Pharmacologic class (EPC) · 2 drug pages

Selective T cell costimulation blocker: adverse event reports filed with FDA

4,131 reports list a drug in this class as a suspect or interacting product, 2005–2026.

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.

4,131
reports across the class: 0% of all reports; 337
reports, 12 months to June 2026: 323 in the 12 months before; 74.5%
marked serious by the reporter: 57.4% across all reports; 2
drugs with a page: brand and generic names counted separately

Selective T cell costimulation blocker 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 4,131 adverse event reports received by FDA, 0% of the database, from July 2005 to June 2026.

337 reports arrived in the 12 months to June 2026, close to the 323 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 74.5% of the class's reports are marked serious, 16.6% record death among the outcomes and 38.2% record hospitalisation, as reported.

Across the class the reactions recorded most often are off label use (9%), death (5.2%) and transplant rejection (4.7%). 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
Belatacept	generic	2,285	172	91.9%	Off label use
NulojixBelatacept	brand	1,846	165	53%	Product storage error

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 label9%372
Deaththe patient died; cause not stated by this term5.2%215
Transplant rejection4.7%196
Kidney transplant rejection4.6%190
Product storage errorthe product was stored wrongly4.2%174
Cytomegalovirus infection3.7%153
Drug ineffectivethe medicine did not work as expected3.7%151
Acute kidney injurysudden loss of kidney function3.5%143
Covid-19COVID-19 infection3.1%128
Hospitalisationadmission to hospital2.9%120
Pyrexiafever2.2%89
Product preparation error2.1%85
Sepsisa severe body-wide response to infection2%82
Intentional product use issuedeliberate use not as intended1.9%80
Pneumocystis jirovecii pneumonia1.9%80
Urinary tract infectionbladder or urinary infection1.8%76
Post transplant lymphoproliferative disorder1.8%74
Respiratory failurethe lungs could not supply enough oxygen1.6%67
Leukopenialow white blood cells1.5%64
Thrombotic microangiopathy1.5%62
Diarrhoealoose or frequent stools1.5%61
Pneumonialung infection1.5%61
Product preparation issuea problem preparing the product1.4%58
Adverse eventan unwanted medical event, type not specified1.4%57
Cytomegalovirus viraemia1.4%56

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

Death16.6%685

Life-threatening6.3%261

Hospitalisation (initial or prolonged)38.2%1,580

Disability0.7%29

Congenital anomaly0.3%11

Other serious53.4%2,207

Not serious25.5%1,052

Patient age

Under 20.1%5

2 to 110.1%5

12 to 171%41

18 to 4412.7%523

45 to 6426.6%1,097

65 to 7415.1%624

75 and over4.1%169

Age not given40.4%1,667

Who reported

Physician22.8%942

Pharmacist16.9%700

Other health professional43.9%1,815

Lawyer0.1%6

Consumer or non-health professional15.1%624

Not given1.1%44

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 Selective T cell costimulation blocker reports

Which drugs are in the Selective T cell costimulation blocker class on this site?

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

How many reports does the class have?

4,131 reports through June 2026, 337 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 (9%), death (5.2%), transplant rejection (4.7%), kidney transplant rejection (4.6%) and product storage error (4.2%).

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.