2a3cda), via openFDA; the full label on DailyMed
What do FAERS reports show?
16,355 reports list obinutuzumab among the medicines taken, each a report of something that happened, not proof the medicine caused it; 2,164 are coded as a death and 6,111 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 20 reactions below, 14 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Obinutuzumab: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions