What the label lists and what reports show
Teplizumab side effects
Teplizumab's FDA label: “Most common adverse reactions were lymphopenia, vomiting, rash, leukopenia, diarrhea, neutropenia, increased liver transaminase and headache ( 6.1 ).” FAERS holds 566 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 rash (133 reports).
- No generic listed
- Boxed warning
Check it at the source: the teplizumab FDA label on DailyMed (effective August 14, 2026); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of TZIELD?TZIELD may cause serious side effects including: See " What is the most important information I should know about TZIELD? " Allergic (hypersensitivity) reactions: Serious allergic reactions can happen while receiving TZIELD. Your healthcare provider will watch you closely while you are receiving TZIELD and after your infusion for signs of a reaction. Tell your healthcare provider right away if you have any of the following symptoms of an allergic reaction: fever, joint pain, swollen lymph nodes (serum sickness) urticaria vomiting swelling of the face, lips, tongue, or throat (angioedema) rash trouble breathing The most common side effects of TZIELD include: decrease in white blood cell counts vomiting rash diarrhea increase in liver enzyme levels headache These are not all of the possible side effects of TZIELD. For more information, ask your healthcare provider or pharmacist. […]
Source: FDA drug label, Provention Bio, Inc., effective August 14, 2026 (SPL set e8a39a5f-139c-4510-9777-71cbb00138fa), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions were lymphopenia, vomiting, rash, leukopenia, diarrhea, neutropenia, increased liver transaminase and headache ( 6.1 ).
Table 3. Common Adverse Reactions Adverse reactions occurring in equal or more than 5% of participants in the TZIELD group, higher in TZIELD compared to placebo, in treatment course 1 through 28 days after the last…
| Adverse Reaction | TZIELD n=217 | Placebo n=111 |
|---|---|---|
| Lymphopenia Grouped term includes other related terms. | 51% | 3% |
| Rash | 51% | 9% |
| Leukopenia | 34% | 3% |
| Nausea | 34% | 12% |
| Headache | 29% | 16% |
| Vomiting | 26% | 5% |
| Neutropenia | 23% | 5% |
| Abdominal pain | 18% | 11% |
| Pyrexia | 16% | 3% |
| Alanine aminotransferase increased | 11% | 0% |
| Diarrhea | 10% | 6% |
| Cytokine release syndrome | 7% | 1% |
| Hypotension | 7% | 6% |
| Aspartate aminotransferase increased | 7% | 1% |
| Hemoglobin decreased | 5% | 4% |
| Chills | 5% | 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 serious adverse reactions are described elsewhere in the Prescribing Information: Viral Reactivation [see Warnings and Precautions (5.1) ] Cytokine Release Syndrome [see Warnings and Precautions (5.2) ] Serious Infections [see Warnings and Precautions (5.3) ] Lymphopenia [see Warnings and Precautions (5.4) ] Hypersensitivity Reactions [see Warnings and Precautions (5.5) ] Most common adverse reactions were lymphopenia, vomiting, rash, leukopenia, diarrhea, neutropenia, increased liver transaminase and headache ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Provention Bio, Inc. at 1-800-633-1610 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Placebo-Controlled Study in Adult and Pediatric Patients Aged 8 Years and Older with Stage 2 T1D (TN-10) The data in Table 2 are derived from the placebo-controlled study (Study TN-10) in adult and pediatric patients aged 8 years and older with Stage 2 T1D [see Clinical Studies (14.1) ]. These data reflect exposure of 44 patients of whom 93% completed the full 14-day treatment course. …
Source: FDA drug label, Provention Bio, Inc., effective August 14, 2026 (SPL set e8a39a5f-139c-4510-9777-71cbb00138fa), via openFDA; the full label on DailyMed
What do FAERS reports show?
566 reports list teplizumab among the medicines taken, each a report of something that happened, not proof the medicine caused it; 1 are coded as a death and 21 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 24 reactions below, 12 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?
- Teplizumab: 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